chore: bump version to 4.4.6-ba7opf.9.18

splitRingAtAntimeridian used to drop any edge crossing ±180°, leaving
visible gaps in WAZ zone outlines (zone 31's 40°N Pacific boundary,
zone 1/19's polar arcs, zone 32's Antarctic arc). The edge is now split
in two at ±180° with interpolated latitude, each half kept in its own
segment, so outlines close across the map's left/right edges.
normalizeLon now maps to (-180, 180] so edges ENDING on the
antimeridian are not mistaken for crossings.

.github/copilot-instructions.md

@@ -0,0 +1,5 @@
+# GitHub Copilot Instructions
+
+Read `AGENTS.md` first, then `CLAUDE.md`.
+
+`AGENTS.md` contains the architecture, module boundaries, implementation details, conventions, and gotchas.

.github/dependabot.yml

@@ -0,0 +1,6 @@
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/release.yml

@@ -16,59 +16,64 @@ jobs:
       contents: write
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
 
       - name: Setup Java
         uses: actions/setup-java@v5
         with:
           distribution: 'temurin'
-          java-version: '17'
+          java-version: '21'
 
       - name: Setup Gradle
-        uses: gradle/actions/setup-gradle@v5
+        uses: gradle/actions/setup-gradle@v6
 
       - name: Assemble Artifacts
-        run: |
-          ./gradlew assembleRelease
-          ./gradlew bundleRelease
+        run: ./gradlew assembleRelease bundleRelease
 
       - name: Sign APK
-        uses: r0adkll/sign-android-release@v1
-        id: sign_apk
-        with:
-          releaseDirectory: app/build/outputs/apk/release
-          signingKeyBase64: ${{ secrets.KEY_STORE }}
-          keyStorePassword: ${{ secrets.KEY_STORE_PASSWORD }}
-          alias: ${{ secrets.KEY_ALIAS }}
-          keyPassword: ${{ secrets.KEY_PASSWORD }}
-        env:
-          BUILD_TOOLS_VERSION: "36.0.0"
+        run: |
+          echo "${{ secrets.KEY_STORE }}" | base64 -d > keystore.jks
+          APK=$(find app/build/outputs/apk/release -name "*.apk" | head -1)
+          BUILD_TOOLS=$(ls -d ${ANDROID_HOME}/build-tools/*/ | sort -V | tail -1)
+          ${BUILD_TOOLS}apksigner sign \
+            --ks keystore.jks \
+            --ks-pass pass:${{ secrets.KEY_STORE_PASSWORD }} \
+            --ks-key-alias ${{ secrets.KEY_ALIAS }} \
+            --key-pass pass:${{ secrets.KEY_PASSWORD }} \
+            --out app/build/outputs/apk/release/look4sat.apk \
+            "$APK"
+          rm keystore.jks
 
       - name: Sign Bundle
-        uses: r0adkll/sign-android-release@v1
-        id: sign_bundle
-        with:
-          releaseDirectory: app/build/outputs/bundle/release
-          signingKeyBase64: ${{ secrets.KEY_STORE }}
-          keyStorePassword: ${{ secrets.KEY_STORE_PASSWORD }}
-          alias: ${{ secrets.KEY_ALIAS }}
-          keyPassword: ${{ secrets.KEY_PASSWORD }}
-        env:
-          BUILD_TOOLS_VERSION: "36.0.0"
-
-      - name: Rename Artifacts
         run: |
-          mv ${{steps.sign_apk.outputs.signedReleaseFile}} app/build/outputs/apk/release/look4sat.apk
-          mv ${{steps.sign_bundle.outputs.signedReleaseFile}} app/build/outputs/apk/release/look4sat.aab
+          echo "${{ secrets.KEY_STORE }}" | base64 -d > keystore.jks
+          AAB=$(find app/build/outputs/bundle/release -name "*.aab" | head -1)
+          jarsigner -verbose -sigalg SHA256withRSA -digestalg SHA-256 \
+            -keystore keystore.jks \
+            -storepass ${{ secrets.KEY_STORE_PASSWORD }} \
+            -keypass ${{ secrets.KEY_PASSWORD }} \
+            "$AAB" ${{ secrets.KEY_ALIAS }}
+          rm keystore.jks
 
-      - name: Deploy Bundle
-        uses: r0adkll/upload-google-play@v1
+      - name: Setup Ruby
+        uses: ruby/setup-ruby@v1
         with:
-          serviceAccountJsonPlainText: ${{secrets.SERVICE_ACCOUNT_JSON}}
-          packageName: com.rtbishop.look4sat
-          releaseFiles: app/build/outputs/apk/release/look4sat.aab
-          track: production
-          whatsNewDirectory: fastlane/metadata/android/en-US/whatsnew
+          ruby-version: '3.4'
+
+      - name: Deploy Bundle to Google Play
+        run: |
+          gem install multi_json
+          gem install fastlane --no-document
+          AAB=$(find app/build/outputs/bundle/release -name "*.aab" | head -1)
+          echo '${{ secrets.SERVICE_ACCOUNT_JSON }}' > service_account.json
+          fastlane supply \
+            --aab "$AAB" \
+            --json_key service_account.json \
+            --package_name com.rtbishop.look4sat \
+            --track production \
+            --skip_upload_images true \
+            --skip_upload_screenshots true \
+          rm service_account.json
 
       - name: Create Release
         run: |

.gitignore

@@ -1,6 +1,9 @@
 # Built application files
 *.ap_
 
+# Hermes AI plans and metadata
+.hermes/
+
 # Files for the ART/Dalvik VM
 *.dex
 
@@ -15,6 +18,7 @@ out/
 # Gradle files
 .gradle/
 build/
+.cxx/
 
 # Local configuration file (sdk path, etc)
 local.properties
@@ -64,3 +68,4 @@ fastlane/readme.md
 /app/release/output-metadata.json
 /app/release/
 /.kotlin/sessions/
+dist/

AGENTS.md

@@ -0,0 +1,122 @@
+# Look4Sat AI Agent Instructions
+
+This is the canonical project guide for all AI assistants working on Look4Sat.
+All assistant-specific files (`CLAUDE.md`, `.github/copilot-instructions.md`) point here.
+
+---
+
+## Project Overview
+
+Look4Sat is an open-source, fully offline Android satellite tracker and pass predictor. It tracks 9000+ active
+satellites using TLE/OMM data from Celestrak/SatNOGS, calculates orbital positions via SGP4/SDP4 models, and displays
+passes relative to the user's location. Features include polar radar visualization, SSTV image decoding, satellite
+ground track mapping, and pass predictions up to 10 days ahead. No ads, no tracking, no network required after initial
+data download.
+
+## Architecture
+
+**MVI (Model-View-Intent)** with unidirectional data flow:
+- `State` data class → exposed via `StateFlow` from ViewModel
+- `Action` sealed interface → user intents dispatched to ViewModel's `onAction()`
+- Jetpack Compose UI observes state and recomposes reactively
+
+**Clean Architecture layers:**
+
+| Module               | Responsibility                                                      |
+|----------------------|---------------------------------------------------------------------|
+| `app`                | Entry point. Aggregates all modules                                 |
+| `core:data`          | Android library. Room DB, OkHttp networking, repo implementations   |
+| `core:domain`        | Pure Kotlin (JVM). Orbital math (SGP4/SDP4), models, repo contracts |
+| `core:presentation`  | Android library. Compose theme, shared UI components, NavKeys       |
+| `feature:map`        | OSMDroid map with ground tracks                                     |
+| `feature:passes`     | Pass predictions and upcoming events                                |
+| `feature:radar`      | Polar radar view of satellite positions, SSTV image decoding        |
+| `feature:satellites` | Satellite list, filtering, selection                                |
+| `feature:settings`   | User preferences                                                    |
+
+- `feature:*` modules depend only on `core:domain` + `core:presentation`. Features never depend on each other.
+
+## Build & Run
+
+```shell
+# Debug build
+./gradlew assembleDebug
+
+# Release build (minified, shrunk resources)
+./gradlew assembleRelease
+
+# Run tests
+./gradlew test
+```
+
+- **Min SDK**: 24 | **Target SDK**: 36 | **JDK**: 17
+- **Gradle**: Uses version catalog (`gradle/libs.versions.toml`) + convention plugins in `build-logic/`
+
+## Key Libraries
+
+- **Compose** (BOM 2026.05.01) + Material3 Adaptive
+- **Navigation3** (type-safe, uses `@Serializable` NavKeys)
+- **Room** (KSP code generation) for local satellite/TLE storage
+- **OkHttp** 5.x for TLE downloads
+- **OSMDroid** for map rendering
+- **Kotlin Serialization** for navigation args and data parsing
+- **Coroutines** + `StateFlow` for async/reactive patterns
+
+## Conventions
+
+- **Minimal dependencies**: Avoid adding libraries when a simple manual solution exists. Fewer deps = less maintenance.
+- **DI**: Manual — ViewModels use companion `factory()` methods with `IMainContainer` interface.
+- **Navigation**: Type-safe Compose Navigation3 with `@Serializable` data classes as nav keys.
+- **State naming**: `<Feature>State` data class + `<Feature>Action` sealed interface per feature.
+- **No feature-to-feature deps**: All cross-feature communication goes through core layers.
+- **Localization**: 7 languages (en, es, ru, si, tr, uk, zh).
+
+## Data Formats & Migration
+
+**TLE vs. OMM/CSV format:**
+
+Look4Sat supports both TLE and OMM (Orbit Mean-Elements Message) formats for backward compatibility:
+
+- **TLE format**: Traditional 3-line element format (deprecated). NORAD catalog numbers are 5-digit integers, which
+  are running out of space. Celestrak has signaled that TLE format will eventually be phased out.
+- **OMM/CSV format**: The future standard. CSV files contain the same orbital parameters as TLE but use ISO 8601
+  timestamps and support larger NORAD IDs. Celestrak and SatNOGS already provide OMM data in CSV format.
+
+**Current implementation:**
+- `DataParser.kt` handles both `parseTLEStream()` and `parseCSVStream()` seamlessly
+- TLE data is downloaded from configured sources and stored in Room database
+- When downloading satellite data, the app automatically detects format and parses accordingly
+- Both formats produce identical `OrbitalData` objects, ensuring transparent format switching
+
+**Migration path:**
+As NORAD catalog space becomes constrained, OMM/CSV will become the primary format. Look4Sat is already positioned
+to handle this transition without code changes — existing users can continue using TLE files while new sources
+transition to OMM/CSV automatically.
+
+## Code Style
+
+- Prefer **short, focused functions** — single responsibility, easy to read.
+- **Exceptions**: Composable functions and math-heavy algorithms (SGP4/SDP4) may be longer.
+- Strict code style — no dead code, no unused imports, consistent formatting.
+
+## Roadmap
+
+- **KMP migration**: `core:domain` is to become a fully shareable KMM module. Keep it pure Kotlin/JVM.
+
+## Gotchas
+
+- Orbital math lives in `core:domain/predict/` — it's dense vector math (SGP4/SDP4). Tread carefully.
+- TLE/OMM data must be refreshed weekly for accurate predictions (satellite orbits decay). TLE format is legacy and
+  will eventually be deprecated in favor of OMM/CSV as NORAD catalog numbers approach the 5-digit limit.
+- SSTV decoding in `feature:radar` is experimental; image quality depends on signal strength during satellite pass.
+- `build-logic/convention/` contains all shared Gradle configuration — edit there, not in individual modules.
+- ProGuard is enabled for release builds — don't add reflection-based libs or any other dependencies without asking.
+
+## Copilot Working Mode: Code-Only
+
+- Default to code changes only. Provide explanations in chat only.
+- If documentation seems useful, ask first before creating files.
+- Do NOT create any `.md` documentation files unless explicitly requested.
+- Do NOT add README, guides, summaries, migration notes, or how-to files unless asked.
+- Prefer minimal diffs focused on requested implementation.
+- Default validation is static checks (`get_errors`). Do NOT run Gradle compile/test tasks unless explicitly requested.

CLAUDE.md

@@ -0,0 +1,5 @@
+# CLAUDE.md
+
+Read `AGENTS.md` first, then follow the instructions there.
+
+`AGENTS.md` contains the architecture, module boundaries, implementation details, conventions, and gotchas.

README.md

@@ -1,35 +1,38 @@
-# Look4Sat: Satellite tracker
+# Look4Sat-BA7OPF
 
-[![Look4Sat CI](https://github.com/rt-bishop/Look4Sat/actions/workflows/release.yml/badge.svg)](https://github.com/rt-bishop/Look4Sat/actions/workflows/release.yml)
+[![Release](https://img.shields.io/github/v/release/atsunatsu/Look4Sat)](https://github.com/atsunatsu/Look4Sat/releases)
 
-[<img src="https://play.google.com/intl/en_gb/badges/static/images/badges/en_badge_web_generic.png" alt="Get it on Google Play" height="80">](https://play.google.com/store/apps/details?id=com.rtbishop.look4sat)
-[<img src="https://fdroid.gitlab.io/artwork/badge/get-it-on.png" alt="Get it on F-Droid" height="80">](https://f-droid.org/packages/com.rtbishop.look4sat/)
+**BA7OPF 定制版** — 基于 [rt-bishop/Look4Sat](https://github.com/rt-bishop/Look4Sat) 的业余无线电卫星追踪器，增加了线性卫星频率计算器等功能。
 
-### Radio satellite tracker and pass predictor for Android, inspired by Gpredict
+## 本仓库特色功能
 
-<p float="left">
-<img src="fastlane/metadata/android/en-US/images/phoneScreenshots/1.png" width="192"/>
-<img src="fastlane/metadata/android/en-US/images/phoneScreenshots/2.png" width="192"/>
-<img src="fastlane/metadata/android/en-US/images/phoneScreenshots/3.png" width="192"/>
-<img src="fastlane/metadata/android/en-US/images/phoneScreenshots/4.png" width="192">
-</p>
+- **双站过境匹配（Mutual Pass）** — 输入友台经纬度/网格，筛选双方同时可见的卫星过境，在地图上同时显示双方仰角曲线和地面轨迹，支持一键跳转雷达页查看详情
+- **线性卫星转发器频率计算器** — 在雷达页的 Calculator 标签页中，支持 TX/RX 双向多普勒频率计算，以及下行频率偏移（offset）输入，方便操作带偏移的线性卫星
+- **CW 解码器** — 集成 Morse Expert 解码引擎，支持瀑布图、实时解码文本
+- **Passband 模式** — 支持通过位置滑块（Passband）自动计算 TX/RX 频率，避免切换时跳变
+- **AMSAT 状态页** — 实时查看卫星的业余无线电转发器状态（开启/关闭/待机），支持 72 小时历史记录回放
+- **中文界面优化** — 翻译修正、UI 布局调整，系统语言自动切换
 
-### Track satellite passes with ease!
+## 上游仓库
 
-Thanks to [Celestrak](https://celestrak.com/) and [SatNOGS](https://satnogs.org/) you have access to over 9000 active satellites.\
-You can search the entire database by NORAD Catalog Number or the satellite's name.
+本仓库是 [rt-bishop/Look4Sat](https://github.com/rt-bishop/Look4Sat) 的分支，上游仓库的原始功能包括：
 
-Orbital positions and passes are calculated relative to your location.\
-To get reliable data make sure to set the station position via the app Settings.
+- 基于 Celestrak / SatNOGS 数据的 9000+ 活跃卫星追踪
+- SGP4/SDP4 轨道预测，10 天过境预报
+- 极坐标雷达图、地面轨迹图
+- SSTV 图像解码
+- 无广告、无跟踪、完全离线
 
-The application is built using Kotlin, Coroutines, Jetpack Compose and Navigation.\
-It is now and always will be completely ad-free and open-source.
+## 许可证
 
-## Main features:
+GNU General Public License v3.0。详见 [LICENSE](LICENSE)。
 
-*  Predicting satellite positions and passes for up to 10 days
-*  Showing the list of currently active and upcoming satellite passes
-*  Showing the active pass progress, polar trajectory and transceivers info
-*  Showing the satellite positional data, footprint and ground track on the map
-*  Custom TLE satellite data import is available via Three Line Element .txt files
-*  Offline first: calculations are made offline. Weekly TLE data update is recommended.
+## Star History
+
+<a href="https://star-history.dera.page/#atsunatsu/Look4Sat&type=timeline&legend=top-left">
+ <picture>
+   <source media="(prefers-color-scheme: dark)" srcset="https://star-history.dera.page/svg?repos=atsunatsu/Look4Sat&type=timeline&theme=dark&legend=top-left" />
+   <source media="(prefers-color-scheme: light)" srcset="https://star-history.dera.page/svg?repos=atsunatsu/Look4Sat&type=timeline&legend=top-left" />
+   <img alt="Star History Chart" src="https://star-history.dera.page/svg?repos=atsunatsu/Look4Sat&type=timeline&legend=top-left" />
+ </picture>
+</a>

app/build.gradle.kts

@@ -1,3 +1,36 @@
+import java.io.FileInputStream
+import java.util.Properties
+
 plugins {
-    alias(libs.plugins.convention.androidAppPlugin)
+    alias(libs.plugins.convention.applicationPlugin)
 }
+
+// Release signing credentials live in local.properties (gitignored) or
+// environment variables — never hardcode passwords in VCS.
+val releaseProps = Properties().apply {
+    val propsFile = rootProject.file("local.properties")
+    if (propsFile.exists()) FileInputStream(propsFile).use { load(it) }
+}
+fun releaseCred(name: String): String =
+    releaseProps.getProperty(name) ?: System.getenv(name) ?: ""
+
+android {
+    namespace = libs.versions.packageName.get()
+    defaultConfig {
+        applicationId = "cn.ba7opf.look4sat"
+        ndk { abiFilters.add("armeabi-v7a") }
+    }
+    signingConfigs {
+        create("release") {
+            storeFile = file(System.getProperty("user.home") + "/my-release-key.jks")
+            storePassword = releaseCred("RELEASE_STORE_PASSWORD")
+            keyAlias = releaseCred("RELEASE_KEY_ALIAS").ifEmpty { "look4sat" }
+            keyPassword = releaseCred("RELEASE_KEY_PASSWORD")
+        }
+    }
+    buildTypes {
+        release {
+            signingConfig = signingConfigs.getByName("release")
+        }
+    }
+}

app/src/main/AndroidManifest.xml

@@ -2,6 +2,7 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
 
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.ACCESS_LOCAL_NETWORK" />
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
     <uses-permission
@@ -11,26 +12,49 @@
     <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
     <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
     <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.RECORD_AUDIO" />
+    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES" />
 
     <application
         android:name=".MainApplication"
+        android:allowBackup="false"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
+        android:networkSecurityConfig="@xml/network_security_config"
         android:roundIcon="@mipmap/ic_launcher_round">
 
         <activity
             android:name=".MainActivity"
             android:exported="true"
+            android:screenOrientation="portrait"
             android:theme="@style/Theme.Look4Sat.SplashScreen">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
+<!--            <intent-filter android:autoVerify="true">-->
+<!--                <action android:name="android.intent.action.VIEW" />-->
+<!--                <category android:name="android.intent.category.DEFAULT" />-->
+<!--                <category android:name="android.intent.category.BROWSABLE" />-->
+<!--                <data android:scheme="https" />-->
+<!--                <data android:host="github.com" />-->
+<!--                <data android:pathPattern="/rt-bishop/Look4Sat/passes.*" />-->
+<!--            </intent-filter>-->
         </activity>
 
         <meta-data
             android:name="android.telephony.PROPERTY_SATELLITE_DATA_OPTIMIZED"
             android:value="com.rtbishop.look4sat" />
 
+        <provider
+            android:name="androidx.core.content.FileProvider"
+            android:authorities="${applicationId}.fileprovider"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/file_paths" />
+        </provider>
+
     </application>
 </manifest>

app/src/main/java/com/rtbishop/look4sat/MainActivity.kt

@@ -19,12 +19,21 @@ package com.rtbishop.look4sat
 
 import android.content.Context
 import android.content.res.Configuration
+import android.graphics.ColorMatrix
+import android.graphics.ColorMatrixColorFilter
+import android.graphics.Paint
 import android.os.Bundle
+import android.view.View
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
 import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
+import androidx.lifecycle.lifecycleScope
+import com.rtbishop.look4sat.core.domain.repository.IContainerProvider
 import com.rtbishop.look4sat.core.presentation.MainTheme
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
 
 class MainActivity : ComponentActivity() {
 
@@ -38,8 +47,37 @@ class MainActivity : ComponentActivity() {
         installSplashScreen()
         enableEdgeToEdge()
         super.onCreate(savedInstanceState)
+        observeNightFilterState()
         setContent {
-            MainTheme(isDarkTheme = true) { MainScreen() }
+            MainTheme(isDarkTheme = true) { NavRoot() }
+        }
+    }
+
+    private fun observeNightFilterState() {
+        val mainContainer = (applicationContext as IContainerProvider).getMainContainer()
+        lifecycleScope.launch {
+            mainContainer.settingsRepo.otherSettings
+                .map { it.stateOfNightMode }
+                .distinctUntilChanged()
+                .collect { nightMode -> applyNightFilter(nightMode) }
+        }
+    }
+
+    private fun applyNightFilter(enabled: Boolean) {
+        if (enabled) {
+            val nightMatrix = ColorMatrix(
+                floatArrayOf(
+                    1f, 0f, 0f, 0f, 0f,   // R → R
+                    0f, 0f, 0f, 0f, 0f,   // G → 0
+                    0f, 0f, 0f, 0f, 0f,   // B → 0
+                    0f, 0f, 0f, 1f, 0f    // A → A
+                )
+            )
+            window.decorView.setLayerType(View.LAYER_TYPE_HARDWARE, Paint().apply {
+                colorFilter = ColorMatrixColorFilter(nightMatrix)
+            })
+        } else {
+            window.decorView.setLayerType(View.LAYER_TYPE_NONE, null)
         }
     }
 }

app/src/main/java/com/rtbishop/look4sat/MainApplication.kt

@@ -17,7 +17,10 @@
  */
 package com.rtbishop.look4sat
 
+import android.app.Activity
 import android.app.Application
+import android.app.Application.ActivityLifecycleCallbacks
+import android.os.Bundle
 import com.rtbishop.look4sat.core.data.injection.MainContainer
 import com.rtbishop.look4sat.core.domain.repository.IContainerProvider
 import com.rtbishop.look4sat.core.domain.repository.IMainContainer
@@ -35,12 +38,37 @@ class MainApplication : Application(), IContainerProvider {
     override fun onCreate() {
         super.onCreate()
         container = MainContainer(this)
+        clearAmSatCacheOnAppBackground()
         // trigger automatic update every 48 hours
         container.appScope.launch { checkAutoUpdate() }
         // load satellite data on every app start
         container.appScope.launch { container.satelliteRepo.initRepository() }
     }
 
+    private fun clearAmSatCacheOnAppBackground() {
+        registerActivityLifecycleCallbacks(object : ActivityLifecycleCallbacks {
+            private var startedActivityCount = 0
+
+            override fun onActivityStarted(activity: Activity) {
+                if (startedActivityCount == 0) {
+                    container.appScope.launch { container.amSatRepo.prefetchStatus() }
+                }
+                startedActivityCount += 1
+            }
+
+            override fun onActivityStopped(activity: Activity) {
+                startedActivityCount = (startedActivityCount - 1).coerceAtLeast(0)
+                if (startedActivityCount == 0) container.amSatRepo.clearStatusCache()
+            }
+
+            override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) = Unit
+            override fun onActivityResumed(activity: Activity) = Unit
+            override fun onActivityPaused(activity: Activity) = Unit
+            override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) = Unit
+            override fun onActivityDestroyed(activity: Activity) = Unit
+        })
+    }
+
     private suspend fun checkAutoUpdate(timeNow: Long = System.currentTimeMillis()) {
         if (container.settingsRepo.otherSettings.value.stateOfAutoUpdate) {
             val timeDelta = timeNow - container.settingsRepo.databaseState.value.updateTimestamp

app/src/main/java/com/rtbishop/look4sat/MainScreen.kt

@@ -17,74 +17,297 @@
  */
 package com.rtbishop.look4sat
 
+import androidx.compose.animation.core.LinearEasing
+import androidx.compose.animation.core.RepeatMode
+import androidx.compose.animation.core.animateFloat
+import androidx.compose.animation.core.infiniteRepeatable
+import androidx.compose.animation.core.rememberInfiniteTransition
 import androidx.compose.animation.core.tween
 import androidx.compose.animation.fadeIn
 import androidx.compose.animation.fadeOut
+import androidx.compose.animation.slideInHorizontally
+import androidx.compose.animation.slideOutHorizontally
+import androidx.compose.animation.togetherWith
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.material3.adaptive.navigationsuite.NavigationSuiteDefaults
 import androidx.compose.material3.adaptive.navigationsuite.NavigationSuiteScaffold
 import androidx.compose.material3.adaptive.navigationsuite.NavigationSuiteType
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableIntStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
-import androidx.navigation.NavHostController
-import androidx.navigation.compose.NavHost
-import androidx.navigation.compose.currentBackStackEntryAsState
-import androidx.navigation.compose.rememberNavController
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import androidx.lifecycle.ViewModelStoreOwner
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import androidx.lifecycle.viewmodel.compose.viewModel
+import androidx.lifecycle.viewmodel.navigation3.rememberViewModelStoreNavEntryDecorator
+import androidx.navigation3.runtime.entryProvider
+import androidx.navigation3.runtime.rememberNavBackStack
+import androidx.navigation3.runtime.rememberSaveableStateHolderNavEntryDecorator
+import androidx.navigation3.ui.NavDisplay
+import com.rtbishop.look4sat.core.domain.repository.IContainerProvider
+import com.rtbishop.look4sat.core.domain.repository.MutualPassData
+import com.rtbishop.look4sat.core.presentation.DeeplinkResolver
+import com.rtbishop.look4sat.core.presentation.ElevationThresholds
+import com.rtbishop.look4sat.core.presentation.LocalElevationThresholds
+import com.rtbishop.look4sat.core.presentation.RadarDestination
 import com.rtbishop.look4sat.core.presentation.Screen
 import com.rtbishop.look4sat.core.presentation.hasEnoughHeight
 import com.rtbishop.look4sat.core.presentation.hasEnoughWidth
-import com.rtbishop.look4sat.feature.map.mapDestination
-import com.rtbishop.look4sat.feature.passes.passesDestination
-import com.rtbishop.look4sat.feature.radar.radarDestination
-import com.rtbishop.look4sat.feature.satellites.satellitesDestination
-import com.rtbishop.look4sat.feature.settings.settingsDestination
+import com.rtbishop.look4sat.feature.map.MapDestination
+import com.rtbishop.look4sat.feature.mutual.MutualScreen
+import com.rtbishop.look4sat.feature.mutual.MutualViewModel
+import com.rtbishop.look4sat.feature.passes.PassesDestination
+import com.rtbishop.look4sat.feature.radar.RadarDestination
+import com.rtbishop.look4sat.feature.satellites.SatellitesDestination
+import com.rtbishop.look4sat.feature.settings.SettingsDestination
+import com.rtbishop.look4sat.feature.status.SatStatusDestination
 
 @Composable
-fun MainScreen(navController: NavHostController = rememberNavController()) {
-    val items = listOf(Screen.Satellites, Screen.Passes, Screen.Radar, Screen.Map, Screen.Settings)
-    val currentDestination = navController.currentBackStackEntryAsState().value?.destination?.route
-    val startDestination = Screen.Passes.route
-    NavigationSuiteScaffold(
-        navigationSuiteItems = {
-            items.forEach {
-                item(
-                    icon = { Icon(painterResource(it.iconResId), stringResource(it.titleResId)) },
-                    label = { Text(stringResource(it.titleResId)) },
-                    selected = currentDestination?.contains(it.route) ?: false,
-                    onClick = {
-                        if (currentDestination?.contains(it.route) ?: false) return@item
-                        navController.navigate(it.route) {
-                            popUpTo(startDestination) { saveState = false }
-                            launchSingleTop = true
-                            restoreState = false
-                        }
-                    })
+fun NavRoot(deeplink: String? = null) {
+    val rootBackStack = rememberNavBackStack(Screen.Passes)
+    val deeplinkResolver = DeeplinkResolver()
+    var openMapRequest by remember { mutableIntStateOf(0) }
+    LaunchedEffect(deeplink) {
+        deeplink?.let { rootBackStack.add(deeplinkResolver.resolve(it)) }
+    }
+    val navigateBack: () -> Unit = { rootBackStack.removeLastOrNull() }
+    val navigateToRadar: () -> Unit = { rootBackStack.add(RadarDestination) }
+    val navigateToMap: () -> Unit = {
+        while (rootBackStack.size > 1) rootBackStack.removeAt(rootBackStack.size - 1)
+        openMapRequest += 1
+    }
+    // Incoming screen slides in from the right, outgoing drifts left at 1/3 speed (API35+ style)
+    val pushTransition = slideInHorizontally(tween(300)) { it } togetherWith
+        slideOutHorizontally(tween(300)) { -it / 3 }
+    // Reverse: outgoing slides out to the right, incoming drifts in from the left
+    val popTransition = slideInHorizontally(tween(300)) { -it / 3 } togetherWith
+        slideOutHorizontally(tween(300)) { it }
+    NavDisplay(
+        modifier = Modifier.fillMaxSize(),
+        backStack = rootBackStack,
+        onBack = navigateBack,
+        transitionSpec = { pushTransition },
+        popTransitionSpec = { popTransition },
+        predictivePopTransitionSpec = { popTransition },
+        entryDecorators = listOf(
+            rememberSaveableStateHolderNavEntryDecorator(),
+            rememberViewModelStoreNavEntryDecorator()
+        ),
+        entryProvider = entryProvider {
+            entry<Screen.Passes> {
+                MainScreen(
+                    navigateToRadar = navigateToRadar,
+                    openMapRequest = openMapRequest,
+                    onOpenMapRequestHandled = { openMapRequest = 0 }
+                )
+            }
+            entry<RadarDestination> {
+                Surface(
+                    modifier = Modifier.fillMaxSize(),
+                    color = MaterialTheme.colorScheme.background
+                ) {
+                    RadarDestination(navigateUp = navigateBack, navigateToMap = navigateToMap)
+                }
             }
-        }, navigationSuiteColors = NavigationSuiteDefaults.colors(
-            navigationRailContainerColor = MaterialTheme.colorScheme.surfaceContainer
-        ), layoutType = when {
-            !hasEnoughHeight() && hasEnoughWidth() -> NavigationSuiteType.NavigationRail
-            !hasEnoughWidth() -> NavigationSuiteType.ShortNavigationBarCompact
-            else -> NavigationSuiteType.ShortNavigationBarMedium
         }
+    )
+}
+
+@Composable
+fun MainScreen(
+    navigateToRadar: () -> Unit = {},
+    openMapRequest: Int = 0,
+    onOpenMapRequestHandled: () -> Unit = {}
+) {
+    val backStack = rememberNavBackStack(Screen.Passes)
+    val currentKey = backStack.lastOrNull()
+    val navigateBack: () -> Unit = { backStack.removeLastOrNull() }
+    val navigateToMap: () -> Unit = {
+        while (backStack.size > 1) backStack.removeAt(backStack.size - 1)
+        backStack.add(Screen.Map)
+    }
+    LaunchedEffect(openMapRequest) {
+        if (openMapRequest > 0) {
+            navigateToMap()
+            onOpenMapRequestHandled()
+        }
+    }
+    val fadeTransition = fadeIn(animationSpec = tween(350)) togetherWith fadeOut(animationSpec = tween(350))
+    val navItems = listOf(Screen.Satellites, Screen.Passes, Screen.AMSAT, Screen.Mutual, Screen.Settings)
+
+    val context = LocalContext.current
+    val container = (context.applicationContext as IContainerProvider).getMainContainer()
+    val trackingState by container.radioTrackingService.state.collectAsStateWithLifecycle()
+    val otherSettings by container.settingsRepo.otherSettings.collectAsStateWithLifecycle()
+    // Activity-scoped so the mutual query results survive navigation to Radar and back
+    val mutualViewModel: MutualViewModel = viewModel(
+        viewModelStoreOwner = context as ViewModelStoreOwner,
+        factory = MutualViewModel.factory(container)
+    )
+
+    CompositionLocalProvider(
+        LocalElevationThresholds provides ElevationThresholds(
+            low = otherSettings.lowElevation,
+            high = otherSettings.highElevation
+        )
     ) {
-        NavHost(
-            navController = navController,
-            startDestination = startDestination,
-            enterTransition =  { fadeIn(animationSpec = tween(350)) },
-            exitTransition = { fadeOut(animationSpec = tween(350)) }
-        ) {
-            satellitesDestination { navController.navigateUp() }
-            passesDestination { catNum: Int, aosTime: Long ->
-                val radarRoute = "${Screen.Radar.route}?catNum=${catNum}&aosTime=${aosTime}"
-                navController.navigate(radarRoute)
+        NavigationSuiteScaffold(
+            navigationSuiteItems = {
+                navItems.forEach { screen ->
+                    val isSelected = when (currentKey) {
+                        is Screen.Satellites -> screen is Screen.Satellites
+                        is Screen.Passes -> screen is Screen.Passes
+                        is Screen.Map -> screen is Screen.Passes
+                        is Screen.AMSAT -> screen is Screen.AMSAT
+                        is Screen.Mutual -> screen is Screen.Mutual
+                        is Screen.Settings -> screen is Screen.Settings
+                        else -> false
+                    }
+                    item(
+                        icon = { Icon(painterResource(screen.iconResId), stringResource(screen.titleResId)) },
+                        label = { Text(stringResource(screen.titleResId)) },
+                        selected = isSelected,
+                        onClick = {
+                            if (isSelected && !(currentKey is Screen.Map && screen is Screen.Passes)) return@item
+                            while (backStack.size > 1) backStack.removeAt(backStack.size - 1)
+                            if (screen !is Screen.Passes) backStack.add(screen)
+                        }
+                    )
+                }
+            },
+            navigationSuiteColors = NavigationSuiteDefaults.colors(
+                navigationRailContainerColor = MaterialTheme.colorScheme.surfaceContainer
+            ),
+            layoutType = when {
+                !hasEnoughHeight() && hasEnoughWidth() -> NavigationSuiteType.NavigationRail
+                !hasEnoughWidth() -> NavigationSuiteType.ShortNavigationBarCompact
+                else -> NavigationSuiteType.ShortNavigationBarMedium
+            }
+        ) {
+            Column {
+                NavDisplay(
+                    backStack = backStack,
+                    modifier = Modifier.weight(1f),
+                    onBack = navigateBack,
+                    transitionSpec = { fadeTransition },
+                    popTransitionSpec = { fadeTransition },
+                    predictivePopTransitionSpec = { fadeTransition },
+                    entryDecorators = listOf(
+                        // Required for saving Compose state per entry
+                        rememberSaveableStateHolderNavEntryDecorator(),
+                        // Required for ViewModel scoping per entry
+                        rememberViewModelStoreNavEntryDecorator()
+                    ),
+                    entryProvider = entryProvider {
+                        entry<Screen.Satellites> {
+                            SatellitesDestination(navigateUp = navigateBack)
+                        }
+                        entry<Screen.Passes> {
+                            PassesDestination(
+                                navigateToRadar = { catNum, aosTime ->
+                                    container.setMutualPassData(MutualPassData())
+                                    container.satelliteRepo.selectPass(catNum, aosTime)
+                                    navigateToRadar()
+                                },
+                                navigateToMap = navigateToMap
+                            )
+                        }
+                        entry<Screen.Map> {
+                            MapDestination()
+                        }
+                        entry<Screen.Mutual> {
+                            MutualScreen(
+                                viewModel = mutualViewModel,
+                                navigateToRadar = { catNum, aosTime, pass ->
+                                    container.setMutualPassData(pass ?: MutualPassData())
+                                    container.satelliteRepo.selectPass(catNum, aosTime)
+                                    navigateToRadar()
+                                }
+                            )
+                        }
+                        entry<Screen.AMSAT> { SatStatusDestination() }
+                        entry<Screen.Settings> {
+                            SettingsDestination()
+                        }
+                    }
+                )
+                // Radio tracking status banner
+                if (trackingState.isActive) {
+                    val infiniteTransition = rememberInfiniteTransition(label = "trackingPulse")
+                    val alpha by infiniteTransition.animateFloat(
+                        initialValue = 1f, targetValue = 0.4f,
+                        animationSpec = infiniteRepeatable(
+                            animation = tween(1000, easing = LinearEasing),
+                            repeatMode = RepeatMode.Reverse
+                        ), label = "pulseAlpha"
+                    )
+                    Row(
+                        verticalAlignment = Alignment.CenterVertically,
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .background(MaterialTheme.colorScheme.primaryContainer)
+                            .clickable {
+                                val pass = trackingState.currentPass
+                                if (pass != null) {
+                                    container.setMutualPassData(MutualPassData())
+                                    container.satelliteRepo.selectPass(pass.catNum, pass.aosTime)
+                                    navigateToRadar()
+                                }
+                            }
+                            .padding(horizontal = 12.dp, vertical = 6.dp)
+                    ) {
+                        Box(
+                            modifier = Modifier
+                                .size(8.dp)
+                                .clip(CircleShape)
+                                .background(Color(0xFF4CAF50).copy(alpha = alpha))
+                        )
+                        Spacer(modifier = Modifier.width(8.dp))
+                        Text(
+                            text = "Tracking: ${trackingState.currentPass?.name ?: ""}",
+                            fontSize = 13.sp,
+                            fontWeight = FontWeight.Medium,
+                            color = MaterialTheme.colorScheme.onPrimaryContainer,
+                            modifier = Modifier.weight(1f)
+                        )
+                        val txOk = if (trackingState.txConnected) "TX" else ""
+                        val rxOk = if (trackingState.rxConnected) "RX" else ""
+                        Text(
+                            text = listOf(txOk, rxOk).filter { it.isNotBlank() }.joinToString("/"),
+                            fontSize = 12.sp,
+                            color = MaterialTheme.colorScheme.onPrimaryContainer
+                        )
+                    }
+                }
             }
-            radarDestination { navController.navigateUp() }
-            mapDestination()
-            settingsDestination()
         }
     }
 }

app/src/main/res/xml/file_paths.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<paths xmlns:android="http://schemas.android.com/apk/res/android">
+    <cache-path name="updates" path="." />
+</paths>

app/src/main/res/xml/network_security_config.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<network-security-config>
+    <base-config cleartextTrafficPermitted="true" />
+</network-security-config>

build-logic/convention/build.gradle.kts

@@ -24,25 +24,25 @@ group = "com.rtbishop.look4sat.build_logic.convention"
 
 gradlePlugin {
     plugins {
-        register("androidAppPlugin") {
-            id = libs.plugins.convention.androidAppPlugin.get().pluginId
-            implementationClass = "com.rtbishop.look4sat.convention.AndroidAppPlugin"
+        register("applicationPlugin") {
+            id = libs.plugins.convention.applicationPlugin.get().pluginId
+            implementationClass = "com.rtbishop.look4sat.convention.ApplicationPlugin"
         }
-        register("androidLibraryPlugin") {
-            id = libs.plugins.convention.androidLibraryPlugin.get().pluginId
-            implementationClass = "com.rtbishop.look4sat.convention.AndroidLibraryPlugin"
+        register("coreDataPlugin") {
+            id = libs.plugins.convention.coreDataPlugin.get().pluginId
+            implementationClass = "com.rtbishop.look4sat.convention.CoreDataPlugin"
         }
-        register("composeFeaturePlugin") {
-            id = libs.plugins.convention.composeFeaturePlugin.get().pluginId
-            implementationClass = "com.rtbishop.look4sat.convention.ComposeFeaturePlugin"
+        register("coreDomainPlugin") {
+            id = libs.plugins.convention.coreDomainPlugin.get().pluginId
+            implementationClass = "com.rtbishop.look4sat.convention.CoreDomainPlugin"
         }
-        register("composeLibraryPlugin") {
-            id = libs.plugins.convention.composeLibraryPlugin.get().pluginId
-            implementationClass = "com.rtbishop.look4sat.convention.ComposeLibraryPlugin"
+        register("corePresentationPlugin") {
+            id = libs.plugins.convention.corePresentationPlugin.get().pluginId
+            implementationClass = "com.rtbishop.look4sat.convention.CorePresentationPlugin"
         }
-        register("kotlinLibraryPlugin") {
-            id = libs.plugins.convention.kotlinLibraryPlugin.get().pluginId
-            implementationClass = "com.rtbishop.look4sat.convention.KotlinLibraryPlugin"
+        register("featurePlugin") {
+            id = libs.plugins.convention.featurePlugin.get().pluginId
+            implementationClass = "com.rtbishop.look4sat.convention.FeaturePlugin"
         }
     }
 }

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/AndroidAppPlugin.kt

@@ -1,46 +0,0 @@
-/*
- * Look4Sat. Amateur radio satellite tracker and pass predictor.
- * Copyright (C) 2019-2026 Arty Bishop and contributors.
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
-package com.rtbishop.look4sat.convention
-
-import org.gradle.api.Plugin
-import org.gradle.api.Project
-import org.gradle.kotlin.dsl.dependencies
-
-@Suppress("Unused")
-internal class AndroidAppPlugin : Plugin<Project> {
-    override fun apply(target: Project) {
-        with(target) {
-            setupAndroidApplication()
-            setupComposeFeature()
-            setupKotlinToolchain()
-            setupAndroidTestDependencies()
-            setupTestDependencies()
-            dependencies {
-                IMPLEMENTATION(project(":core:data"))
-                IMPLEMENTATION(project(":core:domain"))
-                IMPLEMENTATION(project(":core:presentation"))
-                IMPLEMENTATION(project(":feature:map"))
-                IMPLEMENTATION(project(":feature:passes"))
-                IMPLEMENTATION(project(":feature:radar"))
-                IMPLEMENTATION(project(":feature:satellites"))
-                IMPLEMENTATION(project(":feature:settings"))
-                IMPLEMENTATION(libs.androidx.core.splashscreen)
-            }
-        }
-    }
-}

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/ApplicationPlugin.kt

@@ -0,0 +1,47 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.convention
+
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.kotlin.dsl.dependencies
+
+@Suppress("Unused")
+internal class ApplicationPlugin : Plugin<Project> {
+    override fun apply(target: Project) = with(target) {
+        setupAndroidApp()
+        setupCompose()
+        setupKotlin()
+        dependencies {
+            implementation(project(":core:data"))
+            implementation(project(":core:domain"))
+            implementation(project(":core:presentation"))
+            implementation(project(":feature:map"))
+            implementation(project(":feature:mutual"))
+            implementation(project(":feature:passes"))
+            implementation(project(":feature:radar"))
+            implementation(project(":feature:satellites"))
+            implementation(project(":feature:settings"))
+            implementation(project(":feature:status"))
+            implementation(libs.androidx.core.splashscreen)
+            implementation(libs.compose.material3.adaptive)
+            implementation(libs.compose.navigation3)
+            androidTestImplementation(libs.bundles.androidTest)
+        }
+    }
+}

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/CoreDataPlugin.kt

@@ -22,25 +22,19 @@ import org.gradle.api.Project
 import org.gradle.kotlin.dsl.dependencies
 
 @Suppress("Unused")
-internal class AndroidLibraryPlugin : Plugin<Project> {
-    override fun apply(target: Project) {
-        with(target) {
-            with(pluginManager) {
-                alias(libs.plugins.google.ksp)
-            }
-            setupCommonLibrary()
-            setupKotlinToolchain()
-            setupAndroidTestDependencies()
-            setupTestDependencies()
-            dependencies {
-                IMPLEMENTATION(project(":core:domain"))
-                IMPLEMENTATION(libs.androidx.core.ktx)
-                IMPLEMENTATION(libs.androidx.room.asProvider())
-                IMPLEMENTATION(libs.androidx.room.runtime)
-                KSP(libs.androidx.room.compiler)
-                IMPLEMENTATION(libs.other.coroutines)
-                IMPLEMENTATION(libs.other.okhttp)
-            }
+internal class CoreDataPlugin : Plugin<Project> {
+    override fun apply(target: Project) = with(target) {
+        applyPlugin(libs.plugins.google.ksp)
+        setupAndroidLib()
+        setupKotlin()
+        dependencies {
+            implementation(project(":core:domain"))
+            implementation(libs.androidx.core.ktx)
+            implementation(libs.androidx.room)
+            implementation(libs.androidx.room.runtime)
+            ksp(libs.androidx.room.compiler)
+            implementation(libs.kotlin.coroutines)
+            implementation(libs.other.okhttp)
         }
     }
 }

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/CoreDomainPlugin.kt

@@ -22,18 +22,14 @@ import org.gradle.api.Project
 import org.gradle.kotlin.dsl.dependencies
 
 @Suppress("Unused")
-internal class KotlinLibraryPlugin : Plugin<Project> {
-    override fun apply(target: Project) {
-        with(target) {
-            with(pluginManager) {
-                alias(libs.plugins.kotlin.jvm)
-            }
-            setupKotlinToolchain()
-            setupTestDependencies()
-            dependencies {
-                IMPLEMENTATION(libs.other.coroutines)
-                IMPLEMENTATION(libs.other.json)
-            }
+internal class CoreDomainPlugin : Plugin<Project> {
+    override fun apply(target: Project) = with(target) {
+        applyPlugin(libs.plugins.kotlin.jvm)
+        applyPlugin(libs.plugins.kotlin.serialization)
+        setupKotlin()
+        dependencies {
+            implementation(libs.kotlin.coroutines)
+            implementation(libs.kotlin.serialization)
         }
     }
 }

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/CorePresentationPlugin.kt

@@ -22,18 +22,17 @@ import org.gradle.api.Project
 import org.gradle.kotlin.dsl.dependencies
 
 @Suppress("Unused")
-internal class ComposeLibraryPlugin : Plugin<Project> {
-    override fun apply(target: Project) {
-        with(target) {
-            setupCommonLibrary()
-            setupComposeFeature()
-            setupKotlinToolchain()
-            setupAndroidTestDependencies()
-            setupTestDependencies()
-            dependencies {
-                IMPLEMENTATION(project(":core:domain"))
-                IMPLEMENTATION(libs.androidx.core.splashscreen)
-            }
+internal class CorePresentationPlugin : Plugin<Project> {
+    override fun apply(target: Project) = with(target) {
+        applyPlugin(libs.plugins.kotlin.serialization)
+        setupAndroidLib()
+        setupCompose()
+        setupKotlin()
+        dependencies {
+            implementation(project(":core:domain"))
+            implementation(libs.androidx.core.splashscreen)
+            implementation(libs.kotlin.serialization)
+            implementation(libs.compose.material3.adaptive)
         }
     }
 }

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/FeaturePlugin.kt

@@ -22,18 +22,14 @@ import org.gradle.api.Project
 import org.gradle.kotlin.dsl.dependencies
 
 @Suppress("Unused")
-internal class ComposeFeaturePlugin : Plugin<Project> {
-    override fun apply(target: Project) {
-        with(target) {
-            setupCommonLibrary()
-            setupComposeFeature()
-            setupKotlinToolchain()
-            setupAndroidTestDependencies()
-            setupTestDependencies()
-            dependencies {
-                IMPLEMENTATION(project(":core:domain"))
-                IMPLEMENTATION(project(":core:presentation"))
-            }
+internal class FeaturePlugin : Plugin<Project> {
+    override fun apply(target: Project) = with(target) {
+        setupAndroidLib()
+        setupCompose()
+        setupKotlin()
+        dependencies {
+            implementation(project(":core:domain"))
+            implementation(project(":core:presentation"))
         }
     }
 }

build-logic/convention/src/main/java/com/rtbishop/look4sat/convention/PluginSetupUtils.kt

@@ -21,7 +21,7 @@ import com.android.build.api.dsl.ApplicationExtension
 import com.android.build.api.dsl.CommonExtension
 import org.gradle.accessors.dm.LibrariesForLibs
 import org.gradle.api.Project
-import org.gradle.api.plugins.PluginManager
+import org.gradle.api.artifacts.dsl.DependencyHandler
 import org.gradle.api.provider.Provider
 import org.gradle.kotlin.dsl.accessors.runtime.extensionOf
 import org.gradle.kotlin.dsl.configure
@@ -29,23 +29,30 @@ import org.gradle.kotlin.dsl.dependencies
 import org.gradle.plugin.use.PluginDependency
 import org.jetbrains.kotlin.gradle.dsl.kotlinExtension
 
-internal const val ANDROID_TEST_IMPLEMENTATION = "androidTestImplementation"
-internal const val DEBUG_IMPLEMENTATION = "debugImplementation"
-internal const val IMPLEMENTATION = "implementation"
-internal const val KSP = "ksp"
-internal const val TEST_IMPLEMENTATION = "testImplementation"
-
 internal val Project.libs
     get(): LibrariesForLibs = extensionOf(this, "libs") as LibrariesForLibs
 
-internal fun PluginManager.alias(notation: Provider<PluginDependency>) {
-    apply(notation.get().pluginId)
+internal fun Project.applyPlugin(notation: Provider<PluginDependency>) {
+    pluginManager.apply(notation.get().pluginId)
 }
 
-internal fun Project.setupAndroidApplication() {
-    with(pluginManager) {
-        alias(libs.plugins.android.application)
-    }
+internal fun DependencyHandler.implementation(dependencyNotation: Any) =
+    add("implementation", dependencyNotation)
+
+internal fun DependencyHandler.debugImplementation(dependencyNotation: Any) =
+    add("debugImplementation", dependencyNotation)
+
+internal fun DependencyHandler.testImplementation(dependencyNotation: Any) =
+    add("testImplementation", dependencyNotation)
+
+internal fun DependencyHandler.androidTestImplementation(dependencyNotation: Any) =
+    add("androidTestImplementation", dependencyNotation)
+
+internal fun DependencyHandler.ksp(dependencyNotation: Any) =
+    add("ksp", dependencyNotation)
+
+internal fun Project.setupAndroidApp() {
+    applyPlugin(libs.plugins.android.application)
     extensions.configure<ApplicationExtension> {
         namespace = libs.versions.packageName.get()
         compileSdk = libs.versions.compileSdk.get().toInt()
@@ -55,9 +62,6 @@ internal fun Project.setupAndroidApplication() {
             versionCode = libs.versions.appVersionCode.get().toInt()
             versionName = libs.versions.appVersionName.get()
         }
-        buildFeatures {
-            compose = true
-        }
         buildTypes {
             debug {
                 applicationIdSuffix = ".debug"
@@ -70,49 +74,38 @@ internal fun Project.setupAndroidApplication() {
         }
         androidResources {
             generateLocaleConfig = true
-            localeFilters.addAll(listOf("en", "es", "ru", "si", "uk", "zh"))
+            localeFilters.addAll(listOf("en", "es", "ru", "si", "tr", "uk", "zh"))
         }
         packaging { resources { excludes += listOf("META-INF/*") } }
     }
 }
 
-internal fun Project.setupCommonLibrary() {
-    with(pluginManager) {
-        alias(libs.plugins.android.library)
-    }
+internal fun Project.setupAndroidLib() {
+    applyPlugin(libs.plugins.android.library)
     extensions.configure<CommonExtension> {
         compileSdk = libs.versions.compileSdk.get().toInt()
         defaultConfig.minSdk = libs.versions.minSdk.get().toInt()
     }
+    dependencies {
+        androidTestImplementation(libs.bundles.androidTest)
+    }
 }
 
-internal fun Project.setupComposeFeature() {
-    with(pluginManager) {
-        alias(libs.plugins.compose.compiler)
-    }
+internal fun Project.setupCompose() {
+    applyPlugin(libs.plugins.compose.compiler)
     extensions.configure<CommonExtension> {
         buildFeatures.compose = true
     }
     dependencies {
-        IMPLEMENTATION(platform(libs.compose.bom))
-        IMPLEMENTATION(libs.bundles.composeAll)
-        DEBUG_IMPLEMENTATION(libs.bundles.composeDebug)
+        implementation(platform(libs.compose.bom))
+        implementation(libs.bundles.composeAll)
+        debugImplementation(libs.bundles.composeDebug)
     }
 }
 
-internal fun Project.setupKotlinToolchain() {
+internal fun Project.setupKotlin() {
     kotlinExtension.jvmToolchain(libs.versions.jdkVersion.get().toInt())
-}
-
-internal fun Project.setupAndroidTestDependencies() {
     dependencies {
-        ANDROID_TEST_IMPLEMENTATION(libs.bundles.androidTest)
-    }
-}
-
-internal fun Project.setupTestDependencies() {
-    dependencies {
-        TEST_IMPLEMENTATION(libs.test.coroutines)
-        TEST_IMPLEMENTATION(libs.test.junit4)
+        testImplementation(libs.bundles.unitTest)
     }
 }

build.gradle.kts

@@ -4,8 +4,10 @@ plugins {
     alias(libs.plugins.compose.compiler) apply false
     alias(libs.plugins.google.ksp) apply false
     alias(libs.plugins.kotlin.jvm) apply false
+    alias(libs.plugins.kotlin.serialization) apply false
 }
 
 tasks.register("clean", Delete::class.java) {
+    description = "Cleans the build directory"
     delete(rootProject.layout.buildDirectory)
 }

core/data/build.gradle.kts

@@ -1,5 +1,5 @@
 plugins {
-    alias(libs.plugins.convention.androidLibraryPlugin)
+    alias(libs.plugins.convention.coreDataPlugin)
 }
 
 android {

core/data/src/main/AndroidManifest.xml

@@ -2,6 +2,7 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
 
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.ACCESS_LOCAL_NETWORK" />
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
     <uses-permission
@@ -11,5 +12,6 @@
     <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
     <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
     <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.RECORD_AUDIO" />
 
 </manifest>

core/data/src/main/java/com/rtbishop/look4sat/core/data/database/entity/SatRadio.kt

@@ -25,11 +25,11 @@ data class SatRadio(
     @PrimaryKey val uuid: String,
     val info: String,
     val isAlive: Boolean,
-    var downlinkLow: Long?,
-    var downlinkHigh: Long?,
+    val downlinkLow: Long?,
+    val downlinkHigh: Long?,
     val downlinkMode: String?,
-    var uplinkLow: Long?,
-    var uplinkHigh: Long?,
+    val uplinkLow: Long?,
+    val uplinkHigh: Long?,
     val uplinkMode: String?,
     val isInverted: Boolean,
     val catnum: Int?

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/BluetoothReporter.kt

@@ -20,121 +20,112 @@ package com.rtbishop.look4sat.core.data.framework
 import android.bluetooth.BluetoothManager
 import android.bluetooth.BluetoothSocket
 import android.util.Log
-import com.rtbishop.look4sat.core.domain.repository.BtService
-import com.rtbishop.look4sat.core.domain.repository.IReporterRepo
-import com.rtbishop.look4sat.core.domain.repository.WithoutExtParams
+import com.rtbishop.look4sat.core.domain.repository.IReporter
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Job
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import java.io.OutputStream
 import java.util.UUID
-import kotlin.math.abs
-
-data class DeviceConnection(
-    var socket: BluetoothSocket? = null,
-    var outputStream: OutputStream? = null,
-    var connected: Boolean = false,
-    var connecting: Boolean = false,
-    var connectionJob: Job? = null
-)
 
 class BluetoothReporter(
     private val bluetoothManager: BluetoothManager,
-    private val reporterScope: CoroutineScope
-) : IReporterRepo<WithoutExtParams> {
+    private val reporterScope: CoroutineScope,
+    private val rotatorDeviceId: String,
+    private val frequencyDeviceId: String
+) : IReporter {
 
     private val tag = "BTReporter"
-    private val sppid: UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb")
-
-    private val serviceToDevice = mutableMapOf<BtService, String>()
-    private val deviceConnections = mutableMapOf<String, DeviceConnection>()
+    private val sppId: UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb")
     private val writeMutex = Mutex()
 
-    override fun isConnected(service: BtService): Boolean {
-        val deviceId = serviceToDevice[service] ?: return false
-        return deviceConnections[deviceId]?.connected == true
-    }
+    private var rotatorSocket: BluetoothSocket? = null
+    private var rotatorStream: OutputStream? = null
+    private var rotatorConnected = false
+    private var rotatorConnecting = false
 
-    override fun isConnecting(service: BtService): Boolean {
-        val deviceId = serviceToDevice[service] ?: return false
-        return deviceConnections[deviceId]?.connecting == true
-    }
+    private var frequencySocket: BluetoothSocket? = null
+    private var frequencyStream: OutputStream? = null
+    private var frequencyConnected = false
+    private var frequencyConnecting = false
 
-    override fun connect(service: BtService, deviceId: String) {
-        serviceToDevice[service] = deviceId
-        val connection = deviceConnections.getOrPut(deviceId) {
-            DeviceConnection()
+    override fun reportRotation(format: String, azimuth: Double, elevation: Double) {
+        reporterScope.launch {
+            ensureRotatorConnected()
+            if (!rotatorConnected) return@launch
+            val el = if (elevation > 0.0) elevation else 0.0
+            val command = format
+                .replace($$"$AZ", azimuth.toString())
+                .replace($$"$EL", el.toString())
+                .unescapeControlChars()
+            write(rotatorStream, command) { rotatorConnected = false }
         }
-        if (connection.connected || connection.connecting) return
-        connection.connectionJob = reporterScope.launch {
+    }
+
+    override fun reportFrequency(format: String, frequency: Long) {
+        reporterScope.launch {
+            ensureFrequencyConnected()
+            if (!frequencyConnected) return@launch
+            val command = format
+                .replace($$"$FREQ", frequency.toString())
+                .unescapeControlChars()
+            write(frequencyStream, command) { frequencyConnected = false }
+        }
+    }
+
+    private fun ensureRotatorConnected() {
+        if (rotatorConnected || rotatorConnecting || rotatorDeviceId.isBlank()) return
+        reporterScope.launch {
             try {
-                connection.connecting = true
-                val device = bluetoothManager.adapter.getRemoteDevice(deviceId)
-                val socket = device.createInsecureRfcommSocketToServiceRecord(sppid)
+                rotatorConnecting = true
+                val device = bluetoothManager.adapter.getRemoteDevice(rotatorDeviceId)
+                val socket = device.createInsecureRfcommSocketToServiceRecord(sppId)
                 socket.connect()
-                connection.socket = socket
-                connection.outputStream = socket.outputStream
-                connection.connected = true
-                Log.i(tag, "$tag: Connected to $deviceId")
+                rotatorSocket = socket
+                rotatorStream = socket.outputStream
+                rotatorConnected = true
+                Log.i(tag, "Rotator connected to $rotatorDeviceId")
             } catch (e: Exception) {
-                Log.e(tag, "$tag: ${e.message}")
-                connection.connected = false
+                Log.e(tag, "Rotator connect error: ${e.message}")
+                rotatorConnected = false
             } finally {
-                connection.connecting = false
+                rotatorConnecting = false
             }
         }
     }
 
-    private suspend fun write(service: BtService, buffer: String) {
-        val deviceId = serviceToDevice[service] ?: return
-        val connection = deviceConnections[deviceId] ?: return
-        if (!connection.connected) return
+    private fun ensureFrequencyConnected() {
+        if (frequencyConnected || frequencyConnecting || frequencyDeviceId.isBlank()) return
+        reporterScope.launch {
+            try {
+                frequencyConnecting = true
+                val device = bluetoothManager.adapter.getRemoteDevice(frequencyDeviceId)
+                val socket = device.createInsecureRfcommSocketToServiceRecord(sppId)
+                socket.connect()
+                frequencySocket = socket
+                frequencyStream = socket.outputStream
+                frequencyConnected = true
+                Log.i(tag, "Frequency connected to $frequencyDeviceId")
+            } catch (e: Exception) {
+                Log.e(tag, "Frequency connect error: ${e.message}")
+                frequencyConnected = false
+            } finally {
+                frequencyConnecting = false
+            }
+        }
+    }
+
+    private suspend fun write(stream: OutputStream?, data: String, onError: () -> Unit) {
         try {
             writeMutex.withLock {
-                connection.outputStream?.write(buffer.toByteArray())
+                stream?.write(data.toByteArray())
             }
         } catch (e: Exception) {
-            Log.e(tag, "$tag: Write failed ${e.message}")
-            connection.connected = false
+            Log.e(tag, "Write error: ${e.message}")
+            onError()
         }
     }
 
-    override fun reportRotation(format: String, azimuth: Double, elevation: Double, params: WithoutExtParams) {
-        reporterScope.launch {
-            if (!isConnected(BtService.ROTATOR)) return@launch
-            val newElevation = if (elevation > 0.0) elevation else 0.0
-            val azimuthString = intToStringWithLeadingZeroes(azimuth.toInt())
-            val elevationString = intToStringWithLeadingZeroes(newElevation.toInt())
-            val buffer = format
-                .replace($$"$AZ", azimuthString)
-                .replace($$"$EL", elevationString)
-                .replace("\\r", "\r")
-                .replace("\\n", "\n")
-                .replace("\\t", "\t")
-            write(BtService.ROTATOR, buffer)
-        }
-    }
-
-    override fun reportFrequency(format: String, frequency: Long, params: WithoutExtParams) {
-        reporterScope.launch {
-            if (!isConnected(BtService.FREQUENCY)) return@launch
-            val buffer = format
-                .replace($$"$FREQ", frequency.toString())
-                .replace("\\r", "\r")
-                .replace("\\n", "\n")
-                .replace("\\t", "\t")
-            write(BtService.FREQUENCY, buffer)
-        }
-    }
-
-    private fun intToStringWithLeadingZeroes(value: Int): String {
-        return if (value > 0) {
-            if (value < 10) "00$value" else if (value < 100) "0$value" else "$value"
-        } else {
-            val absValue = abs(value)
-            if (value > -10) "-00$absValue" else if (value > -100) "-0$absValue" else "-$absValue"
-        }
-    }
+    private fun String.unescapeControlChars(): String =
+        replace("\\r", "\r").replace("\\n", "\n").replace("\\t", "\t")
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/Ft817CatProtocol.kt

@@ -0,0 +1,139 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.framework
+
+import java.util.Locale
+import kotlin.math.roundToLong
+
+object Ft817CatProtocol {
+
+    const val CMD_SET_FREQ: Byte = 0x01
+    const val CMD_READ_FREQ_MODE: Byte = 0x03
+    const val CMD_SET_MODE: Byte = 0x07
+    const val CMD_PTT_ON: Byte = 0x08
+    const val CMD_PTT_OFF: Byte = 0x88.toByte()
+    const val CMD_CTCSS_MODE: Byte = 0x0A
+    const val CMD_CTCSS_TONE: Byte = 0x0B
+
+    const val CTCSS_ENC_ON: Byte = 0x2A
+    const val CTCSS_OFF: Byte = 0x8A.toByte()
+
+    val MODE_TO_BYTE: Map<String, Byte> = mapOf(
+        "LSB" to 0x00,
+        "USB" to 0x01,
+        "CW" to 0x02,
+        "CW-R" to 0x03,
+        "AM" to 0x04,
+        "FM" to 0x08,
+        "DIG" to 0x0A,
+        "PKT" to 0x0C
+    )
+
+    val BYTE_TO_MODE: Map<Byte, String> = MODE_TO_BYTE.entries.associate { it.value to it.key }
+
+    /**
+     * Encode frequency in Hz to 4-byte BCD with 10 Hz resolution.
+     * Example: 145500000 Hz → [0x14, 0x55, 0x00, 0x00]
+     */
+    fun encodeFrequencyBcd(frequencyHz: Long): ByteArray {
+        val freq10Hz = frequencyHz / 10
+        val bcd = ByteArray(4)
+        val digits = String.format(Locale.US, "%08d", freq10Hz)
+        for (i in 0 until 4) {
+            val high = digits[i * 2] - '0'
+            val low = digits[i * 2 + 1] - '0'
+            bcd[i] = ((high shl 4) or low).toByte()
+        }
+        return bcd
+    }
+
+    /**
+     * Decode 4-byte BCD frequency to Hz.
+     */
+    fun decodeFrequencyBcd(bcd: ByteArray): Long {
+        var freq10Hz = 0L
+        for (i in 0 until 4) {
+            val b = bcd[i].toInt() and 0xFF
+            val high = b shr 4
+            val low = b and 0x0F
+            freq10Hz = freq10Hz * 100 + high * 10 + low
+        }
+        return freq10Hz * 10
+    }
+
+    /**
+     * Encode CTCSS tone frequency (in Hz, e.g. 67.0) to 2-byte BCD.
+     * 67.0 Hz → 670 (in 0.1 Hz) → BCD [0x06, 0x70]
+     */
+    fun encodeCtcssToneBcd(toneHz: Double): ByteArray {
+        val tone01Hz = (toneHz * 10).roundToLong()
+        val digits = String.format(Locale.US, "%04d", tone01Hz)
+        val bcd = ByteArray(2)
+        for (i in 0 until 2) {
+            val high = digits[i * 2] - '0'
+            val low = digits[i * 2 + 1] - '0'
+            bcd[i] = ((high shl 4) or low).toByte()
+        }
+        return bcd
+    }
+
+    fun buildSetFreqCommand(frequencyHz: Long): ByteArray {
+        val bcd = encodeFrequencyBcd(frequencyHz)
+        return byteArrayOf(bcd[0], bcd[1], bcd[2], bcd[3], CMD_SET_FREQ)
+    }
+
+    fun buildSetModeCommand(mode: String): ByteArray? {
+        val modeByte = MODE_TO_BYTE[mode.uppercase(Locale.US)] ?: return null
+        return byteArrayOf(modeByte, 0x00, 0x00, 0x00, CMD_SET_MODE)
+    }
+
+    fun buildReadFreqModeCommand(): ByteArray {
+        return byteArrayOf(0x00, 0x00, 0x00, 0x00, CMD_READ_FREQ_MODE)
+    }
+
+    fun buildPttOnCommand(): ByteArray {
+        return byteArrayOf(0x00, 0x00, 0x00, 0x00, CMD_PTT_ON)
+    }
+
+    fun buildPttOffCommand(): ByteArray {
+        return byteArrayOf(0x00, 0x00, 0x00, 0x00, CMD_PTT_OFF)
+    }
+
+    fun buildCtcssModeCommand(enabled: Boolean): ByteArray {
+        val sub = if (enabled) CTCSS_ENC_ON else CTCSS_OFF
+        return byteArrayOf(sub, 0x00, 0x00, 0x00, CMD_CTCSS_MODE)
+    }
+
+    fun buildSetCtcssToneCommand(toneHz: Double): ByteArray {
+        val bcd = encodeCtcssToneBcd(toneHz)
+        return byteArrayOf(bcd[0], bcd[1], 0x00, 0x00, CMD_CTCSS_TONE)
+    }
+
+    /**
+     * Parse the 5-byte response from a READ FREQ+MODE command.
+     * Returns (frequencyHz, modeString) or null if parsing fails.
+     */
+    fun parseReadResponse(response: ByteArray): Pair<Long, String>? {
+        if (response.size < 5) return null
+        val freqBcd = response.copyOfRange(0, 4)
+        val frequencyHz = decodeFrequencyBcd(freqBcd)
+        val modeByte = response[4]
+        val mode = BYTE_TO_MODE[modeByte] ?: return null
+        return Pair(frequencyHz, mode)
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/Ft817Controller.kt

@@ -0,0 +1,207 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.framework
+
+import android.bluetooth.BluetoothManager
+import android.bluetooth.BluetoothSocket
+import android.util.Log
+import com.rtbishop.look4sat.core.domain.repository.IRadioController
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import kotlinx.coroutines.withContext
+import java.io.InputStream
+import java.io.OutputStream
+import java.util.UUID
+import kotlin.time.Duration.Companion.milliseconds
+
+class Ft817Controller(
+    private val bluetoothManager: BluetoothManager,
+    private val deviceAddress: String
+) : IRadioController {
+
+    private val tag = "FT817"
+    private val sppId: UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb")
+    private val ioMutex = Mutex()
+    private val commandDelayMs = 200L
+    private val maxAckReadFailures = 3
+
+    private var socket: BluetoothSocket? = null
+    private var outputStream: OutputStream? = null
+    private var inputStream: InputStream? = null
+    private var ackReadFailureCount = 0
+
+    override var isConnected: Boolean = false
+        private set
+
+    override suspend fun connect(): Boolean = withContext(Dispatchers.IO) {
+        if (isConnected) return@withContext true
+        if (deviceAddress.isBlank()) return@withContext false
+        try {
+            val device = bluetoothManager.adapter.getRemoteDevice(deviceAddress)
+            val btSocket = device.createInsecureRfcommSocketToServiceRecord(sppId)
+            btSocket.connect()
+            socket = btSocket
+            outputStream = btSocket.outputStream
+            inputStream = btSocket.inputStream
+            ackReadFailureCount = 0
+            isConnected = true
+            Log.i(tag, "Connected to $deviceAddress")
+            true
+        } catch (e: Exception) {
+            Log.e(tag, "Connect error: ${e.message}")
+            isConnected = false
+            false
+        }
+    }
+
+    override suspend fun disconnect() {
+        withContext(Dispatchers.IO) {
+            try {
+                inputStream?.close()
+                outputStream?.close()
+                socket?.close()
+            } catch (e: Exception) {
+                Log.e(tag, "Disconnect error: ${e.message}")
+            } finally {
+                inputStream = null
+                outputStream = null
+                socket = null
+                ackReadFailureCount = 0
+                isConnected = false
+                Log.i(tag, "Disconnected from $deviceAddress")
+            }
+        }
+    }
+
+    override suspend fun setFrequency(frequencyHz: Long): Boolean = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            sendCommandWithAck(Ft817CatProtocol.buildSetFreqCommand(frequencyHz))
+        }
+    }
+
+    override suspend fun setMode(mode: String): Boolean = withContext(Dispatchers.IO) {
+        val cmd = Ft817CatProtocol.buildSetModeCommand(mode) ?: return@withContext false
+        ioMutex.withLock { sendCommandWithAck(cmd) }
+    }
+
+    override suspend fun setCtcssMode(enabled: Boolean): Boolean = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            sendCommandWithAck(Ft817CatProtocol.buildCtcssModeCommand(enabled))
+        }
+    }
+
+    override suspend fun setCtcssTone(toneHz: Double): Boolean = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            sendCommandWithAck(Ft817CatProtocol.buildSetCtcssToneCommand(toneHz))
+        }
+    }
+
+    override suspend fun readFrequencyAndMode(): Pair<Long, String>? = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            val sent = sendCommand(Ft817CatProtocol.buildReadFreqModeCommand())
+            if (!sent) return@withContext null
+            delay(commandDelayMs.milliseconds)
+            val response = readResponse() ?: return@withContext null
+            Ft817CatProtocol.parseReadResponse(response)
+        }
+    }
+
+    override suspend fun pttOn(): Boolean = withContext(Dispatchers.IO) {
+        ioMutex.withLock { sendCommandWithAck(Ft817CatProtocol.buildPttOnCommand()) }
+    }
+
+    override suspend fun pttOff(): Boolean = withContext(Dispatchers.IO) {
+        ioMutex.withLock { sendCommandWithAck(Ft817CatProtocol.buildPttOffCommand()) }
+    }
+
+    private suspend fun sendCommand(bytes: ByteArray): Boolean {
+        return withContext(Dispatchers.IO) {
+            try {
+                outputStream?.write(bytes) ?: return@withContext false
+                outputStream?.flush()
+                delay(commandDelayMs.milliseconds)
+                true
+            } catch (e: Exception) {
+                Log.e(tag, "Send error: ${e.message}")
+                isConnected = false
+                false
+            }
+        }
+    }
+
+    /** Send command and read the 1-byte ACK response (0x00 = OK). */
+    private suspend fun sendCommandWithAck(bytes: ByteArray): Boolean {
+        if (!sendCommand(bytes)) return false
+        return withContext(Dispatchers.IO) {
+            try {
+                val ack = inputStream?.read() ?: run {
+                    ackReadFailureCount = 0
+                    isConnected = false
+                    return@withContext false
+                }
+                if (ack < 0) {
+                    ackReadFailureCount = 0
+                    Log.i(tag, "ACK stream closed by remote device")
+                    isConnected = false
+                    return@withContext false
+                }
+                ackReadFailureCount = 0
+                ack == 0x00
+            } catch (e: Exception) {
+                ackReadFailureCount += 1
+                Log.w(tag, "ACK read error (${ackReadFailureCount}/$maxAckReadFailures): ${e.message}")
+                if (ackReadFailureCount >= maxAckReadFailures) {
+                    Log.e(tag, "Too many ACK read errors, marking radio disconnected")
+                    isConnected = false
+                    false
+                } else {
+                    true // Command was sent, treat transient ACK read failures as best-effort
+                }
+            }
+        }
+    }
+
+    private suspend fun readResponse(): ByteArray? {
+        return withContext(Dispatchers.IO) {
+            try {
+                val responseSize = 5
+                val buffer = ByteArray(responseSize)
+                var read = 0
+                while (read < responseSize) {
+                    val count = inputStream?.read(buffer, read, responseSize - read) ?: run {
+                        isConnected = false
+                        return@withContext null
+                    }
+                    if (count < 0) {
+                        Log.i(tag, "Response stream closed by remote device")
+                        isConnected = false
+                        return@withContext null
+                    }
+                    read += count
+                }
+                buffer
+            } catch (e: Exception) {
+                Log.e(tag, "Read error: ${e.message}")
+                isConnected = false
+                null
+            }
+        }
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/Ic705Controller.kt

@@ -0,0 +1,364 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.framework
+
+import android.bluetooth.BluetoothManager
+import android.bluetooth.BluetoothSocket
+import android.util.Log
+import com.rtbishop.look4sat.core.domain.repository.IRadioController
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import kotlinx.coroutines.withContext
+import java.io.InputStream
+import java.io.OutputStream
+import java.util.UUID
+
+/**
+ * Icom IC-705 CI-V controller over Bluetooth SPP.
+ *
+ * The IC-705 emits broadcast frames continuously (band scope, UTC, signal
+ * level, …).  A reply to any command we send may therefore be buried in
+ * that noise.  All response reads drain up to [ACK_TIMEOUT_MS] and scan the
+ * entire accumulated buffer for the frame we expect rather than assuming
+ * the very next byte is the response.
+ */
+class Ic705Controller(
+    private val bluetoothManager: BluetoothManager,
+    private val deviceAddress: String
+) : IRadioController {
+
+    private val tag = "IC705"
+    private val sppId: UUID = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb")
+    private val ioMutex = Mutex()
+
+    /** Time budget (ms) to wait for a response amid broadcast noise. */
+    private val ACK_TIMEOUT_MS = 500L
+    /** Polling interval while draining the input buffer. */
+    private val POLL_INTERVAL_MS = 20L
+    /** Small pause after writing a command before reading the response. */
+    private val WRITE_SETTLE_MS = 50L
+
+    private var socket: BluetoothSocket? = null
+    private var outputStream: OutputStream? = null
+    private var inputStream: InputStream? = null
+
+    override var isConnected: Boolean = false
+        private set
+
+    // ── Connection ──────────────────────────────────────────────────────────
+
+    override suspend fun connect(): Boolean = withContext(Dispatchers.IO) {
+        if (isConnected) return@withContext true
+        if (deviceAddress.isBlank()) return@withContext false
+        try {
+            val device  = bluetoothManager.adapter.getRemoteDevice(deviceAddress)
+            val btSocket = device.createInsecureRfcommSocketToServiceRecord(sppId)
+            btSocket.connect()
+            socket       = btSocket
+            outputStream = btSocket.outputStream
+            inputStream  = btSocket.inputStream
+            isConnected  = true
+            // Enter VFO mode — frequency/mode commands return FA if the radio
+            // is in memory-channel mode. Safe to send regardless of current state.
+            Log.i(tag, "Connected to $deviceAddress — entering VFO mode")
+            val vfoCmd = IcomCivProtocol.buildEnterVfoModeCommand()
+            Log.d(tag, "CMD enterVfoMode → ${IcomCivProtocol.toHex(vfoCmd)}")
+            ioMutex.withLock { sendAndWaitAck(vfoCmd) }
+            true
+        } catch (e: Exception) {
+            Log.e(tag, "Connect error: ${e.message}")
+            isConnected = false
+            false
+        }
+    }
+
+    override suspend fun disconnect() {
+        withContext(Dispatchers.IO) {
+            try {
+                inputStream?.close()
+                outputStream?.close()
+                socket?.close()
+            } catch (e: Exception) {
+                Log.e(tag, "Disconnect error: ${e.message}")
+            } finally {
+                inputStream  = null
+                outputStream = null
+                socket       = null
+                isConnected  = false
+                Log.i(tag, "Disconnected from $deviceAddress")
+            }
+        }
+    }
+
+    // ── IRadioController – standard operations ──────────────────────────────
+
+    override suspend fun setFrequency(frequencyHz: Long): Boolean = withContext(Dispatchers.IO) {
+        Log.d(tag, "setFrequency: ${frequencyHz}Hz")
+        ioMutex.withLock {
+            val cmd = IcomCivProtocol.buildSetFreqCommand(frequencyHz)
+            Log.d(tag, "CMD setFreq → ${IcomCivProtocol.toHex(cmd)}")
+            sendAndWaitAck(cmd)
+        }
+    }
+
+    override suspend fun setMode(mode: String): Boolean = withContext(Dispatchers.IO) {
+        val cmd = IcomCivProtocol.buildSetModeCommand(mode) ?: run {
+            Log.w(tag, "setMode: unknown mode '$mode'")
+            return@withContext false
+        }
+        Log.d(tag, "setMode: $mode")
+        Log.d(tag, "CMD setMode → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    override suspend fun setCtcssMode(enabled: Boolean): Boolean = withContext(Dispatchers.IO) {
+        Log.d(tag, "setCtcssMode: $enabled")
+        val cmd = IcomCivProtocol.buildCtcssModeCommand(enabled)
+        Log.d(tag, "CMD ctcssMode → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    override suspend fun setCtcssTone(toneHz: Double): Boolean = withContext(Dispatchers.IO) {
+        Log.d(tag, "setCtcssTone: ${toneHz}Hz")
+        val cmd = IcomCivProtocol.buildSetCtcssToneCommand(toneHz)
+        Log.d(tag, "CMD ctcssTone → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    override suspend fun readFrequencyAndMode(): Pair<Long, String>? = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            val cmd = IcomCivProtocol.buildReadFreqCommand()
+            Log.d(tag, "CMD readFreq → ${IcomCivProtocol.toHex(cmd)}")
+            val payload = sendAndReadResponse(cmd, IcomCivProtocol.CMD_READ_FREQ) ?: return@withContext null
+            // Read-freq reply payload: [cmd byte already stripped by parseResponse] [5 freq bytes] [mode] [filter]
+            IcomCivProtocol.parseFreqModePayload(payload).also {
+                if (it != null) Log.d(tag, "readFreqMode: ${it.first}Hz, ${it.second}")
+                else Log.w(tag, "readFreqMode: parse failed, payload=${IcomCivProtocol.toHex(payload)}")
+            }
+        }
+    }
+
+    override suspend fun pttOn(): Boolean = withContext(Dispatchers.IO) {
+        Log.w(tag, "pttOn: not used for IC-705")
+        true
+    }
+
+    override suspend fun pttOff(): Boolean = withContext(Dispatchers.IO) {
+        Log.w(tag, "pttOff: not used for IC-705")
+        true
+    }
+
+    // ── IRadioController – IC-705 extended operations ───────────────────────
+
+    /** Select the band for [frequencyHz] via CMD 0x1A sub 0x00 (band stacking register). */
+    override suspend fun setBand(frequencyHz: Long): Boolean = withContext(Dispatchers.IO) {
+        val cmd = IcomCivProtocol.buildBandSelectCommand(frequencyHz) ?: run {
+            Log.w(tag, "setBand: no band code for ${frequencyHz}Hz — skipping")
+            return@withContext false
+        }
+        Log.d(tag, "CMD setBand (${frequencyHz}Hz) → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    /** Select VFO-A (main/RX) or VFO-B (sub/TX). */
+    override suspend fun setVfo(vfoA: Boolean): Boolean = withContext(Dispatchers.IO) {
+        val cmd = if (vfoA) IcomCivProtocol.buildSelectVfoACommand()
+                  else      IcomCivProtocol.buildSelectVfoBCommand()
+        Log.d(tag, "CMD selectVFO${if (vfoA) "A" else "B"} → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    /**
+     * Enable or disable SPLIT mode (TX on sub-VFO while listening on main VFO).
+     */
+    override suspend fun setSplitMode(enabled: Boolean): Boolean = withContext(Dispatchers.IO) {
+        val cmd = IcomCivProtocol.buildSplitModeCommand(enabled)
+        Log.d(tag, "CMD split ${if (enabled) "ON" else "OFF"} → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    /**
+     * Set the frequency of the **currently active** VFO (CMD 0x25 sub 0x00).
+     * In split mode the radio automatically switches active VFO on PTT, so
+     * always writing to the active VFO is the correct strategy.
+     */
+    override suspend fun setWorkingFrequency(frequencyHz: Long): Boolean = withContext(Dispatchers.IO) {
+        Log.d(tag, "setWorkingFrequency (0x25/00): ${frequencyHz}Hz")
+        val cmd = IcomCivProtocol.buildSetWorkingFreqCommand(frequencyHz)
+        Log.d(tag, "CMD setWorkingFreq → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    /**
+     * Set TX VFO frequency via CMD 0x25 sub 0x01 (unselected VFO).
+     * Sent every tracking cycle in split mode alongside [setWorkingFrequency].
+     */
+    override suspend fun setTxVfoFrequency(frequencyHz: Long): Boolean = withContext(Dispatchers.IO) {
+        Log.d(tag, "setTxVfoFrequency (0x25/01): ${frequencyHz}Hz")
+        val cmd = IcomCivProtocol.buildSetUnselectedVfoFreqCommand(frequencyHz)
+        Log.d(tag, "CMD setTxVfoFreq → ${IcomCivProtocol.toHex(cmd)}")
+        ioMutex.withLock { sendAndWaitAck(cmd) }
+    }
+
+    /**
+     * Read the frequency of the currently active VFO (CMD 0x25 sub 0x00).
+     * Used for tuning detection in split mode.
+     */
+    override suspend fun readWorkingFrequency(): Long? = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            val cmd = IcomCivProtocol.buildReadWorkingFreqCommand()
+            Log.d(tag, "CMD readWorkingFreq → ${IcomCivProtocol.toHex(cmd)}")
+            val payload = sendAndReadResponse(cmd, IcomCivProtocol.CMD_SELECTED_VFO_FREQ) ?: return@withContext null
+            // Response payload: [sub] [5 freq bytes] — CMD byte already stripped by parseResponse
+            Log.d(tag, "readWorkingFreq: got ${payload.size} bytes: ${IcomCivProtocol.toHex(payload)}")
+            if (payload.size < 6) {
+                Log.w(tag, "readWorkingFreq: payload too short (${payload.size} bytes)")
+                return@withContext null
+            }
+            val freqBcd = payload.sliceArray(1..5)
+            val freq = IcomCivProtocol.decodeFrequencyBcd(freqBcd)
+            Log.d(tag, "readWorkingFreq: ${freq}Hz")
+            freq
+        }
+    }
+
+    /**
+     * Read the frequency of the inactive/TX VFO (CMD 0x25 sub 0x01).
+     * Used for tuning detection in split mode.
+     */
+    override suspend fun readTxVfoFrequency(): Long? = withContext(Dispatchers.IO) {
+        ioMutex.withLock {
+            val cmd = IcomCivProtocol.buildReadTxVfoFreqCommand()
+            Log.d(tag, "CMD readTxVfoFreq → ${IcomCivProtocol.toHex(cmd)}")
+            val payload = sendAndReadResponse(cmd, IcomCivProtocol.CMD_SELECTED_VFO_FREQ) ?: return@withContext null
+            // Response payload: [sub] [5 freq bytes] — CMD byte already stripped by parseResponse
+            Log.d(tag, "readTxVfoFreq: got ${payload.size} bytes: ${IcomCivProtocol.toHex(payload)}")
+            if (payload.size < 6) {
+                Log.w(tag, "readTxVfoFreq: payload too short (${payload.size} bytes)")
+                return@withContext null
+            }
+            val freqBcd = payload.sliceArray(1..5)
+            val freq = IcomCivProtocol.decodeFrequencyBcd(freqBcd)
+            Log.d(tag, "readTxVfoFreq: ${freq}Hz")
+            freq
+        }
+    }
+
+    // ── Internal I/O helpers ────────────────────────────────────────────────
+
+    /**
+     * Write [cmd] to the radio and drain the input stream for up to
+     * [ACK_TIMEOUT_MS], looking for an OK/NG acknowledgement frame.
+     */
+    private suspend fun sendAndWaitAck(cmd: ByteArray): Boolean {
+        if (!write(cmd)) return false
+        delay(WRITE_SETTLE_MS)
+        val buf = drainWithTimeout(ACK_TIMEOUT_MS)
+        val ok  = IcomCivProtocol.containsAck(buf)
+        if (!ok) Log.w(tag, "ACK not found in ${buf.size} bytes: ${IcomCivProtocol.toHex(buf)}")
+        return ok
+    }
+
+    /**
+     * Write [cmd] to the radio and drain the input stream for up to
+     * [ACK_TIMEOUT_MS], scanning for a response frame carrying [expectCmd].
+     * Returns the payload bytes of that frame, or null on timeout/error.
+     */
+    private suspend fun sendAndReadResponse(cmd: ByteArray, expectCmd: Byte): ByteArray? {
+        if (!write(cmd)) return null
+        delay(WRITE_SETTLE_MS)
+        val buf      = drainWithTimeout(ACK_TIMEOUT_MS)
+        val response = IcomCivProtocol.parseResponse(buf, expectCmd)
+        if (response == null) {
+            Log.w(tag, "No response for cmd 0x${String.format("%02X", expectCmd.toInt() and 0xFF)} " +
+                    "in ${buf.size} bytes: ${IcomCivProtocol.toHex(buf)}")
+        }
+        return response?.payload
+    }
+
+    /**
+     * Drain whatever bytes the radio has buffered within a [timeoutMs] window.
+     * Exits early as soon as a complete CI-V frame addressed to us is present
+     * in the buffer (i.e., FE FE E0 A4 … FD), so we don't waste the remaining
+     * timeout on responses that already arrived.
+     */
+    private suspend fun drainWithTimeout(timeoutMs: Long): ByteArray {
+        val result   = mutableListOf<Byte>()
+        val deadline = System.currentTimeMillis() + timeoutMs
+        val stream   = inputStream ?: return ByteArray(0)
+        while (System.currentTimeMillis() < deadline) {
+            try {
+                val available = stream.available()
+                if (available > 0) {
+                    val chunk = ByteArray(available)
+                    val read  = stream.read(chunk)
+                    if (read > 0) {
+                        result.addAll(chunk.take(read))
+                        // Exit early once we have a complete frame for us
+                        if (hasCompleteFrameForUs(result)) break
+                    }
+                } else {
+                    delay(POLL_INTERVAL_MS)
+                }
+            } catch (e: Exception) {
+                Log.e(tag, "Drain error: ${e.message}")
+                isConnected = false
+                break
+            }
+        }
+        return result.toByteArray()
+    }
+
+    /**
+     * Returns true if [buf] contains a complete CI-V frame addressed to the
+     * controller (FE FE [ADDR_CTRL] [ADDR_IC705] … FD).
+     * CI-V data bytes cannot be 0xFD, so the first 0xFD after the header is
+     * always the frame terminator.
+     */
+    private fun hasCompleteFrameForUs(buf: List<Byte>): Boolean {
+        var i = 0
+        while (i < buf.size - 4) {
+            if (buf[i]     == IcomCivProtocol.PREAMBLE    &&
+                buf[i + 1] == IcomCivProtocol.PREAMBLE    &&
+                buf[i + 2] == IcomCivProtocol.ADDR_CTRL   &&
+                buf[i + 3] == IcomCivProtocol.ADDR_IC705
+            ) {
+                for (k in i + 4 until buf.size) {
+                    if (buf[k] == IcomCivProtocol.END_OF_MSG) return true
+                }
+                return false  // header found but no FD yet
+            }
+            i++
+        }
+        return false
+    }
+
+    private fun write(bytes: ByteArray): Boolean {
+        return try {
+            outputStream?.write(bytes)
+            outputStream?.flush()
+            true
+        } catch (e: Exception) {
+            Log.e(tag, "Write error: ${e.message}")
+            isConnected = false
+            false
+        }
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/IcomCivProtocol.kt

@@ -0,0 +1,352 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.framework
+
+import java.util.Locale
+
+/**
+ * Icom CI-V protocol encoder/decoder for the IC-705.
+ *
+ * Frame structure:
+ *   FE FE <DEST> <SRC> <CMD> [<SUB>] [<DATA...>] FD
+ *
+ * IC-705 default CI-V address : 0xA4
+ * Controller (us) address     : 0xE0
+ */
+object IcomCivProtocol {
+
+    // ── Framing constants ──────────────────────────────────────────────────
+    const val PREAMBLE: Byte      = 0xFE.toByte()
+    const val END_OF_MSG: Byte    = 0xFD.toByte()
+    const val ACK_OK: Byte        = 0xFB.toByte()
+    const val ACK_NG: Byte        = 0xFA.toByte()
+
+    // ── Address constants ──────────────────────────────────────────────────
+    /** Default CI-V address of the IC-705. */
+    const val ADDR_IC705: Byte    = 0xA4.toByte()
+    /** Default CI-V address of the controller (us). */
+    const val ADDR_CTRL: Byte     = 0xE0.toByte()
+
+    // ── Command bytes ──────────────────────────────────────────────────────
+    /** Read operating frequency (main VFO). */
+    const val CMD_READ_FREQ: Byte           = 0x03
+    /** Set operating frequency (main VFO). */
+    const val CMD_SET_FREQ: Byte            = 0x05
+    /** Set operating mode. */
+    const val CMD_SET_MODE: Byte            = 0x06
+    /** Select VFO / memory. */
+    const val CMD_SELECT_VFO: Byte          = 0x07
+    /**
+     * Select operating mode (VFO vs memory-channel).
+     * Sub 0x00 = VFO mode. Must be sent after connect if the radio is in
+     * memory-channel mode — frequency/mode commands return FA until it is.
+     */
+    const val CMD_SELECT_OP_MODE: Byte      = 0x08
+    /** Set repeater duplex / SPLIT. */
+    const val CMD_DUPLEX_SPLIT: Byte        = 0x0F
+    /** Band stacking register / band select (sub 0x00 = select, data = BCD band number). */
+    const val CMD_BAND_SELECT: Byte         = 0x1A
+    /** Read/write CTCSS tone frequency. */
+    const val CMD_CTCSS_TONE: Byte          = 0x1B
+    /** Read/write misc settings (used for enabling CTCSS encode). */
+    const val CMD_MISC_SETTING: Byte        = 0x16
+    /** Read/write selected-VFO frequency (cmd 0x25). */
+    const val CMD_SELECTED_VFO_FREQ: Byte   = 0x25
+
+    // ── Sub-command bytes ──────────────────────────────────────────────────
+    /** Sub for CMD_SELECT_VFO: select VFO-A (main). */
+    const val SUB_VFO_A: Byte   = 0x00
+    /** Sub for CMD_SELECT_VFO: select VFO-B (sub). */
+    const val SUB_VFO_B: Byte   = 0x01
+    /** Sub for CMD_DUPLEX_SPLIT: simplex / split OFF. */
+    const val SUB_SPLIT_OFF: Byte = 0x00
+    /** Sub for CMD_DUPLEX_SPLIT: SPLIT ON. */
+    const val SUB_SPLIT_ON: Byte  = 0x01
+    /** Sub for CMD_SELECTED_VFO_FREQ: selected (active) VFO frequency. */
+    const val SUB_SELECTED_VFO: Byte = 0x00
+    /** Sub for CMD_SELECTED_VFO_FREQ: unselected (inactive / TX in split) VFO frequency. */
+    const val SUB_UNSELECTED_VFO: Byte = 0x01
+    /** Sub for CMD_MISC_SETTING: CTCSS/DTCS tone squelch. */
+    const val SUB_CTCSS_SETTING: Byte = 0x42.toByte()
+
+    // ── Mode bytes ────────────────────────────────────────────────────────
+    /** Maps mode strings (upper-case) → IC-705 mode bytes. */
+    val MODE_TO_BYTE: Map<String, Byte> = mapOf(
+        "LSB"    to 0x00,
+        "USB"    to 0x01,
+        "AM"     to 0x02,
+        "CW"     to 0x03,
+        "RTTY"   to 0x04,
+        "FM"     to 0x05,
+        "WFM"    to 0x06,
+        "CW-R"   to 0x07,
+        "RTTY-R" to 0x08,
+        "DV"     to 0x12,
+        "AFSK"   to 0x05  // AFSK uses FM modulation
+    )
+
+    val BYTE_TO_MODE: Map<Byte, String> = MODE_TO_BYTE.entries.associate { it.value to it.key }
+
+    // ── Frequency BCD encoding ─────────────────────────────────────────────
+
+    /**
+     * Encode a frequency in Hz to the IC-705's 5-byte BCD format.
+     *
+     * The IC-705 uses 5 bytes, LSB pair first, with 1 Hz resolution.
+     * Example: 145,500,000 Hz → "0145500000" → pairs LSB→MSB:
+     *   [00, 00, 50, 45, 01]
+     */
+    fun encodeFrequencyBcd(frequencyHz: Long): ByteArray {
+        val digits = String.format(Locale.US, "%010d", frequencyHz)
+        val bcd = ByteArray(5)
+        for (i in 0 until 5) {
+            // digits are MSB first; we want pair index 0 = LSB pair
+            val pairIndex = 4 - i
+            val high = digits[pairIndex * 2] - '0'
+            val low  = digits[pairIndex * 2 + 1] - '0'
+            bcd[i] = ((high shl 4) or low).toByte()
+        }
+        return bcd
+    }
+
+    /**
+     * Decode 5-byte BCD frequency (LSB pair first) to Hz.
+     */
+    fun decodeFrequencyBcd(bcd: ByteArray): Long {
+        // Build digit string MSB→LSB by reversing the byte order
+        var freqHz = 0L
+        for (i in 4 downTo 0) {
+            val b    = bcd[i].toInt() and 0xFF
+            val high = b shr 4
+            val low  = b and 0x0F
+            freqHz   = freqHz * 100 + high * 10 + low
+        }
+        return freqHz
+    }
+
+    /**
+     * Encode a CTCSS tone (Hz, e.g. 67.0) to 2-byte BCD (0.1 Hz resolution).
+     * 67.0 → 670 (tenths of Hz) → BCD bytes [0x06, 0x70].
+     */
+    fun encodeCtcssToneBcd(toneHz: Double): ByteArray {
+        val tone01 = (toneHz * 10).toLong()
+        val digits = String.format(Locale.US, "%04d", tone01)
+        return byteArrayOf(
+            ((digits[0] - '0') shl 4 or (digits[1] - '0')).toByte(),
+            ((digits[2] - '0') shl 4 or (digits[3] - '0')).toByte()
+        )
+    }
+
+    // ── Message builders ───────────────────────────────────────────────────
+
+    /** Wrap payload bytes in a CI-V frame: FE FE DEST SRC ... FD. */
+    private fun frame(vararg payload: Byte): ByteArray {
+        return byteArrayOf(PREAMBLE, PREAMBLE, ADDR_IC705, ADDR_CTRL) +
+                payload +
+                byteArrayOf(END_OF_MSG)
+    }
+
+    /** Set operating frequency via CMD 0x05 (main VFO). */
+    fun buildSetFreqCommand(frequencyHz: Long): ByteArray {
+        return frame(CMD_SET_FREQ, *encodeFrequencyBcd(frequencyHz))
+    }
+
+    /**
+     * Set selected-VFO frequency via CMD 0x25 sub 0x00.
+     * This updates whichever VFO is currently active (RX or TX after split).
+     */
+    fun buildSetWorkingFreqCommand(frequencyHz: Long): ByteArray {
+        return frame(CMD_SELECTED_VFO_FREQ, SUB_SELECTED_VFO, *encodeFrequencyBcd(frequencyHz))
+    }
+
+    /**
+     * Set unselected-VFO frequency via CMD 0x25 sub 0x01.
+     * In split mode while PTT is pressed the IC-705 makes VFO-B active, so
+     * this command targets VFO-A (the RX VFO) — and vice-versa when in RX.
+     * Use this to update the TX VFO when PTT is on.
+     */
+    fun buildSetUnselectedVfoFreqCommand(frequencyHz: Long): ByteArray {
+        return frame(CMD_SELECTED_VFO_FREQ, SUB_UNSELECTED_VFO, *encodeFrequencyBcd(frequencyHz))
+    }
+
+    /** Read operating frequency (CMD 0x03). */
+    fun buildReadFreqCommand(): ByteArray = frame(CMD_READ_FREQ)
+
+    /** Read selected (active) VFO frequency (CMD 0x25 sub 0x00). */
+    fun buildReadWorkingFreqCommand(): ByteArray = frame(CMD_SELECTED_VFO_FREQ, SUB_SELECTED_VFO)
+
+    /** Read unselected (inactive/TX in split) VFO frequency (CMD 0x25 sub 0x01). */
+    fun buildReadTxVfoFreqCommand(): ByteArray = frame(CMD_SELECTED_VFO_FREQ, SUB_UNSELECTED_VFO)
+
+    /**
+     * Select band via CMD 0x1A sub 0x00.
+     * Band codes are BCD-numbered: 1=160m, 2=80m, …, 9=10m, 0x10=6m, 0x11=2m, 0x12=70cm, 0x13=23cm.
+     * Returns null if [frequencyHz] doesn't fall in a known amateur band.
+     */
+    fun buildBandSelectCommand(frequencyHz: Long): ByteArray? {
+        val code = bandCodeForFrequency(frequencyHz) ?: return null
+        return frame(CMD_BAND_SELECT, 0x00, code)
+    }
+
+    /**
+     * Map a frequency in Hz to the IC-705 band stacking register code.
+     * Codes are BCD (band number in decimal expressed as hex nibbles).
+     */
+    fun bandCodeForFrequency(frequencyHz: Long): Byte? = when {
+        frequencyHz in 1_800_000L     ..1_999_999L     -> 0x01 // 160 m
+        frequencyHz in 3_500_000L     ..3_999_999L     -> 0x02 // 80 m
+        frequencyHz in 7_000_000L     ..7_299_999L     -> 0x03 // 40 m
+        frequencyHz in 10_100_000L    ..10_149_999L    -> 0x04 // 30 m
+        frequencyHz in 14_000_000L    ..14_349_999L    -> 0x05 // 20 m
+        frequencyHz in 18_068_000L    ..18_167_999L    -> 0x06 // 17 m
+        frequencyHz in 21_000_000L    ..21_449_999L    -> 0x07 // 15 m
+        frequencyHz in 24_890_000L    ..24_989_999L    -> 0x08 // 12 m
+        frequencyHz in 28_000_000L    ..29_699_999L    -> 0x09 // 10 m
+        frequencyHz in 50_000_000L    ..53_999_999L    -> 0x10 // 6 m  (BCD 10)
+        frequencyHz in 144_000_000L   ..147_999_999L   -> 0x11 // 2 m  (BCD 11)
+        frequencyHz in 420_000_000L   ..449_999_999L   -> 0x12 // 70 cm (BCD 12)
+        frequencyHz in 1_240_000_000L ..1_299_999_999L -> 0x13 // 23 cm (BCD 13)
+        else -> null
+    }
+
+    /** Set operating mode (CMD 0x06). Filter byte is omitted — radio uses its default filter for the mode. */
+    fun buildSetModeCommand(mode: String): ByteArray? {
+        val modeByte = MODE_TO_BYTE[mode.uppercase(Locale.US)] ?: return null
+        return frame(CMD_SET_MODE, modeByte)
+    }
+
+    /** Select VFO-A (CMD 0x07 sub 0x00). */
+    fun buildSelectVfoACommand(): ByteArray = frame(CMD_SELECT_VFO, SUB_VFO_A)
+
+    /** Select VFO-B (CMD 0x07 sub 0x01). */
+    fun buildSelectVfoBCommand(): ByteArray = frame(CMD_SELECT_VFO, SUB_VFO_B)
+
+    /**
+     * Enter VFO operating mode (CMD 0x08 sub 0x00).
+     * Sent after connect — if the radio is in memory-channel mode frequency
+     * and mode commands return FA until this is issued.
+     */
+    fun buildEnterVfoModeCommand(): ByteArray = frame(CMD_SELECT_OP_MODE, 0x00)
+
+    /** Enable or disable SPLIT mode (CMD 0x0F). */
+    fun buildSplitModeCommand(enable: Boolean): ByteArray {
+        val sub = if (enable) SUB_SPLIT_ON else SUB_SPLIT_OFF
+        return frame(CMD_DUPLEX_SPLIT, sub)
+    }
+
+    /**
+     * Enable/disable CTCSS encode (CMD 0x16 sub 0x42).
+     * 0x01 = CTCSS encoder ON, 0x00 = OFF.
+     */
+    fun buildCtcssModeCommand(enabled: Boolean): ByteArray {
+        val value: Byte = if (enabled) 0x01 else 0x00
+        return frame(CMD_MISC_SETTING, SUB_CTCSS_SETTING, value)
+    }
+
+    /**
+     * Set CTCSS tone frequency (CMD 0x1B sub 0x00).
+     */
+    fun buildSetCtcssToneCommand(toneHz: Double): ByteArray {
+        val bcd = encodeCtcssToneBcd(toneHz)
+        return frame(CMD_CTCSS_TONE, 0x00, *bcd)
+    }
+
+    // ── Response parsing ───────────────────────────────────────────────────
+
+    /**
+     * Find and parse a complete CI-V response frame from a buffer.
+     *
+     * Returns the bytes between "FE FE E0 A4 <CMD>" and FD, or null if no
+     * complete frame was found. The search is tolerant of interleaved
+     * broadcast traffic.
+     *
+     * @param buf       bytes accumulated from the radio
+     * @param expectCmd the command byte we are looking for in the reply, or
+     *                  null to accept any command response from the radio
+     */
+    fun parseResponse(buf: ByteArray, expectCmd: Byte?): ParsedResponse? {
+        var i = 0
+        while (i < buf.size - 5) {
+            // Look for FE FE preamble
+            if (buf[i] != PREAMBLE || buf[i + 1] != PREAMBLE) { i++; continue }
+            val dest = buf[i + 2]
+            val src  = buf[i + 3]
+            val cmd  = buf[i + 4]
+            // We only care about frames addressed to us from the radio
+            if (dest != ADDR_CTRL || src != ADDR_IC705) { i++; continue }
+            // Find the terminating FD
+            val fdIdx = buf.indexOf(END_OF_MSG, startIndex = i + 5)
+            if (fdIdx < 0) break  // incomplete frame, wait for more data
+            val payload = buf.copyOfRange(i + 5, fdIdx)
+            if (expectCmd == null || cmd == expectCmd) {
+                return ParsedResponse(cmd, payload, fdIdx + 1)
+            }
+            i = fdIdx + 1
+        }
+        return null
+    }
+
+    private fun ByteArray.indexOf(b: Byte, startIndex: Int): Int {
+        for (k in startIndex until size) if (this[k] == b) return k
+        return -1
+    }
+
+    /**
+     * Check whether a buffer contains an OK acknowledgement (FB FD) from
+     * the radio. Tolerates broadcast noise before the ACK.
+     */
+    fun containsAck(buf: ByteArray): Boolean {
+        var i = 0
+        while (i < buf.size - 5) {
+            if (buf[i] != PREAMBLE || buf[i + 1] != PREAMBLE) { i++; continue }
+            val dest = buf[i + 2]
+            val src  = buf[i + 3]
+            val cmd  = buf[i + 4]
+            if (dest != ADDR_CTRL || src != ADDR_IC705) { i++; continue }
+            // Skip to FD
+            val fdIdx = buf.indexOf(END_OF_MSG, startIndex = i + 5)
+            if (fdIdx < 0) break
+            if (cmd == ACK_OK) return true
+            if (cmd == ACK_NG) return false
+            i = fdIdx + 1
+        }
+        return false
+    }
+
+    /**
+     * Parse frequency + mode from a CMD_READ_FREQ reply payload.
+     * Payload layout after stripping command byte: [5 freq bytes] [mode byte] [filter byte]
+     */
+    fun parseFreqModePayload(payload: ByteArray): Pair<Long, String>? {
+        if (payload.size < 6) return null
+        val freqHz = decodeFrequencyBcd(payload.copyOfRange(0, 5))
+        val mode   = BYTE_TO_MODE[payload[5]] ?: return null
+        return freqHz to mode
+    }
+
+    /** Hex dump of bytes, useful for debug logging. */
+    fun toHex(bytes: ByteArray): String =
+        bytes.joinToString(" ") { String.format(Locale.US, "%02X", it.toInt() and 0xFF) }
+
+    data class ParsedResponse(
+        val cmd: Byte,
+        val payload: ByteArray,
+        /** Index in the source buffer immediately after the FD terminator. */
+        val nextOffset: Int
+    )
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/NetworkReporter.kt

@@ -17,11 +17,10 @@
  */
 package com.rtbishop.look4sat.core.data.framework
 
-import com.rtbishop.look4sat.core.domain.repository.BtService
-import com.rtbishop.look4sat.core.domain.repository.ExtendedParams
-import com.rtbishop.look4sat.core.domain.repository.IReporterRepo
+import com.rtbishop.look4sat.core.domain.model.Constants
+import com.rtbishop.look4sat.core.domain.repository.IReporter
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Job
+import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
@@ -29,89 +28,133 @@ import java.net.InetSocketAddress
 import java.nio.ByteBuffer
 import java.nio.channels.SocketChannel
 
-enum class NetworkService { ROTATOR, FREQUENCY }
+class NetworkReporter(
+    private val reporterScope: CoroutineScope,
+    private val rotatorServer: String,
+    private val rotatorPort: Int,
+    private val frequencyServer: String,
+    private val frequencyPort: Int,
+    private val frequencyOffsetHz: Long = 0L
+) : IReporter {
 
-data class SocketConnection(
-    var socket: SocketChannel? = null,
-    var connected: Boolean = false,
-    var connecting: Boolean = false,
-    var connectionJob: Job? = null
-)
-
-class NetworkReporter(private val reporterScope: CoroutineScope) : IReporterRepo<ExtendedParams> {
-    private val serviceToAddress = mutableMapOf<NetworkService, String>()
-    private val connections = mutableMapOf<String, SocketConnection>()
     private val writeMutex = Mutex()
+    private val connectionMutex = Mutex()
+    private val frequencyCommands = Channel<String>(Channel.CONFLATED)
 
-    fun isConnected(service: NetworkService): Boolean {
-        val addr = serviceToAddress[service] ?: return false
-        return connections[addr]?.connected == true
-    }
+    private var rotatorSocket: SocketChannel? = null
+    private var rotatorConnected = false
 
-    private fun getOrCreateConnection(addr: String): SocketConnection {
-        return connections.getOrPut(addr) { SocketConnection() }
-    }
+    private var frequencySocket: SocketChannel? = null
+    private var frequencyConnected = false
 
-    fun connect(service: NetworkService, server: String, port: Int) {
-        val addr = "$server:$port"
-        serviceToAddress[service] = addr
-        val connection = getOrCreateConnection(addr)
-        if (connection.connected || connection.connecting) return
-        connection.connectionJob = reporterScope.launch {
-            try {
-                connection.connecting = true
-                val socket = SocketChannel.open(InetSocketAddress(server, port))
-                connection.socket = socket
-                connection.connected = true
-                println("NetworkReporter: $service connected to $addr")
-            } catch (e: Exception) {
-                println("NetworkReporter connect error: ${e.message}")
-                connection.connected = false
-            } finally {
-                connection.connecting = false
+    init {
+        // Keep only the latest frequency command to avoid stale backlog and effective lag.
+        reporterScope.launch {
+            for (command in frequencyCommands) {
+                ensureFrequencyConnected()
+                if (!frequencyConnected) continue
+                write(frequencySocket, command) { resetFrequencyConnection() }
             }
         }
     }
 
-    private suspend fun write(service: NetworkService, command: String) {
-        val addr = serviceToAddress[service] ?: return
-        val connection = connections[addr] ?: return
-        if (!connection.connected) return
+    override fun reportRotation(format: String, azimuth: Double, elevation: Double) {
+        reporterScope.launch {
+            ensureRotatorConnected()
+            if (!rotatorConnected) return@launch
+            val el = if (elevation > 0.0) elevation else 0.0
+            val command = format
+                .replace($$"$AZ", azimuth.toString())
+                .replace($$"$EL", el.toString())
+                .unescapeControlChars()
+            write(rotatorSocket, command) { resetRotatorConnection() }
+        }
+    }
+
+    override fun reportFrequency(format: String, frequency: Long) {
+        val clampedOffset = frequencyOffsetHz.coerceIn(
+            Constants.FREQ_OFFSET_MIN_HZ,
+            Constants.FREQ_OFFSET_MAX_HZ
+        )
+        val correctedFreq = frequency.coerceAtLeast(0L).safeAdd(clampedOffset).coerceAtLeast(0L)
+        val command = format
+            .replace($$"$FREQ", correctedFreq.toString())
+            .unescapeControlChars()
+        frequencyCommands.trySend(command)
+    }
+
+    private suspend fun ensureRotatorConnected() {
+        connectionMutex.withLock {
+            if (rotatorConnected || rotatorServer.isBlank()) return
+            try {
+                resetRotatorConnection()
+                rotatorSocket = SocketChannel.open(InetSocketAddress(rotatorServer, rotatorPort))
+                rotatorConnected = true
+                println("NetworkReporter: Rotator connected to $rotatorServer:$rotatorPort")
+            } catch (e: Exception) {
+                println("NetworkReporter rotator connect error: ${e.message}")
+                resetRotatorConnection()
+            }
+        }
+    }
+
+    private suspend fun ensureFrequencyConnected() {
+        connectionMutex.withLock {
+            if (frequencyConnected || frequencyServer.isBlank()) return
+            try {
+                resetFrequencyConnection()
+                frequencySocket = SocketChannel.open(InetSocketAddress(frequencyServer, frequencyPort))
+                frequencyConnected = true
+                println("NetworkReporter: Frequency connected to $frequencyServer:$frequencyPort")
+            } catch (e: Exception) {
+                println("NetworkReporter frequency connect error: ${e.message}")
+                resetFrequencyConnection()
+            }
+        }
+    }
+
+    private suspend fun write(socket: SocketChannel?, command: String, onError: () -> Unit) {
         try {
             writeMutex.withLock {
-                val buffer = ByteBuffer.wrap("\\$command\n".toByteArray())
-                connection.socket?.write(buffer)
+                val buffer = ByteBuffer.wrap("$command\n".toByteArray())
+                while (buffer.hasRemaining()) {
+                    socket?.write(buffer)
+                }
             }
         } catch (e: Exception) {
             println("NetworkReporter write error: ${e.message}")
-            connection.connected = false
+            onError()
         }
     }
 
-    override fun isConnected(service: BtService): Boolean = false
+    private fun resetRotatorConnection() {
+        rotatorConnected = false
+        closeQuietly(rotatorSocket)
+        rotatorSocket = null
+    }
 
-    override fun isConnecting(service: BtService): Boolean = false
+    private fun resetFrequencyConnection() {
+        frequencyConnected = false
+        closeQuietly(frequencySocket)
+        frequencySocket = null
+    }
 
-    override fun connect(service: BtService, deviceId: String) {}
+    private fun closeQuietly(socket: SocketChannel?) {
+        try {
+            socket?.close()
+        } catch (_: Exception) {}
+    }
 
-    override fun reportRotation(format: String, azimuth: Double, elevation: Double, params: ExtendedParams) {
-        reporterScope.launch {
-            connect(NetworkService.ROTATOR, params.server, params.port)
-            if (!isConnected(NetworkService.ROTATOR)) return@launch
-            val el = if (elevation > 0.0) elevation else 0.0
-            val command = format
-                .replace("\$AZ", azimuth.toString())
-                .replace("\$EL", el.toString())
-            write(NetworkService.ROTATOR, command)
+    private fun Long.safeAdd(delta: Long): Long {
+        return when {
+            delta > 0 && this > Long.MAX_VALUE - delta -> Long.MAX_VALUE
+            delta < 0 && this < Long.MIN_VALUE - delta -> Long.MIN_VALUE
+            else -> this + delta
         }
     }
 
-    override fun reportFrequency(format: String, frequency: Long, params: ExtendedParams) {
-        reporterScope.launch {
-            connect(NetworkService.FREQUENCY, params.server, params.port)
-            if (!isConnected(NetworkService.FREQUENCY)) return@launch
-            val command = format.replace("\$FREQ", frequency.toString())
-            write(NetworkService.FREQUENCY, command)
-        }
-    }
+    private fun String.unescapeControlChars(): String =
+        replace("""\r""", 13.toChar().toString())
+            .replace("""\n""", 10.toChar().toString())
+            .replace("""\t""", 9.toChar().toString())
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/RadioTrackingService.kt

@@ -0,0 +1,556 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.framework
+
+import android.bluetooth.BluetoothManager
+import android.util.Log
+import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
+import com.rtbishop.look4sat.core.domain.model.SatRadio
+import com.rtbishop.look4sat.core.domain.predict.OrbitalPass
+import com.rtbishop.look4sat.core.domain.predict.SPEED_OF_LIGHT
+import com.rtbishop.look4sat.core.domain.repository.IRadioController
+import com.rtbishop.look4sat.core.domain.repository.IRadioTrackingService
+import com.rtbishop.look4sat.core.domain.repository.ISatelliteRepo
+import com.rtbishop.look4sat.core.domain.repository.ISettingsRepo
+import com.rtbishop.look4sat.core.domain.repository.RadioTrackingState
+import com.rtbishop.look4sat.core.domain.utility.TransponderMapper
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.currentCoroutineContext
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.launch
+
+class RadioTrackingService(
+    private val appScope: CoroutineScope,
+    private val bluetoothManager: BluetoothManager,
+    private val satelliteRepo: ISatelliteRepo,
+    private val settingsRepo: ISettingsRepo
+) : IRadioTrackingService {
+
+    private val tag = "RadioTracking"
+    /** Delay between each step of the split-mode init sequence (ms). */
+    private val INIT_STEP_DELAY_MS = 200L
+    private val _state = MutableStateFlow(RadioTrackingState())
+    override val state: StateFlow<RadioTrackingState> = _state
+
+    private var txController: IRadioController? = null
+    private var rxController: IRadioController? = null
+    private var trackingJob: Job? = null
+
+    // ── Connection ──────────────────────────────────────────────────────────
+
+    override suspend fun connectRadios() {
+        txController?.disconnect()
+        rxController?.disconnect()
+
+        val rcSettings = settingsRepo.radioControlSettings.value
+        val txAddr     = rcSettings.txRadioAddress
+        val rxAddr     = rcSettings.rxRadioAddress
+        val isIcom     = rcSettings.radioModel == RadioControlSettings.MODEL_ICOM_IC705
+        val isSplit    = isIcom && rcSettings.splitMode
+
+        Log.i(tag, "connectRadios model=${rcSettings.radioModel} split=$isSplit TX=$txAddr RX=$rxAddr")
+
+        if (isSplit) {
+            // Single-radio split mode: only TX slot is used
+            if (txAddr.isBlank()) {
+                _state.update { it.copy(errorMessage = "No radio address configured in Settings") }
+                return
+            }
+            val tx = makeController(isIcom, txAddr)
+            txController = tx
+            rxController = null
+            _state.update { it.copy(errorMessage = null) }
+            val txOk = tx.connect()
+            _state.update {
+                it.copy(
+                    txConnected = txOk,
+                    rxConnected = false,
+                    errorMessage = if (!txOk) "Could not connect to radio ($txAddr)" else null
+                )
+            }
+            Log.i(tag, "IC-705 split mode connected: txOk=$txOk")
+        } else {
+            if (txAddr.isBlank() && rxAddr.isBlank()) {
+                _state.update { it.copy(errorMessage = "No radio addresses configured in Settings") }
+                return
+            }
+            val tx = makeController(isIcom, txAddr)
+            val rx = makeController(isIcom, rxAddr)
+            txController = tx
+            rxController = rx
+            _state.update { it.copy(errorMessage = null) }
+            val txOk = if (txAddr.isNotBlank()) tx.connect() else false
+            val rxOk = if (rxAddr.isNotBlank()) rx.connect() else false
+            _state.update {
+                it.copy(
+                    txConnected = txOk,
+                    rxConnected = rxOk,
+                    errorMessage = when {
+                        !txOk && !rxOk -> "Could not connect to TX and RX radios"
+                        !txOk          -> "Could not connect to TX radio ($txAddr)"
+                        !rxOk          -> "Could not connect to RX radio ($rxAddr)"
+                        else           -> null
+                    }
+                )
+            }
+            Log.i(tag, "Dual-radio connected: txOk=$txOk rxOk=$rxOk")
+        }
+    }
+
+    private fun makeController(isIcom: Boolean, address: String): IRadioController =
+        if (isIcom) Ic705Controller(bluetoothManager, address)
+        else        Ft817Controller(bluetoothManager, address)
+
+    override suspend fun disconnectRadios() {
+        stopTracking()
+        txController?.disconnect()
+        rxController?.disconnect()
+        txController = null
+        rxController = null
+        _state.update { it.copy(txConnected = false, rxConnected = false, isActive = false) }
+    }
+
+    // ── Tracking ────────────────────────────────────────────────────────────
+
+    override fun startTracking(pass: OrbitalPass, transponder: SatRadio, txBaseFreqHz: Long?) {
+        _state.update {
+            it.copy(
+                isActive             = true,
+                currentPass          = pass,
+                selectedTransponder  = transponder,
+                txBaseFrequencyHz    = txBaseFreqHz
+            )
+        }
+        trackingJob?.cancel()
+
+        val rcSettings = settingsRepo.radioControlSettings.value
+        val isIcom     = rcSettings.radioModel == RadioControlSettings.MODEL_ICOM_IC705
+        val isSplit    = isIcom && rcSettings.splitMode
+
+        if (isSplit) {
+            trackingJob = appScope.launch { runSplitTracking(transponder, txBaseFreqHz) }
+        } else {
+            trackingJob = appScope.launch { runDualRadioTracking(transponder, txBaseFreqHz) }
+        }
+    }
+
+    // ── Dual-radio tracking (Yaesu or two IC-705s) ──────────────────────────
+
+    private suspend fun runDualRadioTracking(transponder: SatRadio, initialTxBaseFreqHz: Long?) {
+        val tx = txController
+        val rx = rxController
+
+        // Initial setup: set band/mode/CTCSS on both radios
+        val txMode = transponder.uplinkMode
+        val rxMode = transponder.downlinkMode
+            ?: transponder.uplinkMode?.let {
+                TransponderMapper.mapUplinkModeToDownlinkMode(it, transponder.isInverted)
+            }
+
+        Log.i(tag, "DualRadio start: txMode=$txMode rxMode=$rxMode")
+
+        if (tx != null && tx.isConnected && txMode != null) {
+            Log.d(tag, "Setting TX mode: $txMode")
+            tx.setMode(txMode)
+        }
+        if (rx != null && rx.isConnected && rxMode != null) {
+            Log.d(tag, "Setting RX mode: $rxMode")
+            rx.setMode(rxMode)
+        }
+        if (txMode?.uppercase() == "FM") {
+            _state.value.ctcssTone?.let { tone ->
+                Log.d(tag, "Setting CTCSS: ${tone}Hz")
+                tx?.setCtcssTone(tone)
+                tx?.setCtcssMode(true)
+            }
+        }
+        _state.update { it.copy(txMode = txMode, rxMode = rxMode) }
+
+        var lastSetTxFreq = 0.0
+        var lastSetRxFreq = 0.0
+        var tuningRadio   = ""
+        var lastReadFreq  = 0L
+        var stableCount   = 0
+
+        while (currentCoroutineContext().isActive) {
+            val currentState = _state.value
+            if (!currentState.isActive) break
+
+            val satPass = currentState.currentPass ?: break
+            val xpdr    = currentState.selectedTransponder ?: break
+            var txBaseFreq = currentState.txBaseFrequencyHz
+            val stationPos = settingsRepo.stationPosition.value
+            val pos = satelliteRepo.getPosition(satPass.orbitalObject, stationPos, System.currentTimeMillis())
+            val txNow = txController
+            val rxNow = rxController
+            val v = pos.distanceRate * 1000.0
+
+            if (tuningRadio.isNotEmpty()) {
+                val radio = if (tuningRadio == "tx") txNow else rxNow
+                if (radio != null && radio.isConnected) {
+                    val read = radio.readFrequencyAndMode()
+                    if (read != null) {
+                        val (freq, _) = read
+                        if (kotlin.math.abs(freq - lastReadFreq) <= 20) stableCount++
+                        else { stableCount = 0; lastReadFreq = freq }
+                        if (stableCount >= 2) {
+                            if (tuningRadio == "tx" && txBaseFreq != null) {
+                                val newBase = (freq.toDouble() * SPEED_OF_LIGHT / (SPEED_OF_LIGHT + v)).toLong()
+                                if (newBase > 0) {
+                                    txBaseFreq = newBase
+                                    _state.update { it.copy(txBaseFrequencyHz = newBase) }
+                                    Log.i(tag, "TX tuning done → base=$newBase")
+                                }
+                            } else if (tuningRadio == "rx") {
+                                val rxNominal = (freq.toDouble() * SPEED_OF_LIGHT / (SPEED_OF_LIGHT - v)).toLong()
+                                val newTxBase = TransponderMapper.mapDownlinkToUplink(rxNominal, xpdr)
+                                if (newTxBase != null && newTxBase > 0) {
+                                    txBaseFreq = newTxBase
+                                    _state.update { it.copy(txBaseFrequencyHz = newTxBase) }
+                                    Log.i(tag, "RX tuning done → txBase=$newTxBase")
+                                }
+                            }
+                            tuningRadio   = ""
+                            stableCount   = 0
+                            lastSetTxFreq = 0.0
+                            lastSetRxFreq = 0.0
+                        }
+                    }
+                }
+            } else {
+                // Detect manual dial changes
+                if (txBaseFreq != null && txNow != null && txNow.isConnected && lastSetTxFreq > 0.0) {
+                    val read = txNow.readFrequencyAndMode()
+                    if (read != null && kotlin.math.abs(read.first - lastSetTxFreq) >= 20.0) {
+                        tuningRadio  = "tx"
+                        lastReadFreq = read.first
+                        stableCount  = 0
+                        Log.i(tag, "TX tuning detected (read=${read.first}, lastSet=$lastSetTxFreq)")
+                    }
+                }
+                if (tuningRadio.isEmpty() && rxNow != null && rxNow.isConnected && lastSetRxFreq > 0.0) {
+                    val read = rxNow.readFrequencyAndMode()
+                    if (read != null && kotlin.math.abs(read.first - lastSetRxFreq) >= 20.0) {
+                        tuningRadio  = "rx"
+                        lastReadFreq = read.first
+                        stableCount  = 0
+                        Log.i(tag, "RX tuning detected (read=${read.first}, lastSet=$lastSetRxFreq)")
+                    }
+                }
+            }
+
+            val txRadioFreq = txBaseFreq?.let { pos.getUplinkFreq(it) }
+            val rxBaseFreq  = if (txBaseFreq != null) {
+                TransponderMapper.mapUplinkToDownlink(txBaseFreq, xpdr)
+            } else xpdr.downlinkLow
+            val rxRadioFreq = rxBaseFreq?.let { pos.getDownlinkFreq(it) }
+
+            if (tuningRadio.isEmpty()) {
+                if (txNow != null && txNow.isConnected && txRadioFreq != null) {
+                    txNow.setFrequency(txRadioFreq)
+                    lastSetTxFreq = txRadioFreq.toDouble()
+                }
+                if (rxNow != null && rxNow.isConnected && rxRadioFreq != null) {
+                    rxNow.setFrequency(rxRadioFreq)
+                    lastSetRxFreq = rxRadioFreq.toDouble()
+                }
+            }
+
+            _state.update {
+                it.copy(
+                    txConnected  = txNow?.isConnected ?: false,
+                    rxConnected  = rxNow?.isConnected ?: false,
+                    txFrequencyHz = txRadioFreq,
+                    rxFrequencyHz = rxRadioFreq,
+                    azimuth      = Math.toDegrees(pos.azimuth),
+                    elevation    = Math.toDegrees(pos.elevation),
+                    distance     = pos.distance
+                )
+            }
+            delay(1000)
+        }
+    }
+
+    // ── IC-705 split-radio tracking ─────────────────────────────────────────
+
+    private suspend fun runSplitTracking(transponder: SatRadio, initialTxBaseFreqHz: Long?) {
+        val radio = txController ?: return
+        if (!radio.isConnected) return
+
+        val txMode = transponder.uplinkMode
+        val rxMode = transponder.downlinkMode
+            ?: transponder.uplinkMode?.let {
+                TransponderMapper.mapUplinkModeToDownlinkMode(it, transponder.isInverted)
+            }
+
+        // Compute nominal base frequencies
+        val txCenter = when {
+            transponder.uplinkLow != null && transponder.uplinkHigh != null ->
+                (transponder.uplinkLow!! + transponder.uplinkHigh!!) / 2
+            transponder.uplinkLow != null -> transponder.uplinkLow!!
+            else -> null
+        }
+        val rxNominal = if (txCenter != null) {
+            TransponderMapper.mapUplinkToDownlink(txCenter, transponder)
+        } else transponder.downlinkLow
+
+        val txBase = initialTxBaseFreqHz ?: txCenter
+        Log.i(tag, "IC-705 split setup: txBase=${txBase}Hz rxNominal=${rxNominal}Hz txMode=$txMode rxMode=$rxMode")
+
+        // ── Initial setup sequence ──────────────────────────────────────────
+        // Sequence per IC-705: explicitly select VFO, then band → freq → mode.
+        // ACK from each command gates the next — no fixed delays needed.
+
+        // VFO-A = RX (downlink)
+        Log.d(tag, "Split init: selecting VFO-A for RX (downlink)")
+        radio.setVfo(vfoA = true)
+        if (rxNominal != null) {
+            Log.d(tag, "Split init: VFO-A band for ${rxNominal}Hz")
+            radio.setBand(rxNominal)
+            Log.d(tag, "Split init: VFO-A freq=${rxNominal}Hz")
+            radio.setFrequency(rxNominal)
+        }
+        if (rxMode != null) {
+            Log.d(tag, "Split init: VFO-A mode=$rxMode")
+            radio.setMode(rxMode)
+        }
+
+        // VFO-B = TX (uplink)
+        Log.d(tag, "Split init: selecting VFO-B for TX (uplink)")
+        radio.setVfo(vfoA = false)
+        if (txBase != null) {
+            Log.d(tag, "Split init: VFO-B band for ${txBase}Hz")
+            radio.setBand(txBase)
+            Log.d(tag, "Split init: VFO-B freq=${txBase}Hz")
+            radio.setFrequency(txBase)
+        }
+        if (txMode != null) {
+            Log.d(tag, "Split init: VFO-B mode=$txMode")
+            radio.setMode(txMode)
+        }
+        if (txMode?.uppercase() == "FM") {
+            val tone = _state.value.ctcssTone
+            if (tone != null) {
+                Log.d(tag, "Split init: CTCSS=${tone}Hz")
+                radio.setCtcssTone(tone)
+                radio.setCtcssMode(true)
+            } else {
+                radio.setCtcssMode(false)
+            }
+        }
+
+        // Enable SPLIT on VFO-A (return display to RX VFO first)
+        Log.d(tag, "Split init: returning to VFO-A, then enabling SPLIT mode")
+        radio.setVfo(vfoA = true)
+        radio.setSplitMode(enabled = true)
+
+        _state.update { it.copy(txMode = txMode, rxMode = rxMode, txBaseFrequencyHz = txBase) }
+        Log.i(tag, "IC-705 split init done — entering tracking loop")
+
+        // ── Tracking loop with tuning detection ─────────────────────────────
+        var lastSetTxFreq = 0.0
+        var lastSetRxFreq = 0.0
+        var tuningRadio   = ""  // "tx" or "rx" when manual tuning detected
+        var lastReadFreq  = 0L
+        var stableCount   = 0
+
+        while (currentCoroutineContext().isActive) {
+            val currentState = _state.value
+            if (!currentState.isActive) break
+
+            val satPass = currentState.currentPass ?: break
+            val xpdr    = currentState.selectedTransponder ?: break
+            var txBaseFreq = currentState.txBaseFrequencyHz
+            val stationPos = settingsRepo.stationPosition.value
+            val pos = satelliteRepo.getPosition(satPass.orbitalObject, stationPos, System.currentTimeMillis())
+            val v = pos.distanceRate * 1000.0
+
+            if (tuningRadio.isNotEmpty()) {
+                // User is tuning — wait for frequency to stabilize
+                val readFreq = if (tuningRadio == "tx") radio.readTxVfoFrequency() else radio.readWorkingFrequency()
+                if (readFreq != null) {
+                    if (kotlin.math.abs(readFreq - lastReadFreq) <= 20) stableCount++
+                    else { stableCount = 0; lastReadFreq = readFreq }
+
+                    if (stableCount >= 2) {
+                        // Frequency stable — reverse-calculate base frequency
+                        if (tuningRadio == "tx" && txBaseFreq != null) {
+                            val newBase = (readFreq.toDouble() * SPEED_OF_LIGHT / (SPEED_OF_LIGHT + v)).toLong()
+                            if (newBase > 0) {
+                                txBaseFreq = newBase
+                                _state.update { it.copy(txBaseFrequencyHz = newBase) }
+                                Log.i(tag, "Split TX tuning done → base=$newBase")
+                            }
+                        } else if (tuningRadio == "rx") {
+                            val rxNominal = (readFreq.toDouble() * SPEED_OF_LIGHT / (SPEED_OF_LIGHT - v)).toLong()
+                            val newTxBase = TransponderMapper.mapDownlinkToUplink(rxNominal, xpdr)
+                            if (newTxBase != null && newTxBase > 0) {
+                                txBaseFreq = newTxBase
+                                _state.update { it.copy(txBaseFrequencyHz = newTxBase) }
+                                Log.i(tag, "Split RX tuning done → txBase=$newTxBase")
+                            }
+                        }
+                        tuningRadio   = ""
+                        stableCount   = 0
+                        lastSetTxFreq = 0.0
+                        lastSetRxFreq = 0.0
+                    }
+                }
+            } else {
+                // Detect manual dial changes
+                if (txBaseFreq != null && lastSetTxFreq > 0.0) {
+                    val readTx = radio.readTxVfoFrequency()
+                    if (readTx != null && kotlin.math.abs(readTx - lastSetTxFreq) >= 20.0) {
+                        tuningRadio  = "tx"
+                        lastReadFreq = readTx
+                        stableCount  = 0
+                        Log.i(tag, "Split TX tuning detected (read=${readTx}, lastSet=$lastSetTxFreq)")
+                    }
+                }
+                if (tuningRadio.isEmpty() && lastSetRxFreq > 0.0) {
+                    val readRx = radio.readWorkingFrequency()
+                    if (readRx != null && kotlin.math.abs(readRx - lastSetRxFreq) >= 20.0) {
+                        tuningRadio  = "rx"
+                        lastReadFreq = readRx
+                        stableCount  = 0
+                        Log.i(tag, "Split RX tuning detected (read=${readRx}, lastSet=$lastSetRxFreq)")
+                    }
+                }
+            }
+
+            // Determine Doppler-corrected frequencies
+            val txRadioFreq = txBaseFreq?.let { pos.getUplinkFreq(it) }
+            val rxBaseCalc  = if (txBaseFreq != null) {
+                TransponderMapper.mapUplinkToDownlink(txBaseFreq, xpdr)
+            } else xpdr.downlinkLow
+            val rxRadioFreq = rxBaseCalc?.let { pos.getDownlinkFreq(it) }
+
+            if (radio.isConnected && tuningRadio.isEmpty()) {
+                // Update both VFOs every cycle — no PTT polling needed.
+                // 0x25/00 = active (RX) VFO, 0x25/01 = inactive (TX) VFO.
+                if (rxRadioFreq != null) {
+                    Log.d(tag, "Split loop RX (0x25/00): ${rxRadioFreq}Hz")
+                    radio.setWorkingFrequency(rxRadioFreq)
+                    lastSetRxFreq = rxRadioFreq.toDouble()
+                }
+                if (txRadioFreq != null) {
+                    Log.d(tag, "Split loop TX (0x25/01): ${txRadioFreq}Hz")
+                    radio.setTxVfoFrequency(txRadioFreq)
+                    lastSetTxFreq = txRadioFreq.toDouble()
+                }
+            }
+
+            _state.update {
+                it.copy(
+                    txConnected   = radio.isConnected,
+                    rxConnected   = false,  // single radio
+                    txFrequencyHz = txRadioFreq,
+                    rxFrequencyHz = rxRadioFreq,
+                    azimuth       = Math.toDegrees(pos.azimuth),
+                    elevation     = Math.toDegrees(pos.elevation),
+                    distance      = pos.distance
+                )
+            }
+            delay(1000)
+        }
+    }
+
+    // ── Other IRadioTrackingService methods ─────────────────────────────────
+
+    override fun stopTracking() {
+        trackingJob?.cancel()
+        trackingJob = null
+        _state.update { it.copy(isActive = false) }
+    }
+
+    override fun setTransponder(transponder: SatRadio) {
+        appScope.launch {
+            val tx = txController
+            val rx = rxController
+            transponder.uplinkMode?.let { tx?.setMode(it) }
+            val rxMode = transponder.downlinkMode
+                ?: transponder.uplinkMode?.let {
+                    TransponderMapper.mapUplinkModeToDownlinkMode(it, transponder.isInverted)
+                }
+            rxMode?.let { rx?.setMode(it) }
+            if (transponder.uplinkMode?.uppercase() == "FM") {
+                _state.value.ctcssTone?.let { tone ->
+                    tx?.setCtcssTone(tone)
+                    tx?.setCtcssMode(true)
+                }
+            }
+        }
+        val txCenter = when {
+            transponder.uplinkLow != null && transponder.uplinkHigh != null ->
+                (transponder.uplinkLow!! + transponder.uplinkHigh!!) / 2
+            transponder.uplinkLow != null -> transponder.uplinkLow!!
+            else -> null
+        }
+        val rxNominal = if (txCenter != null) {
+            TransponderMapper.mapUplinkToDownlink(txCenter, transponder)
+        } else transponder.downlinkLow
+        _state.update {
+            it.copy(
+                selectedTransponder = transponder,
+                txBaseFrequencyHz   = txCenter,
+                txFrequencyHz       = txCenter,
+                rxFrequencyHz       = rxNominal,
+                txMode              = transponder.uplinkMode,
+                rxMode              = transponder.downlinkMode
+                    ?: transponder.uplinkMode?.let { m ->
+                        TransponderMapper.mapUplinkModeToDownlinkMode(m, transponder.isInverted)
+                    }
+            )
+        }
+    }
+
+    override fun setTxBaseFrequency(frequencyHz: Long) {
+        _state.update { it.copy(txBaseFrequencyHz = frequencyHz) }
+    }
+
+    override fun adjustTxBaseFrequency(deltaHz: Long) {
+        val current = _state.value.txBaseFrequencyHz ?: return
+        _state.update { it.copy(txBaseFrequencyHz = current + deltaHz) }
+    }
+
+    override fun setCtcssTone(toneHz: Double?) {
+        _state.update { it.copy(ctcssTone = toneHz) }
+        appScope.launch {
+            val tx = txController
+            if (toneHz != null) {
+                tx?.setCtcssTone(toneHz)
+                tx?.setCtcssMode(true)
+            } else {
+                tx?.setCtcssMode(false)
+            }
+        }
+    }
+
+    override fun setMode(txMode: String, rxMode: String) {
+        appScope.launch {
+            txController?.setMode(txMode)
+            rxController?.setMode(rxMode)
+        }
+        _state.update { it.copy(txMode = txMode, rxMode = rxMode) }
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/injection/MainContainer.kt

@@ -1,72 +1,161 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
 package com.rtbishop.look4sat.core.data.injection
 
 import android.bluetooth.BluetoothManager
 import android.content.Context
-import android.hardware.Sensor
 import android.hardware.SensorManager
+import android.hardware.display.DisplayManager
 import android.location.LocationManager
-import android.view.WindowManager
 import androidx.room.Room
 import com.rtbishop.look4sat.core.data.database.Look4SatDb
 import com.rtbishop.look4sat.core.data.framework.BluetoothReporter
+import com.rtbishop.look4sat.core.data.framework.Ft817Controller
+import com.rtbishop.look4sat.core.data.framework.Ic705Controller
 import com.rtbishop.look4sat.core.data.framework.NetworkReporter
+import com.rtbishop.look4sat.core.data.framework.RadioTrackingService
+import com.rtbishop.look4sat.core.data.repository.AmSatRepository
 import com.rtbishop.look4sat.core.data.repository.DatabaseRepo
 import com.rtbishop.look4sat.core.data.repository.SatelliteRepo
 import com.rtbishop.look4sat.core.data.repository.SelectionRepo
 import com.rtbishop.look4sat.core.data.repository.SensorsRepo
 import com.rtbishop.look4sat.core.data.repository.SettingsRepo
+import com.rtbishop.look4sat.core.data.repository.UpdateRepository
+import com.rtbishop.look4sat.core.data.repository.LoTWRepository
+import com.rtbishop.look4sat.core.data.repository.WavelogRepository
 import com.rtbishop.look4sat.core.data.source.LocalSource
 import com.rtbishop.look4sat.core.data.source.RemoteSource
 import com.rtbishop.look4sat.core.data.usecase.AddToCalendar
+import com.rtbishop.look4sat.core.data.usecase.AudioCapture
+import com.rtbishop.look4sat.core.data.usecase.SaveImage
 import com.rtbishop.look4sat.core.data.usecase.ShowToast
-import com.rtbishop.look4sat.core.domain.repository.ExtendedParams
+import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
 import com.rtbishop.look4sat.core.domain.repository.IDatabaseRepo
 import com.rtbishop.look4sat.core.domain.repository.IMainContainer
-import com.rtbishop.look4sat.core.domain.repository.IReporterRepo
+import com.rtbishop.look4sat.core.domain.repository.IRadioController
+import com.rtbishop.look4sat.core.domain.repository.IRadioTrackingService
+import com.rtbishop.look4sat.core.domain.repository.IReporter
+import com.rtbishop.look4sat.core.domain.repository.ILoTWRepository
 import com.rtbishop.look4sat.core.domain.repository.ISatelliteRepo
 import com.rtbishop.look4sat.core.domain.repository.ISelectionRepo
 import com.rtbishop.look4sat.core.domain.repository.ISensorsRepo
 import com.rtbishop.look4sat.core.domain.repository.ISettingsRepo
-import com.rtbishop.look4sat.core.domain.repository.WithoutExtParams
+import com.rtbishop.look4sat.core.domain.repository.IWavelogRepository
+import com.rtbishop.look4sat.core.domain.repository.MutualPassData
 import com.rtbishop.look4sat.core.domain.source.ILocalSource
 import com.rtbishop.look4sat.core.domain.source.IRemoteSource
 import com.rtbishop.look4sat.core.domain.usecase.IAddToCalendar
+import com.rtbishop.look4sat.core.domain.usecase.IAudioCapture
+import com.rtbishop.look4sat.core.domain.usecase.ISaveImage
 import com.rtbishop.look4sat.core.domain.usecase.IShowToast
 import com.rtbishop.look4sat.core.domain.utility.DataParser
 import kotlinx.coroutines.CoroutineExceptionHandler
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
 import okhttp3.OkHttpClient
 
 class MainContainer(private val context: Context) : IMainContainer {
 
     private val localSource = provideLocalSource()
+    private val remoteSource = provideRemoteSource()
     private val mainHandler = CoroutineExceptionHandler { _, error -> println("MainHandler: $error") }
     override val appScope = CoroutineScope(SupervisorJob() + Dispatchers.Default + mainHandler)
     override val settingsRepo = provideSettingsRepo()
     override val selectionRepo = provideSelectionRepo()
     override val satelliteRepo = provideSatelliteRepo()
     override val databaseRepo = provideDatabaseRepo()
+    override val amSatRepo by lazy { AmSatRepository(remoteSource, appScope) }
+    override val updateRepo by lazy { UpdateRepository(remoteSource) }
+    override val wavelogRepo: IWavelogRepository by lazy { WavelogRepository() }
+    override val lotwRepo: ILoTWRepository by lazy { LoTWRepository() }
+    override val radioTrackingService: IRadioTrackingService by lazy {
+        val manager = context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
+        RadioTrackingService(appScope, manager, satelliteRepo, settingsRepo)
+    }
+
+    private val _mutualPassData = MutableStateFlow(MutualPassData())
+    override val mutualPassData: StateFlow<MutualPassData> = _mutualPassData.asStateFlow()
+
+    override fun setMutualPassData(data: MutualPassData) {
+        _mutualPassData.value = data
+    }
 
     override fun provideAddToCalendar(): IAddToCalendar = AddToCalendar(context)
 
     override fun provideShowToast(): IShowToast = ShowToast(context)
 
-    override fun provideBluetoothReporter(): IReporterRepo<WithoutExtParams> {
+    override fun provideAudioCapture(): IAudioCapture = AudioCapture()
+
+    override fun provideSaveImage(): ISaveImage = SaveImage(context)
+
+    override fun provideBluetoothReporter(): IReporter {
         val manager = context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
-        return BluetoothReporter(manager, CoroutineScope(Dispatchers.IO))
+        val rc = settingsRepo.rcSettings.value
+        return BluetoothReporter(
+            manager,
+            CoroutineScope(Dispatchers.IO),
+            rc.bluetoothRotatorAddress,
+            rc.bluetoothFrequencyAddress
+        )
     }
 
-    override fun provideNetworkReporter(): IReporterRepo<ExtendedParams> {
-        return NetworkReporter(CoroutineScope(Dispatchers.IO))
+    override fun provideNetworkReporter(): IReporter {
+        val rc = settingsRepo.rcSettings.value
+        return NetworkReporter(
+            CoroutineScope(Dispatchers.IO),
+            rc.rotatorAddress,
+            rc.rotatorPort.toIntOrNull() ?: 0,
+            rc.frequencyAddress,
+            rc.frequencyPort.toIntOrNull() ?: 0,
+            rc.frequencyOffsetHz
+        )
+    }
+
+    override fun provideTxRadioController(): IRadioController {
+        val manager  = context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
+        val settings = settingsRepo.radioControlSettings.value
+        val address  = settings.txRadioAddress
+        return if (settings.radioModel == RadioControlSettings.MODEL_ICOM_IC705) {
+            Ic705Controller(manager, address)
+        } else {
+            Ft817Controller(manager, address)
+        }
+    }
+
+    override fun provideRxRadioController(): IRadioController {
+        val manager  = context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
+        val settings = settingsRepo.radioControlSettings.value
+        val address  = settings.rxRadioAddress
+        return if (settings.radioModel == RadioControlSettings.MODEL_ICOM_IC705) {
+            Ic705Controller(manager, address)
+        } else {
+            Ft817Controller(manager, address)
+        }
     }
 
     override fun provideSensorsRepo(): ISensorsRepo {
         val manager = context.getSystemService(Context.SENSOR_SERVICE) as SensorManager
-        val sensor = manager.getDefaultSensor(Sensor.TYPE_ROTATION_VECTOR)
-        val window = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
-        return SensorsRepo(manager,sensor,window)
+        val displayManager = context.getSystemService(DisplayManager::class.java)
+        return SensorsRepo(manager, displayManager)
     }
 
     private fun provideDatabaseRepo(): IDatabaseRepo {

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/AmSatRepository.kt

@@ -0,0 +1,273 @@
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.model.AmSatReportSubmission
+import com.rtbishop.look4sat.core.domain.model.AmSatReportSubmitResult
+import com.rtbishop.look4sat.core.domain.model.SatDay
+import com.rtbishop.look4sat.core.domain.model.SatReport
+import com.rtbishop.look4sat.core.domain.model.SatSlot
+import com.rtbishop.look4sat.core.domain.model.SatStatus
+import com.rtbishop.look4sat.core.domain.model.SatStatusPage
+import com.rtbishop.look4sat.core.domain.repository.IAmSatRepository
+import com.rtbishop.look4sat.core.domain.source.IRemoteSource
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Deferred
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.async
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import kotlinx.coroutines.withContext
+import org.json.JSONObject
+import java.text.SimpleDateFormat
+import java.util.Calendar
+import java.util.Date
+import java.util.Locale
+import java.util.TimeZone
+
+/** One report from the AMSAT API (data layer model). */
+private data class ApiReport(
+    val id: String,
+    val name: String,
+    val callsign: String,
+    val report: String,
+    val gridSquare: String,
+    val reportedTimeUtcSec: Long
+)
+
+/** AMSAT status repository using RemoteSource (Clean Architecture: data layer handles HTTP). */
+class AmSatRepository(
+    private val remoteSource: IRemoteSource,
+    private val scope: CoroutineScope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
+) : IAmSatRepository {
+
+    private val statusCacheMutex = Mutex()
+
+    @Volatile
+    private var statusCache: SatStatusPage? = null
+
+    @Volatile
+    private var statusFetchInFlight: Deferred<SatStatusPage?>? = null
+
+    @Volatile
+    private var cacheGeneration = 0
+
+    private val isoUtcFormat = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'", Locale.US).apply {
+        timeZone = TimeZone.getTimeZone("UTC")
+    }
+
+    override fun getCachedStatus(): SatStatusPage? = statusCache
+
+    override suspend fun fetchStatus(forceRefresh: Boolean): SatStatusPage? {
+        if (!forceRefresh) statusCache?.let { return it }
+
+        var cachedPage: SatStatusPage? = null
+        val inFlightFetch = statusCacheMutex.withLock {
+            if (!forceRefresh) {
+                val cached = statusCache
+                if (cached != null) {
+                    cachedPage = cached
+                    return@withLock null
+                }
+            }
+
+            statusFetchInFlight ?: scope.async(Dispatchers.IO) {
+                fetchStatusFromRemote(cacheGeneration)
+            }.also { statusFetchInFlight = it }
+        }
+
+        cachedPage?.let { return it }
+        val fetch = inFlightFetch ?: return null
+        return try {
+            fetch.await()
+        } finally {
+            statusCacheMutex.withLock {
+                if (statusFetchInFlight === fetch && fetch.isCompleted) statusFetchInFlight = null
+            }
+        }
+    }
+
+    private suspend fun fetchStatusFromRemote(generation: Int): SatStatusPage? {
+        val nowSec = System.currentTimeMillis() / 1000
+        val catalogJson = remoteSource.getAmSatCatalog() ?: return null
+        // 72h = 3 days; API hard cap is limit=500 regardless of what we send.
+        // 500 records across ~100 catalog satellites ≈ ~1-5 reports/satellite/day — enough for 3 days.
+        // Upgrade path: paginate or request AMSAT to raise the cap if catalog grows beyond ~200 sats.
+        val reportsJson = remoteSource.getAmSatReports(hours = 72, limit = 500) ?: return null
+
+        val names = parseCatalog(catalogJson)
+        val reports = parseReports(reportsJson)
+
+        if (names.isEmpty() && reports.isEmpty()) return null
+
+        val statuses = buildStatuses(names, reports, nowSec)
+        val reportMap = reports.associate { it.id to toSatReport(it) }
+        return SatStatusPage(System.currentTimeMillis(), statuses, reportMap).also { page ->
+            if (generation == cacheGeneration) statusCache = page
+        }
+    }
+
+    override suspend fun prefetchStatus() {
+        fetchStatus(forceRefresh = false)
+    }
+
+    override fun clearStatusCache() {
+        cacheGeneration += 1
+        statusCache = null
+        statusFetchInFlight = null
+    }
+
+    override suspend fun submitReport(submission: AmSatReportSubmission): AmSatReportSubmitResult = withContext(Dispatchers.IO) {
+        val payload = JSONObject().apply {
+            put("name", submission.name)
+            put("report", submission.report)
+            put("callsign", submission.callsign)
+            put("reported_at", isoUtcFormat.format(Date(submission.reportedAtUtcMillis)))
+            if (submission.gridSquare.isNotBlank()) put("grid_square", submission.gridSquare)
+        }
+        val response = remoteSource.submitAmSatReport(payload.toString())
+            ?: return@withContext AmSatReportSubmitResult(success = false, message = "Network request failed")
+        val (code, body) = response
+        val errorMessage = parseSubmitError(body)
+        return@withContext if (code in 200..299 && errorMessage.isBlank()) {
+            AmSatReportSubmitResult(success = true, reportId = parseSubmitReportId(body))
+        } else {
+            AmSatReportSubmitResult(
+                success = false,
+                message = errorMessage.ifBlank { "HTTP $code" }
+            )
+        }
+    }
+
+    private fun parseSubmitError(json: String): String {
+        return try {
+            JSONObject(json).optJSONObject("error")?.optString("message").orEmpty()
+        } catch (_: Exception) {
+            ""
+        }
+    }
+
+    private fun parseSubmitReportId(json: String): String? {
+        return try {
+            val obj = JSONObject(json)
+            obj.optJSONObject("data")?.optString("id")?.takeIf { it.isNotBlank() }
+                ?: obj.optString("id").takeIf { it.isNotBlank() }
+        } catch (_: Exception) {
+            null
+        }
+    }
+
+    /** Parse catalog JSON to list of satellite names */
+    private fun parseCatalog(json: String): List<String> {
+        return try {
+            val arr = JSONObject(json).getJSONArray("data")
+            (0 until arr.length()).map { arr.getJSONObject(it).getString("name") }
+        } catch (_: Exception) {
+            emptyList()
+        }
+    }
+
+    /** Parse reports JSON to list of ApiReport domain objects */
+    private fun parseReports(json: String): List<ApiReport> {
+        return try {
+            val arr = JSONObject(json).getJSONArray("data")
+            (0 until arr.length()).mapNotNull { i ->
+                val o = arr.getJSONObject(i)
+                val iso = o.optString("reported_time", "")
+                if (iso.isEmpty()) null else ApiReport(
+                    id = o.optString("id", ""),
+                    name = o.optString("name", ""),
+                    callsign = o.optString("callsign", ""),
+                    report = o.optString("report", ""),
+                    gridSquare = o.optString("grid_square", ""),
+                    reportedTimeUtcSec = parseIsoUtcSec(iso)
+                )
+            }
+        } catch (_: Exception) {
+            emptyList()
+        }
+    }
+
+    /** Parse ISO 8601 UTC timestamp to epoch seconds (e.g., "2026-08-05T07:30:00Z") */
+    private fun parseIsoUtcSec(iso: String): Long {
+        return try {
+            (isoUtcFormat.parse(iso)?.time ?: 0L) / 1000
+        } catch (_: Exception) {
+            0L
+        }
+    }
+
+    /** Build one SatStatus (3 days x 12 slots) per catalog satellite, slotting reports by age. */
+    private fun buildStatuses(names: List<String>, reports: List<ApiReport>, nowSec: Long): List<SatStatus> {
+        val byName = reports.groupBy { it.name }
+        val utc = Calendar.getInstance(TimeZone.getTimeZone("UTC"))
+        val labels = (0 until 3).map { d ->
+            utc.timeInMillis = (nowSec - d * 86400L) * 1000
+            formatDayLabel(utc)
+        }
+        return names.map { name ->
+            val slots = (0 until 36).map { slotIdx ->
+                val slotStart = nowSec - (slotIdx + 1) * 7200L
+                val slotEnd = nowSec - slotIdx * 7200L
+                val inSlot = byName[name].orEmpty().filter { it.reportedTimeUtcSec in slotStart until slotEnd }
+                if (inSlot.isEmpty()) {
+                    SatSlot(statusColor = NO_REPORT_GRAY, count = 0)
+                } else {
+                    val newest = inSlot.maxByOrNull { it.reportedTimeUtcSec }!!
+                    SatSlot(
+                        statusColor = statusColorOf(newest.report),
+                        count = inSlot.size,
+                        reportIds = inSlot.map { it.id }
+                    )
+                }
+            }
+            val days = (0 until 3).map { d ->
+                SatDay(dateLabel = labels[d], slots = slots.subList(d * 12, (d + 1) * 12))
+            }
+            SatStatus(name = name, days = days)
+        }
+    }
+
+    private fun formatDayLabel(calendar: Calendar): String {
+        return if (Locale.getDefault().language == Locale.CHINESE.language) {
+            "${calendar.get(Calendar.MONTH) + 1}月${calendar.get(Calendar.DAY_OF_MONTH)}日"
+        } else {
+            val monthAbbr = arrayOf("Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec")
+            "${monthAbbr[calendar.get(Calendar.MONTH)]} ${calendar.get(Calendar.DAY_OF_MONTH)}"
+        }
+    }
+
+    private fun toSatReport(r: ApiReport): SatReport {
+        val cal = Calendar.getInstance(TimeZone.getTimeZone("UTC"))
+        cal.timeInMillis = r.reportedTimeUtcSec * 1000
+        val hh = cal.get(Calendar.HOUR_OF_DAY).toString().padStart(2, '0')
+        val mm = cal.get(Calendar.MINUTE).toString().padStart(2, '0')
+        val y = cal.get(Calendar.YEAR)
+        val mo = (cal.get(Calendar.MONTH) + 1).toString().padStart(2, '0')
+        val d = cal.get(Calendar.DAY_OF_MONTH).toString().padStart(2, '0')
+        return SatReport(
+            id = r.id,
+            statusText = r.report,
+            call = r.callsign,
+            grid = r.gridSquare,
+            dateUtc = "$y-$mo-$d",
+            timeUtc = "$hh:$mm UTC"
+        )
+    }
+
+    /** Map status text to color value (for UI rendering). */
+    private fun statusColorOf(report: String): Long = when (report.lowercase()) {
+        "heard", "crew active" -> ACTIVE_BLUE
+        "telemetry only" -> TLM_ORANGE
+        "not heard" -> NOT_HEARD_PINK
+        else -> CONFLICT_DEEP_ORANGE
+    }
+
+    companion object {
+        // AMSAT official status colors (from amsat.org/status)
+        private const val ACTIVE_BLUE = 0xFF648FFF
+        private const val TLM_ORANGE = 0xFFFFB000
+        private const val NOT_HEARD_PINK = 0xFFDC267F
+        private const val CONFLICT_DEEP_ORANGE = 0xFFFE6100
+        private const val NO_REPORT_GRAY = 0xFFC0C0C0
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/DatabaseRepo.kt

@@ -18,7 +18,6 @@
 package com.rtbishop.look4sat.core.data.repository
 
 import com.rtbishop.look4sat.core.domain.model.DatabaseState
-import com.rtbishop.look4sat.core.domain.model.SatRadio
 import com.rtbishop.look4sat.core.domain.predict.OrbitalData
 import com.rtbishop.look4sat.core.domain.repository.IDatabaseRepo
 import com.rtbishop.look4sat.core.domain.repository.ISettingsRepo
@@ -28,7 +27,9 @@ import com.rtbishop.look4sat.core.domain.source.Sources
 import com.rtbishop.look4sat.core.domain.utility.DataParser
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.async
+import kotlinx.coroutines.awaitAll
 import kotlinx.coroutines.withContext
+import java.io.InputStream
 import java.util.zip.ZipInputStream
 
 class DatabaseRepo(
@@ -39,78 +40,72 @@ class DatabaseRepo(
     private val settingsRepo: ISettingsRepo
 ) : IDatabaseRepo {
 
-    override suspend fun updateTLEFromFile(uri: String) = withContext(dispatcher) {
-        val importedSatellites = remoteSource.getFileStream(uri)?.let { dataParser.parseTLEStream(it) }
-        importedSatellites?.let { localSource.insertEntries(it) }
-        setUpdateSuccessful(System.currentTimeMillis())
-    }
+    private val customSourceType = "Other"
 
-    override suspend fun updateTransceiversFromFile(uri: String) = withContext(dispatcher) {
-        val radios = remoteSource.getFileStream(uri)?.let { dataParser.parseJSONStream(it) }
-        radios?.let {
-            if(it.isNotEmpty()) {
-                localSource.deleteRadios()
-                localSource.insertRadios(it)
-            }
+    override suspend fun updateTLEFromFile(uri: String): Int = withContext(dispatcher) {
+        var importedCount = 0
+        remoteSource.getFileStream(uri)?.let { stream ->
+            val entries = parseSatelliteStream(uri, unwrapIfZipped(uri, stream))
+            localSource.insertEntries(entries)
+            settingsRepo.setSatelliteTypeIds(customSourceType, entries.map { it.catnum })
+            importedCount = entries.size
         }
         setUpdateSuccessful(System.currentTimeMillis())
+        importedCount
+    }
+
+    override suspend fun updateTransceiversFromFile(uri: String): Int = withContext(dispatcher) {
+        var importedCount = 0
+        remoteSource.getFileStream(uri)?.let { stream ->
+            val transceivers = dataParser.parseJSONStream(unwrapIfZipped(uri, stream))
+            localSource.insertRadios(transceivers)
+            importedCount = transceivers.size
+        }
+        setUpdateSuccessful(System.currentTimeMillis())
+        importedCount
     }
 
     override suspend fun updateFromRemote() = withContext(dispatcher) {
-        val importedEntries = mutableListOf<OrbitalData>()
-        val importedRadios = mutableListOf<SatRadio>()
-        val tleUrls = Sources.satelliteDataUrls.toMutableMap().apply {
-            if (settingsRepo.dataSourcesSettings.value.useCustomTLE) {
-                this["Other"] = settingsRepo.dataSourcesSettings.value.tleUrl
-            }
-        }
-        val jobsMap = tleUrls
-            .filter { (_, url) -> url.isNotEmpty() }
-            .mapValues { (_, url) -> async { remoteSource.getNetworkStream(url) } }
-        val radioUrls = buildList {
-            add(Sources.RADIO_DATA_URL)
-            if (settingsRepo.dataSourcesSettings.value.useCustomTransceivers) {
-                add(settingsRepo.dataSourcesSettings.value.transceiversUrl)
-            }
-        }
-        val jobRadios = radioUrls.associateWith { url -> async { remoteSource.getNetworkStream(url) } }
-        // parse
-        jobsMap.mapValues { job -> job.value.await() }.forEach { entry ->
-            entry.value?.let { stream ->
-                when (val type = entry.key) {
-                    "Amsat", "R4UAB", "Other" -> {
-                        // parse tle stream
-                        val satellites = dataParser.parseTLEStream(stream)
-                        val catnums = satellites.map { it.catnum }
-                        settingsRepo.setSatelliteTypeIds(type, catnums)
-                        importedEntries.addAll(satellites)
-                    }
-
-                    "McCants", "Classified" -> {
-                        // unzip and parse tle stream
-                        val unzipped = ZipInputStream(stream).apply { nextEntry }
-                        val satellites = dataParser.parseTLEStream(unzipped)
-                        val catnums = satellites.map { it.catnum }
-                        settingsRepo.setSatelliteTypeIds(type, catnums)
-                        importedEntries.addAll(satellites)
-                    }
-
-                    else -> {
-                        // parse csv stream
-                        val satellites = dataParser.parseCSVStream(stream)
-                        val catnums = satellites.map { it.catnum }
-                        settingsRepo.setSatelliteTypeIds(type, catnums)
-                        importedEntries.addAll(satellites)
-                    }
-                }
-            }
-        }
-        jobRadios.values.forEach { job ->
-            job.await()?.let {
-                importedRadios.addAll(dataParser.parseJSONStream(it))
-            }
-        }
-        // insert
+        val settings = settingsRepo.dataSourcesSettings.value
+        // Keep the raw URL as the status key (matches what the settings UI
+        // displays) while requesting with the normalized URL.
+        val tleUrls = settings.satelliteUrls
+            .filterIndexed { i, url -> url.isNotBlank() && settings.isSatelliteEnabled(i) }
+            .map { it to normalizeUrl(it) }
+            .distinctBy { it.second }
+        val radioUrls = settings.transceiversUrls
+            .filterIndexed { i, url -> url.isNotBlank() && settings.isTransceiverEnabled(i) }
+            .map { it to normalizeUrl(it) }
+            .distinctBy { it.second }
+        val builtinTypesByUrl = Sources.satelliteDataUrls
+            .filterValues { it.isNotBlank() }
+            .mapValues { normalizeUrl(it.value) }
+            .entries
+            .associate { (type, url) -> url to type }
+        val importedTypeIds = mutableMapOf<String, MutableList<Int>>()
+        // launch all network requests concurrently, keeping the raw url as key for status reporting
+        val tleJobs = tleUrls.map { (raw, norm) -> async { raw to remoteSource.getNetworkStream(norm) } }
+        val radioJobs = radioUrls.map { (raw, norm) -> async { raw to remoteSource.getNetworkStream(norm) } }
+        val tleResults = tleJobs.awaitAll()
+        val radioResults = radioJobs.awaitAll()
+        // report the HTTP status code of every source (200, 404, ...)
+        settingsRepo.updateDataSourcesStatus(
+            (tleResults + radioResults).associate { (url, result) -> url to result.code }
+        )
+        // parse fetched data concurrently and associate known built-in URLs with existing type filters.
+        val importedEntries = tleResults.flatMap { (rawUrl, result) ->
+            val normUrl = normalizeUrl(rawUrl)
+            val entries = result.stream?.let { parseSatelliteStream(normUrl, unwrapIfZipped(normUrl, it)) }.orEmpty()
+            val type = builtinTypesByUrl[normUrl] ?: customSourceType
+            importedTypeIds.getOrPut(type) { mutableListOf() }.addAll(entries.map { it.catnum })
+            entries
+        }.distinctBy { it.catnum }
+        importedTypeIds.forEach { (type, ids) -> settingsRepo.setSatelliteTypeIds(type, ids.distinct()) }
+        val importedRadios = radioResults.flatMap { (rawUrl, result) ->
+            val normUrl = normalizeUrl(rawUrl)
+            result.stream?.let { dataParser.parseJSONStream(unwrapIfZipped(normUrl, it)) }.orEmpty()
+        }.filter { it.uuid.isNotBlank() }.distinctBy { it.uuid }
+        // insert parsed data into the database
         localSource.insertEntries(importedEntries)
         localSource.insertRadios(importedRadios)
         setUpdateSuccessful(System.currentTimeMillis())
@@ -122,9 +117,42 @@ class DatabaseRepo(
         setUpdateSuccessful(0L)
     }
 
-    private suspend fun setUpdateSuccessful(timestamp: Long) = withContext(dispatcher) {
-        val numberOfRadios = localSource.getRadiosTotal()
-        val numberOfSatellites = localSource.getEntriesTotal()
-        settingsRepo.updateDatabaseState(DatabaseState(numberOfRadios, numberOfSatellites, timestamp))
+    private fun normalizeUrl(url: String): String =
+        if (url.startsWith("http", ignoreCase = true)) url else "https://$url"
+
+    private suspend fun parseSatelliteStream(url: String, stream: InputStream): List<OrbitalData> {
+        val bufferedStream = stream.buffered()
+        return when {
+            hasCsvHint(url) || looksLikeCsv(bufferedStream) -> dataParser.parseCSVStream(bufferedStream)
+            else -> dataParser.parseTLEStream(bufferedStream)
+        }
     }
+
+    private fun hasCsvHint(url: String): Boolean {
+        return url.contains("FORMAT=csv", ignoreCase = true) ||
+            url.endsWith(".csv", ignoreCase = true) ||
+            url.endsWith(".csv.zip", ignoreCase = true)
+    }
+
+    private fun looksLikeCsv(stream: InputStream): Boolean {
+        if (!stream.markSupported()) return false
+        stream.mark(4096)
+        val preview = ByteArray(4096)
+        val length = stream.read(preview)
+        stream.reset()
+        if (length <= 0) return false
+        val line = preview.decodeToString(0, length).lineSequence().firstOrNull()?.trim().orEmpty()
+        return line.contains("OBJECT_NAME", ignoreCase = true) ||
+            line.contains("NORAD_CAT_ID", ignoreCase = true) ||
+            line.count { it == ',' } >= 4
+    }
+
+    private suspend fun setUpdateSuccessful(timestamp: Long) {
+        settingsRepo.updateDatabaseState(
+            DatabaseState(localSource.getRadiosTotal(), localSource.getEntriesTotal(), timestamp)
+        )
+    }
+
+    private fun unwrapIfZipped(url: String, stream: InputStream): InputStream =
+        if (url.endsWith(".zip", ignoreCase = true)) ZipInputStream(stream).apply { nextEntry } else stream
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/LoTWRepository.kt

@@ -0,0 +1,300 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.repository.ILoTWRepository
+import com.rtbishop.look4sat.core.domain.repository.LoTWResult
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import java.net.HttpURLConnection
+import java.net.SocketTimeoutException
+import java.net.URL
+import java.net.URLEncoder
+import java.io.IOException
+import javax.net.ssl.SSLException
+
+/**
+ * Fetches confirmed gridsquares directly from ARRL LoTW via the official report endpoint:
+ *   GET https://lotw.arrl.org/lotwuser/lotwreport.adi?login=<call>&password=<pwd>
+ *       &qso_query=1&qso_qsl=yes&qso_qsldetail=yes&qso_mydetail=yes&qso_qslsince=<date>
+ *
+ * Only QSL_RCVD=Y records are returned by LoTW for qso_qsl=yes, so every grid in the
+ * report is a *confirmed* grid (green on the map). GRIDSQUARE may be a 4- or 6-char
+ * value; VUCC_GRIDS ("EN52en,EN53fa") also yields 4-char fields. All values are
+ * truncated/expanded to the 4-char form used by the map overlay.
+ *
+ * ARRL rate-limits the report endpoint: one download in progress per user id, and
+ * frequent full-report pulls get refused. Failures are reported with an explicit
+ * cause (see LoTWResult) so the UI can tell the user what to do next.
+ */
+class LoTWRepository : ILoTWRepository {
+
+    override suspend fun fetchConfirmedGrids(callsign: String, password: String): LoTWResult =
+        withContext(Dispatchers.IO) {
+            fetchReportBody(callsign, password).fold(
+                onSuccess = { body -> parseBoth(body)?.let { LoTWResult.Success(it.first, it.second) }
+                    ?: LoTWResult.RateLimited },
+                onFailure = { toResult(it) }
+            )
+        }
+
+    override suspend fun fetchConfirmedGridQsos(
+        callsign: String,
+        password: String
+    ): LoTWResult = withContext(Dispatchers.IO) {
+        fetchReportBody(callsign, password).fold(
+            onSuccess = { body -> parseBoth(body)?.let { LoTWResult.Success(it.first, it.second) }
+                ?: LoTWResult.RateLimited },
+            onFailure = { toResult(it) }
+        )
+    }
+
+    internal fun toResult(e: Throwable): LoTWResult = when (e) {
+        is CredentialsException -> LoTWResult.BadCredentials
+        is RateLimitException -> LoTWResult.RateLimited
+        is TimeoutException -> LoTWResult.Timeout
+        else -> LoTWResult.NetworkError(e.message ?: e.javaClass.simpleName)
+    }
+
+    /** Single report fetch feeding both the grid set and the per-QSO detail. */
+    private fun parseBoth(body: String): Pair<Set<String>, Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>>? {
+        val grids = parseConfirmedGrids(body) ?: return null
+        val qsos = parseConfirmedGridQsos(body) ?: return null
+        return grids to qsos
+    }
+
+    private fun fetchReportBody(callsign: String, password: String): Result<String> {
+        val call = callsign.trim().uppercase()
+        val pwd = password.trim()
+        if (call.isBlank() || pwd.isBlank()) return Result.failure(IOException("empty credentials"))
+        // qso_qslsince with an early date forces a FULL confirmed-QSL report.
+        // Without it, LoTW applies a "system supplied default" since-date and
+        // only returns confirmations newer than the account's last query —
+        // subsequent syncs would return an empty/incremental report.
+        val since = "2000-01-01"
+        val query = buildString {
+            append("login=").append(URLEncoder.encode(call, "UTF-8"))
+            append("&password=").append(URLEncoder.encode(pwd, "UTF-8"))
+            append("&qso_query=1&qso_qsl=yes&qso_qsldetail=yes&qso_mydetail=yes")
+            append("&qso_qslsince=").append(URLEncoder.encode(since, "UTF-8"))
+        }
+        return try {
+            val connection = URL("$BASE_URL?$query").openConnection() as HttpURLConnection
+            // ARRL can be slow to accept connections from mobile networks
+            // (long TLS handshakes across the Pacific, occasional server-side
+            // queueing). 30s connect + 120s read gives the request enough
+            // headroom; the sync button stays disabled meanwhile so users
+            // see progress rather than a hung dialog.
+            connection.connectTimeout = 30_000
+            connection.readTimeout = 120_000
+            connection.requestMethod = "GET"
+            connection.setRequestProperty("Accept-Encoding", "gzip")
+            connection.instanceFollowRedirects = true
+            val code = connection.responseCode
+            if (code !in 200..299) {
+                connection.disconnect()
+                // Observed in the wild (CQRLOG #2422): LoTW answers a throttled
+                // report pull with HTTP 503 "Page request limit".
+                return if (code == 503 || code == 429) Result.failure(RateLimitException())
+                else Result.failure(IOException("HTTP $code"))
+            }
+            val stream = connection.inputStream
+            val body = ("gzip".equals(connection.contentEncoding, ignoreCase = true))
+                .let { gz -> if (gz) java.util.zip.GZIPInputStream(stream) else stream }
+                .bufferedReader().use { it.readText() }
+            connection.disconnect()
+            when {
+                // Login failure: HTTP 200 + HTML login page with the error text.
+                body.contains("incorrect", ignoreCase = true) &&
+                    body.contains("assword", ignoreCase = true) -> Result.failure(CredentialsException())
+                // Any other non-ADIF body: rate-limit refusal / server error page.
+                !body.contains("<eoh>", ignoreCase = true) -> Result.failure(RateLimitException())
+                else -> Result.success(body)
+            }
+        } catch (e: SocketTimeoutException) {
+            Result.failure(TimeoutException(e.message ?: "timed out"))
+        } catch (e: SSLException) {
+            Result.failure(IOException("TLS: ${e.message ?: "handshake failed"}"))
+        } catch (e: Exception) {
+            println("LoTWRepository fetch failure: $e")
+            Result.failure(IOException(e.message ?: e.javaClass.simpleName))
+        }
+    }
+
+    internal class CredentialsException : Exception("bad callsign/password")
+    internal class RateLimitException : Exception("report refused (rate limit / server error)")
+    internal class TimeoutException(message: String) : Exception(message)
+
+    internal fun parseConfirmedGridQsos(
+        body: String
+    ): Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>? {
+        if (!body.contains("<eoh>", ignoreCase = true)) return null
+        // One ADIF record = fields up to <EOR>. We buffer the fields we care
+        // about, then emit a GridQso on <EOR> when the record is a satellite
+        // QSO (PROP_MODE=SAT) carrying a grid.
+        val result = mutableMapOf<String, MutableList<com.rtbishop.look4sat.core.domain.model.GridQso>>()
+        var propMode: String? = null
+        var call = ""
+        var qsoDate = ""
+        var timeOn = ""
+        var satName = ""
+        var mode = ""
+        var bandUp = ""
+        var bandDown = ""
+        var dxcc: Int? = null
+        var country: String? = null
+        var cqz: Int? = null
+        var state: String? = null
+        val gridsInRecord = mutableListOf<String>()
+
+        fun emitRecord() {
+            if (propMode != "SAT" || gridsInRecord.isEmpty()) return
+            val epochMs = adifTimestampToEpoch(qsoDate, timeOn)
+            val qso = com.rtbishop.look4sat.core.domain.model.GridQso(
+                call = call, epochMs = epochMs, satName = satName,
+                mode = mode, bandUp = bandUp, bandDown = bandDown,
+                dxcc = dxcc, country = country, cqz = cqz, state = state
+            )
+            for (grid in gridsInRecord) {
+                result.getOrPut(grid) { mutableListOf() }.add(qso)
+            }
+        }
+
+        fun resetRecord() {
+            propMode = null; call = ""; qsoDate = ""; timeOn = ""
+            satName = ""; mode = ""; bandUp = ""; bandDown = ""
+            dxcc = null; country = null; cqz = null; state = null
+            gridsInRecord.clear()
+        }
+
+        for (raw in body.lineSequence()) {
+            val line = raw.trim()
+            when {
+                line.equals("<EOR>", ignoreCase = true) -> {
+                    emitRecord()
+                    resetRecord()
+                }
+                line.startsWith("<PROP_MODE:") ->
+                    propMode = adifValue(line).uppercase()
+                line.startsWith("<CALL:") ->
+                    call = adifValue(line).uppercase()
+                line.startsWith("<QSO_DATE:") ->
+                    qsoDate = adifValue(line)
+                line.startsWith("<TIME_ON:") ->
+                    timeOn = adifValue(line)
+                line.startsWith("<SAT_NAME:") ->
+                    satName = adifValue(line)
+                line.startsWith("<MODE:") ->
+                    mode = adifValue(line)
+                line.startsWith("<BAND_RX:") ->
+                    bandUp = adifValue(line).uppercase()
+                line.startsWith("<BAND:") && !line.startsWith("<BAND_RX:") ->
+                    bandDown = adifValue(line).uppercase()
+                line.startsWith("<DXCC:") ->
+                    dxcc = adifValue(line).toIntOrNull()
+                line.startsWith("<COUNTRY:") ->
+                    country = adifValue(line).ifBlank { null }
+                line.startsWith("<CQZ:") ->
+                    cqz = adifValue(line).toIntOrNull()
+                line.startsWith("<STATE:") ->
+                    state = adifValue(line).trim().ifBlank { null }?.let { normalizeState(it) }
+                line.startsWith("<GRIDSQUARE:") || line.startsWith("<VUCC_GRIDS:") -> {
+                    // VUCC_GRIDS holds a comma-separated list of grids
+                    // ("EN52en,EN53fa"), up to four for contacts spanning
+                    // several squares; split and keep every 4-char field.
+                    adifValue(line).split(',').forEach { grid ->
+                        val field = grid.trim().uppercase()
+                        if (field.length >= 4) gridsInRecord.add(field.take(4))
+                    }
+                }
+            }
+        }
+        return result
+    }
+
+    /** ADIF field value: "<GRIDSQUARE:4>OL62" -> "OL62". */
+    private fun adifValue(line: String): String =
+        line.substringAfter('>').substringBefore("E<").trim()
+
+    /**
+     * LoTW returns STATE as "CODE // NAME" (e.g. "HB // Hubei" for China,
+     * "34 // Tottori-ken" for Japan, "CA // California" for the US). The award
+     * statistics match on the short CODE only (China 2-letter province pinyin,
+     * Japan 2-digit prefecture, US 2-letter state), so strip the " // NAME"
+     * suffix here once, storing the clean code for every downstream consumer
+     * (persistence, AwardCalculator).
+     */
+    private fun normalizeState(raw: String): String = raw.substringBefore(" // ").trim()
+
+    /** "20260820" + "1130" (or "113000") -> UTC epoch ms; 0 when unparseable. */
+    private fun adifTimestampToEpoch(date: String, time: String): Long = try {
+        val d = date.trim()
+        val t = time.trim().padEnd(6, '0').take(6)
+        val fmt = java.time.format.DateTimeFormatterBuilder()
+            .appendPattern("yyyyMMddHHmmss")
+            .toFormatter()
+            .withZone(java.time.ZoneOffset.UTC)
+        java.time.Instant.from(fmt.parse(d + t)).toEpochMilli()
+    } catch (_: Exception) {
+        0L
+    }
+
+    internal fun parseConfirmedGrids(body: String): Set<String>? {
+        // LoTW answers with ADIF text; on bad credentials it returns a short error page
+        // containing "password=?" or an <eoh>-less block. Treat anything without a header
+        // marker as failure so the caller can show a sensible message.
+        // LoTW answers with ADIF text; on bad credentials it returns a short error
+        // page without an <eoh> header terminator. Real reports always carry <eoh>
+        // (LoTW writes it lowercase). Match case-insensitively to be safe.
+        if (!body.contains("<eoh>", ignoreCase = true)) return null
+        val grids = mutableSetOf<String>()
+        // ADIF fields of one QSO record span multiple lines and are terminated by
+        // <EOR>. Satellite QSOs carry <PROP_MODE:3>SAT (plus <SAT_NAME>); ground
+        // QSOs omit it. Grid fields (GRIDSQUARE / VUCC_GRIDS) must only be
+        // collected for records whose PROP_MODE is SAT, otherwise the map mixes
+        // in terrestrial contacts.
+        var propMode: String? = null
+        for (raw in body.lineSequence()) {
+            val line = raw.trim()
+            when {
+                line.equals("<EOR>", ignoreCase = true) -> propMode = null
+                line.startsWith("<PROP_MODE:") -> {
+                    propMode = line.substringAfter('>').substringBefore("E<").trim().uppercase()
+                }
+                line.startsWith("<GRIDSQUARE:") || line.startsWith("<VUCC_GRIDS:") -> {
+                    if (propMode == "SAT") {
+                        // VUCC_GRIDS holds a comma-separated PAIR of grids
+                        // ("EN52en,EN53fa") for contacts spanning two squares —
+                        // split on ',' and take the 4-char field of each, or the
+                        // second grid is silently dropped.
+                        val value = line.substringAfter('>').substringBefore("E<")
+                        value.split(',').forEach { grid ->
+                            val field = grid.trim().uppercase()
+                            if (field.length >= 4) grids.add(field.take(4))
+                        }
+                    }
+                }
+            }
+        }
+        return grids
+    }
+
+    private companion object {
+        const val BASE_URL = "https://lotw.arrl.org/lotwuser/lotwreport.adi"
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SatelliteRepo.kt

@@ -28,10 +28,16 @@ import com.rtbishop.look4sat.core.domain.source.ILocalSource
 import com.rtbishop.look4sat.core.domain.utility.round
 import com.rtbishop.look4sat.core.domain.utility.toDegrees
 import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.async
+import kotlinx.coroutines.awaitAll
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.withContext
+import java.util.TimeZone
 
 class SatelliteRepo(
     private val dispatcher: CoroutineDispatcher,
@@ -42,18 +48,39 @@ class SatelliteRepo(
     private val _passes = MutableStateFlow<List<OrbitalPass>>(emptyList())
     override val passes: StateFlow<List<OrbitalPass>> = _passes
 
+    private val _isCalculating = MutableStateFlow(false)
+    override val isCalculating: StateFlow<Boolean> = _isCalculating
+
     private val _satellites = MutableStateFlow<List<OrbitalObject>>(emptyList())
     override val satellites: StateFlow<List<OrbitalObject>> = _satellites
 
+    private val _selectedPass = MutableStateFlow(0 to 0L)
+    override val selectedPass: StateFlow<Pair<Int, Long>> = _selectedPass
+
+    override fun selectPass(catNum: Int, aosTime: Long) {
+        _selectedPass.value = catNum to aosTime
+    }
+
     override suspend fun getRadiosWithId(id: Int) = localStorage.getRadiosWithId(id)
 
     override suspend fun initRepository() = withContext(dispatcher) {
-        settingsRepo.selectedIds.collect { selectedIds ->
-            _satellites.update { localStorage.getEntriesWithIds(selectedIds) }
-            val (hoursAhead, minElevation, modes) = settingsRepo.passesSettings.value
-            val timeNow = 1000 * ((System.currentTimeMillis() + 500) / 1000)
-            calculatePasses(timeNow, hoursAhead, minElevation, modes)
-        }
+        combine(
+            settingsRepo.selectedIds,
+            settingsRepo.stationPosition
+        ) { selectedIds, _ -> selectedIds }
+            .collect { selectedIds ->
+                _satellites.update { localStorage.getEntriesWithIds(selectedIds) }
+                val settings = settingsRepo.passesSettings.value
+                calculatePasses(
+                    time = System.currentTimeMillis(),
+                    hoursAhead = settings.hoursAhead,
+                    minElevation = settings.minElevation,
+                    aosStartMinute = settings.aosStartMinute,
+                    aosEndMinute = settings.aosEndMinute,
+                    invertAosTimeWindow = settings.invertAosTimeWindow,
+                    modes = settings.selectedModes
+                )
+            }
     }
 
     override suspend fun getPosition(sat: OrbitalObject, pos: GeoPos, time: Long): OrbitalPos {
@@ -62,7 +89,8 @@ class SatelliteRepo(
 
     override suspend fun getTrack(sat: OrbitalObject, pos: GeoPos, start: Long, end: Long): List<OrbitalPos> {
         return withContext(dispatcher) {
-            val positions = mutableListOf<OrbitalPos>()
+            val estimatedSize = ((end - start) / 15000).toInt() + 1
+            val positions = ArrayList<OrbitalPos>(estimatedSize)
             var currentTime = start
             while (currentTime < end) {
                 positions.add(sat.getPosition(pos, currentTime))
@@ -80,65 +108,100 @@ class SatelliteRepo(
     ): List<SatRadio> {
         return withContext(dispatcher) {
             val satPos = sat.getPosition(pos, time)
-            val copiedList = radios.map { it.copy() }
-            copiedList.forEach { transmitter ->
-                transmitter.downlinkLow?.let { transmitter.downlinkLow = satPos.getDownlinkFreq(it) }
-                transmitter.downlinkHigh?.let { transmitter.downlinkHigh = satPos.getDownlinkFreq(it) }
-                transmitter.uplinkLow?.let { transmitter.uplinkLow = satPos.getUplinkFreq(it) }
-                transmitter.uplinkHigh?.let { transmitter.uplinkHigh = satPos.getUplinkFreq(it) }
+            radios.map { transmitter ->
+                transmitter.copy(
+                    downlinkLow = transmitter.downlinkLow?.let { satPos.getDownlinkFreq(it) },
+                    downlinkHigh = transmitter.downlinkHigh?.let { satPos.getDownlinkFreq(it) },
+                    uplinkLow = transmitter.uplinkLow?.let { satPos.getUplinkFreq(it) },
+                    uplinkHigh = transmitter.uplinkHigh?.let { satPos.getUplinkFreq(it) }
+                )
             }
-            copiedList.map { it.copy() }
         }
     }
 
-    override suspend fun processPasses(passList: List<OrbitalPass>, time: Long): List<OrbitalPass> {
-        return withContext(dispatcher) {
-            passList.forEach { pass ->
-                if (!pass.isDeepSpace) {
-                    val timeStart = pass.aosTime
-                    if (time > timeStart) {
-                        val deltaNow = time.minus(timeStart).toFloat()
-                        val deltaTotal = pass.losTime.minus(timeStart).toFloat()
-                        pass.progress = (deltaNow / deltaTotal).round(2)
+    override suspend fun calculatePasses(
+        time: Long,
+        hoursAhead: Int,
+        minElevation: Double,
+        aosStartMinute: Int,
+        aosEndMinute: Int,
+        invertAosTimeWindow: Boolean,
+        modes: List<String>
+    ) {
+        _isCalculating.value = true
+        // Normalize to the start of the current minute so that coarse 60-second stepping
+        // in getLeoPass always begins from the same phase, producing stable AOS/LOS times
+        val normalizedTime = time / 60_000L * 60_000L
+        val currentSatellites = _satellites.value
+        withContext(dispatcher) {
+            val idsWithModes = localStorage.getIdsWithModes(modes)
+            val stationPos = settingsRepo.stationPosition.value
+            val filteredSatellites = if (idsWithModes.isEmpty()) {
+                currentSatellites
+            } else {
+                currentSatellites.filter { it.data.catnum in idsWithModes }
+            }
+            // Compute passes for each satellite in parallel
+            val passLists = coroutineScope {
+                filteredSatellites.map { satellite ->
+                    async { satellite.getPasses(stationPos, normalizedTime, hoursAhead) }
+                }.awaitAll()
+            }
+            // Flatten and filter in a single pass
+            val timeFuture = normalizedTime + (hoursAhead * 60L * 60L * 1000L)
+            val newPasses = ArrayList<OrbitalPass>()
+            for (list in passLists) {
+                for (pass in list) {
+                    if (
+                        pass.losTime > time
+                        && pass.aosTime < timeFuture
+                        && pass.maxElevation > minElevation
+                        && (pass.isDeepSpace || isAosInRange(pass.aosTime, aosStartMinute, aosEndMinute, invertAosTimeWindow))
+                    ) {
+                        newPasses.add(pass)
                     }
                 }
             }
-            passList.filter { pass -> pass.progress < 1.0 }.map { it.copy() }
+            newPasses.sortBy { it.aosTime }
+            delay(1000) // Simulate loading time for better UX
+            _passes.update { newPasses }
         }
+        _isCalculating.value = false
     }
 
-    override suspend fun calculatePasses(time: Long, hoursAhead: Int, minElevation: Double, modes: List<String>) {
-        if (_satellites.value.isNotEmpty()) {
-            withContext(dispatcher) {
-                val newPasses = mutableListOf<OrbitalPass>()
-                val idsWithModes = localStorage.getIdsWithModes(modes)
-                _satellites.value.forEach { satellite ->
-                    if (idsWithModes.isEmpty() || satellite.data.catnum in idsWithModes) {
-                        newPasses.addAll(satellite.getPasses(settingsRepo.stationPosition.value, time, hoursAhead))
-                    }
-                }
-                _passes.update { newPasses.filter(time, hoursAhead, minElevation) }
-            }
+    private fun isAosInRange(
+        aosTime: Long,
+        aosStartMinute: Int,
+        aosEndMinute: Int,
+        invertAosTimeWindow: Boolean
+    ): Boolean {
+        val offsetMillis = TimeZone.getDefault().getOffset(aosTime).toLong()
+        val localMillis = Math.floorMod(aosTime + offsetMillis, 24L * 60L * 60L * 1000L)
+        val aosMinute = (localMillis / 60_000L).toInt()
+        val inRange = if (aosStartMinute <= aosEndMinute) {
+            aosMinute in aosStartMinute..aosEndMinute
         } else {
-            _passes.update { emptyList() }
+            aosMinute >= aosStartMinute || aosMinute <= aosEndMinute
         }
+        return if (invertAosTimeWindow) !inRange else inRange
     }
 
     private fun OrbitalObject.getPasses(pos: GeoPos, time: Long, hours: Int): List<OrbitalPass> {
         val passes = mutableListOf<OrbitalPass>()
         val endDate = time + hours * 60L * 60L * 1000L
         val quarterOrbitMin = (this.data.orbitalPeriod / 4.0).toInt()
+        val decayed = this.data.hasDecayed(time)
         var startDate = time
         var shouldRewind = true
         var lastAosDate: Long
         var count = 0
         if (this.willBeSeen(pos)) {
             if (this.data.isDeepSpace) {
-                passes.add(getGeoPass(this, pos, time))
+                passes.add(getGeoPass(this, pos, time, decayed))
             } else {
                 do {
                     if (count > 0) shouldRewind = false
-                    val pass = getLeoPass(this, pos, startDate, shouldRewind)
+                    val pass = getLeoPass(this, pos, startDate, shouldRewind, decayed)
                     lastAosDate = pass.aosTime
                     passes.add(pass)
                     startDate = pass.losTime + (quarterOrbitMin * 3) * 60L * 1000L
@@ -149,94 +212,80 @@ class SatelliteRepo(
         return passes
     }
 
-    private fun List<OrbitalPass>.filter(time: Long, hoursAhead: Int, minElev: Double): List<OrbitalPass> {
-        val timeFuture = time + (hoursAhead * 60L * 60L * 1000L)
-        return this.filter { it.losTime > time }.filter { it.aosTime < timeFuture }
-            .filter { it.maxElevation > minElev }.sortedBy { it.aosTime }
-    }
-
-    private fun getGeoPass(sat: OrbitalObject, pos: GeoPos, time: Long): OrbitalPass {
+    private fun getGeoPass(sat: OrbitalObject, pos: GeoPos, time: Long, decayed: Boolean): OrbitalPass {
         val satPos = sat.getPosition(pos, time)
         val aos = time - 24 * 60L * 60L * 1000L
         val los = time + 24 * 60L * 60L * 1000L // val tca = (aos + los) / 2
         val az = satPos.azimuth.toDegrees().round(1)
         val elev = satPos.elevation.toDegrees().round(1)
         val alt = satPos.altitude
-        return OrbitalPass(aos, az, los, az, alt.toInt(), elev, sat)
+        return OrbitalPass(aos, az, los, az, alt.toInt(), elev, sat, hasDecayed = decayed)
     }
 
-    private fun getLeoPass(sat: OrbitalObject, pos: GeoPos, time: Long, rewind: Boolean): OrbitalPass {
+    private fun getLeoPass(sat: OrbitalObject, pos: GeoPos, time: Long, rewind: Boolean, decayed: Boolean): OrbitalPass {
         val quarterOrbitMin = (sat.data.orbitalPeriod / 4.0).toInt()
         var calendarTimeMillis = time
         var elevation: Double
         var maxElevation = 0.0
-        var alt = 0.0 // var tcaAz = 0.0
         // rewind 1/4 of an orbit
-        if (rewind) calendarTimeMillis += -quarterOrbitMin * 60L * 1000L
+        if (rewind) calendarTimeMillis -= quarterOrbitMin * 60L * 1000L
 
-        var satPos = sat.getPosition(pos, calendarTimeMillis)
-        if (satPos.elevation > 0.0) {
+        // Use lightweight elevation check for coarse searching
+        if (sat.getElevation(pos, calendarTimeMillis) > 0.0) {
             // move forward in 30 second intervals until the sat goes below the horizon
             do {
                 calendarTimeMillis += 30 * 1000L
-                satPos = sat.getPosition(pos, calendarTimeMillis)
-            } while (satPos.elevation > 0.0)
+            } while (sat.getElevation(pos, calendarTimeMillis) > 0.0)
             // move forward 3/4 of an orbit
             calendarTimeMillis += quarterOrbitMin * 3 * 60L * 1000L
         }
 
-        // find the next time sat comes above the horizon
+        // find the next time sat comes above the horizon (coarse: 60s steps)
         do {
             calendarTimeMillis += 60L * 1000L
-            satPos = sat.getPosition(pos, calendarTimeMillis)
-            elevation = satPos.elevation
-            if (elevation > maxElevation) {
-                maxElevation = elevation
-                alt = satPos.altitude // tcaAz = satPos.azimuth.toDegrees()
-            }
-        } while (satPos.elevation < 0.0)
+            elevation = sat.getElevation(pos, calendarTimeMillis)
+            if (elevation > maxElevation) maxElevation = elevation
+        } while (elevation < 0.0)
 
-        // refine to 1 second
-        calendarTimeMillis += -60L * 1000L
+        // refine AOS to ~500ms precision
+        calendarTimeMillis -= 60L * 1000L
         do {
-            calendarTimeMillis += 1L * 500L
-            satPos = sat.getPosition(pos, calendarTimeMillis)
-            elevation = satPos.elevation
-            if (elevation > maxElevation) {
-                maxElevation = elevation
-                alt = satPos.altitude // tcaAz = satPos.azimuth.toDegrees()
-            }
-        } while (satPos.elevation < 0.0)
+            calendarTimeMillis += 500L
+            elevation = sat.getElevation(pos, calendarTimeMillis)
+            if (elevation > maxElevation) maxElevation = elevation
+        } while (elevation < 0.0)
 
-        val aos = 1000 * ((satPos.time + 500) / 1000)
-        val aosAz = satPos.azimuth.toDegrees().round(1)
+        // Get full position for AOS data (azimuth, altitude)
+        val aosPos = sat.getFullPosition(pos, calendarTimeMillis)
+        val aos = 1000 * ((aosPos.time + 500) / 1000)
+        val aosAz = aosPos.azimuth.toDegrees().round(1)
 
-        // find when sat goes below
+        // find when sat goes below (coarse: 30s steps)
         do {
             calendarTimeMillis += 30L * 1000L
-            satPos = sat.getPosition(pos, calendarTimeMillis)
-            elevation = satPos.elevation
-            if (elevation > maxElevation) {
-                maxElevation = elevation
-                alt = satPos.altitude // tcaAz = satPos.azimuth.toDegrees()
-            }
-        } while (satPos.elevation > 0.0)
+            elevation = sat.getElevation(pos, calendarTimeMillis)
+            if (elevation > maxElevation) maxElevation = elevation
+        } while (elevation > 0.0)
 
-        // refine to 1 second
-        calendarTimeMillis += -30L * 1000L
+        // refine LOS to ~500ms precision
+        calendarTimeMillis -= 30L * 1000L
         do {
-            calendarTimeMillis += 1L * 500L
-            satPos = sat.getPosition(pos, calendarTimeMillis)
-            elevation = satPos.elevation
-            if (elevation > maxElevation) {
-                maxElevation = elevation
-                alt = satPos.altitude // tcaAz = satPos.azimuth.toDegrees()
-            }
-        } while (satPos.elevation > 0.0)
+            calendarTimeMillis += 500L
+            elevation = sat.getElevation(pos, calendarTimeMillis)
+            if (elevation > maxElevation) maxElevation = elevation
+        } while (elevation > 0.0)
+
+        // Get full position for LOS data (azimuth, altitude)
+        val losPos = sat.getFullPosition(pos, calendarTimeMillis)
+        val los = 1000 * ((losPos.time + 500) / 1000)
+        val losAz = losPos.azimuth.toDegrees().round(1)
+
+        // Get altitude at approximate TCA (max elevation)
+        val tcaTime = (aos + los) / 2
+        val tcaPos = sat.getFullPosition(pos, tcaTime)
+        val alt = tcaPos.altitude
 
-        val los = 1000 * ((satPos.time + 500) / 1000) // val tca = (aos + los) / 2
-        val losAz = satPos.azimuth.toDegrees().round(1)
         val elev = maxElevation.toDegrees().round(1)
-        return OrbitalPass(aos, aosAz, los, losAz, alt.toInt(), elev, sat)
+        return OrbitalPass(aos, aosAz, los, losAz, alt.toInt(), elev, sat, hasDecayed = decayed)
     }
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SelectionRepo.kt

@@ -40,11 +40,23 @@ class SelectionRepo(
     private val currentItems = MutableStateFlow<List<SatItem>>(emptyList())
     private val currentTypes = MutableStateFlow(settingsRepo.selectedTypes.value)
     private val currentQuery = MutableStateFlow("")
+
+    // Resolve type IDs once when types change, then filter items reactively.
+    // The HashSet gives O(1) catnum lookups instead of O(n) with a List.
     private val itemsWithTypes = currentTypes.flatMapLatest { types: List<String> ->
-        currentItems.map { items -> items.filterByTypes(types) }
+        val catnumSet: Set<Int>? = if (types.isEmpty()) {
+            null // null = no filtering
+        } else {
+            val ids = settingsRepo.getSatelliteTypesIds(types)
+            if (ids.isEmpty()) null else ids.toHashSet()
+        }
+        currentItems.map { items ->
+            if (catnumSet == null) items else items.filter { it.catnum in catnumSet }
+        }
     }
+
     private val itemsWithQuery = currentQuery.flatMapLatest { query ->
-        itemsWithTypes.map { items -> items.filterByQuery(query) }
+        itemsWithTypes.map { items -> filterByQuery(items, query) }
     }
 
     override fun getCurrentTypes() = currentTypes.value
@@ -54,7 +66,7 @@ class SelectionRepo(
     }
 
     override suspend fun getEntriesFlow() = withContext(dispatcher) {
-        val selectedIds = settingsRepo.selectedIds.value
+        val selectedIds = settingsRepo.selectedIds.value.toHashSet()
         currentItems.value = localSource.getEntriesList().map { item ->
             item.copy(isSelected = item.catnum in selectedIds)
         }
@@ -66,17 +78,19 @@ class SelectionRepo(
         settingsRepo.setSelectedTypes(types)
     }
 
-    override suspend fun setQuery(query: String) = withContext(dispatcher) {
+    override suspend fun setQuery(query: String) {
         currentQuery.value = query
     }
 
     override suspend fun setSelection(selectAll: Boolean) = withContext(dispatcher) {
-        setSelection(itemsWithQuery.first().map { item -> item.catnum }, selectAll)
+        val visibleIds = itemsWithQuery.first().mapTo(HashSet()) { it.catnum }
+        setSelection(visibleIds, selectAll)
     }
 
     override suspend fun setSelection(ids: List<Int>, isTicked: Boolean) = withContext(dispatcher) {
+        val idSet = ids.toHashSet()
         currentItems.value = currentItems.value.map { item ->
-            if (item.catnum in ids) item.copy(isSelected = isTicked) else item
+            if (item.catnum in idSet) item.copy(isSelected = isTicked) else item
         }
     }
 
@@ -85,19 +99,24 @@ class SelectionRepo(
         settingsRepo.setSelectedIds(currentSelection)
     }
 
-    private suspend fun List<SatItem>.filterByTypes(types: List<String>) = withContext(dispatcher) {
-        if (types.isEmpty()) return@withContext this@filterByTypes
-        val catnums = settingsRepo.getSatelliteTypesIds(types)
-        if (catnums.isEmpty()) return@withContext this@filterByTypes
-        return@withContext this@filterByTypes.filter { item -> item.catnum in catnums }
-    }
-
-    private suspend fun List<SatItem>.filterByQuery(query: String) = withContext(dispatcher) {
-        if (query.isBlank()) return@withContext this@filterByQuery
-        return@withContext try {
-            this@filterByQuery.filter { it.catnum == query.toInt() }
-        } catch (_: Exception) {
-            this@filterByQuery.filter { item -> item.name.lowercase().contains(query.lowercase()) }
+    /**
+     * Bulk selection using a pre-built Set for O(1) lookups.
+     */
+    private suspend fun setSelection(idSet: Set<Int>, isTicked: Boolean) = withContext(dispatcher) {
+        currentItems.value = currentItems.value.map { item ->
+            if (item.catnum in idSet) item.copy(isSelected = isTicked) else item
         }
     }
+
+    /**
+     * Filters items by query. Uses toIntOrNull() instead of exception-based flow,
+     * and lowercases the query once up front instead of per-item.
+     */
+    private fun filterByQuery(items: List<SatItem>, query: String): List<SatItem> {
+        if (query.isBlank()) return items
+        val catnum = query.toIntOrNull()
+        if (catnum != null) return items.filter { it.catnum == catnum }
+        val lowerQuery = query.lowercase()
+        return items.filter { it.name.lowercase().contains(lowerQuery) }
+    }
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SensorsRepo.kt

@@ -22,8 +22,9 @@ import android.hardware.Sensor
 import android.hardware.SensorEvent
 import android.hardware.SensorEventListener
 import android.hardware.SensorManager
+import android.hardware.display.DisplayManager
+import android.view.Display
 import android.view.Surface
-import android.view.WindowManager
 import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import com.rtbishop.look4sat.core.domain.predict.RAD2DEG
 import com.rtbishop.look4sat.core.domain.repository.ISensorsRepo
@@ -31,82 +32,101 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlin.math.round
 
+private const val SMOOTHING_FACTOR = 0.15f
+private const val SENSOR_RATE_US = 16_000
+
 class SensorsRepo(
     private val sensorManager: SensorManager,
-    private val sensor: Sensor?,
-    private val windowManager: WindowManager
-) :
-    SensorEventListener, ISensorsRepo {
+    private val displayManager: DisplayManager?
+) : ISensorsRepo, SensorEventListener {
 
-    private val _orientation = MutableStateFlow(Pair(0f, 0f))
+    private val _sensorData = MutableStateFlow(Pair(0f, 0f))
+    private val sensor: Sensor? = sensorManager.getDefaultSensor(Sensor.TYPE_ROTATION_VECTOR)
     private val rotationMatrix = FloatArray(9)
+    private val tempMatrix = FloatArray(9)
     private val orientationValues = FloatArray(3)
-    private var sensorAccuracy = SensorManager.SENSOR_STATUS_UNRELIABLE
+    private var smoothAzimuth = 0f
+    private var smoothPitch = 0f
+    private var hasInitialReading = false
 
-    override val orientation: StateFlow<Pair<Float, Float>> = _orientation
+    override val sensorData: StateFlow<Pair<Float, Float>> = _sensorData
 
     override fun getMagDeclination(geoPos: GeoPos, time: Long): Float {
-        val latitude = geoPos.latitude.toFloat()
-        val longitude = geoPos.longitude.toFloat()
-        return GeomagneticField(latitude, longitude, geoPos.altitude.toFloat(), time).declination
+        return GeomagneticField(
+            geoPos.latitude.toFloat(),
+            geoPos.longitude.toFloat(),
+            geoPos.altitude.toFloat(),
+            time
+        ).declination
     }
 
     override fun enableSensor() {
-        sensor?.let { sensorManager.registerListener(this, it, 8000) }
+        hasInitialReading = false
+        sensor?.let { sensorManager.registerListener(this, it, SENSOR_RATE_US) }
     }
 
     override fun disableSensor() = sensorManager.unregisterListener(this)
 
-    override fun onAccuracyChanged(sensor: Sensor, accuracy: Int) {
-        sensorAccuracy = accuracy
-    }
+    override fun onAccuracyChanged(sensor: Sensor, accuracy: Int) = Unit
 
-    override fun onSensorChanged(event: SensorEvent) = when {
-        sensorAccuracy == SensorManager.SENSOR_STATUS_UNRELIABLE -> {}
-        event.sensor == sensor -> updateOrientation(event.values)
-        else -> {}
+    override fun onSensorChanged(event: SensorEvent) {
+        if (event.sensor.type == Sensor.TYPE_ROTATION_VECTOR) handleSensorEvent(event)
     }
 
     private fun getDisplayRotation(): Int {
-        return try {
-            @Suppress("DEPRECATION")
-            windowManager.defaultDisplay.rotation
-        } catch (e: Exception) {
-            Surface.ROTATION_0
-        }
+        return displayManager?.getDisplay(Display.DEFAULT_DISPLAY)?.rotation ?: Surface.ROTATION_0
     }
 
-    private fun transformRotationMatrix(rotationMatrix: FloatArray, rotation: Int) {
-        val tempMatrix = FloatArray(9)
-        when (rotation) {
-            Surface.ROTATION_0 -> {
-                SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_X, SensorManager.AXIS_Y, tempMatrix)
-                System.arraycopy(tempMatrix, 0, rotationMatrix, 0, 9)
-            }
-            Surface.ROTATION_90 -> {
-                SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_Y, SensorManager.AXIS_MINUS_X, tempMatrix)
-                SensorManager.remapCoordinateSystem(tempMatrix, SensorManager.AXIS_MINUS_X, SensorManager.AXIS_Y, rotationMatrix)
-            }
-            Surface.ROTATION_180 -> {
-                SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_MINUS_X, SensorManager.AXIS_MINUS_Y, tempMatrix)
-                System.arraycopy(tempMatrix, 0, rotationMatrix, 0, 9)
-            }
-            Surface.ROTATION_270 -> {
-                SensorManager.remapCoordinateSystem(rotationMatrix, SensorManager.AXIS_MINUS_Y, SensorManager.AXIS_X, tempMatrix)
-                SensorManager.remapCoordinateSystem(tempMatrix, SensorManager.AXIS_MINUS_X, SensorManager.AXIS_Y, rotationMatrix)
-            }
+    private fun remapForRotation(rotation: Int) {
+        val remapped = when (rotation) {
+            Surface.ROTATION_90 -> SensorManager.remapCoordinateSystem(
+                rotationMatrix, SensorManager.AXIS_Y, SensorManager.AXIS_MINUS_X, tempMatrix
+            )
+
+            Surface.ROTATION_180 -> SensorManager.remapCoordinateSystem(
+                rotationMatrix, SensorManager.AXIS_MINUS_X, SensorManager.AXIS_MINUS_Y, tempMatrix
+            )
+
+            Surface.ROTATION_270 -> SensorManager.remapCoordinateSystem(
+                rotationMatrix, SensorManager.AXIS_MINUS_Y, SensorManager.AXIS_X, tempMatrix
+            )
+
+            else -> false
         }
+        if (remapped) System.arraycopy(tempMatrix, 0, rotationMatrix, 0, 9)
     }
 
-    private fun updateOrientation(rotationVector: FloatArray) {
-        SensorManager.getRotationMatrixFromVector(rotationMatrix, rotationVector)
-        transformRotationMatrix(rotationMatrix, getDisplayRotation())
+    private fun handleSensorEvent(event: SensorEvent) {
+        SensorManager.getRotationMatrixFromVector(rotationMatrix, event.values)
+        remapForRotation(getDisplayRotation())
         SensorManager.getOrientation(rotationMatrix, orientationValues)
-        val azimuth = (orientationValues[0] * RAD2DEG).toFloat()
-        val pitch = (orientationValues[1] * RAD2DEG).toFloat() // roll [2]
-        val magneticAzimuth = (azimuth + 360f) % 360f
-        val roundedAzimuth = round(magneticAzimuth * 10) / 10
-        val roundedPitch = round(pitch * 10) / 10
-        _orientation.value = Pair(roundedAzimuth, roundedPitch)
+        val azimuth = normalizeAzimuth((orientationValues[0] * RAD2DEG).toFloat())
+        val pitch = (orientationValues[1] * RAD2DEG).toFloat()
+        if (!hasInitialReading) {
+            smoothAzimuth = azimuth
+            smoothPitch = pitch
+            hasInitialReading = true
+        } else {
+            smoothAzimuth = lowPassAngle(smoothAzimuth, azimuth)
+            smoothPitch = lowPass(smoothPitch, pitch)
+        }
+        _sensorData.value = Pair(round(smoothAzimuth * 10) / 10, round(smoothPitch * 10) / 10)
     }
+
+    private fun lowPass(previous: Float, current: Float): Float {
+        return previous + SMOOTHING_FACTOR * (current - previous)
+    }
+
+    /**
+     * Low-pass filter that accounts for the 0°/360° wraparound.
+     * Always takes the shortest angular path between the two values.
+     */
+    private fun lowPassAngle(previous: Float, current: Float): Float {
+        var delta = current - previous
+        while (delta > 180f) delta -= 360f
+        while (delta <= -180f) delta += 360f
+        return normalizeAzimuth(previous + SMOOTHING_FACTOR * delta)
+    }
+
+    private fun normalizeAzimuth(value: Float): Float = (value + 360f) % 360f
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SettingsRepo.kt

@@ -28,6 +28,8 @@ import com.rtbishop.look4sat.core.domain.model.DatabaseState
 import com.rtbishop.look4sat.core.domain.model.OtherSettings
 import com.rtbishop.look4sat.core.domain.model.PassesSettings
 import com.rtbishop.look4sat.core.domain.model.RCSettings
+import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
+import com.rtbishop.look4sat.core.domain.model.WavelogSettings
 import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import com.rtbishop.look4sat.core.domain.repository.ISettingsRepo
 import com.rtbishop.look4sat.core.domain.utility.positionToQth
@@ -36,6 +38,10 @@ import com.rtbishop.look4sat.core.domain.utility.round
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.update
+import org.json.JSONObject
+import java.util.Locale
+import com.rtbishop.look4sat.core.domain.model.Constants
+import com.rtbishop.look4sat.core.domain.source.Sources
 
 class SettingsRepo(
     private val locationManager: LocationManager,
@@ -50,8 +56,12 @@ class SettingsRepo(
     private val keyBluetoothFrequencyState = "bluetoothFrequencyState"
     private val keyBluetoothFrequencyAddress = "bluetoothFrequencyAddress"
     private val keyBluetoothFrequencyFormat = "bluetoothFrequencyFormat"
+    private val keyFilterShowDeepSpace = "filterShowDeepSpace"
     private val keyFilterHoursAhead = "filterHoursAhead"
     private val keyFilterMinElevation = "filterMinElevation"
+    private val keyFilterAosStartMinute = "filterAosStartMinute"
+    private val keyFilterAosEndMinute = "filterAosEndMinute"
+    private val keyFilterAosInvert = "filterAosInvert"
     private val keyNumberOfRadios = "numberOfRadios"
     private val keyNumberOfSatellites = "numberOfSatellites"
     private val keyRotatorAddress = "rotatorAddress"
@@ -62,6 +72,7 @@ class SettingsRepo(
     private val keyFrequencyAddress = "frequencyAddress"
     private val keyFrequencyPort = "frequencyPort"
     private val keyFrequencyFormat = "frequencyFormat"
+    private val keyFrequencyOffsetHz = "frequencyOffsetHz"
     private val keySelectedIds = "selectedIds"
     private val keySelectedTypes = "selectedTypes"
     private val keySelectedModes = "selectedModes"
@@ -70,6 +81,8 @@ class SettingsRepo(
     private val keyStateOfSweep = "stateOfSweep"
     private val keyStateOfUtc = "stateOfUtc"
     private val keyStateOfLightTheme = "stateOfLightTheme"
+    private val keyStateOfNightMode = "stateOfNightMode"
+    private val keyStateOfMapGrid = "stateOfMapGrid"
     private val keyStationAltitude = "stationAltitude"
     private val keyStationLatitude = "stationLatitude"
     private val keyStationLongitude = "stationLongitude"
@@ -78,11 +91,22 @@ class SettingsRepo(
     private val keyUpdateTimestamp = "updateTimestamp"
     private val keyShouldSeeWarning = "shouldSeeWarning"
     private val keyShouldSeeWhatsNew = "shouldSeeWhatsNew_v$appVersionName"
+    private val keySstvMode = "sstvMode"
+    private val keyLowElevation = "lowElevation"
+    private val keyHighElevation = "highElevation"
     private val keyUseCustomTle = "useCustomTle"
     private val keyUseCustomTransceivers = "useCustomTransceivers"
     private val keyTleUrl = "tleUrl"
     private val keyTransceiversUrl = "transceiversUrl"
+    private val keySatelliteUrls = "satelliteUrls"
+    private val keyTransceiversUrls = "transceiversUrls"
+    private val keySatelliteEnabled = "satelliteEnabled"
+    private val keyTransceiversEnabled = "transceiversEnabled"
+    private val keySatnogsTleSourceMigration = "satnogsTleSourceMigration"
     private val separatorComma = ","
+    private val separatorUrl = "\n"
+    private val legacyCelestrakSatnogsUrl =
+        "https://celestrak.org/NORAD/elements/gp.php?GROUP=satnogs&FORMAT=csv"
 
     //region # Satellites selection settings
     private val _satelliteSelection = MutableStateFlow(getSelectedIds())
@@ -109,29 +133,171 @@ class SettingsRepo(
     }
 
     private fun getSelectedTypes(): List<String> {
-        val typesString = preferences.getString(keySelectedTypes, null)
-        if (typesString.isNullOrEmpty()) return listOf("Amateur")
+        val typesString = preferences.getString(keySelectedTypes, "Amateur")
+        if (typesString.isNullOrEmpty()) return emptyList()
         return typesString.split(separatorComma)
     }
     //endregion
 
-    //region # Passes filter settings
+    //region # Wavelog worked-grids settings
+    private val keyWavelogUrl = "wavelogUrl"
+    private val keyWavelogToken = "wavelogToken"
+    private val keyWorkedGrids = "workedGrids"
+
+    private val _wavelogSettings = MutableStateFlow(getWavelogSettings())
+    override val wavelogSettings: StateFlow<WavelogSettings> = _wavelogSettings
+
+    override fun updateWavelogSettings(settings: WavelogSettings) {
+        preferences.edit {
+            putString(keyWavelogUrl, settings.url.trim())
+            putString(keyWavelogToken, settings.token.trim())
+        }
+        _wavelogSettings.value = settings.copy(url = settings.url.trim(), token = settings.token.trim())
+    }
+
+    private fun getWavelogSettings(): WavelogSettings = WavelogSettings(
+        url = preferences.getString(keyWavelogUrl, null).orEmpty(),
+        token = preferences.getString(keyWavelogToken, null).orEmpty()
+    )
+
+    override fun getWorkedGrids(): Set<String> {
+        val json = preferences.getString(keyWorkedGrids, null).orEmpty()
+        if (json.isBlank()) return emptySet()
+        return try {
+            val array = org.json.JSONArray(json)
+            (0 until array.length()).mapNotNull { i ->
+                array.optString(i).takeIf { it.isNotBlank() }
+            }.toSet()
+        } catch (_: Exception) {
+            emptySet()
+        }
+    }
+
+    override fun setWorkedGrids(grids: Set<String>) {
+        val array = org.json.JSONArray()
+        grids.sorted().forEach { array.put(it) }
+        preferences.edit { putString(keyWorkedGrids, array.toString()) }
+    }
+
+    // Confirmed satellite QSOs per worked gridsquare, persisted as a single JSON
+    // object: {"OL62":[{"c":call,"t":epochMs,"s":sat,"m":mode,"bu":up,"bd":down}]}.
+    private val keyWorkedGridQsos = "workedGridQsos"
+
+    override fun getWorkedGridQsos(): Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>> {
+        val json = preferences.getString(keyWorkedGridQsos, null).orEmpty()
+        if (json.isBlank()) return emptyMap()
+        return try {
+            val root = org.json.JSONObject(json)
+            val result = mutableMapOf<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>()
+            for (grid in root.keys()) {
+                val array = root.optJSONArray(grid) ?: continue
+                val list = (0 until array.length()).mapNotNull { i ->
+                    val o = array.optJSONObject(i) ?: return@mapNotNull null
+                    com.rtbishop.look4sat.core.domain.model.GridQso(
+                        call = o.optString("c"),
+                        epochMs = o.optLong("t"),
+                        satName = o.optString("s"),
+                        mode = o.optString("m"),
+                        bandUp = o.optString("bu"),
+                        bandDown = o.optString("bd"),
+                        // New award fields: absent in pre-award data -> null.
+                        dxcc = o.optInt("dx", 0).takeIf { it > 0 },
+                        country = o.optString("cty").ifBlank { null },
+                        cqz = o.optInt("cq", 0).takeIf { it > 0 },
+                        state = o.optString("st").ifBlank { null }
+                    )
+                }
+                if (list.isNotEmpty()) result[grid] = list
+            }
+            result
+        } catch (_: Exception) {
+            emptyMap()
+        }
+    }
+
+    override fun setWorkedGridQsos(qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>) {
+        val root = org.json.JSONObject()
+        for ((grid, list) in qsos) {
+            val array = org.json.JSONArray()
+            for (q in list) {
+                array.put(
+                    org.json.JSONObject()
+                        .put("c", q.call)
+                        .put("t", q.epochMs)
+                        .put("s", q.satName)
+                        .put("m", q.mode)
+                        .put("bu", q.bandUp)
+                        .put("bd", q.bandDown)
+                        .put("dx", q.dxcc ?: 0)
+                        .put("cty", q.country ?: "")
+                        .put("cq", q.cqz ?: 0)
+                        .put("st", q.state ?: "")
+                )
+            }
+            root.put(grid, array)
+        }
+        preferences.edit { putString(keyWorkedGridQsos, root.toString()) }
+    }
+
+    // LoTW credentials (stored locally on the device only)
+    private val keyLoTWCall = "lotwCallsign"
+    private val keyLoTWPass = "lotwPassword"
+
+    override val lotwSettings: kotlinx.coroutines.flow.StateFlow<com.rtbishop.look4sat.core.domain.model.LoTWSettings>
+        get() = _lotwSettings
+    private val _lotwSettings = MutableStateFlow(getLoTWSettings())
+
+    override fun updateLoTWSettings(settings: com.rtbishop.look4sat.core.domain.model.LoTWSettings) {
+        preferences.edit {
+            putString(keyLoTWCall, settings.callsign.trim().uppercase())
+            putString(keyLoTWPass, settings.password)
+        }
+        _lotwSettings.value = settings.copy(
+            callsign = settings.callsign.trim().uppercase(),
+            password = settings.password
+        )
+    }
+
+    private fun getLoTWSettings(): com.rtbishop.look4sat.core.domain.model.LoTWSettings =
+        com.rtbishop.look4sat.core.domain.model.LoTWSettings(
+            callsign = preferences.getString(keyLoTWCall, null).orEmpty(),
+            password = preferences.getString(keyLoTWPass, null).orEmpty()
+        )
+    //endregion
+
+    //region # Transceivers settings
     private val _passesSettings = MutableStateFlow(getPassesSettings())
     override val passesSettings: StateFlow<PassesSettings> = _passesSettings
 
     override fun setPassesSettings(settings: PassesSettings) = preferences.edit {
+        putBoolean(keyFilterShowDeepSpace, settings.showDeepSpace)
         putInt(keyFilterHoursAhead, settings.hoursAhead)
         putLong(keyFilterMinElevation, settings.minElevation.toRawBits())
+        putInt(keyFilterAosStartMinute, settings.aosStartMinute)
+        putInt(keyFilterAosEndMinute, settings.aosEndMinute)
+        putBoolean(keyFilterAosInvert, settings.invertAosTimeWindow)
         putString(keySelectedModes, settings.selectedModes.joinToString(separatorComma))
         _passesSettings.value = settings
     }
 
     private fun getPassesSettings(): PassesSettings {
+        val showDeepSpace = preferences.getBoolean(keyFilterShowDeepSpace, true)
         val hoursAhead = preferences.getInt(keyFilterHoursAhead, 24)
         val minElevation = Double.fromBits(preferences.getLong(keyFilterMinElevation, 16.0.toRawBits()))
+        val aosStartMinute = preferences.getInt(keyFilterAosStartMinute, 0).coerceIn(0, 23 * 60 + 59)
+        val aosEndMinute = preferences.getInt(keyFilterAosEndMinute, 23 * 60 + 59).coerceIn(0, 23 * 60 + 59)
+        val invertAosTimeWindow = preferences.getBoolean(keyFilterAosInvert, false)
         val selectedModesString = preferences.getString(keySelectedModes, null)
         val selectedModes = selectedModesString?.split(separatorComma)?.sorted() ?: emptyList()
-        return PassesSettings(hoursAhead, minElevation, selectedModes)
+        return PassesSettings(
+            showDeepSpace,
+            hoursAhead,
+            minElevation,
+            aosStartMinute,
+            aosEndMinute,
+            invertAosTimeWindow,
+            selectedModes
+        )
     }
     //endregion
 
@@ -246,82 +412,56 @@ class SettingsRepo(
     //endregion
 
     //region # RC settings
+    init {
+        migrateRCFormats()
+    }
+
+    // TODO: Remove after a few releases (added in v4.2.0)
+    private val keyRCFormatsMigrated = "rcFormatsMigrated"
+
+    private fun migrateRCFormats() {
+        if (preferences.getBoolean(keyRCFormatsMigrated, false)) return
+        val formatKeys = listOf(
+            keyRotatorFormat, keyFrequencyFormat, keyBluetoothRotatorFormat, keyBluetoothFrequencyFormat
+        )
+        preferences.edit {
+            for (key in formatKeys) {
+                val value = preferences.getString(key, null) ?: continue
+                if (value.contains("_") && !value.startsWith("\\")) {
+                    putString(key, "\\$value")
+                }
+            }
+            putBoolean(keyRCFormatsMigrated, true)
+        }
+    }
+
     private val _rcSettings = MutableStateFlow(getRCSettings())
     override val rcSettings: StateFlow<RCSettings> = _rcSettings
 
-    override fun setBluetoothRotatorAddress(value: String) {
-        preferences.edit { putString(keyBluetoothRotatorAddress, value) }
-        _rcSettings.update { it.copy(bluetoothRotatorAddress = value) }
-    }
-
-    override fun setBluetoothRotatorFormat(value: String) {
-        preferences.edit { putString(keyBluetoothRotatorFormat, value) }
-        _rcSettings.update { it.copy(bluetoothRotatorFormat = value) }
-    }
-
-    override fun setBluetoothRotatorName(value: String) {
-        preferences.edit { putString(keyBluetoothRotatorName, value) }
-        _rcSettings.update { it.copy(bluetoothRotatorName = value) }
-    }
-
-    override fun setBluetoothRotatorState(value: Boolean) {
-        preferences.edit { putBoolean(keyBluetoothRotatorState, value) }
-        _rcSettings.update { it.copy(bluetoothRotatorState = value) }
-    }
-
-    override fun setBluetoothFrequencyState(value: Boolean) {
-        preferences.edit { putBoolean(keyBluetoothFrequencyState, value) }
-        _rcSettings.update { it.copy(bluetoothFrequencyState = value) }
-    }
-
-    override fun setBluetoothFrequencyAddress(value: String) {
-        preferences.edit { putString(keyBluetoothFrequencyAddress, value) }
-        _rcSettings.update { it.copy(bluetoothFrequencyAddress = value) }
-    }
-
-    override fun setBluetoothFrequencyFormat(value: String) {
-        preferences.edit { putString(keyBluetoothFrequencyFormat, value) }
-        _rcSettings.update { it.copy(bluetoothFrequencyFormat = value) }
-    }
-
-    override fun setRotatorAddress(value: String) {
-        preferences.edit { putString(keyRotatorAddress, value) }
-        _rcSettings.update { it.copy(rotatorAddress = value) }
-    }
-
-    override fun setRotatorPort(value: String) {
-        preferences.edit { putString(keyRotatorPort, value) }
-        _rcSettings.update { it.copy(rotatorPort = value) }
-    }
-
-    override fun setRotatorState(value: Boolean) {
-        preferences.edit { putBoolean(keyRotatorState, value) }
-        _rcSettings.update { it.copy(rotatorState = value) }
-    }
-
-    override fun setRotatorFormat(value: String) {
-        preferences.edit { putString(keyRotatorFormat, value) }
-        _rcSettings.update { it.copy(rotatorFormat = value) }
-    }
-
-    override fun setFrequencyState(value: Boolean) {
-        preferences.edit { putBoolean(keyFrequencyState, value) }
-        _rcSettings.update { it.copy(frequencyState = value) }
-    }
-
-    override fun setFrequencyAddress(value: String) {
-        preferences.edit { putString(keyFrequencyAddress, value) }
-        _rcSettings.update { it.copy(frequencyAddress = value) }
-    }
-
-    override fun setFrequencyPort(value: String) {
-        preferences.edit { putString(keyFrequencyPort, value) }
-        _rcSettings.update { it.copy(frequencyPort = value) }
-    }
-
-    override fun setFrequencyFormat(value: String) {
-        preferences.edit { putString(keyFrequencyFormat, value) }
-        _rcSettings.update { it.copy(frequencyFormat = value) }
+    override fun updateRCSettings(settings: RCSettings) {
+        val clampedFreqOffsetHz = settings.frequencyOffsetHz.coerceIn(
+            Constants.FREQ_OFFSET_MIN_HZ,
+            Constants.FREQ_OFFSET_MAX_HZ
+        )
+        preferences.edit {
+            putBoolean(keyRotatorState, settings.rotatorState)
+            putString(keyRotatorAddress, settings.rotatorAddress)
+            putString(keyRotatorPort, settings.rotatorPort)
+            putString(keyRotatorFormat, settings.rotatorFormat)
+            putBoolean(keyFrequencyState, settings.frequencyState)
+            putString(keyFrequencyAddress, settings.frequencyAddress)
+            putString(keyFrequencyPort, settings.frequencyPort)
+            putString(keyFrequencyFormat, settings.frequencyFormat)
+            putLong(keyFrequencyOffsetHz, clampedFreqOffsetHz)
+            putBoolean(keyBluetoothRotatorState, settings.bluetoothRotatorState)
+            putString(keyBluetoothRotatorFormat, settings.bluetoothRotatorFormat)
+            putString(keyBluetoothRotatorName, settings.bluetoothRotatorName)
+            putString(keyBluetoothRotatorAddress, settings.bluetoothRotatorAddress)
+            putBoolean(keyBluetoothFrequencyState, settings.bluetoothFrequencyState)
+            putString(keyBluetoothFrequencyFormat, settings.bluetoothFrequencyFormat)
+            putString(keyBluetoothFrequencyAddress, settings.bluetoothFrequencyAddress)
+        }
+        _rcSettings.value = settings.copy(frequencyOffsetHz = clampedFreqOffsetHz)
     }
 
     private fun getRCSettings(): RCSettings = RCSettings(
@@ -332,14 +472,16 @@ class SettingsRepo(
         frequencyState = preferences.getBoolean(keyFrequencyState, false),
         frequencyAddress = preferences.getString(keyFrequencyAddress, null) ?: "127.0.0.1",
         frequencyPort = preferences.getString(keyFrequencyPort, null) ?: "4532",
-        frequencyFormat = preferences.getString(keyFrequencyFormat, null) ?: $$"set_freq $FREQ",
+        frequencyFormat = preferences.getString(keyFrequencyFormat, null) ?: $$"F $FREQ",
+        frequencyOffsetHz = preferences.getLong(keyFrequencyOffsetHz, 0L)
+            .coerceIn(Constants.FREQ_OFFSET_MIN_HZ, Constants.FREQ_OFFSET_MAX_HZ),
         bluetoothRotatorState = preferences.getBoolean(keyBluetoothRotatorState, false),
-        bluetoothRotatorFormat = preferences.getString(keyBluetoothRotatorFormat, null) ?: $$"W$AZ $EL",
+        bluetoothRotatorFormat = preferences.getString(keyBluetoothRotatorFormat, null) ?: $$"P $AZ $EL",
         bluetoothRotatorName = preferences.getString(keyBluetoothRotatorName, null) ?: "Default",
         bluetoothRotatorAddress = preferences.getString(keyBluetoothRotatorAddress, null) ?: "00:0C:BF:13:80:5D",
         bluetoothFrequencyState = preferences.getBoolean(keyBluetoothFrequencyState, false),
         bluetoothFrequencyAddress = preferences.getString(keyBluetoothFrequencyAddress, null) ?: "00:0C:BF:13:80:5D",
-        bluetoothFrequencyFormat = preferences.getString(keyBluetoothFrequencyFormat, null) ?: $$"FA$FREQ"
+        bluetoothFrequencyFormat = preferences.getString(keyBluetoothFrequencyFormat, null) ?: $$"F $FREQ"
     )
     //endregion
 
@@ -347,39 +489,25 @@ class SettingsRepo(
     private val _otherSettings = MutableStateFlow(getOtherSettings())
     override val otherSettings: StateFlow<OtherSettings> = _otherSettings
 
-    override fun setStateOfAutoUpdate(value: Boolean) {
-        preferences.edit { putBoolean(keyStateOfAutoUpdate, value) }
-        _otherSettings.update { it.copy(stateOfAutoUpdate = value) }
-    }
-
-    override fun setStateOfSensors(value: Boolean) {
-        preferences.edit { putBoolean(keyStateOfSensors, value) }
-        _otherSettings.update { it.copy(stateOfSensors = value) }
-    }
-
-    override fun setStateOfSweep(value: Boolean) {
-        preferences.edit { putBoolean(keyStateOfSweep, value) }
-        _otherSettings.update { it.copy(stateOfSweep = value) }
-    }
-
-    override fun setStateOfUtc(value: Boolean) {
-        preferences.edit { putBoolean(keyStateOfUtc, value) }
-        _otherSettings.update { it.copy(stateOfUtc = value) }
-    }
-
-    override fun setStateOfLightTheme(value: Boolean){
-        preferences.edit { putBoolean(keyStateOfLightTheme, value) }
-        _otherSettings.update { it.copy(stateOfLightTheme = value) }
-    }
-
-    override fun setWarningDismissed() {
-        preferences.edit { putBoolean(keyShouldSeeWarning, false) }
-        _otherSettings.update { it.copy(shouldSeeWarning = false) }
-    }
-
-    override fun setWhatsNewDismissed() {
-        preferences.edit { putBoolean(keyShouldSeeWhatsNew, false) }
-        _otherSettings.update { it.copy(shouldSeeWhatsNew = false) }
+    override fun updateOtherSettings(transform: (OtherSettings) -> OtherSettings) {
+        _otherSettings.update { current ->
+            val new = transform(current)
+            preferences.edit {
+                putBoolean(keyStateOfAutoUpdate, new.stateOfAutoUpdate)
+                putBoolean(keyStateOfSensors, new.stateOfSensors)
+                putBoolean(keyStateOfSweep, new.stateOfSweep)
+                putBoolean(keyStateOfUtc, new.stateOfUtc)
+                putBoolean(keyStateOfLightTheme, new.stateOfLightTheme)
+                putBoolean(keyStateOfNightMode, new.stateOfNightMode)
+                putBoolean(keyStateOfMapGrid, new.stateOfMapGrid)
+                putBoolean(keyShouldSeeWarning, new.shouldSeeWarning)
+                putBoolean(keyShouldSeeWhatsNew, new.shouldSeeWhatsNew)
+                putString(keySstvMode, new.sstvMode)
+                putLong(keyLowElevation, new.lowElevation.toRawBits())
+                putLong(keyHighElevation, new.highElevation.toRawBits())
+            }
+            new
+        }
     }
 
     private fun getOtherSettings(): OtherSettings = OtherSettings(
@@ -388,8 +516,13 @@ class SettingsRepo(
         stateOfSweep = preferences.getBoolean(keyStateOfSweep, true),
         stateOfUtc = preferences.getBoolean(keyStateOfUtc, false),
         stateOfLightTheme = preferences.getBoolean(keyStateOfLightTheme, false),
+        stateOfNightMode = preferences.getBoolean(keyStateOfNightMode, false),
+        stateOfMapGrid = preferences.getBoolean(keyStateOfMapGrid, false),
         shouldSeeWarning = preferences.getBoolean(keyShouldSeeWarning, true),
-        shouldSeeWhatsNew = preferences.getBoolean(keyShouldSeeWhatsNew, true)
+        shouldSeeWhatsNew = preferences.getBoolean(keyShouldSeeWhatsNew, true),
+        sstvMode = preferences.getString(keySstvMode, null) ?: "Auto",
+        lowElevation = Double.fromBits(preferences.getLong(keyLowElevation, 15.0.toRawBits())),
+        highElevation = Double.fromBits(preferences.getLong(keyHighElevation, 45.0.toRawBits()))
     )
     //endregion
 
@@ -397,31 +530,198 @@ class SettingsRepo(
     private val _dataSourcesSettings = MutableStateFlow(getDataSourcesSettings())
     override val dataSourcesSettings: StateFlow<DataSourcesSettings> = _dataSourcesSettings
 
-    override fun setUseCustomTle(value: Boolean) {
-        preferences.edit { putBoolean(keyUseCustomTle, value) }
-        _dataSourcesSettings.update { it.copy(useCustomTLE = value) }
-    }
-
-    override fun setUseCustomTransceivers(value: Boolean) {
-        preferences.edit { putBoolean(keyUseCustomTransceivers, value) }
-        _dataSourcesSettings.update { it.copy(useCustomTransceivers = value) }
-    }
-
-    override fun setTleUrl(value: String) {
-        preferences.edit { putString(keyTleUrl, value) }
-        _dataSourcesSettings.update { it.copy(tleUrl = value) }
-    }
-
-    override fun setTransceiversUrl(value: String) {
-        preferences.edit { putString(keyTransceiversUrl, value) }
-        _dataSourcesSettings.update { it.copy(transceiversUrl = value) }
+    override fun updateDataSourcesSettings(settings: DataSourcesSettings) {
+        // Normalize the enabled lists so they are positionally aligned with the URL lists.
+        // Missing entries default to enabled (true), keeping the persisted "one flag per URL"
+        // invariant intact even when a default empty list is used to construct the model.
+        val normalized = settings.copy(
+            satelliteEnabled = alignFlags(settings.satelliteUrls, settings.satelliteEnabled),
+            transceiversEnabled = alignFlags(settings.transceiversUrls, settings.transceiversEnabled)
+        )
+        preferences.edit {
+            putString(keySatelliteUrls, normalized.satelliteUrls.joinToString(separatorUrl))
+            putString(keyTransceiversUrls, normalized.transceiversUrls.joinToString(separatorUrl))
+            putString(keySatelliteEnabled, normalized.satelliteEnabled.joinToString(separatorComma))
+            putString(keyTransceiversEnabled, normalized.transceiversEnabled.joinToString(separatorComma))
+            putBoolean(keySatnogsTleSourceMigration, true)
+        }
+        _dataSourcesSettings.value = normalized
     }
 
     private fun getDataSourcesSettings(): DataSourcesSettings = DataSourcesSettings(
-        useCustomTLE = preferences.getBoolean(keyUseCustomTle, false),
-        useCustomTransceivers = preferences.getBoolean(keyUseCustomTransceivers, false),
-        tleUrl = preferences.getString(keyTleUrl, "https://example.com/tle.txt") ?: "",
-        transceiversUrl = preferences.getString(keyTransceiversUrl, "https://example.com/radio.json") ?: ""
+        satelliteUrls = getDataSourceUrls(
+            key = keySatelliteUrls,
+            defaultUrls = Sources.satelliteDataUrls.values.filter { it.isNotBlank() },
+            legacyEnabledKey = keyUseCustomTle,
+            legacyUrlKey = keyTleUrl
+        ).migrateSatnogsTleSource(),
+        transceiversUrls = getDataSourceUrls(
+            key = keyTransceiversUrls,
+            defaultUrls = Sources.transceiversDataUrls.values.filter { it.isNotBlank() },
+            legacyEnabledKey = keyUseCustomTransceivers,
+            legacyUrlKey = keyTransceiversUrl
+        ),
+        satelliteEnabled = readEnabledFlags(keySatelliteEnabled),
+        transceiversEnabled = readEnabledFlags(keyTransceiversEnabled)
+    )
+
+    /** Read the persisted per-source enabled flags (empty when never stored). */
+    private fun readEnabledFlags(key: String): List<Boolean> {
+        return preferences.getString(key, null)
+            ?.split(separatorComma)
+            ?.mapNotNull { it.trim() }
+            ?.filter { it == "true" || it == "false" }
+            ?.map { it == "true" }
+            ?: emptyList()
+    }
+
+    /** Keep the flags positionally aligned with the URL list, defaulting to enabled. */
+    private fun alignFlags(urls: List<String>, flags: List<Boolean>): List<Boolean> {
+        if (flags.size >= urls.size) return flags.take(urls.size)
+        return flags + List(urls.size - flags.size) { true }
+    }
+
+    private fun getDataSourceUrls(
+        key: String,
+        defaultUrls: List<String>,
+        legacyEnabledKey: String,
+        legacyUrlKey: String
+    ): List<String> {
+        val stored = preferences.getString(key, null)
+            ?.split(separatorUrl)
+            ?.map { it.trim() }
+            ?.filter { it.isNotBlank() }
+        if (stored != null) return stored
+        val legacyCustomUrl = preferences.getString(legacyUrlKey, null)?.trim().orEmpty()
+        return if (preferences.getBoolean(legacyEnabledKey, false) && legacyCustomUrl.isNotBlank()) {
+            (defaultUrls + legacyCustomUrl).distinct()
+        } else {
+            defaultUrls
+        }
+    }
+
+    private fun List<String>.migrateSatnogsTleSource(): List<String> {
+        if (preferences.getBoolean(keySatnogsTleSourceMigration, false)) return this
+        val satnogsTleUrl = Sources.satelliteDataUrls["SatNOGS"].orEmpty()
+        if (satnogsTleUrl.isBlank() || containsSourceUrl(satnogsTleUrl)) return this
+        val celestrakSatnogsIndex = indexOfFirst { isSameSourceUrl(it, legacyCelestrakSatnogsUrl) }
+        if (celestrakSatnogsIndex < 0) return this
+
+        val migrated = toMutableList().apply { add(celestrakSatnogsIndex + 1, satnogsTleUrl) }
+        preferences.edit {
+            putString(keySatelliteUrls, migrated.joinToString(separatorUrl))
+            putBoolean(keySatnogsTleSourceMigration, true)
+        }
+        return migrated
+    }
+
+    private fun List<String>.containsSourceUrl(url: String): Boolean = any { isSameSourceUrl(it, url) }
+
+    private fun isSameSourceUrl(first: String, second: String): Boolean =
+        normalizeSourceUrl(first).equals(normalizeSourceUrl(second), ignoreCase = true)
+
+    private fun normalizeSourceUrl(url: String): String {
+        val trimmed = url.trim()
+        return if (trimmed.startsWith("http", ignoreCase = true)) trimmed else "https://$trimmed"
+    }
+    //endregion
+
+    //region # Data sources status
+    private val _dataSourcesStatus = MutableStateFlow<Map<String, Int>>(emptyMap())
+    override val dataSourcesStatus: StateFlow<Map<String, Int>> = _dataSourcesStatus
+
+    override fun updateDataSourcesStatus(status: Map<String, Int>) {
+        _dataSourcesStatus.value = status
+    }
+    //endregion
+
+    //region # Radio control settings
+    private val keyRadioControlEnabled = "radioControlEnabled"
+    private val keyRadioModel = "radioModel"
+    private val keyTxRadioAddress = "txRadioAddress"
+    private val keyRxRadioAddress = "rxRadioAddress"
+    private val keyTxRadioName = "txRadioName"
+    private val keyRxRadioName = "rxRadioName"
+    private val keyRadioBaudRate = "radioBaudRate"
+    private val keyRadioSplitMode = "radioSplitMode"
+
+    private val _radioControlSettings = MutableStateFlow(getRadioControlSettings())
+    override val radioControlSettings: StateFlow<RadioControlSettings> = _radioControlSettings
+
+    override fun updateRadioControlSettings(settings: RadioControlSettings) {
+        preferences.edit {
+            putBoolean(keyRadioControlEnabled, settings.enabled)
+            putString(keyRadioModel, settings.radioModel)
+            putString(keyTxRadioAddress, settings.txRadioAddress)
+            putString(keyRxRadioAddress, settings.rxRadioAddress)
+            putString(keyTxRadioName, settings.txRadioName)
+            putString(keyRxRadioName, settings.rxRadioName)
+            putInt(keyRadioBaudRate, settings.baudRate)
+            putBoolean(keyRadioSplitMode, settings.splitMode)
+        }
+        _radioControlSettings.value = settings
+    }
+
+    private fun getRadioControlSettings(): RadioControlSettings = RadioControlSettings(
+        enabled = preferences.getBoolean(keyRadioControlEnabled, false),
+        radioModel = preferences.getString(keyRadioModel, null) ?: RadioControlSettings.MODEL_YAESU_FT817,
+        txRadioAddress = preferences.getString(keyTxRadioAddress, null) ?: "",
+        rxRadioAddress = preferences.getString(keyRxRadioAddress, null) ?: "",
+        txRadioName = preferences.getString(keyTxRadioName, null) ?: "TX Radio",
+        rxRadioName = preferences.getString(keyRxRadioName, null) ?: "RX Radio",
+        baudRate = preferences.getInt(keyRadioBaudRate, 4800),
+        splitMode = preferences.getBoolean(keyRadioSplitMode, false)
     )
     //endregion
+
+    //region # Per-satellite calculator offset settings
+    private val keySatelliteOffsets = "satelliteOffsets"
+    private val keyLegacySatelliteOffsetPrefix = "offset_khz_"
+
+    override fun getSatelliteOffset(catnum: Int): String {
+        val json = preferences.getString(keySatelliteOffsets, "{}") ?: "{}"
+        val stored = try {
+            JSONObject(json).optString(catnum.toString(), "")
+        } catch (_: Exception) {
+            ""
+        }
+        if (stored.isNotEmpty()) return stored
+
+        // Lazy migration from the fork's old UI-layer implementation, which stored
+        // one SharedPreferences entry per satellite directly from TransceiversPage.
+        val legacyKey = "$keyLegacySatelliteOffsetPrefix$catnum"
+        val legacy = preferences.getString(legacyKey, "").orEmpty()
+        if (legacy.isNotEmpty()) {
+            setSatelliteOffset(catnum, legacy)
+        }
+        return legacy
+    }
+
+    override fun setSatelliteOffset(catnum: Int, offset: String) {
+        val json = preferences.getString(keySatelliteOffsets, "{}") ?: "{}"
+        val updated = try {
+            val obj = JSONObject(json)
+            if (offset.isEmpty()) obj.remove(catnum.toString()) else obj.put(catnum.toString(), offset)
+            obj.toString()
+        } catch (_: Exception) {
+            if (offset.isEmpty()) "{}" else """{"$catnum": "$offset"}"""
+        }
+        preferences.edit {
+            putString(keySatelliteOffsets, updated)
+            remove("$keyLegacySatelliteOffsetPrefix$catnum")
+        }
+    }
+    //endregion
+
+    //region # AMSAT status report settings
+    private val keyAmSatCallsign = "amSatCallsign"
+
+    override fun getAmSatCallsign(): String {
+        return preferences.getString(keyAmSatCallsign, "").orEmpty()
+    }
+
+    override fun setAmSatCallsign(callsign: String) {
+        preferences.edit { putString(keyAmSatCallsign, callsign.trim().uppercase(Locale.US)) }
+    }
+    //endregion
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/UpdateRepository.kt

@@ -0,0 +1,106 @@
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.model.LatestRelease
+import com.rtbishop.look4sat.core.domain.repository.IUpdateRepository
+import com.rtbishop.look4sat.core.domain.source.IRemoteSource
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import java.io.File
+
+class UpdateRepository(
+    private val remoteSource: IRemoteSource
+) : IUpdateRepository {
+
+    override suspend fun getLatestRelease(): LatestRelease? = withContext(Dispatchers.IO) {
+        // Use the GitHub releases web page instead of the REST API endpoint:
+        // the API endpoint is rate-limited to 60 requests/hour per IP, which is
+        // quickly exhausted on shared egress IPs (e.g. VPN proxies), causing 403
+        // failures. The web endpoint redirects to the latest tag with no such limit.
+        // When GitHub is unreachable (common on mainland-China networks without a
+        // proxy), fall back to community GitHub accelerator mirrors that proxy the
+        // same page; each mirror resolves the identical tag and asset URLs.
+        for (baseUrl in LATEST_RELEASE_URLS) {
+            val result = remoteSource.getNetworkStream(baseUrl)
+            val stream = result.stream ?: continue
+            val parsed = try {
+                parseRelease(stream.bufferedReader().use { it.readText() }, baseUrl)
+            } catch (e: Exception) {
+                println("UpdateRepository parse failure: $e")
+                null
+            }
+            if (parsed != null) return@withContext parsed
+        }
+        null
+    }
+
+    override suspend fun downloadApk(url: String, dest: File): Boolean = withContext(Dispatchers.IO) {
+        if (url.isBlank()) return@withContext false
+        val result = remoteSource.getNetworkStream(url)
+        val stream = result.stream ?: return@withContext false
+        try {
+            dest.outputStream().use { out -> stream.use { it.copyTo(out) } }
+            true
+        } catch (e: Exception) {
+            println("UpdateRepository download failure: $e")
+            false
+        }
+    }
+
+    private fun parseRelease(html: String, sourceUrl: String): LatestRelease? {
+        // The redirect target is the latest release's tag page. Extract the tag
+        // from the og:url meta tag ("…/releases/tag/v4.4.6-ba7opf.8") — stable and
+        // unambiguous. The <title> also holds the release name, but that is free
+        // text and cannot be used to build the asset URL.
+        val ogUrl = Regex("<meta\\s+property=\"og:url\"\\s+content=\"([^\"]*)\"").find(html)
+            ?.groupValues?.get(1) ?: return null
+        val tag = Regex("/releases/tag/(v[0-9][0-9A-Za-z.\\-]*)$").find(ogUrl)
+            ?.groupValues?.get(1) ?: return null
+        val title = Regex("<title>(.*?)</title>", RegexOption.DOT_MATCHES_ALL)
+            .find(html)?.groupValues?.get(1)?.trim()
+            ?.substringBefore("·")?.removePrefix("Release")?.trim() ?: tag
+        // Release notes live in the page's markdown-body section (first occurrence
+        // is the release description). Strip HTML tags for plain-text display.
+        val raw = Regex("<div[^>]*class=\"[^\"]*markdown-body[^\"]*\"[^>]*>(.*?)</div>", RegexOption.DOT_MATCHES_ALL)
+            .find(html)?.groupValues?.get(1) ?: ""
+        val body = raw.replace(Regex("<[^>]+>"), "")
+            .replace("&lt;", "<").replace("&gt;", ">").replace("&amp;", "&")
+            .replace("&quot;", "\"").replace("&#39;", "'")
+            .trim()
+        // The release APK asset naming: Look4Sat-<tag without leading v>.apk
+        // (since v4.4.6-ba7opf.9.9 the releases are uploaded with the bare
+        // versioned filename, no "-release" suffix). When the page was fetched
+        // through an accelerator mirror (https://<mirror>/https://github.com/...),
+        // download through the same mirror — raw github.com is unreachable on the
+        // networks that needed the mirror in the first place.
+        val mirrorPrefix = sourceUrl.substringBefore("https://github.com")
+        val apkName = "Look4Sat-${tag.removePrefix("v")}.apk"
+        val apkUrl = if (mirrorPrefix.isEmpty()) {
+            "$DOWNLOAD_BASE_URL/$tag/$apkName"
+        } else {
+            "${mirrorPrefix}https://github.com/atsunatsu/Look4Sat/releases/download/$tag/$apkName"
+        }
+        return LatestRelease(
+            versionTag = tag,
+            title = title,
+            body = body,
+            apkUrl = apkUrl
+        )
+    }
+
+    private companion object {
+        // Web pages are used instead of api.github.com to avoid the 60 req/hour
+        // anonymous rate limit (see getLatestRelease above). The GitHub URL is
+        // tried first; if it is unreachable (no proxy on mainland networks) the
+        // accelerator mirrors are tried in order. Download URLs always point at
+        // the mirrors too — raw github.com release downloads are equally blocked
+        // without a proxy, so a mirror-resolved tag must be downloaded via the
+        // same mirror.
+        val LATEST_RELEASE_URLS = listOf(
+            "https://github.com/atsunatsu/Look4Sat/releases/latest",
+            "https://ghfast.top/https://github.com/atsunatsu/Look4Sat/releases/latest",
+            "https://gh.llkk.cc/https://github.com/atsunatsu/Look4Sat/releases/latest",
+            "https://github.moeyy.xyz/https://github.com/atsunatsu/Look4Sat/releases/latest"
+        )
+        const val DOWNLOAD_BASE_URL = "https://github.com/atsunatsu/Look4Sat/releases/download"
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/WavelogRepository.kt

@@ -0,0 +1,97 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.repository.IWavelogRepository
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import org.json.JSONArray
+import org.json.JSONObject
+
+/**
+ * Fetches the list of worked gridsquares from a self-hosted Wavelog instance.
+ *
+ * Uses the Wavelog v1 API endpoint (verified against Wavelog 3.0.2):
+ *   POST {base}/index.php/api/logbook_get_worked_grids
+ *   Body: {"key": "<api key>", "logbook_id": "<logbook id>"}
+ *   Response 201: JSON array of 4-char gridsquares, e.g. ["JN47","JO30"]
+ *   (see Wavelog Api.php logbook_get_worked_grids / Api_model::get_grids_worked_in_logbook)
+ *
+ * The token field carries "<api_key>:<logbook_id>" so one credential line
+ * configures both values (the dialog explains this to the user).
+ */
+class WavelogRepository : IWavelogRepository {
+
+    override suspend fun fetchWorkedGrids(url: String, token: String): Set<String>? = withContext(Dispatchers.IO) {
+        val parts = token.trim().split(":")
+        val apiKey = parts.getOrNull(0)?.trim().orEmpty()
+        val logbookId = parts.getOrNull(1)?.trim().orEmpty()
+        if (url.isBlank() || apiKey.isBlank() || logbookId.isBlank()) return@withContext null
+        val base = url.trim().trimEnd('/')
+        val requestUrl = "$base/index.php/api/logbook_get_worked_grids"
+        try {
+            val connection = java.net.URL(requestUrl).openConnection() as java.net.HttpURLConnection
+            connection.connectTimeout = 10_000
+            connection.readTimeout = 15_000
+            connection.requestMethod = "POST"
+            connection.doOutput = true
+            connection.setRequestProperty("Content-Type", "application/json")
+            val body = JSONObject().apply {
+                put("key", apiKey)
+                put("logbook_id", logbookId)
+            }.toString().toByteArray()
+            connection.outputStream.use { it.write(body) }
+            val code = connection.responseCode
+            if (code !in 200..299) {
+                connection.disconnect()
+                return@withContext null
+            }
+            val response = connection.inputStream.bufferedReader().use { it.readText() }
+            connection.disconnect()
+            parseWorkedGrids(response)
+        } catch (e: Exception) {
+            println("WavelogRepository fetch failure: $e")
+            null
+        }
+    }
+
+    internal fun parseWorkedGrids(body: String): Set<String>? {
+        return try {
+            val array = when {
+                body.trimStart().startsWith("[") -> JSONArray(body)
+                else -> {
+                    // Tolerate {"grids": [...]} wrappers too
+                    JSONObject(body).optJSONArray("grids") ?: return null
+                }
+            }
+            val result = mutableSetOf<String>()
+            for (i in 0 until array.length()) {
+                val grid = array.optString(i, "").trim().uppercase()
+                // Keep only well-formed 4-character Maidenhead squares (e.g. OL62)
+                if (grid.length == 4 && grid[0] in 'A'..'R' && grid[1] in 'A'..'R'
+                    && grid[2] in '0'..'9' && grid[3] in '0'..'9'
+                ) {
+                    result.add(grid)
+                }
+            }
+            result
+        } catch (_: Exception) {
+            null
+        }
+    }
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/source/LocalSource.kt

@@ -74,7 +74,6 @@ class LocalSource(private val look4SatDao: Look4SatDao) : ILocalSource {
     }
 
     override suspend fun insertRadios(radios: List<SatRadio>) {
-        look4SatDao.deleteRadios()
         look4SatDao.insertRadios(radios.toFrameworkRadios())
     }
 

core/data/src/main/java/com/rtbishop/look4sat/core/data/source/RemoteSource.kt

@@ -20,10 +20,13 @@ package com.rtbishop.look4sat.core.data.source
 import android.content.ContentResolver
 import androidx.core.net.toUri
 import com.rtbishop.look4sat.core.domain.source.IRemoteSource
+import com.rtbishop.look4sat.core.domain.source.NetworkResult
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.withContext
+import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
 import okhttp3.Request
+import okhttp3.RequestBody.Companion.toRequestBody
 import java.io.InputStream
 
 class RemoteSource(
@@ -42,12 +45,74 @@ class RemoteSource(
         }
     }
 
-    override suspend fun getNetworkStream(url: String): InputStream? = withContext(dispatcher) {
+    override suspend fun getNetworkStream(url: String): NetworkResult = withContext(dispatcher) {
         try {
             val networkRequest = Request.Builder().url(url).build()
-            httpClient.newCall(networkRequest).execute().body.byteStream()
+            val response = httpClient.newCall(networkRequest).execute()
+            if (!response.isSuccessful) {
+                val code = response.code
+                response.close()
+                return@withContext NetworkResult(code, null)
+            }
+            // Return the body stream directly as the caller is responsible for closing it.
+            // Closing the stream returns the connection to OkHttp's pool.
+            val body = response.body
+            if (body == null) {
+                response.close()
+                return@withContext NetworkResult(response.code, null)
+            }
+            NetworkResult(response.code, body.byteStream().buffered())
         } catch (exception: Exception) {
             println("RemoteSource network stream exception: $exception")
+            NetworkResult(NetworkResult.CONNECTION_ERROR, null)
+        }
+    }
+
+    override suspend fun getAmSatCatalog(): String? = withContext(dispatcher) {
+        try {
+            val request = Request.Builder()
+                .url("https://www.amsat.org/status/api/v1/catalog.php")
+                .header("User-Agent", "Look4Sat")
+                .build()
+            httpClient.newCall(request).execute().use { response ->
+                if (!response.isSuccessful) return@use null
+                response.body.string()
+            }
+        } catch (exception: Exception) {
+            println("RemoteSource getAmSatCatalog exception: $exception")
+            null
+        }
+    }
+
+    override suspend fun getAmSatReports(hours: Int, limit: Int): String? = withContext(dispatcher) {
+        try {
+            val request = Request.Builder()
+                .url("https://www.amsat.org/status/api/v1/reports.php?hours=$hours&limit=$limit")
+                .header("User-Agent", "Look4Sat")
+                .build()
+            httpClient.newCall(request).execute().use { response ->
+                if (!response.isSuccessful) return@use null
+                response.body.string()
+            }
+        } catch (exception: Exception) {
+            println("RemoteSource getAmSatReports exception: $exception")
+            null
+        }
+    }
+
+    override suspend fun submitAmSatReport(payloadJson: String): Pair<Int, String>? = withContext(dispatcher) {
+        try {
+            val body = payloadJson.toRequestBody("application/json; charset=utf-8".toMediaType())
+            val request = Request.Builder()
+                .url("https://www.amsat.org/status/api/v1/reports.php")
+                .header("User-Agent", "Look4Sat")
+                .post(body)
+                .build()
+            httpClient.newCall(request).execute().use { response ->
+                response.code to response.body.string()
+            }
+        } catch (exception: Exception) {
+            println("RemoteSource submitAmSatReport exception: $exception")
             null
         }
     }

core/data/src/main/java/com/rtbishop/look4sat/core/data/usecase/AudioCapture.kt

@@ -0,0 +1,63 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.usecase
+
+import android.media.AudioFormat
+import android.media.AudioRecord
+import android.media.MediaRecorder
+import androidx.annotation.RequiresPermission
+import com.rtbishop.look4sat.core.domain.usecase.IAudioCapture
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.currentCoroutineContext
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.isActive
+
+class AudioCapture : IAudioCapture {
+
+    override val sampleRate: Int = 44100
+
+    private val channelConfig = AudioFormat.CHANNEL_IN_MONO
+    private val audioFormat = AudioFormat.ENCODING_PCM_FLOAT
+    private val bufferSize = AudioRecord.getMinBufferSize(sampleRate, channelConfig, audioFormat)
+        .coerceAtLeast(sampleRate) // at least 1 second buffer
+
+    @RequiresPermission(android.Manifest.permission.RECORD_AUDIO)
+    override fun audioFlow(): Flow<FloatArray> = flow {
+        val recorder = AudioRecord(
+            MediaRecorder.AudioSource.MIC,
+            sampleRate,
+            channelConfig,
+            audioFormat,
+            bufferSize * 4 // bytes for float
+        )
+        try {
+            recorder.startRecording()
+            val chunkSize = sampleRate / 10 // ~100ms chunks
+            val buffer = FloatArray(chunkSize)
+            while (currentCoroutineContext().isActive) {
+                val read = recorder.read(buffer, 0, chunkSize, AudioRecord.READ_BLOCKING)
+                if (read > 0) emit(if (read == chunkSize) buffer.copyOf() else buffer.copyOfRange(0, read))
+            }
+        } finally {
+            recorder.stop()
+            recorder.release()
+        }
+    }.flowOn(Dispatchers.IO)
+}

core/data/src/main/java/com/rtbishop/look4sat/core/data/usecase/SaveImage.kt

@@ -0,0 +1,84 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.usecase
+
+import android.content.ContentValues
+import android.content.Context
+import android.graphics.Bitmap
+import android.os.Build
+import android.os.Environment
+import android.provider.MediaStore
+import com.rtbishop.look4sat.core.domain.usecase.ISaveImage
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import java.io.File
+import java.io.FileOutputStream
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+
+//Saves images to the device gallery using MediaStore (API 29+) or direct file write (API < 29)
+class SaveImage(private val context: Context) : ISaveImage {
+
+    override suspend fun invoke(pixels: IntArray, width: Int, height: Int, modeName: String): Boolean {
+        return withContext(Dispatchers.IO) {
+            try {
+                val bitmap = Bitmap.createBitmap(pixels, width, height, Bitmap.Config.ARGB_8888)
+                val timestamp = SimpleDateFormat("yyyyMMdd_HHmmss", Locale.US).format(Date())
+                val filename = "SSTV_${modeName}_$timestamp.png"
+                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
+                    saveWithMediaStore(bitmap, filename)
+                } else {
+                    saveToExternalStorage(bitmap, filename)
+                }
+                bitmap.recycle()
+                true
+            } catch (_: Exception) {
+                false
+            }
+        }
+    }
+
+    private fun saveWithMediaStore(bitmap: Bitmap, filename: String) {
+        val values = ContentValues().apply {
+            put(MediaStore.Images.Media.DISPLAY_NAME, filename)
+            put(MediaStore.Images.Media.MIME_TYPE, "image/png")
+            put(MediaStore.Images.Media.RELATIVE_PATH, "${Environment.DIRECTORY_PICTURES}/Look4Sat")
+            put(MediaStore.Images.Media.IS_PENDING, 1)
+        }
+        val resolver = context.contentResolver
+        val uri = resolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
+            ?: throw IllegalStateException("Failed to create MediaStore entry")
+        resolver.openOutputStream(uri)?.use { stream ->
+            bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream)
+        }
+        values.clear()
+        values.put(MediaStore.Images.Media.IS_PENDING, 0)
+        resolver.update(uri, values, null, null)
+    }
+
+    private fun saveToExternalStorage(bitmap: Bitmap, filename: String) {
+        val picturesDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES)
+        val dir = File(picturesDir, "Look4Sat")
+        if (!dir.exists()) dir.mkdirs()
+        val file = File(dir, filename)
+        FileOutputStream(file).use { stream ->
+            bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream)
+        }
+    }
+}

core/data/src/test/java/com/rtbishop/look4sat/core/data/framework/Ft817CatProtocolTest.kt

@@ -0,0 +1,150 @@
+package com.rtbishop.look4sat.core.data.framework
+
+import org.junit.Assert.assertArrayEquals
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertNull
+import org.junit.Test
+
+class Ft817CatProtocolTest {
+
+    @Test
+    fun encodeFrequencyBcd_145500000() {
+        val bcd = Ft817CatProtocol.encodeFrequencyBcd(145500000L)
+        assertArrayEquals(byteArrayOf(0x14, 0x55, 0x00, 0x00), bcd)
+    }
+
+    @Test
+    fun encodeFrequencyBcd_435100000() {
+        val bcd = Ft817CatProtocol.encodeFrequencyBcd(435100000L)
+        assertArrayEquals(byteArrayOf(0x43, 0x51, 0x00, 0x00), bcd)
+    }
+
+    @Test
+    fun encodeFrequencyBcd_7074000() {
+        val bcd = Ft817CatProtocol.encodeFrequencyBcd(7074000L)
+        assertArrayEquals(byteArrayOf(0x00, 0x70, 0x74, 0x00), bcd)
+    }
+
+    @Test
+    fun decodeFrequencyBcd_roundTrips() {
+        val testFreqs = listOf(145500000L, 435100000L, 7074000L, 14200000L, 28500000L)
+        for (freq in testFreqs) {
+            val rounded = (freq / 10) * 10
+            val bcd = Ft817CatProtocol.encodeFrequencyBcd(freq)
+            assertEquals(rounded, Ft817CatProtocol.decodeFrequencyBcd(bcd))
+        }
+    }
+
+    @Test
+    fun buildSetFreqCommand_correctFormat() {
+        val cmd = Ft817CatProtocol.buildSetFreqCommand(145500000L)
+        assertEquals(5, cmd.size)
+        assertEquals(0x01.toByte(), cmd[4])
+        assertArrayEquals(byteArrayOf(0x14, 0x55, 0x00, 0x00, 0x01), cmd)
+    }
+
+    @Test
+    fun buildSetModeCommand_usb() {
+        val cmd = Ft817CatProtocol.buildSetModeCommand("USB")
+        assertNotNull(cmd)
+        assertArrayEquals(byteArrayOf(0x01, 0x00, 0x00, 0x00, 0x07), cmd)
+    }
+
+    @Test
+    fun buildSetModeCommand_fm() {
+        val cmd = Ft817CatProtocol.buildSetModeCommand("FM")
+        assertNotNull(cmd)
+        assertArrayEquals(byteArrayOf(0x08, 0x00, 0x00, 0x00, 0x07), cmd)
+    }
+
+    @Test
+    fun buildSetModeCommand_unknownReturnsNull() {
+        assertNull(Ft817CatProtocol.buildSetModeCommand("INVALID"))
+    }
+
+    @Test
+    fun encodeCtcssTone_67_0() {
+        val bcd = Ft817CatProtocol.encodeCtcssToneBcd(67.0)
+        assertArrayEquals(byteArrayOf(0x06, 0x70), bcd)
+    }
+
+    @Test
+    fun encodeCtcssTone_74_4() {
+        val bcd = Ft817CatProtocol.encodeCtcssToneBcd(74.4)
+        assertArrayEquals(byteArrayOf(0x07, 0x44), bcd)
+    }
+
+    @Test
+    fun encodeCtcssTone_141_3() {
+        val bcd = Ft817CatProtocol.encodeCtcssToneBcd(141.3)
+        assertArrayEquals(byteArrayOf(0x14, 0x13), bcd)
+    }
+
+    @Test
+    fun buildSetCtcssToneCommand_correctFormat() {
+        val cmd = Ft817CatProtocol.buildSetCtcssToneCommand(67.0)
+        assertEquals(5, cmd.size)
+        assertEquals(0x0B.toByte(), cmd[4])
+        assertArrayEquals(byteArrayOf(0x06, 0x70, 0x00, 0x00, 0x0B), cmd)
+    }
+
+    @Test
+    fun buildCtcssModeCommand_enable() {
+        val cmd = Ft817CatProtocol.buildCtcssModeCommand(true)
+        assertArrayEquals(byteArrayOf(0x2A, 0x00, 0x00, 0x00, 0x0A), cmd)
+    }
+
+    @Test
+    fun buildCtcssModeCommand_disable() {
+        val cmd = Ft817CatProtocol.buildCtcssModeCommand(false)
+        assertEquals(0x8A.toByte(), cmd[0])
+        assertEquals(0x0A.toByte(), cmd[4])
+    }
+
+    @Test
+    fun parseReadResponse_validResponse() {
+        val response = byteArrayOf(0x14, 0x55, 0x00, 0x00, 0x01)
+        val result = Ft817CatProtocol.parseReadResponse(response)
+        assertNotNull(result)
+        result ?: return
+        assertEquals(145500000L, result.first)
+        assertEquals("USB", result.second)
+    }
+
+    @Test
+    fun parseReadResponse_fmMode() {
+        val response = byteArrayOf(0x14, 0x60, 0x00, 0x00, 0x08)
+        val result = Ft817CatProtocol.parseReadResponse(response)
+        assertNotNull(result)
+        result ?: return
+        assertEquals(146000000L, result.first)
+        assertEquals("FM", result.second)
+    }
+
+    @Test
+    fun parseReadResponse_tooShort() {
+        assertNull(Ft817CatProtocol.parseReadResponse(byteArrayOf(0x14, 0x55, 0x00)))
+    }
+
+    @Test
+    fun parseReadResponse_unknownMode() {
+        val response = byteArrayOf(0x14, 0x55, 0x00, 0x00, 0x0F)
+        assertNull(Ft817CatProtocol.parseReadResponse(response))
+    }
+
+    @Test
+    fun buildPttCommands() {
+        val on = Ft817CatProtocol.buildPttOnCommand()
+        assertArrayEquals(byteArrayOf(0x00, 0x00, 0x00, 0x00, 0x08), on)
+
+        val off = Ft817CatProtocol.buildPttOffCommand()
+        assertEquals(0x88.toByte(), off[4])
+    }
+
+    @Test
+    fun buildReadCommand() {
+        val cmd = Ft817CatProtocol.buildReadFreqModeCommand()
+        assertArrayEquals(byteArrayOf(0x00, 0x00, 0x00, 0x00, 0x03), cmd)
+    }
+}

core/data/src/test/java/com/rtbishop/look4sat/core/data/repository/AmSatRepositoryTest.kt

@@ -0,0 +1,107 @@
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.model.SatStatus
+import com.rtbishop.look4sat.core.domain.model.SatStatusPage
+import com.rtbishop.look4sat.core.domain.source.IRemoteSource
+import com.rtbishop.look4sat.core.domain.source.NetworkResult
+import kotlinx.coroutines.async
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.test.runTest
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertSame
+import org.junit.Test
+import java.io.InputStream
+
+class AmSatRepositoryTest {
+
+    @Test
+    fun fetchStatusReturnsSeededCacheUntilCacheIsCleared() = runTest {
+        val remoteSource = FakeAmSatRemoteSource()
+        val repository = AmSatRepository(remoteSource)
+        val cachedPage = SatStatusPage(
+            fetchedAtUtcMs = 123L,
+            statuses = listOf(SatStatus(name = "AO-7", days = emptyList())),
+            reports = emptyMap()
+        )
+        repository.seedStatusCache(cachedPage)
+
+        val firstPage = repository.fetchStatus()
+        val secondPage = repository.fetchStatus()
+
+        assertSame(cachedPage, firstPage)
+        assertSame(cachedPage, secondPage)
+        assertSame(cachedPage, repository.getCachedStatus())
+        assertEquals(0, remoteSource.catalogRequests)
+        assertEquals(0, remoteSource.reportRequests)
+
+        repository.clearStatusCache()
+        assertNull(repository.getCachedStatus())
+        repository.fetchStatus()
+
+        assertEquals(1, remoteSource.catalogRequests)
+        assertEquals(1, remoteSource.reportRequests)
+    }
+
+    @Test
+    fun forceRefreshBypassesCachedPage() = runTest {
+        val remoteSource = FakeAmSatRemoteSource()
+        val repository = AmSatRepository(remoteSource)
+        repository.seedStatusCache(
+            SatStatusPage(
+                fetchedAtUtcMs = 123L,
+                statuses = listOf(SatStatus(name = "AO-7", days = emptyList())),
+                reports = emptyMap()
+            )
+        )
+
+        repository.fetchStatus(forceRefresh = true)
+
+        assertEquals(1, remoteSource.catalogRequests)
+        assertEquals(1, remoteSource.reportRequests)
+    }
+
+    @Test
+    fun fetchStatusSharesStartupPrefetchRequest() = runTest {
+        val remoteSource = FakeAmSatRemoteSource(responseDelayMillis = 50)
+        val repository = AmSatRepository(remoteSource)
+
+        val prefetch = async { repository.prefetchStatus() }
+        val pageFetch = async { repository.fetchStatus() }
+        prefetch.await()
+        val page = pageFetch.await()
+
+        assertSame(page, repository.getCachedStatus())
+        assertEquals(1, remoteSource.catalogRequests)
+        assertEquals(1, remoteSource.reportRequests)
+    }
+}
+
+private fun AmSatRepository.seedStatusCache(page: SatStatusPage) {
+    val cacheField = AmSatRepository::class.java.getDeclaredField("statusCache")
+    cacheField.isAccessible = true
+    cacheField.set(this, page)
+}
+
+private class FakeAmSatRemoteSource(private val responseDelayMillis: Long = 0L) : IRemoteSource {
+    var catalogRequests = 0
+    var reportRequests = 0
+
+    override suspend fun getFileStream(uri: String): InputStream? = null
+
+    override suspend fun getNetworkStream(url: String): NetworkResult = NetworkResult(404, null)
+
+    override suspend fun getAmSatCatalog(): String? {
+        if (responseDelayMillis > 0L) delay(responseDelayMillis)
+        catalogRequests += 1
+        return """{"data":[{"name":"AO-7"}]}"""
+    }
+
+    override suspend fun getAmSatReports(hours: Int, limit: Int): String? {
+        if (responseDelayMillis > 0L) delay(responseDelayMillis)
+        reportRequests += 1
+        return """{"data":[]}"""
+    }
+
+    override suspend fun submitAmSatReport(payloadJson: String): Pair<Int, String>? = null
+}

core/data/src/test/java/com/rtbishop/look4sat/core/data/repository/DatabaseRepoTest.kt

@@ -0,0 +1,306 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.model.DataSourcesSettings
+import com.rtbishop.look4sat.core.domain.model.DatabaseState
+import com.rtbishop.look4sat.core.domain.model.GridQso
+import com.rtbishop.look4sat.core.domain.model.OtherSettings
+import com.rtbishop.look4sat.core.domain.model.PassesSettings
+import com.rtbishop.look4sat.core.domain.model.RCSettings
+import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
+import com.rtbishop.look4sat.core.domain.model.SatItem
+import com.rtbishop.look4sat.core.domain.model.SatRadio
+import com.rtbishop.look4sat.core.domain.predict.GeoPos
+import com.rtbishop.look4sat.core.domain.predict.OrbitalData
+import com.rtbishop.look4sat.core.domain.predict.OrbitalObject
+import com.rtbishop.look4sat.core.domain.repository.ISettingsRepo
+import com.rtbishop.look4sat.core.domain.source.ILocalSource
+import com.rtbishop.look4sat.core.domain.source.IRemoteSource
+import com.rtbishop.look4sat.core.domain.source.NetworkResult
+import com.rtbishop.look4sat.core.domain.source.Sources
+import com.rtbishop.look4sat.core.domain.utility.DataParser
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import java.io.InputStream
+
+@OptIn(ExperimentalCoroutinesApi::class)
+class DatabaseRepoTest {
+
+    private val dispatcher = StandardTestDispatcher()
+    private val dataParser = DataParser(dispatcher)
+
+    @Test
+    fun `manual satellite import parses csv stream from content uri`() = runTest(dispatcher) {
+        val uri = "content://look4sat/import/satellites"
+        val localSource = FakeLocalSource()
+        val remoteSource = FakeRemoteSource().apply {
+            fileStreams[uri] = { validCsvStream() }
+        }
+        val settingsRepo = FakeSettingsRepo()
+        val repository = DatabaseRepo(dispatcher, dataParser, localSource, remoteSource, settingsRepo)
+
+        repository.updateTLEFromFile(uri)
+
+        assertEquals(1, localSource.insertedEntries.size)
+        assertEquals(25544, localSource.insertedEntries.first().catnum)
+        assertEquals(listOf(25544), settingsRepo.satelliteTypeIdsByType["Other"])
+        assertTrue(settingsRepo.databaseState.value.numberOfSatellites > 0)
+    }
+
+    @Test
+    fun `manual satellite import keeps tle support`() = runTest(dispatcher) {
+        val uri = "content://look4sat/import/legacy"
+        val localSource = FakeLocalSource()
+        val remoteSource = FakeRemoteSource().apply {
+            fileStreams[uri] = { validTleStream() }
+        }
+        val settingsRepo = FakeSettingsRepo()
+        val repository = DatabaseRepo(dispatcher, dataParser, localSource, remoteSource, settingsRepo)
+
+        repository.updateTLEFromFile(uri)
+
+        assertEquals(1, localSource.insertedEntries.size)
+        assertEquals(25544, localSource.insertedEntries.first().catnum)
+    }
+
+    @Test
+    fun `custom data source imports omm csv from web`() = runTest(dispatcher) {
+        val customCsvUrl = "https://example.com/custom-omm.csv"
+        val localSource = FakeLocalSource()
+        val remoteSource = FakeRemoteSource().apply {
+            networkStreams[customCsvUrl] = { validCsvStream() }
+        }
+        val settingsRepo = FakeSettingsRepo(
+            dataSources = DataSourcesSettings(
+                satelliteUrls = listOf(customCsvUrl),
+                transceiversUrls = emptyList()
+            )
+        )
+        val repository = DatabaseRepo(dispatcher, dataParser, localSource, remoteSource, settingsRepo)
+
+        repository.updateFromRemote()
+
+        assertTrue(localSource.insertedEntries.any { it.catnum == 25544 })
+        assertEquals(listOf(25544), settingsRepo.satelliteTypeIdsByType["Other"])
+    }
+
+    @Test
+    fun `remote update imports satellites from real SatNOGS TLE source`() = runTest(dispatcher) {
+        val satnogsUrl = Sources.satelliteDataUrls.getValue("SatNOGS")
+        val localSource = FakeLocalSource()
+        val remoteSource = FakeRemoteSource().apply {
+            networkStreams[satnogsUrl] = { jamxTleStream() }
+        }
+        val settingsRepo = FakeSettingsRepo(
+            dataSources = DataSourcesSettings(
+                satelliteUrls = listOf(satnogsUrl),
+                transceiversUrls = emptyList()
+            )
+        )
+        val repository = DatabaseRepo(dispatcher, dataParser, localSource, remoteSource, settingsRepo)
+
+        repository.updateFromRemote()
+
+        assertTrue(localSource.insertedEntries.any { it.name == "JAMX-0825b" && it.catnum == 98248 })
+        assertEquals(listOf(98248), settingsRepo.satelliteTypeIdsByType["SatNOGS"])
+    }
+
+    private fun validCsvStream(): InputStream = """
+        OBJECT_NAME,OBJECT_ID,EPOCH,MEAN_MOTION,ECCENTRICITY,INCLINATION,RA_OF_ASC_NODE,ARG_OF_PERICENTER,MEAN_ANOMALY,EPHEMERIS_TYPE,CLASSIFICATION_TYPE,NORAD_CAT_ID,ELEMENT_SET_NO,REV_AT_EPOCH,BSTAR,MEAN_MOTION_DOT,MEAN_MOTION_DDOT
+        ISS (ZARYA),1998-067A,2021-11-16T12:28:09.322176,15.48582035,.0004694,51.6447,309.4881,203.6966,299.8876,0,U,25544,999,31220,.31985E-4,.1288E-4,0
+    """.trimIndent().byteInputStream()
+
+    private fun validTleStream(): InputStream = """
+        ISS (ZARYA)
+        1 25544U 98067A   21320.51955234  .00001288  00000+0  31985-4 0  9990
+        2 25544  51.6447 309.4881 0004694 203.6966 299.8876 15.48582035312205
+    """.trimIndent().byteInputStream()
+
+    private fun jamxTleStream(): InputStream = """
+        JAMX-0825b
+        1 98248U          26237.16675926  .00015724  00000-0  97477-3 0 00013
+        2 98248 097.5373 310.9694 0011309 278.1232 340.7230 15.09766181000012
+    """.trimIndent().byteInputStream()
+}
+
+private class FakeRemoteSource : IRemoteSource {
+    val fileStreams: MutableMap<String, () -> InputStream> = mutableMapOf()
+    val networkStreams: MutableMap<String, () -> InputStream> = mutableMapOf()
+
+    override suspend fun getFileStream(uri: String): InputStream? = fileStreams[uri]?.invoke()
+
+    override suspend fun getNetworkStream(url: String): NetworkResult =
+        networkStreams[url]?.let { NetworkResult(200, it()) } ?: NetworkResult(404, null)
+
+    override suspend fun getAmSatCatalog(): String? = null
+
+    override suspend fun getAmSatReports(hours: Int, limit: Int): String? = null
+
+    override suspend fun submitAmSatReport(payloadJson: String): Pair<Int, String>? = null
+}
+
+private class FakeLocalSource : ILocalSource {
+    val insertedEntries = mutableListOf<OrbitalData>()
+    private val insertedRadios = mutableListOf<SatRadio>()
+
+    override suspend fun getEntriesTotal(): Int = insertedEntries.size
+
+    override suspend fun getEntriesList(): List<SatItem> = emptyList()
+
+    override suspend fun getEntriesWithIds(ids: List<Int>): List<OrbitalObject> = emptyList()
+
+    override suspend fun insertEntries(entries: List<OrbitalData>) {
+        insertedEntries += entries
+    }
+
+    override suspend fun deleteEntries() {
+        insertedEntries.clear()
+    }
+
+    override suspend fun getIdsWithModes(modes: List<String>): List<Int> = emptyList()
+
+    override suspend fun getRadiosTotal(): Int = insertedRadios.size
+
+    override suspend fun getRadiosWithId(id: Int): List<SatRadio> = emptyList()
+
+    override suspend fun insertRadios(radios: List<SatRadio>) {
+        insertedRadios += radios
+    }
+
+    override suspend fun deleteRadios() {
+        insertedRadios.clear()
+    }
+}
+
+private class FakeSettingsRepo(dataSources: DataSourcesSettings = defaultDataSourcesSettings()) : ISettingsRepo {
+
+    override val appVersionName: String = "test"
+
+    override val selectedIds: StateFlow<List<Int>> = MutableStateFlow(emptyList())
+
+    override val selectedTypes: StateFlow<List<String>> = MutableStateFlow(emptyList())
+
+    override val passesSettings: StateFlow<PassesSettings> = MutableStateFlow(
+        PassesSettings(hoursAhead = 24, minElevation = 0.0, selectedModes = emptyList())
+    )
+
+    override val stationPosition: StateFlow<GeoPos> = MutableStateFlow(GeoPos(0.0, 0.0))
+
+    override val databaseState: MutableStateFlow<DatabaseState> = MutableStateFlow(DatabaseState(0, 0, 0L))
+
+    override val rcSettings: StateFlow<RCSettings> = MutableStateFlow(
+        RCSettings(false, "", "", "", false, "", "", "", 0L, false, "", "", "", false, "", "")
+    )
+
+    override val otherSettings: StateFlow<OtherSettings> = MutableStateFlow(
+        OtherSettings(
+            false, false, false, false, false, false, false,
+            shouldSeeWarning = false, shouldSeeWhatsNew = false
+        )
+    )
+
+    override val dataSourcesSettings: MutableStateFlow<DataSourcesSettings> = MutableStateFlow(dataSources)
+
+    override val radioControlSettings: StateFlow<RadioControlSettings> = MutableStateFlow(
+        RadioControlSettings(false, RadioControlSettings.MODEL_YAESU_FT817, "", "", "", "", 9600)
+    )
+
+    val satelliteTypeIdsByType = mutableMapOf<String, List<Int>>()
+
+    override fun setSelectedIds(ids: List<Int>) = Unit
+
+    override fun setSelectedTypes(types: List<String>) = Unit
+
+    override fun setPassesSettings(settings: PassesSettings) = Unit
+
+    override fun setStationPosition(latitude: Double, longitude: Double, altitude: Double): Boolean = true
+
+    override fun setStationPosition(): Boolean = true
+
+    override fun setStationPosition(locator: String): Boolean = true
+
+    override fun getSatelliteTypesIds(types: List<String>): List<Int> = emptyList()
+
+    override fun setSatelliteTypeIds(type: String, ids: List<Int>) {
+        satelliteTypeIdsByType[type] = ids
+    }
+
+    override fun updateDatabaseState(state: DatabaseState) {
+        databaseState.value = state
+    }
+
+    override fun updateRCSettings(settings: RCSettings) = Unit
+
+    override fun updateOtherSettings(transform: (OtherSettings) -> OtherSettings) = Unit
+
+    override fun updateDataSourcesSettings(settings: DataSourcesSettings) {
+        dataSourcesSettings.value = settings
+    }
+
+    override val dataSourcesStatus: StateFlow<Map<String, Int>> = MutableStateFlow(emptyMap())
+
+    override fun updateDataSourcesStatus(status: Map<String, Int>) {
+        (dataSourcesStatus as? MutableStateFlow)?.value = status
+    }
+
+    override fun updateRadioControlSettings(settings: RadioControlSettings) = Unit
+
+    override fun getSatelliteOffset(catnum: Int): String = ""
+
+    override fun setSatelliteOffset(catnum: Int, offset: String) = Unit
+
+    override fun getAmSatCallsign(): String = ""
+
+    override fun setAmSatCallsign(callsign: String) = Unit
+
+    override val wavelogSettings: StateFlow<com.rtbishop.look4sat.core.domain.model.WavelogSettings> =
+        MutableStateFlow(com.rtbishop.look4sat.core.domain.model.WavelogSettings())
+
+    override fun updateWavelogSettings(settings: com.rtbishop.look4sat.core.domain.model.WavelogSettings) = Unit
+
+    override fun getWorkedGrids(): Set<String> = emptySet()
+
+    private val workedGrids = MutableStateFlow(emptySet<String>())
+
+    override fun setWorkedGrids(grids: Set<String>) {
+        workedGrids.value = grids
+    }
+
+    override val lotwSettings: StateFlow<com.rtbishop.look4sat.core.domain.model.LoTWSettings> =
+        MutableStateFlow(com.rtbishop.look4sat.core.domain.model.LoTWSettings())
+
+    override fun updateLoTWSettings(settings: com.rtbishop.look4sat.core.domain.model.LoTWSettings) = Unit
+
+    override fun getWorkedGridQsos(): Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>> = emptyMap()
+
+    override fun setWorkedGridQsos(qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>) = Unit
+}
+
+private fun defaultDataSourcesSettings(): DataSourcesSettings {
+    return DataSourcesSettings(
+        satelliteUrls = emptyList(),
+        transceiversUrls = emptyList()
+    )
+}

core/data/src/test/java/com/rtbishop/look4sat/core/data/repository/LoTWRepositoryTest.kt

@@ -0,0 +1,216 @@
+package com.rtbishop.look4sat.core.data.repository
+
+import com.rtbishop.look4sat.core.domain.repository.LoTWResult
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Test
+
+class LoTWRepositoryTest {
+
+    private val repo = LoTWRepository()
+
+    private fun report(vararg records: String): String =
+        buildString {
+            append("<ADIF_VERS:5>3.1.4\n")
+            append("<PROGRAMID:8>look4sat\n")
+            append("<eoh>\n")
+            records.forEach { append(it).append("\n") }
+        }
+
+    @Test
+    fun parseRejectsBodyWithoutEoh() {
+        assertNull(repo.parseConfirmedGrids("<HTML>Username/password incorrect</HTML>"))
+    }
+
+    @Test
+    fun parseCollectsOnlySatelliteGrids() {
+        // Satellite QSO: PROP_MODE SAT, confirmed, opponent grid.
+        val satQso = "<CALL:6>BA7OPF\n" +
+            "<QSO_DATE:8>20260820\n" +
+            "<PROP_MODE:3>SAT\n" +
+            "<SAT_NAME:5>FO-29\n" +
+            "<GRIDSQUARE:4>NL47\n" +
+            "<EOR>\n"
+        // Ground QSO: same grid but no PROP_MODE -> must be excluded.
+        val groundQso = "<CALL:6>BA7OPF\n" +
+            "<QSO_DATE:8>20260821\n" +
+            "<GRIDSQUARE:4>NL47\n" +
+            "<EOR>\n"
+        val result = repo.parseConfirmedGrids(report(satQso, groundQso))
+        assertEquals(setOf("NL47"), result)
+    }
+
+    @Test
+    fun parseSupportsVuccGridPairsAndSixCharGrids() {
+        val satQso = "<PROP_MODE:3>SAT\n" +
+            "<SAT_NAME:5>SO-50\n" +
+            "<GRIDSQUARE:6>OM60IL\n" +
+            "<VUCC_GRIDS:11>EN52en,EN53fa\n" +
+            "<EOR>\n"
+        val result = repo.parseConfirmedGrids(report(satQso))
+        assertEquals(setOf("OM60", "EN52", "EN53"), result)
+    }
+
+    @Test
+    fun parsePropModeDoesNotLeakAcrossRecords() {
+        // PROP_MODE SAT record first, then a ground QSO with a grid — the second
+        // record must not inherit the satellite flag after its own <EOR>.
+        val satQso = "<PROP_MODE:3>SAT\n<GRIDSQUARE:4>OL62\n<EOR>\n"
+        val groundQso = "<GRIDSQUARE:4>PM00\n<EOR>\n"
+        val result = repo.parseConfirmedGrids(report(satQso, groundQso))
+        assertEquals(setOf("OL62"), result)
+    }
+
+    @Test
+    fun parseReturnsEmptySetForReportWithoutGrids() {
+        val satQso = "<PROP_MODE:3>SAT\n<SAT_NAME:5>AO-07\n<EOR>\n"
+        assertEquals(emptySet<String>(), repo.parseConfirmedGrids(report(satQso)))
+    }
+
+    // region parseConfirmedGridQsos
+
+    private val satQsoFull = "<CALL:5>A50QO\n" +
+        "<QSO_DATE:8>20260820\n" +
+        "<TIME_ON:6>113045\n" +
+        "<PROP_MODE:3>SAT\n" +
+        "<SAT_NAME:5>FO-29\n" +
+        "<MODE:2>CW\n" +
+        "<BAND:3>70CM\n" +
+        "<BAND_RX:3>2M\n" +
+        "<GRIDSQUARE:4>NL47\n" +
+        "<EOR>\n"
+
+    @Test
+    fun parseQsosExtractsSatelliteDetail() {
+        val result = repo.parseConfirmedGridQsos(report(satQsoFull))!!
+        val qsos = result["NL47"]!!
+        assertEquals(1, qsos.size)
+        val qso = qsos[0]
+        assertEquals("A50QO", qso.call)
+        assertEquals("FO-29", qso.satName)
+        assertEquals("CW", qso.mode)
+        assertEquals("2M", qso.bandUp)
+        assertEquals("70CM", qso.bandDown)
+        assertEquals("V/U", qso.bandLabel)
+        assertEquals(2026, java.time.Instant.ofEpochMilli(qso.epochMs).atZone(java.time.ZoneOffset.UTC).year)
+    }
+
+    @Test
+    fun parseQsosExcludesGroundQsos() {
+        val groundQso = "<CALL:6>BA7OPF\n<QSO_DATE:8>20260821\n<GRIDSQUARE:4>NL47\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(satQsoFull, groundQso))!!
+        assertEquals(1, result["NL47"]!!.size)
+    }
+
+    @Test
+    fun parseQsosVuccPairFeedsBothGrids() {
+        val qso = "<PROP_MODE:3>SAT\n<SAT_NAME:5>SO-50\n" +
+            "<QSO_DATE:8>20260819\n<TIME_ON:4>1231\n" +
+            "<VUCC_GRIDS:11>EN52en,EN53fa\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(qso))!!
+        assertEquals(setOf("EN52", "EN53"), result.keys)
+        assertEquals(result["EN52"]!!.first(), result["EN53"]!!.first())
+    }
+
+    @Test
+    fun parseQsosVuccQuadrupleFeedsAllFourGrids() {
+        // VUCC allows up to four grids in one contact.
+        val qso = "<PROP_MODE:3>SAT\n<SAT_NAME:5>SO-50\n" +
+            "<QSO_DATE:8>20260819\n<TIME_ON:4>1231\n" +
+            "<VUCC_GRIDS:23>EN52en,EN53fa,EN42gj,EN43kh\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(qso))!!
+        assertEquals(setOf("EN52", "EN53", "EN42", "EN43"), result.keys)
+        result.values.forEach { assertEquals(1, it.size) }
+    }
+
+    @Test
+    fun parseQsosRejectsBodyWithoutEoh() {
+        assertNull(repo.parseConfirmedGridQsos("<HTML>Username/password incorrect</HTML>"))
+    }
+
+    // endregion
+
+    // region failure classification (fetchReportBody -> LoTWResult mapping)
+
+    @Test
+    fun failureClassificationMapsEachException() {
+        // LoTWRepository.toResult() must keep each failure cause distinct so
+        // the UI can show a specific message per cause.
+        assertEquals(
+            LoTWResult.BadCredentials,
+            repo.toResult(LoTWRepository.CredentialsException())
+        )
+        assertEquals(
+            LoTWResult.RateLimited,
+            repo.toResult(LoTWRepository.RateLimitException())
+        )
+        assertEquals(
+            LoTWResult.Timeout,
+            repo.toResult(LoTWRepository.TimeoutException("read timed out"))
+        )
+        val net = repo.toResult(java.io.IOException("HTTP 500"))
+        assertEquals(LoTWResult.NetworkError("HTTP 500"), net)
+    }
+
+
+    @Test
+    fun parseQsosExtractsAwardFields() {
+        // Award statistics rely on the DXCC/CQZ/STATE fields coming straight
+        // from LoTW's qso_qsldetail report (STATE depends on DXCC). LoTW
+        // writes STATE as "CODE // NAME" (verified with a real report 2026-09);
+        // the parser must strip the name suffix and keep the bare code.
+        val qso = "<CALL:5>BG7XYZ\n" +
+            "<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>FO-29\n<MODE:2>CW\n" +
+            "<DXCC:3>318\n<COUNTRY:5>CHINA\n<CQZ:2>24\n<STATE:13>GD // Guangdong\n" +
+            "<GRIDSQUARE:4>OL62\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(qso))!!
+        val parsed = result["OL62"]!!.first()
+        assertEquals(318, parsed.dxcc)
+        assertEquals("CHINA", parsed.country)
+        assertEquals(24, parsed.cqz)
+        assertEquals("GD", parsed.state)
+    }
+
+    @Test
+    fun parseQsosStripsStateNameSuffixForAllEntities() {
+        // Japan prefecture: "34 // Tottori-ken" -> "34" (WAJA matching needs
+        // the 2-digit code). US states also arrive as "CODE // Name".
+        val jp = "<CALL:5>JH0ABC\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n<DXCC:3>339\n<COUNTRY:7>JAPAN\n" +
+            "<STATE:18>34 // Tottori-ken\n<GRIDSQUARE:4>PM95\n<EOR>\n"
+        val us = "<CALL:5>K1ABC\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>AO-07\n<DXCC:3>291\n<COUNTRY:12>UNITED STATES\n" +
+            "<STATE:22>CA // California\n<GRIDSQUARE:4>EM40\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(jp, us))!!
+        assertEquals("34", result["PM95"]!!.first().state)
+        assertEquals("CA", result["EM40"]!!.first().state)
+    }
+
+    @Test
+    fun parseQsosLeavesAwardFieldsNullWhenAbsent() {
+        val qso = "<CALL:5>JH0ABC\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n<GRIDSQUARE:4>PM95\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(qso))!!
+        val parsed = result["PM95"]!!.first()
+        assertNull(parsed.dxcc)
+        assertNull(parsed.country)
+        assertNull(parsed.cqz)
+        assertNull(parsed.state)
+    }
+
+    @Test
+    fun parseQsosAwardFieldsDoNotLeakAcrossRecords() {
+        val withFields = "<CALL:5>BG7AAA\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>FO-29\n<DXCC:3>318\n<CQZ:2>24\n<STATE:2>GD\n" +
+            "<GRIDSQUARE:4>OL62\n<EOR>\n"
+        val withoutFields = "<CALL:5>JH0BBB\n<QSO_DATE:8>20260821\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n<GRIDSQUARE:4>PM95\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(withFields, withoutFields))!!
+        assertNull(result["PM95"]!!.first().dxcc)
+        assertNull(result["PM95"]!!.first().cqz)
+        assertNull(result["PM95"]!!.first().state)
+    }
+
+    // endregion
+}

core/domain/build.gradle.kts

@@ -1,3 +1,3 @@
 plugins {
-    alias(libs.plugins.convention.kotlinLibraryPlugin)
+    alias(libs.plugins.convention.coreDomainPlugin)
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwBayesianDecoder.kt

@@ -0,0 +1,154 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+/**
+ * Bayesian Morse timing decoder.
+ * Replaces hard thresholds with probability-based decision making.
+ *
+ * Inspired by VE3NEA's CW Skimmer approach:
+ * "Instead of making a hard decision at every input sample whether the signal
+ * is present or not, compute the probability that the signal is present."
+ *
+ * Uses Gaussian probability density centered on expected durations:
+ *   P(dit | duration) = exp(-(duration - dotMs)^2 / (2 * variance^2))
+ *   P(dash | duration) = exp(-(duration - 3*dotMs)^2 / (2 * variance^2))
+ */
+internal class CwBayesianDecoder {
+
+    // Morse timing parameters
+    private var dotDurationMs = 60f // initial 20 WPM
+    private var speedWpm = 20f
+
+    // Current symbol being accumulated
+    private var currentSymbol = StringBuilder()
+    private var textBuffer = StringBuilder()
+
+    // Recent dit lengths for speed estimation
+    private val recentDits = mutableListOf<Float>()
+
+    // Output
+    private var _decodedText = ""
+    val decodedText: String get() = _decodedText
+
+    /** Gaussian probability. */
+    private fun gaussianProb(durationMs: Float, expectedMs: Float, varianceMs: Float): Float {
+        if (varianceMs <= 0f) return 0f
+        val diff = durationMs - expectedMs
+        return kotlin.math.exp(-(diff * diff) / (2 * varianceMs * varianceMs))
+    }
+
+    /** Process a tone duration. Returns the symbol type with highest probability. */
+    fun processTone(durationMs: Float): ToneResult {
+        val ditProb = gaussianProb(durationMs, dotDurationMs, dotDurationMs * 0.4f)
+        val dashProb = gaussianProb(durationMs, dotDurationMs * 3f, dotDurationMs * 0.6f)
+
+        return if (ditProb > dashProb && ditProb > 0.05f) {
+            currentSymbol.append('0')
+            recentDits.add(durationMs)
+            updateSpeed()
+            ToneResult('0', ditProb)
+        } else if (dashProb > 0.05f) {
+            currentSymbol.append('1')
+            ToneResult('1', dashProb)
+        } else {
+            ToneResult(null, 0f)
+        }
+    }
+
+    /** Process a gap duration. Returns decoded character or null. */
+    fun processGap(durationMs: Float): Char? {
+        if (currentSymbol.isEmpty()) {
+            val wordProb = gaussianProb(durationMs, dotDurationMs * 7f, dotDurationMs * 1.2f)
+            if (wordProb > 0.2f) {
+                textBuffer.append(' ')
+                _decodedText = textBuffer.toString()
+                return ' '
+            }
+            return null
+        }
+
+        val interCharProb = gaussianProb(durationMs, dotDurationMs * 3f, dotDurationMs * 0.6f)
+        val wordProb = gaussianProb(durationMs, dotDurationMs * 7f, dotDurationMs * 1.2f)
+
+        if (wordProb > interCharProb && wordProb > 0.2f) {
+            val char = flushSymbol()
+            textBuffer.append(' ')
+            _decodedText = textBuffer.toString()
+            return char
+        }
+        if (interCharProb > 0.15f) {
+            val char = flushSymbol()
+            _decodedText = textBuffer.toString()
+            return char
+        }
+        return null
+    }
+
+    private fun flushSymbol(): Char? {
+        if (currentSymbol.isEmpty()) return null
+        val morse = currentSymbol.toString()
+        currentSymbol.clear()
+        val char = morseToChar(morse)
+        if (char != null) textBuffer.append(char)
+        return char
+    }
+
+    private fun updateSpeed() {
+        if (recentDits.size < 3) return
+        val sorted = recentDits.sorted()
+        val median = sorted[sorted.size / 2]
+        if (median > 0f) {
+            dotDurationMs = dotDurationMs * 0.7f + median * 0.3f
+            val wpm = 60.0f / (50.0f * dotDurationMs / 1000.0f)
+            if (wpm in 5f..55f) speedWpm = wpm
+        }
+    }
+
+    fun getSpeed(): Float = speedWpm
+
+    fun reset() {
+        dotDurationMs = 60f
+        speedWpm = 20f
+        recentDits.clear()
+        currentSymbol.clear()
+        textBuffer.clear()
+        _decodedText = ""
+    }
+
+    companion object {
+        private val MORSE_TABLE = mapOf(
+            "01" to 'A', "1000" to 'B', "1010" to 'C', "100" to 'D', "0" to 'E',
+            "0010" to 'F', "110" to 'G', "0000" to 'H', "00" to 'I', "0111" to 'J',
+            "101" to 'K', "0100" to 'L', "11" to 'M', "10" to 'N', "111" to 'O',
+            "0110" to 'P', "1101" to 'Q', "010" to 'R', "000" to 'S', "1" to 'T',
+            "001" to 'U', "0001" to 'V', "011" to 'W', "1001" to 'X', "1011" to 'Y',
+            "1100" to 'Z', "01111" to '1', "00111" to '2', "00011" to '3',
+            "00001" to '4', "00000" to '5', "10000" to '6', "11000" to '7',
+            "11100" to '8', "11110" to '9', "11111" to '0',
+            "010101" to '.', "110011" to ',', "001100" to '?', "011110" to '\'',
+            "101011" to '!', "10010" to '/', "10110" to '(', "101101" to ')',
+            "01000" to '&', "111000" to ':', "101010" to ';', "10001" to '=',
+            "01010" to '+', "100001" to '-', "001101" to '_', "010010" to '"',
+            "0001001" to '$', "011010" to '@'
+        )
+        fun morseToChar(morse: String): Char? = MORSE_TABLE[morse]
+    }
+}
+
+data class ToneResult(val symbol: Char?, val probability: Float)

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwChannelTracker.kt

@@ -0,0 +1,114 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+/**
+ * Multi-channel CW signal tracker.
+ * Monitors the spectrogram for active frequency bins and extracts
+ * energy envelopes for each detected signal.
+ *
+ * Inspired by CW Skimmer's multi-channel approach:
+ * tracks all active signals in the passband simultaneously,
+ * selects the best one for decoded output.
+ */
+internal class CwChannelTracker(
+    private val spectrogram: CwSpectrogram,
+    private val maxChannels: Int = 3
+) {
+    data class Channel(
+        val bin: Int,
+        val frequency: Float,
+        var active: Boolean = false,
+        var energy: Float = 0f,
+        val history: MutableList<Float> = mutableListOf(),
+        var confidence: Float = 0f
+    )
+
+    private val channels = Array(maxChannels) { Channel(0, 0f) }
+
+    /** Scan the current spectrogram column and update channel tracking. */
+    fun update(): List<Channel> {
+        val col = spectrogram.getCurrentColumn()
+        val peaks = findPeaks(col, threshold = 0.3f, minDistance = 2)
+
+        // Update existing channels
+        for (ch in channels) {
+            if (ch.active) {
+                if (peaks.contains(ch.bin)) {
+                    ch.energy = col[ch.bin]
+                    ch.history.add(ch.energy)
+                    if (ch.history.size > 40) ch.history.removeAt(0)
+                    ch.confidence = computeConfidence(ch.history)
+                } else {
+                    // Signal lost — decay confidence
+                    ch.history.add(0f)
+                    if (ch.history.size > 40) ch.history.removeAt(0)
+                    ch.confidence *= 0.9f
+                    if (ch.confidence < 0.1f) ch.active = false
+                }
+            }
+        }
+
+        // Assign new peaks to inactive channels
+        var peakIdx = 0
+        for (ch in channels) {
+            if (!ch.active && peakIdx < peaks.size) {
+                val bin = peaks[peakIdx]
+                val freq = spectrogram.binToFreq(bin)
+                // Re-initialize channel
+                channels[peakIdx] = Channel(bin, freq, true, col[bin], mutableListOf(), 0.5f)
+                peakIdx++
+            }
+        }
+
+        return channels.filter { it.active }
+    }
+
+    /** Find peak bins in the spectrum. */
+    private fun findPeaks(spectrum: FloatArray, threshold: Float, minDistance: Int): List<Int> {
+        val peaks = mutableListOf<Int>()
+        for (i in 1 until spectrum.size - 1) {
+            if (spectrum[i] > spectrum[i - 1] && spectrum[i] > spectrum[i + 1] && spectrum[i] > threshold) {
+                if (peaks.isEmpty() || i - peaks.last() >= minDistance) {
+                    peaks.add(i)
+                }
+            }
+        }
+        return peaks.sortedByDescending { spectrum[it] }
+    }
+
+    /** Compute confidence from energy history. Lower variance = higher confidence. */
+    private fun computeConfidence(history: List<Float>): Float {
+        if (history.size < 10) return 0.3f
+        val recent = history.takeLast(10)
+        val mean = recent.average().toFloat()
+        val variance = recent.map { (it - mean) * (it - mean) }.average().toFloat()
+        return if (mean > 0f) (mean / (mean + variance + 0.1f)).coerceIn(0f, 1f) else 0f
+    }
+
+    /** Get the channel with highest confidence. */
+    fun getBestChannel(): Channel? {
+        return channels.filter { it.active }.maxByOrNull { it.confidence }
+    }
+
+    fun reset() {
+        for (i in channels.indices) {
+            channels[i] = Channel(0, 0f)
+        }
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwDecoder.kt

@@ -0,0 +1,165 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+
+/**
+ * CW (Morse code) decoder v3 — Spectrogram-based multi-channel Bayesian decoder.
+ *
+ * Architecture inspired by Morse Expert / CW Skimmer (VE3NEA):
+ *   1. FFT spectrogram creates a frequency×time matrix
+ *   2. Multi-channel peak detector finds all active signals
+ *   3. Per-channel energy envelope extraction
+ *   4. Bayesian probability for symbol timing (Gaussian likelihood)
+ *   5. Best channel selected for output
+ *
+ * Timing analysis is performed per spectrogram column (hop).
+ * Each column represents hopSize/sampleRate seconds of audio.
+ */
+class CwDecoder(
+    val sampleRate: Int = 8000,
+    cwToneFreq: Float = -1f // ignored in v3 (auto-detect via spectrogram)
+) {
+    companion object {
+        private const val FFT_SIZE = 256
+        private const val HOP_SIZE = 64
+    }
+
+    private val spectrogram = CwSpectrogram(
+        fftSize = FFT_SIZE,
+        hopSize = HOP_SIZE,
+        sampleRate = sampleRate,
+        minBin = 6,
+        maxBin = 38,
+        historyCols = 40
+    )
+    private val channelTracker = CwChannelTracker(spectrogram, maxChannels = 3)
+    private val bayesianDecoder = CwBayesianDecoder()
+
+    // Timing state per channel
+    private data class ChannelTiming(
+        var isSignal: Boolean = false,
+        var toneTicks: Int = 0,
+        var gapTicks: Int = 0
+    )
+    private val timingStates = Array(3) { ChannelTiming() }
+
+    // Time per spectrogram column in milliseconds
+    private val tickMs = 1000f * HOP_SIZE / sampleRate
+
+    // Output flows
+    private val _decodedTextFlow = MutableStateFlow("")
+    val decodedTextFlow: StateFlow<String> = _decodedTextFlow
+
+    private val _signalStrength = MutableStateFlow(0f)
+    val signalStrength: StateFlow<Float> = _signalStrength
+
+    private val _estimatedPitch = MutableStateFlow<Float?>(null)
+    val estimatedPitch: StateFlow<Float?> = _estimatedPitch
+
+    private val _estimatedSpeed = MutableStateFlow<Float?>(null)
+    val estimatedSpeed: StateFlow<Float?> = _estimatedSpeed
+
+    private var frameCount = 0
+
+    init {
+        if (cwToneFreq > 0f) {
+            _estimatedPitch.value = cwToneFreq
+        }
+    }
+
+    fun processBuffer(buffer: FloatArray) {
+        // 1. Feed samples to spectrogram
+        spectrogram.addSamples(buffer)
+
+        // 2. Get number of new columns generated
+        val newCols = spectrogram.getNewColumns()
+        if (newCols == 0) return
+
+        // 3. Update channel tracker (uses latest column for peak detection)
+        val activeChannels = channelTracker.update()
+
+        // 4. Process each new column for timing analysis
+        //    Columns are indexed 0..historyCols-1, where historyCols-1 is the newest
+        val baseIdx = (spectrogram.historyCols - newCols).coerceAtLeast(0)
+        for (colOffset in 0 until newCols) {
+            val col = spectrogram.getColumn(baseIdx + colOffset)
+
+            for ((idx, channel) in activeChannels.withIndex()) {
+                if (idx >= timingStates.size) break
+                val state = timingStates[idx]
+                val energy = if (channel.bin in col.indices) col[channel.bin] else 0f
+
+                // Adaptive threshold
+                val threshold = 0.3f + (energy - 0.3f) * 0.3f
+
+                if (energy > threshold) {
+                    if (!state.isSignal) {
+                        if (state.gapTicks > 0) {
+                            val gapMs = state.gapTicks * tickMs
+                            bayesianDecoder.processGap(gapMs)
+                        }
+                        state.gapTicks = 0
+                        state.isSignal = true
+                    }
+                    state.toneTicks++
+                } else {
+                    if (state.isSignal) {
+                        if (state.toneTicks > 0) {
+                            val toneMs = state.toneTicks * tickMs
+                            bayesianDecoder.processTone(toneMs)
+                        }
+                        state.toneTicks = 0
+                        state.isSignal = false
+                    }
+                    state.gapTicks++
+                }
+            }
+        }
+
+        // 5. Update outputs
+        frameCount++
+        if (frameCount % 5 == 0) {
+            val bestChannel = channelTracker.getBestChannel()
+            if (bestChannel != null) {
+                _estimatedPitch.value = bestChannel.frequency
+                _signalStrength.value = bestChannel.confidence
+                _estimatedSpeed.value = bayesianDecoder.getSpeed()
+            }
+            _decodedTextFlow.value = bayesianDecoder.decodedText
+        }
+    }
+
+    fun resetDecoder() {
+        spectrogram.reset()
+        channelTracker.reset()
+        bayesianDecoder.reset()
+        for (state in timingStates) {
+            state.isSignal = false
+            state.toneTicks = 0
+            state.gapTicks = 0
+        }
+        frameCount = 0
+        _decodedTextFlow.value = ""
+        _signalStrength.value = 0f
+        _estimatedPitch.value = null
+        _estimatedSpeed.value = null
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwDsp.kt

@@ -0,0 +1,102 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+import kotlin.math.PI
+import kotlin.math.cos
+import kotlin.math.sin
+import kotlin.math.sqrt
+
+/**
+ * DSP utilities for CW (Morse code) decoding.
+ * Pure Kotlin, no NDK required.
+ */
+internal object CwDsp {
+
+    /**
+     * Design a simple bandpass FIR filter coefficients using windowed sinc method.
+     * @param lowCutoff  lower cutoff frequency (Hz) as fraction of sampleRate
+     * @param highCutoff upper cutoff frequency (Hz) as fraction of sampleRate
+     * @param taps       filter length (must be odd)
+     */
+    fun bandpassFir(lowCutoff: Double, highCutoff: Double, taps: Int): FloatArray {
+        val n = if (taps % 2 == 0) taps + 1 else taps
+        val half = n / 2
+        val coeffs = FloatArray(n)
+        for (i in 0 until n) {
+            val idx = i - half
+            if (idx == 0) {
+                coeffs[i] = (2.0 * (highCutoff - lowCutoff)).toFloat()
+            } else {
+                val x = PI * idx
+                coeffs[i] = ((sin(2 * highCutoff * x) - sin(2 * lowCutoff * x)) / x).toFloat()
+            }
+            // Hamming window
+            coeffs[i] = (coeffs[i] * (0.54 - 0.46 * cos(2 * PI * i / (n - 1)))).toFloat()
+        }
+        // Normalize
+        val sum = coeffs.sum()
+        if (sum != 0f) for (i in 0 until n) coeffs[i] /= sum
+        return coeffs
+    }
+
+    /** Apply FIR filter to a buffer. */
+    fun applyFir(buffer: FloatArray, coeffs: FloatArray): FloatArray {
+        val out = FloatArray(buffer.size)
+        for (i in buffer.indices) {
+            var sum = 0f
+            for (j in coeffs.indices) {
+                val idx = i - j
+                if (idx >= 0) sum += buffer[idx] * coeffs[j]
+            }
+            out[i] = sum
+        }
+        return out
+    }
+
+    /** Simple envelope detector: abs + low-pass smoothing. */
+    fun envelope(signal: FloatArray, alpha: Float = 0.1f): FloatArray {
+        val env = FloatArray(signal.size)
+        var s = 0f
+        for (i in signal.indices) {
+            s = alpha * kotlin.math.abs(signal[i]) + (1 - alpha) * s
+            env[i] = s
+        }
+        return env
+    }
+
+    /** Estimate noise floor from envelope for adaptive thresholding. */
+    fun noiseFloor(env: FloatArray, fraction: Float = 0.3f): Float {
+        val sorted = env.sortedArray()
+        val median = sorted[sorted.size / 2]
+        return median + (sorted[sorted.size * 9 / 10] - median) * fraction
+    }
+
+    /** Simple Goertzel to detect a specific tone frequency. */
+    fun goertzel(buffer: FloatArray, targetFreq: Float, sampleRate: Int): Float {
+        val omega = 2.0 * PI * targetFreq / sampleRate
+        val coeff = 2.0 * cos(omega)
+        var s0 = 0.0; var s1 = 0.0; var s2 = 0.0
+        for (sample in buffer) {
+            s0 = sample.toDouble() + coeff * s1 - s2
+            s2 = s1; s1 = s0
+        }
+        val power = s2 * s2 + s1 * s1 - coeff * s1 * s2
+        return sqrt(kotlin.math.abs(power)).toFloat()
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwFFT.kt

@@ -0,0 +1,87 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+import kotlin.math.cos
+import kotlin.math.sqrt
+
+/**
+ * Radix-2 FFT for real-valued input.
+ * Produces magnitude spectrum for the first N/2+1 bins.
+ * Used by CwSpectrogram for time-frequency analysis.
+ */
+internal class CwFFT(private val n: Int) {
+    init {
+        require(n > 0 && n and (n - 1) == 0) { "FFT size must be power of 2, got $n" }
+    }
+
+    private val cosTable = FloatArray(n / 2)
+    private val sinTable = FloatArray(n / 2)
+
+    init {
+        for (i in 0 until n / 2) {
+            val angle = -2.0 * kotlin.math.PI * i / n
+            cosTable[i] = cos(angle).toFloat()
+            sinTable[i] = kotlin.math.sin(angle).toFloat()
+        }
+    }
+
+    /** Compute magnitude spectrum for real input. Returns array of size n/2+1. */
+    fun magnitudeSpectrum(input: FloatArray): FloatArray {
+        require(input.size == n) { "Input size must be $n, got ${input.size}" }
+
+        val real = input.copyOf()
+        val imag = FloatArray(n)
+
+        // Bit-reversal permutation
+        var j = 0
+        for (i in 1 until n) {
+            var bit = n shr 1
+            while (j and bit != 0) { j = j xor bit; bit = bit shr 1 }
+            j = j xor bit
+            if (i < j) {
+                var tmp = real[i]; real[i] = real[j]; real[j] = tmp
+            }
+        }
+
+        // Radix-2 Cooley-Tukey FFT
+        var len = 2
+        while (len <= n) {
+            val half = len / 2
+            val step = n / len
+            for (i in 0 until n step len) {
+                for (k in 0 until half) {
+                    val tReal = real[i + k + half] * cosTable[k * step] - imag[i + k + half] * sinTable[k * step]
+                    val tImag = real[i + k + half] * sinTable[k * step] + imag[i + k + half] * cosTable[k * step]
+                    real[i + k + half] = real[i + k] - tReal
+                    imag[i + k + half] = imag[i + k] - tImag
+                    real[i + k] += tReal
+                    imag[i + k] += tImag
+                }
+            }
+            len = len shl 1
+        }
+
+        // Magnitude spectrum (first N/2+1 bins)
+        val mag = FloatArray(n / 2 + 1)
+        for (i in 0..n / 2) {
+            mag[i] = sqrt(real[i] * real[i] + imag[i] * imag[i]) / n
+        }
+        return mag
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwFilter.kt

@@ -0,0 +1,48 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+/**
+ * First-order IIR filters.
+ * Ported from ggmorse/src/filter.h
+ */
+internal class CwFilter {
+    private var z1 = 0f
+
+    companion object {
+        private const val PI_F = 3.141592653589793f
+    }
+
+    fun highPass(sample: Float, cutoffHz: Float, sampleRate: Float): Float {
+        val rc = 1.0f / (2f * PI_F * cutoffHz)
+        val dt = 1.0f / sampleRate
+        val alpha = dt / (rc + dt)
+        z1 = alpha * (z1 + sample - z1)
+        return sample - z1
+    }
+
+    fun lowPass(sample: Float, cutoffHz: Float, sampleRate: Float): Float {
+        val rc = 1.0f / (2f * PI_F * cutoffHz)
+        val dt = 1.0f / sampleRate
+        val alpha = dt / (rc + dt)
+        z1 += alpha * (sample - z1)
+        return z1
+    }
+
+    fun reset() { z1 = 0f }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwGoertzel.kt

@@ -0,0 +1,54 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+import kotlin.math.cos
+import kotlin.math.sqrt
+
+/**
+ * Running Goertzel filter for CW tone detection.
+ * Tracks a specific frequency over time with a sliding window.
+ * Ported from ggmorse/src/goertzel.h
+ */
+internal class CwGoertzel {
+    private var s1 = 0.0
+    private var s2 = 0.0
+    private var coeff = 0.0
+
+    fun init(sampleRate: Float, targetFreq: Float) {
+        val omega = 2.0 * kotlin.math.PI * targetFreq / sampleRate
+        coeff = 2.0 * cos(omega)
+        s1 = 0.0
+        s2 = 0.0
+    }
+
+    fun process(sample: Float) {
+        val s0 = sample.toDouble() + coeff * s1 - s2
+        s2 = s1
+        s1 = s0
+    }
+
+    fun getPower(): Float {
+        return sqrt(s2 * s2 + s1 * s1 - coeff * s1 * s2).toFloat()
+    }
+
+    fun reset() {
+        s1 = 0.0
+        s2 = 0.0
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwResampler.kt

@@ -0,0 +1,53 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+/**
+ * Simple linear resampler.
+ * Downsamples from input sample rate to output sample rate.
+ * Ported from ggmorse/src/resampler.h
+ */
+internal class CwResampler(private val inputRate: Float, private val outputRate: Float) {
+    private val ratio = inputRate / outputRate
+    private var lastSample = 0f
+
+    fun process(input: FloatArray): FloatArray {
+        if (ratio <= 0f || input.isEmpty()) return input
+        val outputLen = (input.size / ratio).toInt() + 1
+        val output = FloatArray(outputLen)
+        var idx = 0f
+        for (i in output.indices) {
+            val intIdx = idx.toInt()
+            val frac = idx - intIdx
+            if (intIdx + 1 < input.size) {
+                output[i] = input[intIdx] * (1 - frac) + input[intIdx + 1] * frac
+            } else if (intIdx < input.size) {
+                output[i] = input[intIdx] * (1 - frac) + lastSample * frac
+            } else {
+                output[i] = lastSample
+            }
+            idx += ratio
+        }
+        lastSample = input.lastOrNull() ?: lastSample
+        return output
+    }
+
+    fun reset() {
+        lastSample = 0f
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwSTFFT.kt

@@ -0,0 +1,61 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+import kotlin.math.cos
+import kotlin.math.sin
+import kotlin.math.sqrt
+
+/**
+ * Lightweight pitch detector using DFT at specific frequency bins.
+ * Only scans [200, 1200] Hz in configurable steps — much faster than full FFT.
+ * Ported from ggmorse/src/stfft.h (simplified for CW use case).
+ */
+internal class CwPitchDetector(
+    private val sampleRate: Float,
+    private val minFreq: Float = 200f,
+    private val maxFreq: Float = 1200f,
+    private val stepHz: Float = 10f
+) {
+    /**
+     * Find the dominant pitch frequency in the buffer.
+     * Returns null if no significant pitch found.
+     */
+    fun findPitch(buffer: FloatArray): Float? {
+        if (buffer.isEmpty()) return null
+        var bestFreq = 0f
+        var bestPower = 0f
+        var freq = minFreq
+        while (freq <= maxFreq) {
+            var real = 0.0
+            var imag = 0.0
+            val omega = 2.0 * kotlin.math.PI * freq / sampleRate
+            for (i in buffer.indices) {
+                real += buffer[i] * cos(omega * i)
+                imag += buffer[i] * -sin(omega * i)
+            }
+            val power = (real * real + imag * imag).toFloat()
+            if (power > bestPower) {
+                bestPower = power
+                bestFreq = freq
+            }
+            freq += stepHz
+        }
+        return if (bestPower > 0.001f) bestFreq else null
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/cw/CwSpectrogram.kt

@@ -0,0 +1,170 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.cw
+
+/**
+ * Sliding-window spectrogram for CW decoding.
+ * Maintains a time-frequency matrix updated with each audio frame.
+ *
+ * FFT size: 256, hop size: 64, sample rate: 4000 (or native)
+ * Frequency bins: 6..38 (187-1187 Hz, covers typical CW range)
+ * History: 40 columns (320 ms window)
+ * Time resolution: 64/4000 = 16 ms, Frequency resolution: 4000/256 = 15.625 Hz
+ */
+internal class CwSpectrogram(
+    private val fftSize: Int = 256,
+    private val hopSize: Int = 64,
+    private val sampleRate: Int = 4000,
+    private val minBin: Int = 6,
+    private val maxBin: Int = 38,
+    val historyCols: Int = 40
+) {
+    private val fft = CwFFT(fftSize)
+    val numBins: Int get() = maxBin - minBin + 1
+
+    // Hanning window
+    private val hanning = FloatArray(fftSize) {
+        (0.5 - 0.5 * kotlin.math.cos(2.0 * kotlin.math.PI * it / (fftSize - 1))).toFloat()
+    }
+
+    // Spectrogram data: [timeCol][freqBin]
+    private val spectrogram = Array(historyCols) { FloatArray(numBins) }
+    private var currentCol = 0
+    private var samplesBuffered = 0
+    private val buffer = FloatArray(fftSize)
+
+    // Per-bin running energy for normalization
+    private val binEnergy = FloatArray(numBins) { 1f }
+    private val alpha = 0.95f
+
+    // Counter for new columns generated since last check
+    private var newColumnCount = 0
+
+    /** Add audio samples, compute FFTs for each complete hop. */
+    fun addSamples(samples: FloatArray) {
+        var offset = 0
+        while (offset < samples.size) {
+            val needed = fftSize - samplesBuffered
+            val copyLen = minOf(needed, samples.size - offset)
+            System.arraycopy(samples, offset, buffer, samplesBuffered, copyLen)
+            samplesBuffered += copyLen
+            offset += copyLen
+
+            if (samplesBuffered >= fftSize) {
+                processFrame()
+                newColumnCount++
+                // Shift buffer: keep last (fftSize - hopSize) samples
+                System.arraycopy(buffer, hopSize, buffer, 0, fftSize - hopSize)
+                samplesBuffered = fftSize - hopSize
+            }
+        }
+    }
+
+    /** Get number of new columns generated since the last call to this method. */
+    fun getNewColumns(): Int {
+        val count = newColumnCount
+        newColumnCount = 0
+        return count
+    }
+
+    private fun processFrame() {
+        // Apply Hanning window
+        val windowed = FloatArray(fftSize) { buffer[it] * hanning[it] }
+
+        // Compute FFT magnitude spectrum
+        val mag = fft.magnitudeSpectrum(windowed)
+
+        // Update spectrogram column
+        val col = spectrogram[currentCol]
+        for (b in 0 until numBins) {
+            val binIdx = minBin + b
+            val rawMag = mag[binIdx]
+            // Running energy normalization
+            binEnergy[b] = alpha * binEnergy[b] + (1 - alpha) * rawMag
+            col[b] = if (binEnergy[b] > 1e-6f) rawMag / binEnergy[b] else 0f
+        }
+
+        currentCol = (currentCol + 1) % historyCols
+    }
+
+    /** Get the current spectrogram as a 2D array in chronological order. */
+    fun getSpectrogram(): Array<FloatArray> {
+        val result = Array(historyCols) { i ->
+            val srcIdx = (currentCol + i) % historyCols
+            spectrogram[srcIdx].copyOf()
+        }
+        return result
+    }
+
+    /** Get the most recent column (current energy across all frequencies). */
+    fun getCurrentColumn(): FloatArray {
+        val prevCol = (currentCol - 1 + historyCols) % historyCols
+        return spectrogram[prevCol].copyOf()
+    }
+
+    /** Get a column by index from the history (0 = oldest, historyCols-1 = newest). */
+    fun getColumn(index: Int): FloatArray {
+        val clamped = index.coerceIn(0, historyCols - 1)
+        val srcIdx = (currentCol - historyCols + clamped + historyCols) % historyCols
+        return spectrogram[srcIdx].copyOf()
+    }
+
+    /** Find the frequency bin with peak energy. Returns -1 if no significant signal. */
+    fun findPeakBin(): Int {
+        val col = getCurrentColumn()
+        var maxBin = -1
+        var maxVal = 0f
+        for (i in col.indices) {
+            if (col[i] > maxVal) {
+                maxVal = col[i]
+                maxBin = i
+            }
+        }
+        return if (maxVal > 0.3f) maxBin else -1
+    }
+
+    /** Get energy at a specific bin over the last N columns in chronological order. */
+    fun getBinEnergy(bin: Int, numCols: Int): FloatArray {
+        val clamped = minOf(numCols, historyCols)
+        val result = FloatArray(clamped)
+        for (i in 0 until clamped) {
+            val colIdx = (currentCol - clamped + i + historyCols) % historyCols
+            result[i] = spectrogram[colIdx][bin]
+        }
+        return result
+    }
+
+    /** Get the bin index for a frequency in Hz. */
+    fun freqToBin(freqHz: Float): Int {
+        val bin = (freqHz * fftSize / sampleRate).toInt()
+        return (bin - minBin).coerceIn(0, numBins - 1)
+    }
+
+    /** Get the center frequency for a bin. */
+    fun binToFreq(bin: Int): Float {
+        return (minBin + bin).toFloat() * sampleRate / fftSize
+    }
+
+    fun reset() {
+        for (col in spectrogram) col.fill(0f)
+        currentCol = 0
+        samplesBuffered = 0
+        buffer.fill(0f)
+        binEnergy.fill(1f)
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/AmSatReportSubmission.kt

@@ -0,0 +1,17 @@
+package com.rtbishop.look4sat.core.domain.model
+
+/** One public AMSAT satellite status report submission. */
+data class AmSatReportSubmission(
+    val name: String,
+    val report: String,
+    val callsign: String,
+    val gridSquare: String,
+    val reportedAtUtcMillis: Long
+)
+
+/** Result of submitting an AMSAT satellite status report. */
+data class AmSatReportSubmitResult(
+    val success: Boolean,
+    val message: String = "",
+    val reportId: String? = null
+)

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/AwardCalculator.kt

@@ -0,0 +1,194 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.model
+
+/**
+ * Award progress computed from the confirmed-QSO store.
+ *
+ * @param type      which award
+ * @param workedKeys matching keys for the boundary assets: each is compared
+ *                   against the region "code" field of the award's GeoJSON
+ *                   (e.g. WAPC -> "GD", WAJA -> "34", WAZ -> "24",
+ *                   WAS -> "CA", DXCC -> "318", VUCC -> "OL62").
+ * @param count     distinct worked units (grids / entities / provinces / ...)
+ * @param target    units required for the award
+ */
+data class AwardProgress(
+    val type: AwardType,
+    val workedKeys: Set<String>,
+    val count: Int,
+    val target: Int
+)
+
+enum class AwardType { DXCC, VUCC, WAPC, WAJA, WAZ, WAS }
+
+object AwardTargets {
+    const val DXCC = 100
+    const val VUCC = 100
+    const val WAPC = 34
+    const val WAJA = 47
+    const val WAZ = 40
+    const val WAS = 50
+}
+
+/**
+ * Derives six-award progress from the confirmed QSO store.
+ *
+ * Award rules (ADIF / award-program semantics):
+ *  - VUCC: distinct 4-char gridsquares.
+ *  - DXCC: distinct ARRL DXCC entities (from the QSO's dxcc field; falls back
+ *    to a callsign-prefix guess when LoTW omitted it).
+ *  - WAPC: distinct Chinese provinces (31 mainland STATE codes) plus the
+ *    Hong Kong / Macao / Taiwan entities (counted as their own provinces).
+ *  - WAJA: distinct Japanese prefectures (STATE code "01".."47").
+ *  - WAZ: distinct CQ zones.
+ *  - WAS: distinct US states (STATE abbreviations).
+ *
+ * The ADIF STATE field's meaning depends on the DXCC entity
+ * ("STATE depends on DXCC"), so every QSO is first classified by entity.
+ */
+object AwardCalculator {
+
+    fun calculate(qsosByGrid: Map<String, List<GridQso>>): List<AwardProgress> {
+        val all = qsosByGrid.values.flatten()
+        return listOf(
+            AwardProgress(
+                AwardType.VUCC,
+                workedKeys = qsosByGrid.keys,
+                count = qsosByGrid.size,
+                target = AwardTargets.VUCC
+            ),
+            calculateDxcc(all),
+            calculateWapc(all),
+            calculateWaja(all),
+            calculateWaz(all),
+            calculateWas(all)
+        )
+    }
+
+    private fun calculateDxcc(all: List<GridQso>): AwardProgress {
+        val keys = mutableSetOf<String>()
+        for (q in all) {
+            val code = q.dxcc ?: prefixEntityCode(q.call)
+            if (code != null) keys.add(code.toString())
+        }
+        return AwardProgress(AwardType.DXCC, keys, keys.size, AwardTargets.DXCC)
+    }
+
+    private fun calculateWapc(all: List<GridQso>): AwardProgress {
+        val keys = mutableSetOf<String>()
+        for (q in all) {
+            when (entityOf(q)) {
+                Entity.CHINA -> q.state?.trim()?.uppercase()?.takeIf { it in CN_STATES }?.let { keys.add(it) }
+                Entity.HONG_KONG -> keys.add(HK_CODE)
+                Entity.MACAO -> keys.add(MO_CODE)
+                Entity.TAIWAN -> keys.add(TW_CODE)
+                else -> {}
+            }
+        }
+        return AwardProgress(AwardType.WAPC, keys, keys.size, AwardTargets.WAPC)
+    }
+
+    private fun calculateWaja(all: List<GridQso>): AwardProgress {
+        val keys = mutableSetOf<String>()
+        for (q in all) {
+            if (entityOf(q) != Entity.JAPAN) continue
+            q.state?.trim()?.takeIf { it.length == 2 && it.all(Char::isDigit) }?.let { keys.add(it) }
+        }
+        return AwardProgress(AwardType.WAJA, keys, keys.size, AwardTargets.WAJA)
+    }
+
+    private fun calculateWaz(all: List<GridQso>): AwardProgress {
+        val keys = mutableSetOf<String>()
+        for (q in all) {
+            q.cqz?.takeIf { it in 1..40 }?.let { keys.add(it.toString()) }
+        }
+        return AwardProgress(AwardType.WAZ, keys, keys.size, AwardTargets.WAZ)
+    }
+
+    private fun calculateWas(all: List<GridQso>): AwardProgress {
+        val keys = mutableSetOf<String>()
+        for (q in all) {
+            if (entityOf(q) != Entity.USA) continue
+            q.state?.trim()?.uppercase()?.takeIf { it in US_STATES }?.let { keys.add(it) }
+        }
+        return AwardProgress(AwardType.WAS, keys, keys.size, AwardTargets.WAS)
+    }
+
+    private enum class Entity { CHINA, HONG_KONG, MACAO, TAIWAN, JAPAN, USA, OTHER }
+
+    private fun entityOf(q: GridQso): Entity = when (q.dxcc) {
+        318 -> Entity.CHINA
+        321 -> Entity.HONG_KONG
+        152 -> Entity.MACAO
+        386 -> Entity.TAIWAN
+        339 -> Entity.JAPAN
+        291 -> Entity.USA
+        else -> prefixEntity(q.call)
+    }
+
+    /** Coarse entity from callsign prefix, used when LoTW omitted the DXCC field. */
+    private fun prefixEntity(call: String): Entity {
+        val c = call.uppercase().substringBefore('/')
+        return when {
+            CN_PREFIXES.any { c.startsWith(it) } -> Entity.CHINA
+            c.startsWith("VR") -> Entity.HONG_KONG
+            c.startsWith("XX9") -> Entity.MACAO
+            TW_PREFIXES.any { c.startsWith(it) } -> Entity.TAIWAN
+            JP_PREFIXES.any { c.startsWith(it) } -> Entity.JAPAN
+            US_PREFIXES.any { c.startsWith(it) } -> Entity.USA
+            else -> Entity.OTHER
+        }
+    }
+
+    /** ARRL DXCC entity code guessed from callsign prefix (very coarse). */
+    private fun prefixEntityCode(call: String): Int? {
+        return when (prefixEntity(call)) {
+            Entity.CHINA -> 318
+            Entity.HONG_KONG -> 321
+            Entity.MACAO -> 152
+            Entity.TAIWAN -> 386
+            Entity.JAPAN -> 339
+            Entity.USA -> 291
+            else -> null
+        }
+    }
+
+    private val CN_PREFIXES = listOf("BA", "BD", "BG", "BH", "BI", "BY", "BJ", "BK", "BL", "BQ", "BR", "BS")
+    private val TW_PREFIXES = listOf("BM", "BV", "BU", "BW", "BX", "BN", "BO", "BT", "BZ")
+    private val JP_PREFIXES =
+        listOf("7J", "7K", "7L", "7M", "7N") + ('A'..'Z').map { "J$it" }
+    private val US_PREFIXES =
+        listOf("AA", "AB", "AC", "AD", "AE", "AF", "AG", "AH", "AI", "AJ", "AK", "AL", "K", "N", "W")
+
+    private val CN_STATES = setOf(
+        "AH", "BJ", "CQ", "FJ", "GD", "GS", "GX", "GZ", "HA", "HB", "HE", "HI", "HL", "HN", "JL",
+        "JS", "JX", "LN", "NM", "NX", "QH", "SC", "SD", "SH", "SN", "SX", "TJ", "XJ", "XZ", "YN", "ZJ"
+    )
+
+    private val US_STATES = setOf(
+        "AL", "AK", "AZ", "AR", "CA", "CO", "CT", "DE", "FL", "GA", "HI", "ID", "IL", "IN", "IA",
+        "KS", "KY", "LA", "ME", "MD", "MA", "MI", "MN", "MS", "MO", "MT", "NE", "NV", "NH", "NJ",
+        "NM", "NY", "NC", "ND", "OH", "OK", "OR", "PA", "RI", "SC", "SD", "TN", "TX", "UT", "VT",
+        "VA", "WA", "WV", "WI", "WY"
+    )
+
+    private const val HK_CODE = "HK"
+    private const val MO_CODE = "MO"
+    private const val TW_CODE = "TW"
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/Constants.kt

@@ -0,0 +1,23 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.model
+
+object Constants {
+    const val FREQ_OFFSET_MIN_HZ = -50_000L
+    const val FREQ_OFFSET_MAX_HZ = 50_000L
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/GridQso.kt

@@ -0,0 +1,76 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.model
+
+/**
+ * One confirmed satellite QSO as reported by LoTW, kept per worked gridsquare
+ * so the map can show, for any worked grid, which callsigns were worked there
+ * and when.
+ *
+ * @param call      opposite station callsign (as logged by the opposite op)
+ * @param epochMs   QSO date+time in UTC milliseconds
+ * @param satName   satellite name (e.g. "FO-29")
+ * @param mode      ADIF mode (FM / CW / SSB ...)
+ * @param bandUp    uplink band as reported by LoTW (BAND_RX: "70CM", "2M", "10M"...)
+ * @param bandDown  downlink band (BAND: "2M", "70CM"...) — may be empty when
+ *                  LoTW did not include it
+ * @param dxcc      ARRL DXCC entity code of the opposite station (from ADIF
+ *                  <DXCC>), or null when LoTW omitted it
+ * @param country   DXCC entity name (ADIF <COUNTRY>), or null
+ * @param cqz       CQ zone of the opposite station (ADIF <CQZ>), or null
+ * @param state     Primary administrative subdivision of the opposite station
+ *                  (ADIF <STATE>). Interpretation depends on the DXCC entity:
+ *                  China -> province code ("GD"), Japan -> prefecture number
+ *                  ("34"), USA -> state abbreviation ("CA"). Null when absent.
+ */
+data class GridQso(
+    val call: String,
+    val epochMs: Long,
+    val satName: String,
+    val mode: String,
+    val bandUp: String,
+    val bandDown: String,
+    val dxcc: Int? = null,
+    val country: String? = null,
+    val cqz: Int? = null,
+    val state: String? = null
+) {
+    /** Short uplink/downlink band label ("U/V", "V/A"), or "" when unknown. */
+    val bandLabel: String
+        get() {
+            val up = bandAbbrev(bandUp)
+            val down = bandAbbrev(bandDown)
+            return when {
+                up.isNotEmpty() && down.isNotEmpty() -> "$up/$down"
+                up.isNotEmpty() -> up
+                else -> ""
+            }
+        }
+
+    private fun bandAbbrev(band: String): String = when (band.trim().uppercase()) {
+        "70CM" -> "U"
+        "2M" -> "V"
+        "10M" -> "A"
+        "6M" -> "V"
+        "1.2G" -> "L"
+        "2.4G" -> "S"
+        "23CM" -> "L"
+        "13CM" -> "S"
+        else -> band.trim().uppercase()
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/LatestRelease.kt

@@ -0,0 +1,9 @@
+package com.rtbishop.look4sat.core.domain.model
+
+/** Latest release info fetched from the fork's GitHub releases API. */
+data class LatestRelease(
+    val versionTag: String, // e.g. "v4.4.6-ba7opf.6"
+    val title: String,      // release name, may be empty
+    val body: String,       // release notes / update description
+    val apkUrl: String?     // first .apk asset download URL, null if absent
+)

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/SatRadio.kt

@@ -17,16 +17,20 @@
  */
 package com.rtbishop.look4sat.core.domain.model
 
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
 data class SatRadio(
-    val uuid: String,
-    val info: String,
-    val isAlive: Boolean,
-    var downlinkLow: Long?,
-    var downlinkHigh: Long?,
-    val downlinkMode: String?,
-    var uplinkLow: Long?,
-    var uplinkHigh: Long?,
-    val uplinkMode: String?,
-    val isInverted: Boolean,
-    val catnum: Int?
+    @SerialName("uuid") val uuid: String,
+    @SerialName("description") val info: String,
+    @SerialName("alive") val isAlive: Boolean,
+    @SerialName("downlink_low") val downlinkLow: Long?,
+    @SerialName("downlink_high") val downlinkHigh: Long?,
+    @SerialName("mode") val downlinkMode: String?,
+    @SerialName("uplink_low") val uplinkLow: Long?,
+    @SerialName("uplink_high") val uplinkHigh: Long?,
+    @SerialName("uplink_mode") val uplinkMode: String?,
+    @SerialName("invert") val isInverted: Boolean,
+    @SerialName("norad_cat_id") val catnum: Int?
 )

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/SatStatus.kt

@@ -0,0 +1,37 @@
+package com.rtbishop.look4sat.core.domain.model
+
+/** One satellite status report (AMSAT site tooltip data) */
+data class SatReport(
+    val id: String,          // 报告 ID(a885153)
+    val statusText: String,  // Heard / Telemetry Only / Not Heard ...
+    val call: String,        // 呼号
+    val grid: String,        // 网格坐标(可为空)
+    val dateUtc: String,     // 2026-08-04
+    val timeUtc: String      // 2:46-:59 UTC
+)
+
+/** State of one 2-hour slot */
+data class SatSlot(
+    val statusColor: Long,   // ARGB 状态色(-1 = 无报告)
+    val count: Int,          // 报告数量(0 = 无)
+    val reportIds: List<String> = emptyList() // 该槽报告 ID 列表
+)
+
+/** One satellite day (12 two-hour slots) */
+data class SatDay(
+    val dateLabel: String,   // "Aug 4"
+    val slots: List<SatSlot> // 12 槽(00-02 ... 22-24)
+)
+
+/** One satellite, 3 days of state */
+data class SatStatus(
+    val name: String,        // "AO-123_[FM]"
+    val days: List<SatDay>   // 3 days (newest first)
+)
+
+/** Overall page parse result */
+data class SatStatusPage(
+    val fetchedAtUtcMs: Long,
+    val statuses: List<SatStatus>,
+    val reports: Map<String, SatReport> // id → 报告
+)

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/Settings.kt

@@ -24,8 +24,12 @@ data class DatabaseState(
 )
 
 data class PassesSettings(
+    val showDeepSpace: Boolean = true,
     val hoursAhead: Int,
     val minElevation: Double,
+    val aosStartMinute: Int = 0,
+    val aosEndMinute: Int = 23 * 60 + 59,
+    val invertAosTimeWindow: Boolean = false,
     val selectedModes: List<String>
 )
 
@@ -38,6 +42,7 @@ data class RCSettings(
     val frequencyAddress: String,
     val frequencyPort: String,
     val frequencyFormat: String,
+    val frequencyOffsetHz: Long = 0L,
     val bluetoothRotatorState: Boolean,
     val bluetoothRotatorFormat: String,
     val bluetoothRotatorName: String,
@@ -53,13 +58,60 @@ data class OtherSettings(
     val stateOfSweep: Boolean,
     val stateOfUtc: Boolean,
     val stateOfLightTheme: Boolean,
+    val stateOfNightMode: Boolean = false,
+    val stateOfMapGrid: Boolean = false,
     val shouldSeeWarning: Boolean,
-    val shouldSeeWhatsNew: Boolean
+    val shouldSeeWhatsNew: Boolean,
+    val sstvMode: String = "Auto",
+    val lowElevation: Double = 15.0,
+    val highElevation: Double = 45.0
 )
 
 data class DataSourcesSettings(
-    val useCustomTLE: Boolean,
-    val useCustomTransceivers: Boolean,
-    val tleUrl: String,
-    val transceiversUrl: String
-)
+    val satelliteUrls: List<String>,
+    val transceiversUrls: List<String>,
+    val satelliteEnabled: List<Boolean> = emptyList(),
+    val transceiversEnabled: List<Boolean> = emptyList()
+) {
+    fun isSatelliteEnabled(index: Int): Boolean = satelliteEnabled.getOrElse(index) { true }
+    fun isTransceiverEnabled(index: Int): Boolean = transceiversEnabled.getOrElse(index) { true }
+}
+
+data class WavelogSettings(
+    val url: String = "",
+    val token: String = ""
+) {
+    val isConfigured: Boolean get() = url.isNotBlank() && token.isNotBlank()
+}
+
+data class LoTWSettings(
+    val callsign: String = "",
+    val password: String = ""
+) {
+    val isConfigured: Boolean get() = callsign.isNotBlank() && password.isNotBlank()
+}
+
+data class RadioControlSettings(
+    val enabled: Boolean,
+    val radioModel: String,
+    val txRadioAddress: String,
+    val rxRadioAddress: String,
+    val txRadioName: String,
+    val rxRadioName: String,
+    val baudRate: Int,
+    /** IC-705 only: use single-radio split-VFO mode instead of two radios. */
+    val splitMode: Boolean = false
+) {
+    companion object {
+        const val MODEL_YAESU_FT817   = "Yaesu FT-817/818"
+        const val MODEL_YAESU_FT857   = "Yaesu FT-857/897"
+        const val MODEL_ICOM_IC705    = "Icom IC-705"
+
+        val SUPPORTED_RADIOS = listOf(MODEL_YAESU_FT817, MODEL_YAESU_FT857, MODEL_ICOM_IC705)
+
+        /** Baud rates available for Yaesu radios. */
+        val BAUD_RATES_YAESU = listOf(4800, 9600, 38400)
+        /** Baud rates available for Icom IC-705 (higher speeds supported via CI-V USB/BT). */
+        val BAUD_RATES_ICOM  = listOf(4800, 9600, 19200, 38400, 57600, 115200)
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/CelestialComputer.kt

@@ -0,0 +1,671 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.predict
+
+import com.rtbishop.look4sat.core.domain.utility.toDegrees
+import com.rtbishop.look4sat.core.domain.utility.toRadians
+import kotlin.math.PI
+import kotlin.math.abs
+import kotlin.math.acos
+import kotlin.math.asin
+import kotlin.math.atan
+import kotlin.math.atan2
+import kotlin.math.cos
+import kotlin.math.floor
+import kotlin.math.log10
+import kotlin.math.pow
+import kotlin.math.sin
+import kotlin.math.sqrt
+import kotlin.math.tan
+
+/**
+ * Standalone celestial computations extracted from PREDICT v2.2.5.
+ * Provides Sun position, Moon position, satellite visibility classification,
+ * orbital metadata, RA/Dec conversion, and rise/set finding for Sun and Moon.
+ *
+ * All angles are in degrees unless noted. Time is Unix epoch milliseconds.
+ *
+ * Shared math utilities (thetaGJD, modulus, mod2PI, deltaET, millisToDaynum,
+ * solarPositionECI, eciToGeodetic) live in OrbitalMath.kt in the same package.
+ */
+object CelestialComputer {
+
+    // ── Result types ──
+
+    /** Sun position as seen from a ground observer. */
+    data class SunPosition(
+        val azimuth: Double,         // degrees, 0=N, 90=E
+        val elevation: Double,       // degrees, >0 above horizon
+        val distance: Double,        // normalized: 1.0 + ((range - AU) / AU)
+        val rangeRate: Double,       // km/s
+        val latitude: Double,        // sub-solar point latitude, degrees
+        val longitude: Double,       // sub-solar point longitude, degrees
+        val rightAscension: Double,  // degrees
+        val declination: Double      // degrees
+    )
+
+    /** Moon position as seen from a ground observer. */
+    data class MoonPosition(
+        val azimuth: Double,         // degrees, 0=N, 90=E
+        val elevation: Double,       // degrees
+        val rightAscension: Double,  // degrees
+        val declination: Double,     // degrees
+        val gha: Double,             // Greenwich Hour Angle, degrees
+        val angularDiameter: Double, // apparent diameter relative to Earth's diameter
+        val radialVelocity: Double   // m/s, Doppler radial velocity for EME
+    )
+
+    /**
+     * 3-state satellite visibility classification.
+     * - [VISIBLE]: satellite is sunlit, observer is in darkness (sun below -12°) — optically visible
+     * - [DAYLIGHT]: satellite is sunlit, observer is in daylight
+     * - [ECLIPSED]: satellite is in Earth's shadow
+     */
+    enum class SatVisibility { VISIBLE, DAYLIGHT, ECLIPSED }
+
+    /** Orbital metadata not typically included in pass data. */
+    data class OrbitalMetadata(
+        val footprintDiameter: Double, // km, ground coverage circle diameter
+        val orbitNumber: Long,         // current orbit/revolution number
+        val betaAngle: Double,         // degrees, angle between orbital plane and Sun
+        val orbitalPhase: Double       // 0-256 phase within current orbit
+    )
+
+    // ── Sun position ──
+
+    /**
+     * Compute the Sun's full position as seen from [observer] at [timeMillis].
+     * Includes az/el, RA/Dec, sub-solar lat/lon, range, and range rate.
+     * Based on FindSun() from PREDICT v2.2.5.
+     */
+    fun getSunPosition(observer: GeoPos, timeMillis: Long): SunPosition {
+        val daynum = millisToDaynum(timeMillis)
+        val julUtc = daynum + 2444238.5
+        val sunVec = solarPositionECI(julUtc)
+        val zeroVel = doubleArrayOf(0.0, 0.0, 0.0)
+        val obsGeo = observerGeodetic(observer)
+
+        // Az, El, Range, RangeRate
+        val obsSet = computeObsAngles(julUtc, sunVec, zeroVel, obsGeo)
+
+        // Lat/Lon of sub-solar point
+        val latLon = eciToGeodetic(julUtc, sunVec)
+
+        // RA/Dec
+        val raDec = calculateRADec(julUtc, sunVec, zeroVel, obsGeo)
+
+        return SunPosition(
+            azimuth = obsSet[0].toDegrees(),
+            elevation = obsSet[1].toDegrees(),
+            distance = 1.0 + ((obsSet[2] - ASTRONOMICAL_UNIT) / ASTRONOMICAL_UNIT),
+            rangeRate = 1000.0 * obsSet[3],
+            latitude = latLon[0].toDegrees(),
+            longitude = latLon[1].toDegrees().let { if (it > 180.0) it - 360.0 else it },
+            rightAscension = raDec[0].toDegrees(),
+            declination = raDec[1].toDegrees()
+        )
+    }
+
+    // ── Moon position ──
+
+    /**
+     * Compute the Moon's position as seen from [observer] at [timeMillis].
+     * Full Meeus lunar ephemeris from PREDICT v2.2.5 with expanded terms
+     * and radial velocity approximation for EME Doppler.
+     */
+    fun getMoonPosition(observer: GeoPos, timeMillis: Long): MoonPosition {
+        val daynum = millisToDaynum(timeMillis)
+        val jd = daynum + 2444238.5
+        var t = (jd - 2415020.0) / 36525.0
+        val t2 = t * t
+        val t3 = t2 * t
+
+        var l1 = 270.434164 + 481267.8831 * t - 0.001133 * t2 + 0.0000019 * t3
+        var mSun = 358.475833 + 35999.0498 * t - 0.00015 * t2 - 0.0000033 * t3
+        var m1 = 296.104608 + 477198.8491 * t + 0.009192 * t2 + 0.0000144 * t3
+        var d = 350.737486 + 445267.1142 * t - 0.001436 * t2 + 0.0000019 * t3
+        var ff = 11.250889 + 483202.0251 * t - 0.003211 * t2 - 0.0000003 * t3
+        val om = (259.183275 - 1934.142 * t + 0.002078 * t2 + 0.0000022 * t3) * DEG2RAD
+
+        val correction512 = sin((51.2 + 20.2 * t) * DEG2RAD)
+        val ss = 0.003964 * sin((346.56 + 132.87 * t - 0.0091731 * t2) * DEG2RAD)
+        l1 += 0.000233 * correction512 + ss + 0.001964 * sin(om)
+        mSun -= 0.001778 * correction512
+        m1 += 0.000817 * correction512 + ss + 0.002541 * sin(om)
+        d += 0.002011 * correction512 + ss + 0.001964 * sin(om)
+        ff += ss - 0.024691 * sin(om) - 0.004328 * sin(om + (275.05 - 2.3 * t) * DEG2RAD)
+
+        val ex = 1.0 - 0.002495 * t - 0.00000752 * t2
+        l1 = primeAngle(l1); mSun = primeAngle(mSun); m1 = primeAngle(m1)
+        d = primeAngle(d); ff = primeAngle(ff)
+
+        val mR = mSun * DEG2RAD
+        val m1R = m1 * DEG2RAD
+        val dR = d * DEG2RAD
+        val ffR = ff * DEG2RAD
+
+        // Ecliptic longitude — expanded v225 terms
+        var l = l1 + 6.28875 * sin(m1R) + 1.274018 * sin(2 * dR - m1R) + 0.658309 * sin(2 * dR)
+        l += 0.213616 * sin(2 * m1R) - ex * 0.185596 * sin(mR) - 0.114336 * sin(2 * ffR)
+        l += 0.058793 * sin(2 * dR - 2 * m1R) + ex * 0.057212 * sin(2 * dR - mR - m1R) + 0.05332 * sin(2 * dR + m1R)
+        l += ex * 0.045874 * sin(2 * dR - mR) + ex * 0.041024 * sin(m1R - mR) - 0.034718 * sin(dR)
+        l -= ex * 0.030465 * sin(mR + m1R) + 0.015326 * sin(2 * dR - 2 * ffR) - 0.012528 * sin(2 * ffR + m1R)
+        l -= 0.01098 * sin(2 * ffR - m1R) + 0.010674 * sin(4 * dR - m1R) + 0.010034 * sin(3 * m1R)
+        l += 0.008548 * sin(4 * dR - 2 * m1R) - ex * 0.00791 * sin(mR - m1R + 2 * dR)
+        l -= ex * 0.006783 * sin(2 * dR + mR)
+        l += 0.005162 * sin(m1R - dR) + ex * 0.005 * sin(mR + dR) + ex * 0.004049 * sin(m1R - mR + 2 * dR)
+        l += 0.003996 * sin(2 * m1R + 2 * dR) + 0.003862 * sin(4 * dR) + 0.003665 * sin(2 * dR - 3 * m1R)
+        l += ex * 0.002695 * sin(2 * m1R - mR) + 0.002602 * sin(m1R - 2 * ffR - 2 * dR)
+        l += ex * 0.002396 * sin(2 * dR - mR - 2 * m1R)
+        l -= 0.002349 * sin(m1R + dR) + ex * ex * 0.002249 * sin(2 * dR - 2 * mR)
+        l -= ex * 0.002125 * sin(2 * m1R + mR)
+        l -= ex * ex * 0.002079 * sin(2 * mR) + ex * ex * 0.002059 * sin(2 * dR - m1R - 2 * mR)
+        l -= 0.001773 * sin(m1R + 2 * dR - 2 * ffR)
+        l += ex * 0.00122 * sin(4 * dR - mR - m1R) - 0.00111 * sin(2 * m1R + 2 * ffR) + 0.000892 * sin(m1R - 3 * dR)
+        l -= ex * 0.000811 * sin(mR + m1R + 2 * dR) + ex * 0.000761 * sin(4 * dR - mR - 2 * m1R)
+        l += ex * ex * 0.000717 * sin(m1R - 2 * mR)
+        l += ex * ex * 0.000704 * sin(m1R - 2 * mR - 2 * dR) + ex * 0.000693 * sin(mR - 2 * m1R + 2 * dR)
+        l += ex * 0.000598 * sin(2 * dR - mR - 2 * ffR) + 0.00055 * sin(m1R + 4 * dR)
+        l += 0.000538 * sin(4 * m1R) + ex * 0.000521 * sin(4 * dR - mR) + 0.000486 * sin(2 * m1R - dR)
+        l -= 0.001595 * sin(2 * ffR + 2 * dR)
+
+        // Ecliptic latitude — expanded v225 terms
+        var b =
+            5.128189 * sin(ffR) + 0.280606 * sin(m1R + ffR) + 0.277693 * sin(m1R - ffR) + 0.173238 * sin(2 * dR - ffR)
+        b += 0.055413 * sin(2 * dR + ffR - m1R) + 0.046272 * sin(2 * dR - ffR - m1R) + 0.032573 * sin(2 * dR + ffR)
+        b += 0.017198 * sin(2 * m1R + ffR) + 9.266999e-03 * sin(2 * dR + m1R - ffR) + 0.008823 * sin(2 * m1R - ffR)
+        b += ex * 0.008247 * sin(2 * dR - mR - ffR) + 0.004323 * sin(2 * dR - ffR - 2 * m1R)
+        b += 0.0042 * sin(2 * dR + ffR + m1R)
+        b += ex * 0.003372 * sin(ffR - mR - 2 * dR) + ex * 0.002472 * sin(2 * dR + ffR - mR - m1R)
+        b += ex * 0.002222 * sin(2 * dR + ffR - mR)
+        b += 0.002072 * sin(2 * dR - ffR - mR - m1R) + ex * 0.001877 * sin(ffR - mR + m1R)
+        b += 0.001828 * sin(4 * dR - ffR - m1R)
+        b -= ex * 0.001803 * sin(ffR + mR) - 0.00175 * sin(3 * ffR)
+        b += ex * 0.00157 * sin(m1R - mR - ffR) - 0.001487 * sin(ffR + dR)
+        b -= ex * 0.001481 * sin(ffR + mR + m1R) + ex * 0.001417 * sin(ffR - mR - m1R)
+        b += ex * 0.00135 * sin(ffR - mR) + 0.00133 * sin(ffR - dR)
+        b += 0.001106 * sin(ffR + 3 * m1R) + 0.00102 * sin(4 * dR - ffR) + 0.000833 * sin(ffR + 4 * dR - m1R)
+        b += 0.000781 * sin(m1R - 3 * ffR) + 0.00067 * sin(ffR + 4 * dR - 2 * m1R)
+        b += 0.000606 * sin(2 * dR - 3 * ffR)
+        b += 0.000597 * sin(2 * dR + 2 * m1R - ffR) + ex * 0.000492 * sin(2 * dR + m1R - mR - ffR)
+        b += 0.00045 * sin(2 * m1R - ffR - 2 * dR)
+        b += 0.000439 * sin(3 * m1R - ffR) + 0.000423 * sin(ffR + 2 * dR + 2 * m1R)
+        b += 0.000422 * sin(2 * dR - ffR - 3 * m1R)
+        b -= ex * 0.000367 * sin(mR + ffR + 2 * dR - m1R) - ex * 0.000353 * sin(mR + ffR + 2 * dR)
+        b += 0.000331 * sin(ffR + 4 * dR)
+        b += ex * 0.000317 * sin(2 * dR + ffR - mR + m1R) + ex * ex * 0.000306 * sin(2 * dR - 2 * mR - ffR)
+        b -= 0.000283 * sin(m1R + 3 * ffR)
+
+        val w1 = 0.0004664 * cos(om)
+        val w2 = 0.0000754 * cos(om + (275.05 - 2.3 * t) * DEG2RAD)
+        val bt = b * (1.0 - w1 - w2)
+
+        // Parallax — expanded v225 terms
+        var p =
+            0.950724 + 0.051818 * cos(m1R) + 0.009531 * cos(2 * dR - m1R) + 0.007843 * cos(2 * dR) + 0.002824 * cos(2 * m1R)
+        p += 0.000857 * cos(2 * dR + m1R) + ex * 0.000533 * cos(2 * dR - mR) + ex * 0.000401 * cos(2 * dR - mR - m1R)
+        p += 0.000173 * cos(3 * m1R) + 0.000167 * cos(4 * dR - m1R) - ex * 0.000111 * cos(mR)
+        p += 0.000103 * cos(4 * dR - 2 * m1R) - 0.000084 * cos(2 * m1R - 2 * dR) - ex * 0.000083 * cos(2 * dR + mR)
+        p += 0.000079 * cos(2 * dR + 2 * m1R)
+        p += 0.000072 * cos(4 * dR) + ex * 0.000064 * cos(2 * dR - mR + m1R) - ex * 0.000063 * cos(2 * dR + mR - m1R)
+        p += ex * 0.000041 * cos(mR + dR) + ex * 0.000035 * cos(2 * m1R - mR) - 0.000033 * cos(3 * m1R - 2 * dR)
+        p -= 0.00003 * cos(m1R + dR) - 0.000029 * cos(2 * ffR - 2 * dR) - ex * 0.000029 * cos(2 * m1R + mR)
+        p += ex * ex * 0.000026 * cos(2 * dR - 2 * mR) - 0.000023 * cos(2 * ffR - 2 * dR + m1R)
+        p += ex * 0.000019 * cos(4 * dR - mR - m1R)
+
+        val bRad = bt * DEG2RAD
+        val lm = l * DEG2RAD
+        val moonDx = 3.0 / (PI * p)
+
+        // Ecliptic → equatorial
+        val z = (jd - 2415020.5) / 365.2422
+        val ob = (23.452294 - (0.46845 * z + 5.9e-07 * z * z) / 3600.0).toRadians()
+        val dec = asin(sin(bRad) * cos(ob) + cos(bRad) * sin(ob) * sin(lm))
+        var ra = acos(cos(bRad) * cos(lm) / cos(dec)); if (lm > PI) ra = TWO_PI - ra
+
+        val n = observer.latitude * DEG2RAD
+        t = (jd - 2451545.0) / 36525.0
+        var teg = 280.46061837 + 360.98564736629 * (jd - 2451545.0) + (0.000387933 * t - t * t / 38710000.0) * t
+        while (teg > 360.0) teg -= 360.0
+        // LST = GMST + east longitude (positive east convention)
+        val th = mod2PI((teg + observer.longitude) * DEG2RAD)
+        val h = th - ra
+        val azVal = atan2(sin(h), cos(h) * sin(n) - tan(dec) * cos(n)) + PI
+        val el = asin(sin(n) * sin(dec) + cos(n) * cos(dec) * cos(h))
+
+        // Moon radial velocity approximation (from "Amateur Radio Software", GM4ANB, RSGB 1985)
+        val mm = fixAngle(1.319238 + daynum * 0.228027135)
+        val radT2 = 0.10976
+        val radT1 = mm + radT2 * sin(mm)
+        var dv = 0.01255 * moonDx * moonDx * sin(radT1) * (1.0 + radT2 * cos(mm))
+        dv *= 4449.0
+        val earthR = 6378.0
+        val moonDist = 384401.0
+        val radT3 = earthR * moonDist * (cos(dec) * cos(n) * sin(h)) /
+            sqrt(moonDist * moonDist - moonDist * earthR * sin(el))
+        val moonDv = dv + radT3 * 0.0753125
+
+        val moonRa = ra / DEG2RAD
+        var moonGha = teg - moonRa
+        if (moonGha < 0.0) moonGha += 360.0
+
+        return MoonPosition(
+            azimuth = azVal / DEG2RAD,
+            elevation = el / DEG2RAD,
+            rightAscension = moonRa,
+            declination = dec / DEG2RAD,
+            gha = moonGha,
+            angularDiameter = moonDx,
+            radialVelocity = moonDv
+        )
+    }
+
+    // ── Satellite visibility ──
+
+    /**
+     * Classify satellite visibility given its eclipse state and the Sun's elevation
+     * at the observer's location.
+     *
+     * @param isEclipsed whether the satellite is in Earth's shadow
+     * @param sunElevationDeg Sun elevation at observer in degrees
+     * @param satElevationDeg satellite elevation at observer in degrees (must be >= 0)
+     */
+    fun classifyVisibility(
+        isEclipsed: Boolean,
+        sunElevationDeg: Double,
+        satElevationDeg: Double
+    ): SatVisibility {
+        if (isEclipsed) return SatVisibility.ECLIPSED
+        return if (sunElevationDeg <= -12.0 && satElevationDeg >= 0.0) SatVisibility.VISIBLE
+        else SatVisibility.DAYLIGHT
+    }
+
+    // ── Orbital metadata ──
+
+    /**
+     * Compute orbital metadata for a satellite at its current position.
+     *
+     * @param altitudeKm satellite altitude in km
+     * @param meanMotion revolutions per day from TLE
+     * @param bstar drag term from TLE
+     * @param meanAnomaly mean anomaly at epoch (radians)
+     * @param revNumAtEpoch revolution number at TLE epoch
+     * @param ageDays days since TLE epoch (julUTC - julEpoch)
+     * @param phase orbital phase in radians (from SGP4/SDP4 output)
+     * @param satPosECI satellite ECI position [x, y, z]
+     * @param satVelECI satellite ECI velocity [vx, vy, vz]
+     * @param sunPosECI sun ECI position [x, y, z]
+     */
+    fun computeOrbitalMetadata(
+        altitudeKm: Double,
+        meanMotion: Double,
+        bstar: Double,
+        meanAnomaly: Double,
+        revNumAtEpoch: Int,
+        ageDays: Double,
+        phase: Double,
+        satPosECI: DoubleArray,
+        satVelECI: DoubleArray,
+        sunPosECI: DoubleArray
+    ): OrbitalMetadata {
+        // Footprint diameter (km)
+        val footprint = 12756.33 * acos(EARTH_RADIUS / (EARTH_RADIUS + altitudeKm))
+
+        // Orbit number
+        val xmnpda = 1.44E3
+        val orbitNum = floor(
+            (meanMotion * xmnpda / TWO_PI + ageDays * bstar) * ageDays + meanAnomaly / TWO_PI
+        ).toLong() + revNumAtEpoch
+
+        // Beta angle: angle between orbital plane and Sun direction
+        // Orbital plane normal = cross(pos, vel)
+        val nx = satPosECI[1] * satVelECI[2] - satPosECI[2] * satVelECI[1]
+        val ny = satPosECI[2] * satVelECI[0] - satPosECI[0] * satVelECI[2]
+        val nz = satPosECI[0] * satVelECI[1] - satPosECI[1] * satVelECI[0]
+        val nMag = sqrt(nx * nx + ny * ny + nz * nz)
+        val sMag = sqrt(sunPosECI[0] * sunPosECI[0] + sunPosECI[1] * sunPosECI[1] + sunPosECI[2] * sunPosECI[2])
+        val dotNS = nx * sunPosECI[0] + ny * sunPosECI[1] + nz * sunPosECI[2]
+        val betaAngle = if (nMag > 0 && sMag > 0) {
+            (PI / 2.0 - acos(dotNS / (nMag * sMag))).toDegrees()
+        } else 0.0
+
+        // Phase (0-256 scale, matching PREDICT convention)
+        val orbitalPhase = 256.0 * (phase / TWO_PI)
+
+        return OrbitalMetadata(footprint, orbitNum, betaAngle, orbitalPhase)
+    }
+
+    // ── Satellite status checks ──
+
+    /** Check if a satellite is geostationary (mean motion ≈ 1.0027 rev/day). */
+    fun isGeostationary(meanMotion: Double): Boolean = abs(meanMotion - 1.0027) < 0.0002
+
+    /**
+     * Check if a satellite has likely decayed based on drag and time since epoch.
+     *
+     * @param meanMotion revolutions per day
+     * @param drag first derivative of mean motion / 2 (from TLE line 1)
+     * @param epochDaynum TLE epoch as daynum (days since 31Dec79)
+     * @param currentDaynum current time as daynum
+     */
+    fun hasDecayed(meanMotion: Double, drag: Double, epochDaynum: Double, currentDaynum: Double): Boolean {
+        return epochDaynum + ((16.666666 - meanMotion) / (10.0 * abs(drag))) < currentDaynum
+    }
+
+    // ── Rise/Set finding ──
+
+    /** Rise and set times for a celestial body. */
+    data class RiseSetTimes(
+        val riseTimeMillis: Long,  // 0 if not found
+        val setTimeMillis: Long    // 0 if not found
+    )
+
+    /**
+     * Find the next sunrise and sunset times from [startMillis] for [observer].
+     * Uses elevation threshold of -0.8333° to match the standard civil definition:
+     * upper limb on geometric horizon with standard atmospheric refraction (~0.57°)
+     * and solar semidiameter (~0.27°) corrections applied, matching USNO/timeanddate.com.
+     */
+    fun findSunRiseSet(observer: GeoPos, startMillis: Long): RiseSetTimes {
+        // Standard civil threshold: center elevation when upper limb meets geometric horizon
+        // -0.8333° = standard refraction (~0.5667°) + solar semidiameter (~0.2667°)
+        val threshold = 0.8333
+        var daynum = millisToDaynum(startMillis)
+        var sunPos = getSunPosition(observer, daynumToMillis(daynum))
+
+        // Phase 1: if sun is above threshold, fast-forward to well past sunset into night
+        if (sunPos.elevation > -threshold) {
+            var guard = 0
+            while (sunPos.elevation > -threshold && guard++ < 500) {
+                daynum += 0.008  // fixed ~11.5 min steps past the setting sun
+                sunPos = getSunPosition(observer, daynumToMillis(daynum))
+            }
+            // Now advance until sun is clearly below minimum (deep night)
+            guard = 0
+            while (sunPos.elevation > -12.0 && guard++ < 500) {
+                daynum += 0.02
+                sunPos = getSunPosition(observer, daynumToMillis(daynum))
+            }
+        }
+
+        // Phase 2: advance until sun starts rising toward threshold (elevation increasing)
+        var guard = 0
+        while (sunPos.elevation < -threshold && guard++ < 500) {
+            daynum += 0.008
+            sunPos = getSunPosition(observer, daynumToMillis(daynum))
+        }
+
+        // Phase 3: converge symmetrically on elevation = -threshold (sunrise)
+        var sunrise = 0.0
+        guard = 0
+        while (sunrise == 0.0 && guard++ < 200) {
+            val delta = sunPos.elevation + threshold
+            if (abs(delta) < 0.01) {
+                sunrise = daynum
+            } else {
+                daynum -= 0.004 * delta
+                sunPos = getSunPosition(observer, daynumToMillis(daynum))
+            }
+        }
+        if (sunrise == 0.0) sunrise = daynum
+
+        // Phase 4: fast-forward through the day until sun drops back below threshold.
+        // Start from just after sunrise (small offset) so the sun is clearly above
+        // the threshold. This prevents a bug where Phase 3 converges to a point
+        // slightly below -threshold, causing Phase 4 to skip and Phase 5 to converge
+        // to the same time as sunrise, producing identical sunrise/sunset times.
+        daynum = sunrise + 0.001
+        sunPos = getSunPosition(observer, daynumToMillis(daynum))
+        guard = 0
+        while (sunPos.elevation >= -threshold && guard++ < 500) {
+            daynum += 0.008
+            sunPos = getSunPosition(observer, daynumToMillis(daynum))
+        }
+
+        // Phase 5: converge symmetrically on elevation = -threshold (sunset)
+        var sunset = 0.0
+        guard = 0
+        while (sunset == 0.0 && guard++ < 200) {
+            val delta = sunPos.elevation + threshold
+            if (abs(delta) < 0.01) {
+                sunset = daynum
+            } else {
+                daynum += 0.004 * delta
+                sunPos = getSunPosition(observer, daynumToMillis(daynum))
+            }
+        }
+        if (sunset == 0.0) sunset = daynum
+
+        return RiseSetTimes(daynumToMillis(sunrise), daynumToMillis(sunset))
+    }
+
+    /**
+     * Find the next moonrise and moonset times from [startMillis] for [observer].
+     * Uses the adaptive iteration from PREDICT v2.2.5's PredictMoon().
+     */
+    fun findMoonRiseSet(observer: GeoPos, startMillis: Long): RiseSetTimes {
+        var daynum = millisToDaynum(startMillis)
+        var moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+
+        // If moon is already up, move forward until it sets
+        var guard = 0
+        if (moonPos.elevation > 0) {
+            while (moonPos.elevation > 0 && guard++ < 1000) {
+                daynum += 0.004 * sin(DEG2RAD * (moonPos.elevation + 0.5))
+                moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+            }
+            daynum += 0.4
+            moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+        }
+        // Find moonrise
+        var moonrise = 0.0
+        guard = 0
+        while (moonrise == 0.0 && guard++ < 1000) {
+            if (abs(moonPos.elevation) < 0.03) {
+                moonrise = daynum
+            } else {
+                daynum -= 0.004 * moonPos.elevation
+                moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+            }
+        }
+        if (moonrise == 0.0) moonrise = daynum
+
+        // Find moonset from moonrise
+        daynum = moonrise
+        moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+        guard = 0
+        while (moonPos.elevation > -1 && guard++ < 1000) {
+            daynum += 0.04 * cos(DEG2RAD * (moonPos.elevation + 0.5))
+            moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+        }
+        var moonset = 0.0
+        guard = 0
+        while (moonset == 0.0 && guard++ < 1000) {
+            if (abs(moonPos.elevation) < 0.03) {
+                moonset = daynum
+            } else {
+                daynum += 0.004 * moonPos.elevation
+                moonPos = getMoonPosition(observer, daynumToMillis(daynum))
+            }
+        }
+        if (moonset == 0.0) moonset = daynum
+
+        return RiseSetTimes(daynumToMillis(moonrise), daynumToMillis(moonset))
+    }
+
+    // ── Visual magnitude estimation ──
+
+    /**
+     * Estimate the apparent visual magnitude of a satellite.
+     *
+     * Uses the standard formula from McCants/Heavens-Above:
+     *   apparentMag = stdMag + 5 * log10(range / 1000) - 15 * log10(cos(phaseAngle / 2))
+     *
+     * @param rangeKm slant range from observer to satellite in km
+     * @param phaseAngleDeg Sun-satellite-observer angle in degrees
+     * @param stdMag intrinsic/standard magnitude (default 4.0)
+     * @return estimated apparent visual magnitude
+     */
+    fun estimateVisualMagnitude(rangeKm: Double, phaseAngleDeg: Double, stdMag: Double = 4.0): Double {
+        if (rangeKm <= 0) return stdMag
+        val halfPhaseRad = phaseAngleDeg.toRadians() / 2.0
+        val cosHalfPhase = cos(halfPhaseRad)
+        val phaseTerm = if (cosHalfPhase > 1e-6) -15.0 * log10(cosHalfPhase) else 99.0
+        return stdMag + 5.0 * log10(rangeKm / 1000.0) + phaseTerm
+    }
+
+    /**
+     * Compute the phase angle (Sun-satellite-observer) in degrees.
+     *
+     * @param satPosECI satellite ECI position [x, y, z] in km
+     * @param sunPosECI sun ECI position [x, y, z] in km
+     * @param obsPosECI observer ECI position [x, y, z] in km
+     * @return phase angle in degrees (0 = fully illuminated face toward observer)
+     */
+    fun computePhaseAngle(satPosECI: DoubleArray, sunPosECI: DoubleArray, obsPosECI: DoubleArray): Double {
+        val toSunX = sunPosECI[0] - satPosECI[0]
+        val toSunY = sunPosECI[1] - satPosECI[1]
+        val toSunZ = sunPosECI[2] - satPosECI[2]
+        val toObsX = obsPosECI[0] - satPosECI[0]
+        val toObsY = obsPosECI[1] - satPosECI[1]
+        val toObsZ = obsPosECI[2] - satPosECI[2]
+        val dot = toSunX * toObsX + toSunY * toObsY + toSunZ * toObsZ
+        val magSun = sqrt(toSunX * toSunX + toSunY * toSunY + toSunZ * toSunZ)
+        val magObs = sqrt(toObsX * toObsX + toObsY * toObsY + toObsZ * toObsZ)
+        if (magSun == 0.0 || magObs == 0.0) return 90.0
+        val cosAngle = (dot / (magSun * magObs)).coerceIn(-1.0, 1.0)
+        return acos(cosAngle).toDegrees()
+    }
+
+    // ── Doppler ──
+
+    /**
+     * Compute Doppler shift for a given base frequency and range rate.
+     *
+     * @param frequencyHz base frequency in Hz
+     * @param rangeRateKmS range rate in km/s (negative = approaching)
+     * @return shifted frequency in Hz
+     */
+    fun dopplerShift(frequencyHz: Double, rangeRateKmS: Double): Double {
+        return frequencyHz * (299792.458 - rangeRateKmS) / 299792.458
+    }
+
+    // ── Internal helpers ──
+
+    private fun observerGeodetic(pos: GeoPos): DoubleArray {
+        // [lat_rad, lon_rad, alt_km] — longitude positive east, matching OrbitalObject convention.
+        // LST = thetaGJD(julUtc) + obsGeo[1] = GMST + lon_rad (correct).
+        return doubleArrayOf(pos.latitude * DEG2RAD, pos.longitude * DEG2RAD, pos.altitude / 1000.0)
+    }
+
+    /**
+     * Convert az/el observation to Right Ascension / Declination.
+     * Returns [ra_rad, dec_rad].
+     * Based on Calculate_RADec() from PREDICT v2.2.5 (Escobal method).
+     */
+    private fun calculateRADec(
+        julUtc: Double,
+        targetPos: DoubleArray,
+        targetVel: DoubleArray,
+        obsGeo: DoubleArray
+    ): DoubleArray {
+        val obsSet = computeObsAngles(julUtc, targetPos, targetVel, obsGeo)
+        val az = obsSet[0]
+        val el = obsSet[1]
+        val phi = obsGeo[0]
+        val theta = mod2PI(thetaGJD(julUtc) + obsGeo[1])
+        val sinTheta = sin(theta)
+        val cosTheta = cos(theta)
+        val sinPhi = sin(phi)
+        val cosPhi = cos(phi)
+        val lxh = -cos(az) * cos(el)
+        val lyh = sin(az) * cos(el)
+        val lzh = sin(el)
+        val sx = sinPhi * cosTheta
+        val ex2 = -sinTheta
+        val zx = cosTheta * cosPhi
+        val sy = sinPhi * sinTheta
+        val zy = sinTheta * cosPhi
+        val sz = -cosPhi
+        val lx = sx * lxh + ex2 * lyh + zx * lzh
+        val ly = sy * lxh + cosTheta * lyh + zy * lzh
+        val lz = sz * lxh + 0.0 * lyh + sinPhi * lzh
+        val dec = asin(lz)
+        val cosDelta = sqrt(1.0 - lz * lz)
+        val sinAlpha = ly / cosDelta
+        val cosAlpha = lx / cosDelta
+        val ra = mod2PI(atan2(sinAlpha, cosAlpha))
+        return doubleArrayOf(ra, dec)
+    }
+
+    /**
+     * Compute observer look-angles (az, el, range, rangeRate) to a target at ECI position.
+     * Returns [azimuth_rad, elevation_rad, range_km, rangeRate_km/s].
+     * Azimuth is north-referenced (0=N, π/2=E), matching OrbitalObject's convention.
+     */
+    private fun computeObsAngles(
+        julUtc: Double,
+        targetPos: DoubleArray,
+        targetVel: DoubleArray,
+        obsGeo: DoubleArray // [lat_rad, lon_rad, alt_km]
+    ): DoubleArray {
+        val theta = mod2PI(thetaGJD(julUtc) + obsGeo[1])
+        val c = 1.0 / sqrt(1 + FLAT_FACT * (FLAT_FACT - 2) * sin(obsGeo[0]).pow(2))
+        val sq = (1 - FLAT_FACT).pow(2) * c
+        val achcp = (EARTH_RADIUS * c + obsGeo[2]) * cos(obsGeo[0])
+        val ox = achcp * cos(theta)
+        val oy = achcp * sin(theta)
+        val oz = (EARTH_RADIUS * sq + obsGeo[2]) * sin(obsGeo[0])
+        val ovx = -MFACTOR * oy
+        val ovy = MFACTOR * ox
+
+        val rx = targetPos[0] - ox
+        val ry = targetPos[1] - oy
+        val rz = targetPos[2] - oz
+        val rMag = sqrt(rx * rx + ry * ry + rz * rz)
+        val rvx = targetVel[0] - ovx
+        val rvy = targetVel[1] - ovy
+        val rvz = targetVel[2]
+
+        val sinLat = sin(obsGeo[0])
+        val cosLat = cos(obsGeo[0])
+        val sinTheta = sin(theta)
+        val cosTheta = cos(theta)
+        val topS = sinLat * cosTheta * rx + sinLat * sinTheta * ry - cosLat * rz
+        val topE = -sinTheta * rx + cosTheta * ry
+        val topZ = cosLat * cosTheta * rx + cosLat * sinTheta * ry + sinLat * rz
+
+        // Match north-based convention (0=N, 90=E) used by OrbitalObject.calculateObs
+        // Must use atan(-topE / topS) not atan2(-topE, topS) — they differ in quadrant handling
+        var azim = atan(-topE / topS)
+        if (topS > 0.0) azim += PI
+        if (azim < 0.0) azim += TWO_PI
+        val el = asin(topZ / rMag)
+        val rangeRate = (rx * rvx + ry * rvy + rz * rvz) / rMag
+
+        return doubleArrayOf(azim, el, rMag, rangeRate)
+    }
+
+    private const val MFACTOR = 7.292115E-5
+
+    private fun primeAngle(x: Double) = x - 360.0 * floor(x / 360.0)
+
+    private fun fixAngle(x: Double): Double {
+        var a = x; while (a > TWO_PI) a -= TWO_PI; return a
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/Constants.kt

@@ -21,6 +21,7 @@ const val ASTRONOMICAL_UNIT = 1.49597870691E8
 const val DEG2RAD = 0.017453292519943295
 const val RAD2DEG = 57.29577951308232
 const val EARTH_RADIUS = 6378.137
+const val EARTH_ROT_PER_SID_DAY = 1.00273790934
 const val EPSILON = 1.0E-12
 const val FLAT_FACT = 3.35281066474748E-3
 const val J3_HARMONIC = -2.53881E-6

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/DeepSpaceObject.kt

@@ -97,40 +97,38 @@ class DeepSpaceObject(data: OrbitalData) : OrbitalObject(data) {
     }
 
     internal fun calculateSDP4(tSince: Double) {
-        synchronized(this) {
-            val temp = DoubleArray(12)
-            val xmdf = data.xmo + dsv.xmdot * tSince
-            val tsq = tSince * tSince
-            val templ = t2cof * tsq
-            dsv.xll = xmdf + dsv.xnodp * templ
-            dsv.omgadf = data.omegao + dsv.omgdot * tSince
-            val xnoddf = data.xnodeo + dsv.xnodot * tSince
-            dsv.xnode = xnoddf + xnodcf * tsq
-            val tempa = 1.0 - c1 * tSince
-            val tempe = data.bstar * c4 * tSince
-            dsv.xn = dsv.xnodp
-            dsv.t = tSince
-            deep.dpsec(data)
-            val a = (XKE / dsv.xn).pow(TWO_THIRDS) * tempa * tempa
-            dsv.em -= tempe
-            deep.dpper()
-            val xl = dsv.xll + dsv.omgadf + dsv.xnode
-            val beta = sqrt(1.0 - dsv.em * dsv.em)
-            dsv.xn = XKE / a.pow(1.5)
-            // Long period periodics
-            val axn = dsv.em * cos(dsv.omgadf)
-            temp[0] = invert(a * beta * beta)
-            val xll = temp[0] * xlcof * axn
-            val aynl = temp[0] * aycof
-            val xlt = xl + xll
-            val ayn = dsv.em * sin(dsv.omgadf) + aynl
-            // Solve Kepler's equation
-            val capu = mod2PI(xlt - dsv.xnode)
-            temp[2] = capu
-            converge(temp, axn, ayn, capu)
-            calculatePosAndVel(temp, a, axn, ayn)
-            calculatePhase(xlt, dsv.xnode, dsv.omgadf)
-        }
+        val temp = DoubleArray(12)
+        val xmdf = data.xmo + dsv.xmdot * tSince
+        val tsq = tSince * tSince
+        val templ = t2cof * tsq
+        dsv.xll = xmdf + dsv.xnodp * templ
+        dsv.omgadf = data.omegao + dsv.omgdot * tSince
+        val xnoddf = data.xnodeo + dsv.xnodot * tSince
+        dsv.xnode = xnoddf + xnodcf * tsq
+        val tempa = 1.0 - c1 * tSince
+        val tempe = data.bstar * c4 * tSince
+        dsv.xn = dsv.xnodp
+        dsv.t = tSince
+        deep.dpsec(data)
+        val a = (XKE / dsv.xn).pow(TWO_THIRDS) * tempa * tempa
+        dsv.em -= tempe
+        deep.dpper()
+        val xl = dsv.xll + dsv.omgadf + dsv.xnode
+        val beta = sqrt(1.0 - dsv.em * dsv.em)
+        dsv.xn = XKE / a.pow(1.5)
+        // Long period periodics
+        val axn = dsv.em * cos(dsv.omgadf)
+        temp[0] = invert(a * beta * beta)
+        val xll = temp[0] * xlcof * axn
+        val aynl = temp[0] * aycof
+        val xlt = xl + xll
+        val ayn = dsv.em * sin(dsv.omgadf) + aynl
+        // Solve Kepler's equation
+        val capu = mod2PI(xlt - dsv.xnode)
+        temp[2] = capu
+        converge(temp, axn, ayn, capu)
+        calculatePosAndVel(temp, a, axn, ayn)
+        calculatePhase(xlt, dsv.xnode, dsv.omgadf)
     }
 
     private fun calculatePosAndVel(temp: DoubleArray, a: Double, axn: Double, ayn: Double) {

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/NearEarthObject.kt

@@ -141,53 +141,51 @@ class NearEarthObject(data: OrbitalData) : OrbitalObject(data) {
     }
 
     internal fun calculateSGP4(tSince: Double) {
-        synchronized(this) {
-            val temp = DoubleArray(9)
-            val xmdf = data.xmo + xmdot * tSince
-            val omgadf = data.omegao + omgdot * tSince
-            val xnoddf = data.xnodeo + xnodot * tSince
-            var omega = omgadf
-            var xmp = xmdf
-            val tsq = sqr(tSince)
-            val xnode = xnoddf + xnodcf * tsq
-            val bstar = data.bstar
-            var tempa = 1.0 - c1 * tSince
-            var tempe = bstar * c4 * tSince
-            var templ = t2cof * tsq
-            if (!sgp4Simple) {
-                val delomg = omgcof * tSince
-                val delm = xmcof * ((1.0 + eta * cos(xmdf)).pow(3.0) - delmo)
-                temp[0] = delomg + delm
-                xmp = xmdf + temp[0]
-                omega = omgadf - temp[0]
-                val tcube = tsq * tSince
-                val tfour = tSince * tcube
-                tempa = tempa - d2 * tsq - d3 * tcube - d4 * tfour
-                tempe += bstar * c5 * (sin(xmp) - sinmo)
-                templ += t3cof * tcube + tfour * (t4cof + tSince * t5cof)
-            }
-            val a = aodp * tempa.pow(2.0)
-            val eo = data.eccn
-            val e = eo - tempe
-            val xl = xmp + omega + xnode + xnodp * templ
-            val beta = sqrt(1.0 - e * e)
-            val xn = XKE / a.pow(1.5)
-
-            // Long period periodics
-            val axn = e * cos(omega)
-            temp[0] = invert(a * sqr(beta))
-            val xll = temp[0] * xlcof * axn
-            val aynl = temp[0] * aycof
-            val xlt = xl + xll
-            val ayn = e * sin(omega) + aynl
-
-            // Solve Kepler's equation
-            val capu = mod2PI(xlt - xnode)
-            temp[2] = capu
-            converge(temp, axn, ayn, capu)
-            calculatePosAndVel(temp, xnode, a, xn, axn, ayn)
-            calculatePhase(xlt, xnode, omgadf)
+        val temp = DoubleArray(9)
+        val xmdf = data.xmo + xmdot * tSince
+        val omgadf = data.omegao + omgdot * tSince
+        val xnoddf = data.xnodeo + xnodot * tSince
+        var omega = omgadf
+        var xmp = xmdf
+        val tsq = tSince * tSince
+        val xnode = xnoddf + xnodcf * tsq
+        val bstar = data.bstar
+        var tempa = 1.0 - c1 * tSince
+        var tempe = bstar * c4 * tSince
+        var templ = t2cof * tsq
+        if (!sgp4Simple) {
+            val delomg = omgcof * tSince
+            val delm = xmcof * ((1.0 + eta * cos(xmdf)).pow(3.0) - delmo)
+            temp[0] = delomg + delm
+            xmp = xmdf + temp[0]
+            omega = omgadf - temp[0]
+            val tcube = tsq * tSince
+            val tfour = tSince * tcube
+            tempa = tempa - d2 * tsq - d3 * tcube - d4 * tfour
+            tempe += bstar * c5 * (sin(xmp) - sinmo)
+            templ += t3cof * tcube + tfour * (t4cof + tSince * t5cof)
         }
+        val a = aodp * tempa * tempa
+        val eo = data.eccn
+        val e = eo - tempe
+        val xl = xmp + omega + xnode + xnodp * templ
+        val beta = sqrt(1.0 - e * e)
+        val xn = XKE / a.pow(1.5)
+
+        // Long period periodics
+        val axn = e * cos(omega)
+        temp[0] = invert(a * sqr(beta))
+        val xll = temp[0] * xlcof * axn
+        val aynl = temp[0] * aycof
+        val xlt = xl + xll
+        val ayn = e * sin(omega) + aynl
+
+        // Solve Kepler's equation
+        val capu = mod2PI(xlt - xnode)
+        temp[2] = capu
+        converge(temp, axn, ayn, capu)
+        calculatePosAndVel(temp, xnode, a, xn, axn, ayn)
+        calculatePhase(xlt, xnode, omgadf)
     }
 
     private fun calculatePosAndVel(

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/OrbitalData.kt

@@ -27,7 +27,8 @@ data class OrbitalData(
     val argper: Double,
     val meanan: Double,
     val catnum: Int,
-    val bstar: Double
+    val bstar: Double,
+    val ndot: Double = 0.0
 ) {
     val xincl: Double = incl * DEG2RAD
     val xnodeo: Double = raan * DEG2RAD
@@ -37,4 +38,29 @@ data class OrbitalData(
     val orbitalPeriod: Double = MIN_PER_DAY / meanmo
     val isDeepSpace: Boolean = orbitalPeriod >= 225.0 // NearEarth (period < 225 min) or DeepSpace (period >= 225 min)
     fun getObject(): OrbitalObject = if (isDeepSpace) DeepSpaceObject(this) else NearEarthObject(this)
+
+    /** Check if satellite has likely decayed by the given time. */
+    fun hasDecayed(currentTimeMillis: Long): Boolean {
+        if (ndot == 0.0) return false
+        val currentDaynum = (currentTimeMillis - 315446400000L) / 86400000.0
+        val epochDaynum = epochToDaynum(epoch)
+        return CelestialComputer.hasDecayed(meanmo, ndot, epochDaynum, currentDaynum)
+    }
+
+    private fun epochToDaynum(epoch: Double): Double {
+        var year = kotlin.math.floor(epoch * 1E-3)
+        val day = (epoch * 1E-3 - year) * 1000.0
+        year = if (year < 57) year + 2000 else year + 1900
+        // daynum = days since 31 Dec 1979, Julian date of 31Dec79 = 2444238.5
+        val jan1Jd = julianDateOfYear(year)
+        return jan1Jd + day - 2444238.5
+    }
+
+    private fun julianDateOfYear(theYear: Double): Double {
+        val aYear = theYear - 1
+        val a = kotlin.math.floor(aYear / 100).toLong()
+        val b = 2 - a + a / 4
+        val i = kotlin.math.floor(365.25 * aYear).toLong()
+        return i + (30.6001 * 14).toLong() + 1720994.5 + b
+    }
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/OrbitalMath.kt

@@ -0,0 +1,141 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.predict
+
+import kotlin.math.abs
+import kotlin.math.atan2
+import kotlin.math.cos
+import kotlin.math.floor
+import kotlin.math.sin
+import kotlin.math.sqrt
+
+// ── Shared orbital math utilities ──
+// Used by both CelestialComputer (sun/moon/celestial) and OrbitalObject (SGP4/SDP4).
+// Package-internal — not part of the public API.
+
+/**
+ * Greenwich Mean Sidereal Time from Julian Date, in radians [0, 2π).
+ * Identical algorithm used in PREDICT v2.2.5 for both solar and satellite calculations.
+ */
+internal fun thetaGJD(jd: Double): Double {
+    val ut = fraction(jd + 0.5)
+    val aJD = jd - ut
+    val tu = (aJD - 2451545.0) / 36525.0
+    var gmst = 24110.54841 + tu * (8640184.812866 + tu * (0.093104 - tu * 6.2E-6))
+    gmst = modulus(gmst + SEC_PER_DAY * EARTH_ROT_PER_SID_DAY * ut, SEC_PER_DAY)
+    return TWO_PI * gmst / SEC_PER_DAY
+}
+
+/** Fractional part of [arg]. */
+internal fun fraction(arg: Double): Double = arg - floor(arg)
+
+/** Modulo: returns [arg1] mod [arg2], result always in [0, arg2). */
+internal fun modulus(arg1: Double, arg2: Double): Double {
+    var r = arg1
+    val i = floor(r / arg2).toInt()
+    r -= i * arg2
+    if (r < 0.0) r += arg2
+    return r
+}
+
+/** Reduce [value] to [0, 2π). */
+internal fun mod2PI(value: Double): Double {
+    var r = value
+    val i = (r / TWO_PI).toInt()
+    r -= i * TWO_PI
+    if (r < 0.0) r += TWO_PI
+    return r
+}
+
+/**
+ * Delta-ET: difference between Universal Time and Ephemeris Time (seconds).
+ * Based on least-squares fit from 1950 to 1991 (PREDICT v2.2.5).
+ */
+internal fun deltaET(year: Double): Double =
+    26.465 + 0.747622 * (year - 1950) + 1.886913 * sin(TWO_PI * (year - 1975) / 33)
+
+/**
+ * Convert Unix epoch milliseconds to daynum (days since 31 Dec 1979 00:00:00 UTC).
+ */
+internal fun millisToDaynum(timeMillis: Long): Double =
+    (timeMillis - 315446400000L) / 86400000.0
+
+/** Convert daynum back to Unix epoch milliseconds. */
+internal fun daynumToMillis(daynum: Double): Long =
+    ((daynum + 3651.0) * 86400000.0).toLong()
+
+/**
+ * Compute the Sun's ECI position vector at [julUtc] (Julian UTC).
+ * Returns [x, y, z, magnitude] in km.
+ * Based on Calculate_Solar_Position() / FindSun() from PREDICT v2.2.5.
+ */
+internal fun solarPositionECI(julUtc: Double): DoubleArray {
+    val mjd = julUtc - 2415020.0
+    val year = 1900 + mjd / 365.25
+    val t = (mjd + deltaET(year) / SEC_PER_DAY) / 36525.0
+    val mDeg = mod360(358.47583 + mod360(35999.04975 * t) - (0.000150 + 0.0000033 * t) * t * t)
+    val m = mDeg * DEG2RAD
+    val lDeg = mod360(279.69668 + mod360(36000.76892 * t) + 0.0003025 * t * t)
+    val l = lDeg * DEG2RAD
+    val e = 0.01675104 - (0.0000418 + 0.000000126 * t) * t
+    val cDeg = (1.919460 - (0.004789 + 0.000014 * t) * t) * sin(m) +
+        (0.020094 - 0.000100 * t) * sin(2 * m) + 0.000293 * sin(3 * m)
+    val c = cDeg * DEG2RAD
+    val oDeg = mod360(259.18 - 1934.142 * t)
+    val o = oDeg * DEG2RAD
+    val lsa = mod2PI(l + c - (0.00569 - 0.00479 * sin(o)) * DEG2RAD)
+    val nu = mod2PI(m + c)
+    var r = 1.0000002 * (1.0 - e * e) / (1.0 + e * cos(nu))
+    val epsDeg = 23.452294 - (0.0130125 + (0.00000164 - 0.000000503 * t) * t) * t + 0.00256 * cos(o)
+    val eps = epsDeg * DEG2RAD
+    r *= ASTRONOMICAL_UNIT
+    return doubleArrayOf(r * cos(lsa), r * sin(lsa) * cos(eps), r * sin(lsa) * sin(eps), r)
+}
+
+/**
+ * Convert ECI position [eciPos] = [x, y, z] (km) to geodetic [lat_rad, lon_rad, alt_km].
+ * Based on Calculate_LatLonAlt() from PREDICT v2.2.5.
+ */
+internal fun eciToGeodetic(julUtc: Double, eciPos: DoubleArray): DoubleArray {
+    val thetaPos = atan2(eciPos[1], eciPos[0])
+    val lon = mod2PI(thetaPos - thetaGJD(julUtc))
+    val r = sqrt(eciPos[0] * eciPos[0] + eciPos[1] * eciPos[1])
+    val e2 = FLAT_FACT * (2.0 - FLAT_FACT)
+    var lat = atan2(eciPos[2], r)
+    var phi: Double
+    var c: Double
+    var i = 0
+    do {
+        phi = lat
+        c = 1.0 / sqrt(1.0 - e2 * sin(phi) * sin(phi))
+        lat = atan2(eciPos[2] + EARTH_RADIUS * c * e2 * sin(phi), r)
+    } while (i++ < 10 && abs(lat - phi) >= 1E-10)
+    val alt = r / cos(lat) - EARTH_RADIUS * c
+    if (lat > PI_2) lat -= TWO_PI
+    return doubleArrayOf(lat, lon, alt)
+}
+
+// Private helpers
+
+private fun mod360(x: Double): Double {
+    var r = x
+    val i = (r / 360.0).toInt()
+    r -= i * 360.0
+    if (r < 0.0) r += 360.0
+    return r
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/OrbitalObject.kt

@@ -42,6 +42,27 @@ abstract class OrbitalObject(val data: OrbitalData) {
     var qoms24 = 0.0
     var s4 = 0.0
 
+    // Pre-allocated reusable vectors to avoid GC pressure in hot loops
+    private val obsPos = Vector4()
+    private val obsVel = Vector4()
+    private val rangeVector = Vector4()
+    private val rgvelVector = Vector4()
+    private val squintVector = Vector4()
+
+    // Cached observer position data to avoid recalculation when observer hasn't moved
+    private var cachedGsLat = Double.NaN
+    private var cachedGsLon = Double.NaN
+    private var cachedGsAlt = Double.NaN
+    private var cachedSinLat = 0.0
+    private var cachedCosLat = 0.0
+    private var cachedObsC = 0.0
+    private var cachedObsSq = 0.0
+    private var cachedObsAchFactor = 0.0
+    private var cachedObsZFactor = 0.0
+
+    // Cache for julian epoch to avoid recomputing every call
+    private val julEpoch: Double = juliandDateOfEpoch(data.epoch)
+
     fun willBeSeen(pos: GeoPos): Boolean {
         return if (data.meanmo < 1e-8) false
         else {
@@ -57,15 +78,13 @@ abstract class OrbitalObject(val data: OrbitalData) {
         orbitalPos = OrbitalPos()
         // Date/time at which the position and velocity were calculated
         julUTC = calcCurrentDaynum(time) + 2444238.5
-        // Convert satellite's epoch time to Julian and calculate time since epoch in minutes
-        val julEpoch = juliandDateOfEpoch(data.epoch)
+        // Calculate time since epoch in minutes
         val tsince = (julUTC - julEpoch) * MIN_PER_DAY
         calculateSDP4orSGP4(tsince)
         // Scale position and velocity vectors to km and km/sec
         convertSatState(position, velocity)
         // Calculate velocity of satellite
         magnitude(velocity)
-        val squintVector = Vector4()
         // Angles in rads, dist in km, vel in km/S. Calculate sat Az, El, Range and Range-rate.
         calculateObs(julUTC, position, velocity, pos, squintVector)
         calculateLatLonAlt(julUTC)
@@ -75,6 +94,38 @@ abstract class OrbitalObject(val data: OrbitalData) {
         return orbitalPos
     }
 
+    /**
+     * Lightweight elevation-only check for pass finding. Avoids full lat/lon/alt,
+     * eclipse, and squint calculations that aren't needed when just searching for
+     * horizon crossings.
+     */
+    fun getElevation(pos: GeoPos, time: Long): Double {
+        julUTC = calcCurrentDaynum(time) + 2444238.5
+        val tsince = (julUTC - julEpoch) * MIN_PER_DAY
+        calculateSDP4orSGP4(tsince)
+        convertSatState(position, velocity)
+        magnitude(velocity)
+        calculateObs(julUTC, position, velocity, pos, squintVector)
+        return orbitalPos.elevation
+    }
+
+    /**
+     * Full position calculation that also populates azimuth, altitude, etc.
+     * Used when we need all fields (AOS/LOS refinement, track computation).
+     */
+    fun getFullPosition(pos: GeoPos, time: Long): OrbitalPos {
+        orbitalPos = OrbitalPos()
+        julUTC = calcCurrentDaynum(time) + 2444238.5
+        val tsince = (julUTC - julEpoch) * MIN_PER_DAY
+        calculateSDP4orSGP4(tsince)
+        convertSatState(position, velocity)
+        magnitude(velocity)
+        calculateObs(julUTC, position, velocity, pos, squintVector)
+        calculateLatLonAlt(julUTC)
+        orbitalPos.time = time
+        return orbitalPos
+    }
+
     private fun calcCurrentDaynum(now: Long): Double {
         val then = 315446400000 // time in millis on 31Dec79 00:00:00 UTC (daynum 0)
         return (now - then) / 1000.0 / 60.0 / 60.0 / 24.0
@@ -117,38 +168,34 @@ abstract class OrbitalObject(val data: OrbitalData) {
         gsPos: GeoPos,
         squintVector: Vector4
     ) {
-        val obsPos = Vector4()
-        val obsVel = Vector4()
-        val range = Vector4()
-        val rgvel = Vector4()
         calculateUserPosVel(julianUTC, gsPos, obsPos, obsVel)
-        range.setXYZ(
+        rangeVector.setXYZ(
             positionVector.x - obsPos.x,
             positionVector.y - obsPos.y,
             positionVector.z - obsPos.z
         )
         // Save these values globally for calculating squint angles later
-        squintVector.setXYZ(range.x, range.y, range.z)
-        rgvel.setXYZ(
+        squintVector.setXYZ(rangeVector.x, rangeVector.y, rangeVector.z)
+        rgvelVector.setXYZ(
             velocityVector.x - obsVel.x,
             velocityVector.y - obsVel.y,
             velocityVector.z - obsVel.z
         )
-        magnitude(range)
-        val sinLat = sin(DEG2RAD * gsPos.latitude)
-        val cosLat = cos(DEG2RAD * gsPos.latitude)
+        magnitude(rangeVector)
+        val sinLat = cachedSinLat
+        val cosLat = cachedCosLat
         val sinTheta = sin(gsPosTheta)
         val cosTheta = cos(gsPosTheta)
-        val topS = sinLat * cosTheta * range.x + sinLat * sinTheta * range.y - cosLat * range.z
-        val topE = -sinTheta * range.x + cosTheta * range.y
-        val topZ = cosLat * cosTheta * range.x + cosLat * sinTheta * range.y + sinLat * range.z
+        val topS = sinLat * cosTheta * rangeVector.x + sinLat * sinTheta * rangeVector.y - cosLat * rangeVector.z
+        val topE = -sinTheta * rangeVector.x + cosTheta * rangeVector.y
+        val topZ = cosLat * cosTheta * rangeVector.x + cosLat * sinTheta * rangeVector.y + sinLat * rangeVector.z
         var azim = atan(-topE / topS)
         if (topS > 0.0) azim += PI
         if (azim < 0.0) azim += TWO_PI
         orbitalPos.azimuth = azim
-        orbitalPos.elevation = asin(topZ / range.w)
-        orbitalPos.distance = range.w
-        orbitalPos.distanceRate = dot(range, rgvel) / range.w
+        orbitalPos.elevation = asin(topZ / rangeVector.w)
+        orbitalPos.distance = rangeVector.w
+        orbitalPos.distanceRate = dot(rangeVector, rgvelVector) / rangeVector.w
         var elevation = orbitalPos.elevation / TWO_PI * 360.0
         if (elevation > 90) elevation = 180 - elevation
         orbitalPos.aboveHorizon = elevation - 0 > EPSILON
@@ -163,12 +210,24 @@ abstract class OrbitalObject(val data: OrbitalData) {
     ) {
         val mFactor = 7.292115E-5
         gsPosTheta = mod2PI(thetaGJD(time) + DEG2RAD * gsPos.longitude)
-        val c = invert(sqrt(1.0 + FLAT_FACT * (FLAT_FACT - 2) * sqr(sin(DEG2RAD * gsPos.latitude))))
-        val sq = sqr(1.0 - FLAT_FACT) * c
-        val achcp = (EARTH_RADIUS * c + gsPos.altitude / 1000.0) * cos(DEG2RAD * gsPos.latitude)
+
+        // Cache trig and position factors when observer position changes
+        if (gsPos.latitude != cachedGsLat || gsPos.longitude != cachedGsLon || gsPos.altitude != cachedGsAlt) {
+            cachedGsLat = gsPos.latitude
+            cachedGsLon = gsPos.longitude
+            cachedGsAlt = gsPos.altitude
+            cachedSinLat = sin(DEG2RAD * gsPos.latitude)
+            cachedCosLat = cos(DEG2RAD * gsPos.latitude)
+            cachedObsC = invert(sqrt(1.0 + FLAT_FACT * (FLAT_FACT - 2) * sqr(cachedSinLat)))
+            cachedObsSq = sqr(1.0 - FLAT_FACT) * cachedObsC
+            cachedObsAchFactor = (EARTH_RADIUS * cachedObsC + gsPos.altitude / 1000.0) * cachedCosLat
+            cachedObsZFactor = (EARTH_RADIUS * cachedObsSq + gsPos.altitude / 1000.0) * cachedSinLat
+        }
+
         obsPos.setXYZ(
-            achcp * cos(gsPosTheta), achcp * sin(gsPosTheta),
-            (EARTH_RADIUS * sq + gsPos.altitude / 1000.0) * sin(DEG2RAD * gsPos.latitude)
+            cachedObsAchFactor * cos(gsPosTheta),
+            cachedObsAchFactor * sin(gsPosTheta),
+            cachedObsZFactor
         )
         obsVel.setXYZ(-mFactor * obsPos.y, mFactor * obsPos.x, 0.0)
         magnitude(obsPos)
@@ -255,14 +314,8 @@ abstract class OrbitalObject(val data: OrbitalData) {
         return 1.0 / value
     }
 
-    // Calculates the modulus of 2 * PI
-    internal fun mod2PI(value: Double): Double {
-        var retVal = value
-        val i = (retVal / TWO_PI).toInt()
-        retVal -= i * TWO_PI
-        if (retVal < 0.0) retVal += TWO_PI
-        return retVal
-    }
+    // Delegates to package-level mod2PI in OrbitalMath.kt
+    internal fun mod2PI(value: Double): Double = com.rtbishop.look4sat.core.domain.predict.mod2PI(value)
 
     // Solves Keplers' Equation
     internal fun converge(temp: DoubleArray, axn: Double, ayn: Double, capu: Double) {
@@ -364,19 +417,8 @@ abstract class OrbitalObject(val data: OrbitalData) {
         return acos(dot(v1, v2) / (v1.w * v2.w))
     }
 
-    /**
-     * The function Delta_ET has been added to allow calculations on the
-     * position of the sun. It provides the difference between UT (approximately
-     * the same as UTC) and ET (now referred to as TDT) This function is based
-     * on a least squares fit of data from 1950 to 1991 and will need to be
-     * updated periodically.
-     *
-     * Values determined using data from 1950-1991 in the 1990 Astronomical
-     * Almanac. See DELTA_ET.WQ1 for details.
-     */
-    private fun deltaEt(year: Double): Double {
-        return 26.465 + 0.747622 * (year - 1950) + (1.886913 * sin(TWO_PI * (year - 1975) / 33))
-    }
+    // Delegates to package-level deltaET in OrbitalMath.kt
+    private fun deltaEt(year: Double): Double = deltaET(year)
 
     private fun radians(degrees: Double): Double {
         return degrees * DEG2RAD
@@ -387,23 +429,13 @@ abstract class OrbitalObject(val data: OrbitalData) {
         return v1.x * v2.x + v1.y * v2.y + v1.z * v2.z
     }
 
-    // Returns fractional part of double argument
-    private fun fraction(arg: Double): Double {
-        return arg - floor(arg)
-    }
-
     // Calculates scalar magnitude of a vector4 argument
     private fun magnitude(v: Vector4) {
         v.w = sqrt(sqr(v.x) + sqr(v.y) + sqr(v.z))
     }
 
-    private fun modulus(arg1: Double, arg2: Double = SEC_PER_DAY): Double {
-        var returnValue = arg1
-        val i = floor(returnValue / arg2).toInt()
-        returnValue -= i * arg2
-        if (returnValue < 0.0) returnValue += arg2
-        return returnValue
-    }
+    private fun modulus(arg1: Double, arg2: Double = SEC_PER_DAY): Double =
+        com.rtbishop.look4sat.core.domain.predict.modulus(arg1, arg2)
 
     // Multiplies the vector v1 by the scalar k
     private fun scaleVector(k: Double, v: Vector4) {
@@ -411,13 +443,6 @@ abstract class OrbitalObject(val data: OrbitalData) {
         magnitude(v)
     }
 
-    private fun thetaGJD(theJD: Double): Double {
-        val earthRotPerSidDay = 1.00273790934
-        val ut = fraction(theJD + 0.5)
-        val aJD = theJD - ut
-        val tu = (aJD - 2451545.0) / 36525.0
-        var gmst = 24110.54841 + tu * (8640184.812866 + tu * (0.093104 - tu * 6.2E-6))
-        gmst = modulus(gmst + SEC_PER_DAY * earthRotPerSidDay * ut)
-        return TWO_PI * gmst / SEC_PER_DAY
-    }
+    // Delegates to package-level thetaGJD in OrbitalMath.kt
+    private fun thetaGJD(theJD: Double): Double = com.rtbishop.look4sat.core.domain.predict.thetaGJD(theJD)
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/OrbitalPass.kt

@@ -25,9 +25,10 @@ data class OrbitalPass(
     val altitude: Int = 1000,
     val maxElevation: Double = 75.0,
     val orbitalObject: OrbitalObject,
-    var progress: Float = 0.0f
+    val progress: Float = 0.0f,
+    val hasDecayed: Boolean = false
 ) {
     val catNum: Int = orbitalObject.data.catnum
-    val name: String = orbitalObject.data.name
+    val name: String = if (hasDecayed) "${orbitalObject.data.name} (decayed?)" else orbitalObject.data.name
     val isDeepSpace: Boolean = orbitalObject.data.isDeepSpace
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/predict/OrbitalPos.kt

@@ -21,7 +21,6 @@ import kotlin.math.acos
 import kotlin.math.asin
 import kotlin.math.atan2
 import kotlin.math.cos
-import kotlin.math.pow
 import kotlin.math.sin
 import kotlin.math.sqrt
 
@@ -50,23 +49,30 @@ data class OrbitalPos(
     }
 
     fun getOrbitalVelocity(): Double {
-        val earthG = 6.674 * 10.0.pow(-11)
-        val earthM = 5.98 * 10.0.pow(24)
-        val radius = 6.37 * 10.0.pow(6) + altitude * 10.0.pow(3)
-        return sqrt(earthG * earthM / radius) / 1000
+        val radius = EARTH_RADIUS_M + altitude * 1000.0
+        return sqrt(GM_EARTH / radius) / 1000.0
     }
 
     fun getRangeCircle(): List<GeoPos> {
-        val rangeCirclePoints = mutableListOf<GeoPos>()
-        val beta = acos(EARTH_RADIUS / (EARTH_RADIUS + altitude)) // * EARTH_RADIUS = radiusKm
+        val pointCount = 721
+        val rangeCirclePoints = ArrayList<GeoPos>(pointCount)
+        val beta = acos(EARTH_RADIUS / (EARTH_RADIUS + altitude))
+        val sinLat = sin(latitude)
+        val cosLat = cos(latitude)
+        val cosBeta = cos(beta)
+        val sinBeta = sin(beta)
         for (azimuth in 0..720) {
             val rads = azimuth * DEG2RAD
-            val lat = asin(sin(latitude) * cos(beta) + (cos(latitude) * sin(beta) * cos(rads)))
-            val lon = (longitude + atan2(
-                sin(rads) * sin(beta) * cos(latitude), cos(beta) - sin(latitude) * sin(lat)
-            ))
+            val lat = asin(sinLat * cosBeta + cosLat * sinBeta * cos(rads))
+            val lon = longitude + atan2(sin(rads) * sinBeta * cosLat, cosBeta - sinLat * sin(lat))
             rangeCirclePoints.add(GeoPos(lat * RAD2DEG, lon * RAD2DEG))
         }
         return rangeCirclePoints
     }
+
+    companion object {
+        // Pre-computed constants for orbital velocity calculation
+        private const val GM_EARTH = 3.986004418E14 // m^3/s^2
+        private const val EARTH_RADIUS_M = 6.37E6 // meters
+    }
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IAmSatRepository.kt

@@ -0,0 +1,23 @@
+package com.rtbishop.look4sat.core.domain.repository
+
+import com.rtbishop.look4sat.core.domain.model.AmSatReportSubmission
+import com.rtbishop.look4sat.core.domain.model.AmSatReportSubmitResult
+import com.rtbishop.look4sat.core.domain.model.SatStatusPage
+
+/** AMSAT satellite status data source */
+interface IAmSatRepository {
+    /** Cached AMSAT status page for the current foreground session, if any. */
+    fun getCachedStatus(): SatStatusPage?
+
+    /** Fetch and parse the AMSAT status page; null on failure. */
+    suspend fun fetchStatus(forceRefresh: Boolean = false): SatStatusPage?
+
+    /** Warm the foreground-session cache without forcing a network reload. */
+    suspend fun prefetchStatus()
+
+    /** Clear the foreground-session status cache. */
+    fun clearStatusCache()
+
+    /** Submit a public AMSAT satellite status report. */
+    suspend fun submitReport(submission: AmSatReportSubmission): AmSatReportSubmitResult
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IDatabaseRepo.kt

@@ -18,8 +18,8 @@
 package com.rtbishop.look4sat.core.domain.repository
 
 interface IDatabaseRepo {
-    suspend fun updateTLEFromFile(uri: String)
-    suspend fun updateTransceiversFromFile(uri: String)
+    suspend fun updateTLEFromFile(uri: String): Int
+    suspend fun updateTransceiversFromFile(uri: String): Int
     suspend fun updateFromRemote()
     suspend fun clearAllData()
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/ILoTWRepository.kt

@@ -0,0 +1,38 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.repository
+
+/** Fetches confirmed gridsquares directly from ARRL LoTW. */
+interface ILoTWRepository {
+
+    /**
+     * Fetch all confirmed (QSL_RCVD=Y) gridsquares for the given LoTW account.
+     * Returns the 4-char grid set with an explicit failure cause on error.
+     */
+    suspend fun fetchConfirmedGrids(callsign: String, password: String): LoTWResult
+
+    /**
+     * Same report, but keeps the per-QSO detail of every confirmed satellite
+     * QSO (call / time / satellite / mode / bands), grouped by worked 4-char
+     * gridsquare. Failure cause is kept explicit.
+     */
+    suspend fun fetchConfirmedGridQsos(
+        callsign: String,
+        password: String
+    ): LoTWResult
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IMainContainer.kt

@@ -1,8 +1,28 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
 package com.rtbishop.look4sat.core.domain.repository
-
+import com.rtbishop.look4sat.core.domain.model.SatRadio
 import com.rtbishop.look4sat.core.domain.usecase.IAddToCalendar
+import com.rtbishop.look4sat.core.domain.usecase.IAudioCapture
+import com.rtbishop.look4sat.core.domain.usecase.ISaveImage
 import com.rtbishop.look4sat.core.domain.usecase.IShowToast
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.StateFlow
 
 interface IMainContainer {
     val appScope: CoroutineScope
@@ -10,13 +30,43 @@ interface IMainContainer {
     val selectionRepo: ISelectionRepo
     val satelliteRepo: ISatelliteRepo
     val databaseRepo: IDatabaseRepo
+    val amSatRepo: IAmSatRepository
+    val updateRepo: IUpdateRepository
+    val wavelogRepo: IWavelogRepository
+    val lotwRepo: com.rtbishop.look4sat.core.domain.repository.ILoTWRepository
+    val radioTrackingService: IRadioTrackingService
+    val mutualPassData: StateFlow<MutualPassData>
+    fun setMutualPassData(data: MutualPassData)
     fun provideAddToCalendar(): IAddToCalendar
     fun provideShowToast(): IShowToast
-    fun provideBluetoothReporter(): IReporterRepo<WithoutExtParams>
-    fun provideNetworkReporter(): IReporterRepo<ExtendedParams>
+    fun provideBluetoothReporter(): IReporter
+    fun provideNetworkReporter(): IReporter
     fun provideSensorsRepo(): ISensorsRepo
+    fun provideTxRadioController(): IRadioController
+    fun provideRxRadioController(): IRadioController
+    fun provideAudioCapture(): IAudioCapture
+    fun provideSaveImage(): ISaveImage
 }
 
+data class MutualPassData(
+    val samples: List<Pair<Long, Pair<Double, Double>>> = emptyList(),
+    val trackSamples: List<TrackSampleData> = emptyList(),
+    val startTime: Long = 0L,
+    val endTime: Long = 0L,
+    val maxElev: Double = 10.0,
+    val labelA: String = "你",
+    val labelB: String = "友台"
+)
+
+/** Minimal track sample for cross-module sharing (angles in degrees). */
+data class TrackSampleData(
+    val time: Long = 0L,
+    val azimuthA: Double,
+    val elevationA: Double,
+    val azimuthB: Double,
+    val elevationB: Double
+)
+
 interface IContainerProvider {
     fun getMainContainer(): IMainContainer
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IRadioController.kt

@@ -0,0 +1,88 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.repository
+
+interface IRadioController {
+
+    val isConnected: Boolean
+
+    suspend fun connect(): Boolean
+
+    suspend fun disconnect()
+
+    suspend fun setFrequency(frequencyHz: Long): Boolean
+
+    suspend fun setMode(mode: String): Boolean
+
+    suspend fun setCtcssMode(enabled: Boolean): Boolean
+
+    suspend fun setCtcssTone(toneHz: Double): Boolean
+
+    suspend fun readFrequencyAndMode(): Pair<Long, String>?
+
+    suspend fun pttOn(): Boolean
+
+    suspend fun pttOff(): Boolean
+
+    // ── Extended operations (IC-705 / CI-V) ──────────────────────────────
+
+    /**
+     * Select the band matching [frequencyHz] via the band stacking register.
+     * Must be called before [setFrequency] and [setMode] when first tracking.
+     * Default: no-op (Yaesu radios auto-switch band via frequency).
+     */
+    suspend fun setBand(frequencyHz: Long): Boolean = false
+
+    /**
+     * Select the active VFO.
+     * @param vfoA true → VFO-A (main/RX), false → VFO-B (sub/TX in split).
+     */
+    suspend fun setVfo(vfoA: Boolean): Boolean = false
+
+    /**
+     * Enable or disable SPLIT mode (TX on sub-VFO, RX on main VFO).
+     * Default: not supported.
+     */
+    suspend fun setSplitMode(enabled: Boolean): Boolean = false
+
+    /**
+     * Set the frequency of the currently active VFO (IC-705: CMD 0x25 sub 0x00).
+     * Default: delegates to [setFrequency].
+     */
+    suspend fun setWorkingFrequency(frequencyHz: Long): Boolean = setFrequency(frequencyHz)
+
+    /**
+     * Set the frequency of the inactive/TX VFO (IC-705: CMD 0x25 sub 0x01).
+     * Sent every tracking cycle alongside [setWorkingFrequency] in split mode.
+     * Default: delegates to [setWorkingFrequency].
+     */
+    suspend fun setTxVfoFrequency(frequencyHz: Long): Boolean = setWorkingFrequency(frequencyHz)
+
+    /**
+     * Read the frequency of the currently active VFO (IC-705: CMD 0x25 sub 0x00).
+     * Default: delegates to [readFrequencyAndMode].
+     */
+    suspend fun readWorkingFrequency(): Long? = readFrequencyAndMode()?.first
+
+    /**
+     * Read the frequency of the inactive/TX VFO (IC-705: CMD 0x25 sub 0x01).
+     * Used for tuning detection in split mode.
+     * Default: delegates to [readWorkingFrequency].
+     */
+    suspend fun readTxVfoFrequency(): Long? = readWorkingFrequency()
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IRadioTrackingService.kt

@@ -0,0 +1,55 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.repository
+
+import com.rtbishop.look4sat.core.domain.model.SatRadio
+import com.rtbishop.look4sat.core.domain.predict.OrbitalObject
+import com.rtbishop.look4sat.core.domain.predict.OrbitalPass
+import kotlinx.coroutines.flow.StateFlow
+
+data class RadioTrackingState(
+    val isActive: Boolean = false,
+    val txConnected: Boolean = false,
+    val rxConnected: Boolean = false,
+    val txFrequencyHz: Long? = null,
+    val rxFrequencyHz: Long? = null,
+    val txMode: String? = null,
+    val rxMode: String? = null,
+    val ctcssTone: Double? = null,
+    val txBaseFrequencyHz: Long? = null,
+    val selectedTransponder: SatRadio? = null,
+    val currentPass: OrbitalPass? = null,
+    val azimuth: Double = 0.0,
+    val elevation: Double = 0.0,
+    val distance: Double = 0.0,
+    val errorMessage: String? = null
+)
+
+interface IRadioTrackingService {
+    val state: StateFlow<RadioTrackingState>
+
+    suspend fun connectRadios()
+    suspend fun disconnectRadios()
+    fun startTracking(pass: OrbitalPass, transponder: SatRadio, txBaseFreqHz: Long?)
+    fun stopTracking()
+    fun setTransponder(transponder: SatRadio)
+    fun setTxBaseFrequency(frequencyHz: Long)
+    fun adjustTxBaseFrequency(deltaHz: Long)
+    fun setCtcssTone(toneHz: Double?)
+    fun setMode(txMode: String, rxMode: String)
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IReporterRepo.kt

@@ -17,18 +17,7 @@
  */
 package com.rtbishop.look4sat.core.domain.repository
 
-interface IReporterParams
-
-interface IReporterRepo<T : IReporterParams> {
-    fun isConnected(service: BtService): Boolean
-    fun isConnecting(service: BtService): Boolean
-    fun connect(service: BtService, deviceId: String)
-    fun reportRotation(format: String, azimuth: Double, elevation: Double, params: T)
-    fun reportFrequency(format: String, frequency: Long, params: T)
+interface IReporter {
+    fun reportRotation(format: String, azimuth: Double, elevation: Double)
+    fun reportFrequency(format: String, frequency: Long)
 }
-
-data class ExtendedParams(val server: String, val port: Int) : IReporterParams
-
-data class WithoutExtParams(val dummy: Int) : IReporterParams
-
-enum class BtService { ROTATOR, FREQUENCY }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/ISatelliteRepo.kt

@@ -25,13 +25,44 @@ import com.rtbishop.look4sat.core.domain.predict.OrbitalPos
 import kotlinx.coroutines.flow.StateFlow
 
 interface ISatelliteRepo {
-    val passes: StateFlow<List<OrbitalPass>>
+    /** All selected OrbitalObjects, updated when the selection changes. */
     val satellites: StateFlow<List<OrbitalObject>>
-    suspend fun getRadiosWithId(id: Int): List<SatRadio>
+
+    /** Raw calculated passes (without live progress). Updated on selection/filter change. */
+    val passes: StateFlow<List<OrbitalPass>>
+
+    /** Whether the repo is currently calculating passes. */
+    val isCalculating: StateFlow<Boolean>
+
+    /** Currently selected pass (catNum + aosTime), persisted across screen navigations. */
+    val selectedPass: StateFlow<Pair<Int, Long>>
+
+    /** Set the currently selected pass. */
+    fun selectPass(catNum: Int, aosTime: Long)
+
+    /** Load satellite objects from DB based on the current selection. */
     suspend fun initRepository()
+
+    /** Recalculate passes with the given filter parameters. */
+    suspend fun calculatePasses(
+        time: Long,
+        hoursAhead: Int,
+        minElevation: Double,
+        aosStartMinute: Int,
+        aosEndMinute: Int,
+        invertAosTimeWindow: Boolean,
+        modes: List<String>
+    )
+
+    /** Get the current position of a single satellite. */
     suspend fun getPosition(sat: OrbitalObject, pos: GeoPos, time: Long): OrbitalPos
+
+    /** Get the ground track for a satellite over a time range. */
     suspend fun getTrack(sat: OrbitalObject, pos: GeoPos, start: Long, end: Long): List<OrbitalPos>
+
+    /** Get Doppler-shifted radio frequencies for a satellite at the given time. */
     suspend fun getRadios(sat: OrbitalObject, pos: GeoPos, radios: List<SatRadio>, time: Long): List<SatRadio>
-    suspend fun processPasses(passList: List<OrbitalPass>, time: Long): List<OrbitalPass>
-    suspend fun calculatePasses(time: Long, hoursAhead: Int, minElevation: Double, modes: List<String>)
+
+    /** Fetch radio transceivers for a satellite by its catalog number. */
+    suspend fun getRadiosWithId(id: Int): List<SatRadio>
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/ISensorsRepo.kt

@@ -21,7 +21,7 @@ import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import kotlinx.coroutines.flow.StateFlow
 
 interface ISensorsRepo {
-    val orientation: StateFlow<Pair<Float, Float>>
+    val sensorData: StateFlow<Pair<Float, Float>>
     fun getMagDeclination(geoPos: GeoPos, time: Long = System.currentTimeMillis()): Float
     fun enableSensor()
     fun disableSensor()

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/ISettingsRepo.kt

@@ -22,6 +22,8 @@ import com.rtbishop.look4sat.core.domain.model.DatabaseState
 import com.rtbishop.look4sat.core.domain.model.OtherSettings
 import com.rtbishop.look4sat.core.domain.model.PassesSettings
 import com.rtbishop.look4sat.core.domain.model.RCSettings
+import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
+import com.rtbishop.look4sat.core.domain.model.WavelogSettings
 import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import kotlinx.coroutines.flow.StateFlow
 
@@ -57,39 +59,53 @@ interface ISettingsRepo {
 
     //region # RC settings
     val rcSettings: StateFlow<RCSettings>
-    fun setBluetoothRotatorAddress(value: String)
-    fun setBluetoothRotatorFormat(value: String)
-    fun setBluetoothRotatorName(value: String)
-    fun setBluetoothRotatorState(value: Boolean)
-    fun setBluetoothFrequencyAddress(value: String)
-    fun setBluetoothFrequencyFormat(value: String)
-    fun setBluetoothFrequencyState(value: Boolean)
-    fun setRotatorAddress(value: String)
-    fun setRotatorPort(value: String)
-    fun setRotatorState(value: Boolean)
-    fun setRotatorFormat(value: String)
-    fun setFrequencyAddress(value: String)
-    fun setFrequencyPort(value: String)
-    fun setFrequencyState(value: Boolean)
-    fun setFrequencyFormat(value: String)
+    fun updateRCSettings(settings: RCSettings)
     //endregion
 
     //region # Other settings
     val otherSettings: StateFlow<OtherSettings>
-    fun setStateOfAutoUpdate(value: Boolean)
-    fun setStateOfSensors(value: Boolean)
-    fun setStateOfSweep(value: Boolean)
-    fun setStateOfUtc(value: Boolean)
-    fun setStateOfLightTheme(value: Boolean)
-    fun setWarningDismissed()
-    fun setWhatsNewDismissed()
+    fun updateOtherSettings(transform: (OtherSettings) -> OtherSettings)
+    fun setWarningDismissed() = updateOtherSettings { it.copy(shouldSeeWarning = false) }
+    fun setWhatsNewDismissed() = updateOtherSettings { it.copy(shouldSeeWhatsNew = false) }
     //endregion
 
     //region # Transceivers settings
     val dataSourcesSettings: StateFlow<DataSourcesSettings>
-    fun setUseCustomTle(value: Boolean)
-    fun setUseCustomTransceivers(value: Boolean)
-    fun setTleUrl(value: String)
-    fun setTransceiversUrl(value: String)
+    fun updateDataSourcesSettings(settings: DataSourcesSettings)
+    //endregion
+
+    //region # Data sources status
+    val dataSourcesStatus: StateFlow<Map<String, Int>>
+    fun updateDataSourcesStatus(status: Map<String, Int>)
+    //endregion
+
+    //region # Radio control settings
+    val radioControlSettings: StateFlow<RadioControlSettings>
+    fun updateRadioControlSettings(settings: RadioControlSettings)
+    //endregion
+
+    //region # Per-satellite calculator offset settings
+    fun getSatelliteOffset(catnum: Int): String
+    fun setSatelliteOffset(catnum: Int, offset: String)
+    //endregion
+
+    //region # AMSAT status report settings
+    fun getAmSatCallsign(): String
+    fun setAmSatCallsign(callsign: String)
+    //endregion
+
+    //region # Wavelog worked-grids settings
+    val wavelogSettings: StateFlow<WavelogSettings>
+    fun updateWavelogSettings(settings: WavelogSettings)
+    fun getWorkedGrids(): Set<String>
+    fun setWorkedGrids(grids: Set<String>)
+    /** Confirmed satellite QSOs grouped by worked 4-char gridsquare (map tap detail). */
+    fun getWorkedGridQsos(): Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>
+    fun setWorkedGridQsos(qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>)
+    //endregion
+
+    //region # LoTW confirmed-grids settings
+    val lotwSettings: StateFlow<com.rtbishop.look4sat.core.domain.model.LoTWSettings>
+    fun updateLoTWSettings(settings: com.rtbishop.look4sat.core.domain.model.LoTWSettings)
     //endregion
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IUpdateRepository.kt

@@ -0,0 +1,12 @@
+package com.rtbishop.look4sat.core.domain.repository
+
+import com.rtbishop.look4sat.core.domain.model.LatestRelease
+import java.io.File
+
+interface IUpdateRepository {
+    /** Fetch the latest release of the fork repo from GitHub; null on failure. */
+    suspend fun getLatestRelease(): LatestRelease?
+
+    /** Download the release APK from [url] into [dest]; true on success. */
+    suspend fun downloadApk(url: String, dest: File): Boolean
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/IWavelogRepository.kt

@@ -0,0 +1,28 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.repository
+
+/** Fetches worked gridsquares from a self-hosted Wavelog instance (API v2). */
+interface IWavelogRepository {
+
+    /**
+     * Fetch worked grids for the configured Wavelog URL/token.
+     * Returns the grid set, or null on any failure.
+     */
+    suspend fun fetchWorkedGrids(url: String, token: String): Set<String>?
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/repository/LoTWResult.kt

@@ -0,0 +1,45 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.repository
+
+/** Result of a LoTW report fetch, with the failure cause kept explicit. */
+sealed class LoTWResult {
+
+    /** Report downloaded and parsed successfully. */
+    data class Success(
+        val grids: Set<String>,
+        val qsos: Map<String, List<com.rtbishop.look4sat.core.domain.model.GridQso>>
+    ) : LoTWResult()
+
+    /** HTTP 200 but LoTW replied with its login-error page (bad callsign/password). */
+    data object BadCredentials : LoTWResult()
+
+    /**
+     * Report endpoint refused the request without a usable error page. LoTW
+     * limits downloads to one in progress per user id and flags accounts that
+     * pull the full report too often; the server answers those with a bare
+     * non-ADIF body (no <eoh>).
+     */
+    data object RateLimited : LoTWResult()
+
+    /** Connect/read timed out — typically a slow route to the ARRL servers. */
+    data object Timeout : LoTWResult()
+
+    /** Any other network-level failure (DNS, TLS, connection reset, HTTP 5xx). */
+    data class NetworkError(val detail: String) : LoTWResult()
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/source/IRemoteSource.kt

@@ -19,7 +19,18 @@ package com.rtbishop.look4sat.core.domain.source
 
 import java.io.InputStream
 
+/** Result of a network download: the HTTP status code and the response body stream. */
+data class NetworkResult(val code: Int, val stream: InputStream?) {
+    companion object {
+        /** Code used when a request fails before any HTTP response is received. */
+        const val CONNECTION_ERROR = -1
+    }
+}
+
 interface IRemoteSource {
     suspend fun getFileStream(uri: String): InputStream?
-    suspend fun getNetworkStream(url: String): InputStream?
+    suspend fun getNetworkStream(url: String): NetworkResult
+    suspend fun getAmSatCatalog(): String?
+    suspend fun getAmSatReports(hours: Int, limit: Int): String?
+    suspend fun submitAmSatReport(payloadJson: String): Pair<Int, String>?
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/source/Sources.kt

@@ -18,9 +18,11 @@
 package com.rtbishop.look4sat.core.domain.source
 
 object Sources {
-    const val RADIO_DATA_URL = "https://db.satnogs.org/api/transmitters/?format=json&status=active"
     val satelliteDataUrls = mapOf(
+        "LAPAN-A2" to "https://www.kaggle.com/api/v1/datasets/download/muazamnugroho/lapan-a2-satellite-two-line-element-tle-dataset/LAPAN-A2_TLE_latest.txt",
+        "R4UAB" to "https://r4uab.ru/satonline.txt",
         "All" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=active&FORMAT=csv",
+        "SatNOGS" to "https://db.satnogs.org/api/tle/?format=3le",
         "Amateur" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=amateur&FORMAT=csv",
         "Brightest" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=visual&FORMAT=csv",
         "Cubesat" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=cubesat&FORMAT=csv",
@@ -36,7 +38,7 @@ object Sources {
         "OneWeb" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=oneweb&FORMAT=csv",
         "Orbcomm" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=orbcomm&FORMAT=csv",
         "Resource" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=resource&FORMAT=csv",
-        "SatNOGS" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=satnogs&FORMAT=csv",
+        "CelesTrak SatNOGS" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=satnogs&FORMAT=csv",
         "Science" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=science&FORMAT=csv",
         "Spire" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=spire&FORMAT=csv",
         "Starlink" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=starlink&FORMAT=csv",
@@ -46,7 +48,11 @@ object Sources {
         "Amsat" to "https://amsat.org/tle/current/nasabare.txt",
         "Classified" to "https://www.mmccants.org/tles/classfd.zip",
         "McCants" to "https://www.mmccants.org/tles/inttles.zip",
-        "R4UAB" to "https://r4uab.ru/satonline.txt",
+        "ARISS" to "https://live.ariss.org/iss.txt",
         "Other" to "" // key for sats filter
     )
+    val transceiversDataUrls = mapOf(
+        "SatNOGS" to "https://db.satnogs.org/api/transmitters/?format=json&status=active",
+        "R4UAB" to "https://r4uab.ru/transmitters.json"
+    )
 }

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/sstv/SstvDecoder.kt

@@ -0,0 +1,816 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.sstv
+
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.channels.BufferOverflow
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.withContext
+import kotlin.math.PI
+import kotlin.math.abs
+import kotlin.math.round
+import kotlin.math.sqrt
+
+class SstvFrame(
+    val scopePixels: IntArray?,
+    val scopeWidth: Int,
+    val scopeHeight: Int,
+    val imagePixels: IntArray?,
+    val imageWidth: Int,
+    val imageHeight: Int,
+    val modeName: String,
+    val imageComplete: Boolean,
+    val inputRms: Float,
+    val appliedGain: Float,
+    val syncHitRate: Float,
+    val predictedLineBursts: Int,
+    val maxPredictedStreak: Int,
+    val timingErrorSamples: Int
+)
+
+/**
+ * Decoder quality metrics for diagnostics and logging. Useful for profiling decode
+ * performance on noisy recordings.
+ */
+data class SstvQualityMetrics(
+    val syncHitRate: Float,
+    val predictedLineBursts: Int,
+    val maxPredictedStreak: Int,
+    val timingErrorSamples: Int
+)
+
+enum class LineRecoveryStrategy {
+    Look4SatLimited,
+    Robot36Compatible
+}
+
+class SstvDiagnosticsHandle internal constructor(
+    val enabled: Boolean,
+    val metrics: StateFlow<SstvQualityMetrics?>
+)
+
+class SstvDecoder(
+    sampleRate: Int = 44100,
+    scopeWidth: Int = 320,
+    scopeHeight: Int = 256,
+    private val channelSelect: Int = 0,
+    targetRmsLevel: Float = 0.25f,
+    private val includeScopeData: Boolean = false,
+    private val enableRmsNormalization: Boolean = true,
+    preFilterCutoffHz: Double = 500.0,
+    enablePreFilter: Boolean = true,
+    private val enableDiagnosticsHandle: Boolean = false,
+    lineRecoveryStrategy: LineRecoveryStrategy = LineRecoveryStrategy.Look4SatLimited
+) {
+    private val scopeBuffer = PixelBuffer(scopeWidth, scopeHeight * 2)
+    private val imageBuffer = PixelBuffer(scopeWidth, scopeHeight)
+    private val decoder = DecoderEngine(scopeBuffer, imageBuffer, "Raw", sampleRate, lineRecoveryStrategy)
+    private val _frames = MutableSharedFlow<SstvFrame>(
+        replay = 1,
+        onBufferOverflow = BufferOverflow.DROP_OLDEST
+    )
+    private var lastInputRms = 0f
+    private var lastAppliedGain = 1f
+    private val _qualityMetrics = MutableStateFlow<SstvQualityMetrics?>(null)
+    private val preFilter = if (enablePreFilter) HighPassFilter(preFilterCutoffHz, sampleRate.toDouble()) else null
+    private val diagnosticsHandle = SstvDiagnosticsHandle(enableDiagnosticsHandle, _qualityMetrics)
+    val frames: SharedFlow<SstvFrame> = _frames
+    val supportedModes: List<String> = decoder.allModes.map { it.name }
+
+    suspend fun feedSamples(samples: FloatArray) = withContext(Dispatchers.Default) {
+        // Optional pre-filtering: remove DC offset and subsonic noise that can mask
+        // weak signals and corrupt the RMS normalization baseline.
+        preFilter?.apply(samples)
+
+        // Optional RMS normalization: bring input to a consistent level so the
+        // FM demodulator operates in a predictable region. However, this amplifies
+        // noise proportionally. Aggressive RMS targets (e.g., 0.25) can hurt weak
+        // signals by boosting noise floor. Safer defaults: 0.35-0.50 for noisy inputs.
+        // Disable entirely for direct line-level inputs (e.g., receiver discriminator).
+        val gain = if (enableRmsNormalization) normalise(samples) else GainInfo(0f, 1f)
+        lastInputRms = gain.inputRms
+        lastAppliedGain = gain.appliedGain
+        val hasNewLines = decoder.process(samples, channelSelect)
+        if (hasNewLines) emitFrame()
+    }
+
+    fun lockMode(modeName: String) = decoder.setMode(modeName)
+
+    fun clearPixels() {
+        imageBuffer.line = -1
+        imageBuffer.pixels.fill(0)
+        decoder.resetQuality()
+        if (enableDiagnosticsHandle) _qualityMetrics.value = null
+    }
+
+    fun getDiagnosticsHandle(): SstvDiagnosticsHandle? = diagnosticsHandle.takeIf { it.enabled }
+
+    /**
+     * Export quality metrics for logging/diagnostics. Useful for profiling decode
+     * performance on noisy recordings. Returns null before first frame is emitted.
+     */
+    @Suppress("unused")
+    fun getQualityMetrics(): SstvQualityMetrics? {
+        if (enableDiagnosticsHandle) return _qualityMetrics.value
+        val q = decoder.quality()
+        return SstvQualityMetrics(
+            syncHitRate = q.syncHitRate,
+            predictedLineBursts = q.predictedLineBursts,
+            maxPredictedStreak = q.maxPredictedStreak,
+            timingErrorSamples = q.timingErrorSamples
+        )
+    }
+
+    private fun emitFrame() {
+        val imageWidth = imageBuffer.width
+        val imageHeight = imageBuffer.height
+        val quality = decoder.quality()
+        if (enableDiagnosticsHandle) {
+            _qualityMetrics.value = SstvQualityMetrics(
+                syncHitRate = quality.syncHitRate,
+                predictedLineBursts = quality.predictedLineBursts,
+                maxPredictedStreak = quality.maxPredictedStreak,
+                timingErrorSamples = quality.timingErrorSamples
+            )
+        }
+        val imageComplete = imageBuffer.line >= imageHeight && imageBuffer.line > 0
+        // Copy only the active image region — imageBuffer.pixels is pre-allocated
+        // at the maximum possible size (PD-290: 800×616), so we must not copyOf()
+        // the entire array and send padding pixels to the observer.
+        val imagePixels = if (imageBuffer.line > 0) imageBuffer.pixels.copyOf(imageWidth * imageHeight) else null
+        val modeName = decoder.currentMode.name
+        val scopePixels = if (includeScopeData) scopeBuffer.pixels.copyOf() else null
+        val scopeWidth = if (includeScopeData) scopeBuffer.width else 0
+        val scopeHeight = if (includeScopeData) scopeBuffer.height else 0
+        _frames.tryEmit(
+            SstvFrame(
+                scopePixels = scopePixels,
+                scopeWidth = scopeWidth,
+                scopeHeight = scopeHeight,
+                imagePixels = imagePixels,
+                imageWidth = imageWidth,
+                imageHeight = imageHeight,
+                modeName = modeName,
+                imageComplete = imageComplete,
+                inputRms = lastInputRms,
+                appliedGain = lastAppliedGain,
+                syncHitRate = quality.syncHitRate,
+                predictedLineBursts = quality.predictedLineBursts,
+                maxPredictedStreak = quality.maxPredictedStreak,
+                timingErrorSamples = quality.timingErrorSamples
+            )
+        )
+    }
+
+    // Target RMS level for the normalizer. 0.25 leaves headroom while keeping the
+    // FM demodulator well above its noise floor regardless of input gain.
+    // TUNING GUIDE:
+    //   - 0.20-0.25: Aggressive, best for clean direct-coupled inputs, worst for mic noise
+    //   - 0.35-0.40: Moderate, good balance for typical phone/mic inputs (RECOMMENDED)
+    //   - 0.50-0.60: Conservative, best for noisy environments, reduces amplitude resolution
+    // Disable RMS normalization entirely if using a professional receiver discriminator output.
+    private val targetRms = targetRmsLevel.coerceIn(0.05f, 0.8f)
+
+    private class GainInfo(
+        val inputRms: Float,
+        val appliedGain: Float
+    )
+
+    // Bring the buffer to a fixed RMS so that microphone and direct-coupled inputs
+    // both decode reliably. The guard prevents amplifying pure silence into noise.
+    private fun normalise(buffer: FloatArray): GainInfo {
+        var sumSq = 0f
+        for (s in buffer) sumSq += s * s
+        val rms = sqrt(sumSq / buffer.size)
+        if (rms > 1e-6f) {
+            val gain = targetRms / rms
+            for (i in buffer.indices) buffer[i] *= gain
+            return GainInfo(rms, gain)
+        }
+        return GainInfo(rms, 1f)
+    }
+}
+
+/**
+ * Simple high-pass filter to remove DC offset and subsonic interference before RMS
+ * normalization. Improves noise floor estimation and prevents low-freq noise from
+ * corrupting the gain calculation.
+ *
+ * Design: First-order butterworth (pole at cutoff frequency). Fast, minimal latency,
+ * suitable for real-time preprocessing.
+ */
+internal class HighPassFilter(cutoffHz: Double, sampleRateHz: Double) {
+    private val alpha: Float
+    private var prevInput = 0f
+    private var prevOutput = 0f
+
+    init {
+        // First-order pole placement: alpha = wc / (wc + ws) where wc = 2*pi*fc, ws = 2*pi*fs
+        val omega = 2f * PI.toFloat() * (cutoffHz / sampleRateHz).toFloat()
+        alpha = omega / (omega + 1f)
+    }
+
+    fun apply(buffer: FloatArray) {
+        for (i in buffer.indices) {
+            val input = buffer[i]
+            prevOutput = alpha * (prevOutput + input - prevInput)
+            buffer[i] = prevOutput
+            prevInput = input
+        }
+    }
+}
+
+internal class DecoderQuality(
+    val syncHitRate: Float,
+    val predictedLineBursts: Int,
+    val maxPredictedStreak: Int,
+    val timingErrorSamples: Int
+)
+
+internal enum class SyncPulseWidth { FiveMs, NineMs, TwentyMs }
+
+internal class SyncPulseDetector(sampleRate: Int) {
+
+    companion object {
+        const val SYNC_FREQ = 1200.0
+        const val BLACK_FREQ = 1500.0
+        const val WHITE_FREQ = 2300.0
+    }
+
+    var detectedWidth: SyncPulseWidth = SyncPulseWidth.NineMs; private set
+    var pulseOffset: Int = 0; private set
+    var freqOffset: Float = 0f; private set
+
+    private val bandwidth = WHITE_FREQ - BLACK_FREQ
+    private val fm = FmDemodulator(bandwidth, sampleRate.toDouble())
+    private val min5ms: Int = round(0.0025 * sampleRate).toInt()
+    private val max5ms: Int = round(0.007 * sampleRate).toInt()
+    private val max9ms: Int = round(0.0145 * sampleRate).toInt()
+    private val max20ms: Int = round(0.025 * sampleRate).toInt()
+    private val filterDelay: Int
+    private val avgFilter: MovingAverage
+    private val delayLine: Delay
+    private val lowPass: ComplexFirFilter
+    private val oscillator: Phasor
+    private val syncFreqValue: Float
+    private val syncFreqTolerance: Float
+    private val trigger: SchmittTrigger
+    private var counter = 0
+    private var baseBand = Complex()
+
+    init {
+        val filterLen = round(0.0025 * sampleRate).toInt() or 1
+        filterDelay = (filterLen - 1) / 2
+        avgFilter = MovingAverage(filterLen)
+        delayLine = Delay(filterLen)
+        val loFreq = 1000.0
+        val hiFreq = 2800.0
+        val cutoff = (hiFreq - loFreq) / 2
+        val lpLen = round(0.002 * sampleRate).toInt() or 1
+        lowPass = ComplexFirFilter(lpLen)
+        for (i in 0 until lpLen)
+            lowPass.taps[i] = (WindowFunctions.kaiser(2.0, i, lpLen) * WindowFunctions.sinc(
+                cutoff,
+                sampleRate.toDouble(),
+                i,
+                lpLen
+            )).toFloat()
+        val center = (loFreq + hiFreq) / 2
+        oscillator = Phasor(-center, sampleRate.toDouble())
+        syncFreqValue = ((SYNC_FREQ - center) * 2 / bandwidth).toFloat()
+        syncFreqTolerance = (50 * 2 / bandwidth).toFloat()
+        val porchFreq = 1500.0
+        val hiThresh = (SYNC_FREQ + porchFreq) / 2
+        val loThresh = (SYNC_FREQ + hiThresh) / 2
+        trigger = SchmittTrigger(
+            ((loThresh - center) * 2 / bandwidth).toFloat(),
+            ((hiThresh - center) * 2 / bandwidth).toFloat()
+        )
+    }
+
+    fun process(buffer: FloatArray, channelSelect: Int): Boolean {
+        var detected = false
+        val channels = if (channelSelect > 0) 2 else 1
+        // NOTE: buffer[i] is overwritten in-place with the FM-demodulated frequency
+        // value for every mono sample (channelSelect == 0). DecoderEngine.process()
+        // reads back these values to populate scanLineBuffer. Callers must not reuse
+        // the buffer after this call.
+        for (i in 0 until buffer.size / channels) {
+            when (channelSelect) {
+                1 -> baseBand.set(buffer[2 * i])
+                2 -> baseBand.set(buffer[2 * i + 1])
+                3 -> baseBand.set(buffer[2 * i] + buffer[2 * i + 1])
+                4 -> baseBand.set(buffer[2 * i], buffer[2 * i + 1])
+                else -> baseBand.set(buffer[i])
+            }
+            baseBand = lowPass.filter(baseBand.mul(oscillator.rotate()))
+            val freq = fm.demodulate(baseBand)
+            val avg = avgFilter.avg(freq)
+            val delayed = delayLine.push(avg)
+            buffer[i] = freq
+            if (!trigger.process(avg)) {
+                ++counter
+            } else if (counter !in min5ms..max20ms || abs(delayed - syncFreqValue) > syncFreqTolerance) {
+                counter = 0
+            } else {
+                detectedWidth = when {
+                    counter < max5ms -> SyncPulseWidth.FiveMs
+                    counter < max9ms -> SyncPulseWidth.NineMs
+                    else -> SyncPulseWidth.TwentyMs
+                }
+                pulseOffset = i - filterDelay
+                freqOffset = delayed - syncFreqValue
+                detected = true
+                counter = 0
+            }
+        }
+        return detected
+    }
+}
+
+internal class DecoderEngine(
+    private val scopeBuffer: PixelBuffer,
+    private val imageBuffer: PixelBuffer,
+    rawName: String,
+    sampleRate: Int,
+    lineRecoveryStrategy: LineRecoveryStrategy
+) {
+    private val pixelBuffer = PixelBuffer(800, 2)
+    private val detector = SyncPulseDetector(sampleRate)
+    private val pulseFilter: MovingAverage
+    private val pulseFilterDelay: Int
+    private val scanLineBuffer: FloatArray
+    private val scratch: FloatArray
+    private val sync5ms = IntArray(5)
+    private val sync9ms = IntArray(5)
+    private val sync20ms = IntArray(5)
+    private val lines5ms = IntArray(4)
+    private val lines9ms = IntArray(4)
+    private val lines20ms = IntArray(4)
+    private val offsets5ms = FloatArray(5)
+    private val offsets9ms = FloatArray(5)
+    private val offsets20ms = FloatArray(5)
+    private val visFreqs = FloatArray(10)
+    private val scanLineMin: Int
+    private val syncTolerance: Int
+    private val lineTolerance: Int
+    private val leaderLen: Int
+    private val leaderTol: Int
+    private val transition: Int
+    private val visBitLen: Int
+    private val visLen: Int
+    private val rawMode: SstvMode
+    private val modes5ms: ArrayList<SstvMode>
+    private val modes9ms: ArrayList<SstvMode>
+    private val modes20ms: ArrayList<SstvMode>
+
+    var currentMode: SstvMode; private set
+    val allModes: List<SstvMode> get() = modes5ms + modes9ms + modes20ms
+
+    private var lockMode = false
+    private var sample = 0
+    private var leaderBreak = 0
+    private var lastSync = 0
+    private var curLineSamples: Int
+    private var lastOffset = 0f
+    private var syncChecks = 0
+    private var syncHits = 0
+    private var predictedLineBursts = 0
+    private var predictedStreak = 0
+    private var maxPredictedStreak = 0
+    private var timingErrorSamples = 0
+
+    // Look4Sat strategy limits synthetic lines to avoid visible vertical collapse.
+    // Robot36 strategy preserves legacy behavior by allowing unlimited synthesis.
+    private val maxConsecutivePredictedLines = when (lineRecoveryStrategy) {
+        LineRecoveryStrategy.Look4SatLimited -> 2
+        LineRecoveryStrategy.Robot36Compatible -> Int.MAX_VALUE
+    }
+
+    init {
+        imageBuffer.line = -1
+        // Pre-allocate for the largest possible mode (PD-290: 800×616 = 492 800 ints)
+        // so that handleHeader/processPulse can reuse the array with a fill(0) instead
+        // of allocating a fresh IntArray on every new image, reducing GC pressure.
+        imageBuffer.pixels = IntArray(800 * 616)
+        val pfLen = round(0.0025 * sampleRate).toInt() or 1
+        pulseFilterDelay = (pfLen - 1) / 2
+        pulseFilter = MovingAverage(pfLen)
+        scanLineBuffer = FloatArray(round(7.0 * sampleRate).toInt())
+        scratch = FloatArray(round(1.1 * sampleRate).toInt())
+        leaderLen = round(0.3 * sampleRate).toInt()
+        leaderTol = round(0.06 * sampleRate).toInt()
+        transition = round(0.0005 * sampleRate).toInt()
+        visBitLen = round(0.03 * sampleRate).toInt()
+        visLen = round(0.3 * sampleRate).toInt()
+        scanLineMin = round(0.05 * sampleRate).toInt()
+        syncTolerance = round(0.03 * sampleRate).toInt()
+        lineTolerance = round(0.001 * sampleRate).toInt()
+        rawMode = RawMode(rawName, sampleRate)
+        val robot36 = Robot36Mode(sampleRate)
+        currentMode = robot36
+        curLineSamples = robot36.scanLineSamples
+        modes5ms = arrayListOf(
+            RgbMode.wraaseSc2180(sampleRate),
+            RgbMode.martin("1", 44, 0.146432, sampleRate),
+            RgbMode.martin("2", 40, 0.073216, sampleRate)
+        )
+        modes9ms = arrayListOf(
+            robot36, Robot72Mode(sampleRate),
+            RgbMode.scottie("1", 60, 0.138240, sampleRate),
+            RgbMode.scottie("2", 56, 0.088064, sampleRate),
+            RgbMode.scottie("DX", 76, 0.3456, sampleRate)
+        )
+        modes20ms = arrayListOf(
+            PdMode("50", 93, 320, 256, 0.09152, sampleRate),
+            PdMode("90", 99, 320, 256, 0.17024, sampleRate),
+            PdMode("120", 95, 640, 496, 0.1216, sampleRate),
+            PdMode("160", 98, 512, 400, 0.195584, sampleRate),
+            PdMode("180", 96, 640, 496, 0.18304, sampleRate),
+            PdMode("240", 97, 640, 496, 0.24448, sampleRate),
+            PdMode("290", 94, 800, 616, 0.2288, sampleRate)
+        )
+    }
+
+    fun process(recordBuffer: FloatArray, channelSelect: Int): Boolean {
+        var newLines = false
+        val detected = detector.process(recordBuffer, channelSelect)
+        syncChecks++
+        if (detected) {
+            syncHits++
+            predictedStreak = 0
+        }
+        var syncIdx = sample + detector.pulseOffset
+        val channels = if (channelSelect > 0) 2 else 1
+        for (j in 0 until recordBuffer.size / channels) {
+            if (sample >= scanLineBuffer.size) {
+                shift(curLineSamples)
+                syncIdx -= curLineSamples
+                if (sample >= scanLineBuffer.size) sample = scanLineBuffer.size - 1
+            }
+            scanLineBuffer[sample++] = recordBuffer[j]
+        }
+        if (detected) {
+            when (detector.detectedWidth) {
+                SyncPulseWidth.FiveMs -> newLines = processPulse(modes5ms, offsets5ms, sync5ms, lines5ms, syncIdx)
+                SyncPulseWidth.NineMs -> {
+                    leaderBreak = syncIdx; newLines = processPulse(modes9ms, offsets9ms, sync9ms, lines9ms, syncIdx)
+                }
+
+                SyncPulseWidth.TwentyMs -> {
+                    leaderBreak = syncIdx; newLines = processPulse(modes20ms, offsets20ms, sync20ms, lines20ms, syncIdx)
+                }
+            }
+        } else if (handleHeader()) {
+            predictedStreak = 0
+            newLines = true
+        } else if (sample > lastSync + (curLineSamples * 5) / 4) {
+            newLines = decodePredictedLine()
+        }
+        return newLines
+    }
+
+    fun setMode(name: String) {
+        val mode = allModes.firstOrNull { it.name == name }
+        if (mode == currentMode) {
+            lockMode = true; return
+        }
+        if (mode != null) {
+            lockMode = true; imageBuffer.line = -1; currentMode = mode; curLineSamples = mode.scanLineSamples; return
+        }
+        lockMode = false
+    }
+
+    fun quality(): DecoderQuality {
+        val hitRate = if (syncChecks > 0) syncHits.toFloat() / syncChecks else 0f
+        return DecoderQuality(
+            syncHitRate = hitRate,
+            predictedLineBursts = predictedLineBursts,
+            maxPredictedStreak = maxPredictedStreak,
+            timingErrorSamples = timingErrorSamples
+        )
+    }
+
+    fun resetQuality() {
+        syncChecks = 0
+        syncHits = 0
+        predictedLineBursts = 0
+        predictedStreak = 0
+        maxPredictedStreak = 0
+        timingErrorSamples = 0
+    }
+
+    private fun mean(a: IntArray): Double = a.sumOf { it.toDouble() } / a.size
+    private fun stdDev(a: IntArray, m: Double): Double {
+        var s = 0.0; for (v in a) s += (v - m) * (v - m); return sqrt(s / a.size)
+    }
+
+    private fun meanF(a: FloatArray): Float {
+        var s = 0f; for (v in a) s += v; return s / a.size
+    }
+
+    private fun detectMode(modes: ArrayList<SstvMode>, samples: Int): SstvMode {
+        var best: SstvMode = rawMode
+        var bestD = Int.MAX_VALUE
+        for (m in modes) {
+            val d = abs(samples - m.scanLineSamples); if (d <= lineTolerance && d < bestD) {
+                bestD = d; best = m
+            }
+        }
+        return best
+    }
+
+    // scopeBuffer is twice the display height. Each decoded scan line is written
+    // to both the current rolling position (top half, wraps at height/2) and the
+    // same row offset in the bottom half. The UI displays a window that always
+    // spans the half-height boundary, giving a seamless non-wrapping scroll effect.
+    private fun copyUnscaled() {
+        val w = minOf(scopeBuffer.width, pixelBuffer.width)
+        for (row in 0 until pixelBuffer.height) {
+            val line = scopeBuffer.width * scopeBuffer.line
+            pixelBuffer.pixels.copyInto(scopeBuffer.pixels, line, row * pixelBuffer.width, row * pixelBuffer.width + w)
+            scopeBuffer.pixels.fill(0, line + w, line + scopeBuffer.width)
+
+            scopeBuffer.pixels.copyInto(
+                scopeBuffer.pixels,
+                scopeBuffer.width * (scopeBuffer.line + scopeBuffer.height / 2),
+                line,
+                line + scopeBuffer.width
+            )
+            scopeBuffer.line = (scopeBuffer.line + 1) % (scopeBuffer.height / 2)
+        }
+    }
+
+    private fun copyScaled(scale: Int) {
+        for (row in 0 until pixelBuffer.height) {
+            val line = scopeBuffer.width * scopeBuffer.line
+            for (col in 0 until pixelBuffer.width) for (i in 0 until scale) scopeBuffer.pixels[line + col * scale + i] =
+                pixelBuffer.pixels[pixelBuffer.width * row + col]
+            scopeBuffer.pixels.fill(0, line + pixelBuffer.width * scale, line + scopeBuffer.width)
+
+            scopeBuffer.pixels.copyInto(
+                scopeBuffer.pixels,
+                scopeBuffer.width * (scopeBuffer.line + scopeBuffer.height / 2),
+                line,
+                line + scopeBuffer.width
+            )
+            scopeBuffer.line = (scopeBuffer.line + 1) % (scopeBuffer.height / 2)
+            repeat(scale - 1) {
+
+                scopeBuffer.pixels.copyInto(
+                    scopeBuffer.pixels, scopeBuffer.width * scopeBuffer.line, line, line + scopeBuffer.width
+                )
+
+                scopeBuffer.pixels.copyInto(
+                    scopeBuffer.pixels,
+                    scopeBuffer.width * (scopeBuffer.line + scopeBuffer.height / 2),
+                    line,
+                    line + scopeBuffer.width
+                )
+                scopeBuffer.line = (scopeBuffer.line + 1) % (scopeBuffer.height / 2)
+            }
+        }
+    }
+
+    private fun copyLines(ok: Boolean) {
+        if (!ok) return
+        var finish = false
+        if (imageBuffer.line in 0 until imageBuffer.height && imageBuffer.width == pixelBuffer.width) {
+            val w = imageBuffer.width
+            for (row in 0 until pixelBuffer.height) {
+                if (imageBuffer.line >= imageBuffer.height) break
+                pixelBuffer.pixels.copyInto(imageBuffer.pixels, imageBuffer.line * w, row * w, row * w + w)
+                imageBuffer.line++
+            }
+            finish = imageBuffer.line == imageBuffer.height
+        }
+        val scale = scopeBuffer.width / pixelBuffer.width
+        if (scale <= 1) copyUnscaled() else copyScaled(scale)
+        if (finish) drawLines(0xff000000.toInt(), 10)
+    }
+
+    private fun decodePredictedLine(): Boolean {
+        // Avoid long streaks of synthetic lines; once we exceed the cap we wait for
+        // real sync to reduce visible vertical compression on weak/noisy signals.
+        if (predictedStreak >= maxConsecutivePredictedLines) return false
+        val expectedSync = lastSync + curLineSamples
+        timingErrorSamples = sample - expectedSync
+        val decoded = currentMode.decodeScanLine(
+            pixelBuffer,
+            scratch,
+            scanLineBuffer,
+            scopeBuffer.width,
+            lastSync,
+            curLineSamples,
+            lastOffset
+        )
+        copyLines(decoded)
+        lastSync = expectedSync
+        predictedLineBursts++
+        predictedStreak++
+        if (predictedStreak > maxPredictedStreak) maxPredictedStreak = predictedStreak
+        return decoded
+    }
+
+    private fun drawLines(color: Int, count: Int) {
+        repeat(count) {
+            scopeBuffer.pixels.fill(
+                color,
+                scopeBuffer.line * scopeBuffer.width,
+                (scopeBuffer.line + 1) * scopeBuffer.width
+            )
+            scopeBuffer.pixels.fill(
+                color,
+                (scopeBuffer.line + scopeBuffer.height / 2) * scopeBuffer.width,
+                (scopeBuffer.line + 1 + scopeBuffer.height / 2) * scopeBuffer.width
+            )
+            scopeBuffer.line = (scopeBuffer.line + 1) % (scopeBuffer.height / 2)
+        }
+    }
+
+    private fun adjust(pulses: IntArray, shift: Int) {
+        for (i in pulses.indices) pulses[i] -= shift
+    }
+
+    private fun shift(amount: Int) {
+        if ((amount <= 0) || (amount > sample)) return
+        sample -= amount; leaderBreak -= amount; lastSync -= amount
+        adjust(sync5ms, amount); adjust(sync9ms, amount); adjust(sync20ms, amount)
+        // Discard already-decoded samples by sliding the live region back to index 0.
+        // System.arraycopy handles the overlapping regions correctly and is a native
+        // memcpy on JVM, so this is fast despite moving the full remaining window.
+        scanLineBuffer.copyInto(scanLineBuffer, 0, amount, amount + sample)
+    }
+
+    private fun handleHeader(): Boolean {
+        if (leaderBreak < visBitLen + leaderTol || sample < leaderBreak + leaderLen + leaderTol + visLen + visBitLen) return false
+        val bp = leaderBreak; leaderBreak = 0
+        var preFreq = 0f
+        for (i in 0 until leaderTol) preFreq += scanLineBuffer[bp - visBitLen - leaderTol + i]
+        val toneFreq = 1900f
+        val center = 1900f
+        val tol = 50f
+        val halfBw = 400f
+        preFreq = preFreq * halfBw / leaderTol + center
+        if (abs(preFreq - toneFreq) > tol) return false
+        var ldrFreq = 0f
+        for (i in transition until leaderLen - leaderTol) ldrFreq += scanLineBuffer[bp + i]
+        val ldrOffset = ldrFreq / (leaderLen - transition - leaderTol)
+        ldrFreq = ldrOffset * halfBw + center
+        if (abs(ldrFreq - toneFreq) > tol) return false
+        val stopFreq = 1200f
+        val pulseThr = ((stopFreq + toneFreq) / 2 - center) / halfBw
+        var vBegin = bp + leaderLen - leaderTol
+        val vEnd = bp + leaderLen + leaderTol + visBitLen
+        repeat(pulseFilter.length) { pulseFilter.avg(scanLineBuffer[vBegin++] - ldrOffset) }
+        while (++vBegin < vEnd) if (pulseFilter.avg(scanLineBuffer[vBegin] - ldrOffset) < pulseThr) break
+        if (vBegin >= vEnd) return false
+        vBegin -= pulseFilterDelay
+        val visEnd = vBegin + visLen
+        visFreqs.fill(0f)
+        for (j in 0 until 10) for (i in transition until visBitLen - transition) visFreqs[j] += scanLineBuffer[vBegin + visBitLen * j + i] - ldrOffset
+        for (i in 0 until 10) visFreqs[i] = visFreqs[i] * halfBw / (visBitLen - 2 * transition) + center
+        if (abs(visFreqs[0] - stopFreq) > tol || abs(visFreqs[9] - stopFreq) > tol) return false
+        for (i in 1 until 9) if (abs(visFreqs[i] - 1100f) > tol && abs(visFreqs[i] - 1300f) > tol) return false
+        var vis = 0
+        for (i in 0 until 8) vis = vis or ((if (visFreqs[i + 1] < stopFreq) 1 else 0) shl i)
+        var chk = true; for (i in 0 until 8) chk = chk xor ((vis and (1 shl i)) != 0)
+        vis = vis and 127; if (!chk) return false
+        val syncThr = ((1200f + 1500f) / 2 - center) / halfBw
+        var sIdx = visEnd - visBitLen
+        val sMax = visEnd + visBitLen
+        repeat(pulseFilter.length) { pulseFilter.avg(scanLineBuffer[sIdx++] - ldrOffset) }
+        while (++sIdx < sMax) if (pulseFilter.avg(scanLineBuffer[sIdx] - ldrOffset) > syncThr) break
+        if (sIdx >= sMax) return false
+        sIdx -= pulseFilterDelay
+        val mode: SstvMode
+        val pulses: IntArray
+        val lines: IntArray
+        val f5 = modes5ms.firstOrNull { it.visCode == vis }
+        val f9 = modes9ms.firstOrNull { it.visCode == vis }
+        val f20 = modes20ms.firstOrNull { it.visCode == vis }
+        when {
+            f5 != null -> {
+                mode = f5; pulses = sync5ms; lines = lines5ms
+            }
+
+            f9 != null -> {
+                mode = f9; pulses = sync9ms; lines = lines9ms
+            }
+
+            f20 != null -> {
+                mode = f20; pulses = sync20ms; lines = lines20ms
+            }
+
+            else -> {
+                if (!lockMode) drawLines(0xffff0000.toInt(), 8); return false
+            }
+        }
+        if (lockMode && mode != currentMode) return false
+        mode.resetState()
+        imageBuffer.width = mode.width; imageBuffer.height = mode.height
+        imageBuffer.pixels.fill(0, 0, mode.width * mode.height); imageBuffer.line = 0
+        currentMode = mode
+        lastSync = sIdx + mode.firstSyncPulseIndex; curLineSamples = mode.scanLineSamples; lastOffset = ldrOffset
+        var oldest = lastSync - (pulses.size - 1) * curLineSamples
+        if (mode.firstSyncPulseIndex > 0) oldest -= curLineSamples
+        for (i in pulses.indices) pulses[i] = oldest + i * curLineSamples
+        lines.fill(curLineSamples)
+        shift(lastSync + mode.firstPixelSampleIndex)
+        drawLines(0xff00ff00.toInt(), 8); drawLines(0xff000000.toInt(), 10)
+        return true
+    }
+
+    private fun processPulse(
+        modes: ArrayList<SstvMode>,
+        freqOffs: FloatArray,
+        syncPulses: IntArray,
+        lineLen: IntArray,
+        latest: Int
+    ): Boolean {
+        predictedStreak = 0
+        for (i in 1 until syncPulses.size) syncPulses[i - 1] = syncPulses[i]
+        syncPulses[syncPulses.size - 1] = latest
+        for (i in 1 until lineLen.size) lineLen[i - 1] = lineLen[i]
+        lineLen[lineLen.size - 1] = syncPulses.last() - syncPulses[syncPulses.size - 2]
+        for (i in 1 until freqOffs.size) freqOffs[i - 1] = freqOffs[i]
+        freqOffs[freqOffs.size - 1] = detector.freqOffset
+        if (lineLen[0] == 0) return false
+        val m = mean(lineLen)
+        val lineSamples = round(m).toInt()
+        if (lineSamples < scanLineMin || lineSamples > scratch.size) return false
+        if (stdDev(lineLen, m) > lineTolerance) return false
+        var changed = false
+        if (lockMode || imageBuffer.line in 0 until imageBuffer.height) {
+            if (currentMode != rawMode && abs(lineSamples - currentMode.scanLineSamples) > lineTolerance) return false
+            // Try continuous decoding
+            if (lockMode && imageBuffer.line == -1 && currentMode != rawMode) {
+                currentMode.resetState()
+                imageBuffer.width = currentMode.width
+                imageBuffer.height = currentMode.height
+                imageBuffer.pixels.fill(0, 0, currentMode.width * currentMode.height)
+                imageBuffer.line = 0
+                drawLines(0xff000000.toInt(), 10); drawLines(0xffffff00.toInt(), 8); drawLines(0xff000000.toInt(), 10)
+            }
+        } else {
+            val prev = currentMode; currentMode = detectMode(modes, lineSamples)
+            changed =
+                currentMode != prev || abs(curLineSamples - lineSamples) > lineTolerance || abs(lastSync + lineSamples - syncPulses.last()) > syncTolerance
+        }
+        if (changed) {
+            drawLines(0xff000000.toInt(), 10); drawLines(0xff00ffff.toInt(), 8); drawLines(0xff000000.toInt(), 10)
+        }
+        val offset = meanF(freqOffs)
+        if (syncPulses[0] >= lineSamples && changed) {
+            val end = syncPulses[0]
+            val extra = end / lineSamples
+            val first = end - extra * lineSamples
+            var p = first; while (p < end) {
+                copyLines(
+                    currentMode.decodeScanLine(
+                        pixelBuffer,
+                        scratch,
+                        scanLineBuffer,
+                        scopeBuffer.width,
+                        p,
+                        lineSamples,
+                        offset
+                    )
+                ); p += lineSamples
+            }
+        }
+        val start = if (changed) 0 else lineLen.size - 1
+        for (i in start until lineLen.size) copyLines(
+            currentMode.decodeScanLine(
+                pixelBuffer,
+                scratch,
+                scanLineBuffer,
+                scopeBuffer.width,
+                syncPulses[i],
+                lineLen[i],
+                offset
+            )
+        )
+        lastSync = syncPulses.last(); curLineSamples = lineSamples; lastOffset = offset
+        shift(lastSync + currentMode.firstPixelSampleIndex)
+        return true
+    }
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/sstv/SstvDsp.kt

@@ -0,0 +1,240 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.sstv
+
+import kotlin.math.PI
+import kotlin.math.cos
+import kotlin.math.pow
+import kotlin.math.round
+import kotlin.math.sin
+import kotlin.math.sqrt
+
+internal class Complex(var real: Float = 0f, var imag: Float = 0f) {
+
+    fun set(real: Float, imag: Float): Complex {
+        this.real = real; this.imag = imag; return this
+    }
+
+    fun set(real: Float): Complex = set(real, 0f)
+
+    fun abs(): Float = sqrt(real * real + imag * imag)
+
+    fun mul(other: Complex): Complex {
+        val tmp = real * other.real - imag * other.imag
+        imag = real * other.imag + imag * other.real
+        real = tmp
+        return this
+    }
+
+    fun div(value: Float): Complex {
+        real /= value; imag /= value; return this
+    }
+}
+
+internal object WindowFunctions {
+
+    fun sinc(cutoff: Double, rate: Double, n: Int, nN: Int): Double {
+        val f = 2 * cutoff / rate
+        val x = n - (nN - 1) / 2.0
+        val fx = f * x
+        return if (fx == 0.0) f else f * sin(PI * fx) / (PI * fx)
+    }
+
+    fun kaiser(a: Double, n: Int, nN: Int): Double {
+        fun square(v: Double) = v * v
+        fun i0(x: Double): Double {
+            val terms = DoubleArray(35)
+            terms[0] = 1.0
+            var v = 1.0
+            for (m in 1 until 35) {
+                v *= x / (2 * m); terms[m] = square(v)
+            }
+            terms.sort()
+            var sum = 0.0; for (m in 34 downTo 0) sum += terms[m]
+            return sum
+        }
+        return i0(PI * a * sqrt(1 - square((2.0 * n) / (nN - 1) - 1))) / i0(PI * a)
+    }
+}
+
+// O(1) ring buffer — simpler and faster than a segment tree for the short window
+// lengths used here (≤512 samples). Float32 accumulated drift over such windows
+// is ~6e-5, negligible for audio-frequency processing.
+internal open class MovingSum(val length: Int) {
+    private val buf = FloatArray(length)
+    private var pos = 0
+    private var runningSum = 0f
+
+    fun add(input: Float) {
+        runningSum += input - buf[pos]
+        buf[pos] = input
+        if (++pos >= length) pos = 0
+    }
+
+    fun sum(): Float = runningSum
+    fun sum(input: Float): Float {
+        add(input); return sum()
+    }
+}
+
+internal class MovingAverage(length: Int) : MovingSum(length) {
+    fun avg(input: Float): Float = sum(input) / length
+}
+
+internal class Ema {
+    private var alpha: Float = 1f
+    private var prev: Float = 0f
+
+    fun process(input: Float): Float {
+        prev = prev * (1 - alpha) + alpha * input; return prev
+    }
+
+    fun setCutoff(freq: Double, rate: Double, order: Int = 1) {
+        alpha = computeAlpha(freq, rate, order)
+    }
+
+    fun reset() {
+        prev = 0f
+    }
+
+    companion object {
+
+        fun computeAlpha(freq: Double, rate: Double, order: Int = 1): Float {
+            val x = cos(2 * PI * (freq.coerceAtMost(rate * 0.499)) / rate)
+            val discriminant = (x * (x - 4) + 3).coerceAtLeast(0.0)
+            return (x - 1 + sqrt(discriminant)).coerceIn(0.0, 1.0).pow(1.0 / order).toFloat()
+        }
+
+        fun withCutoff(freq: Double, rate: Double, order: Int = 1): Ema {
+            return Ema().also { it.setCutoff(freq, rate, order) }
+        }
+    }
+}
+
+internal class Phasor(freq: Double, rate: Double) {
+    private val value = Complex(1f, 0f)
+    private val delta: Complex = run {
+        val omega = 2 * PI * freq / rate
+        Complex(cos(omega).toFloat(), sin(omega).toFloat())
+    }
+    private var count = 0
+
+    // Renormalize every 512 rotations to prevent magnitude drift accumulation,
+    // eliminating the per-sample sqrt without sacrificing demodulation accuracy.
+    fun rotate(): Complex {
+        value.mul(delta)
+        if (++count == 512) { value.div(value.abs()); count = 0 }
+        return value
+    }
+}
+
+internal class FmDemodulator(bandwidth: Double, sampleRate: Double) {
+    private val scale = (sampleRate / (bandwidth * PI)).toFloat()
+    private val pi = PI.toFloat()
+    private val twoPi = (2 * PI).toFloat()
+    private var prev = 0f
+
+    fun demodulate(input: Complex): Float {
+        // Use fast polynomial atan2 instead of the exact trigonometric call.
+        // Max error ~0.005 rad translates to <1 Hz frequency error at 44100 Hz,
+        // well within the 50 Hz sync tolerance.
+        val phase = fastAtan2(input.imag, input.real)
+        var delta = phase - prev; prev = phase
+        if (delta < -pi) delta += twoPi else if (delta > pi) delta -= twoPi
+        return scale * delta
+    }
+
+    // Rajan's polynomial approximation of atan2 — avoids a transcendental call
+    // in the per-sample hot path (~44 k calls/s at 44100 Hz sample rate).
+    private fun fastAtan2(y: Float, x: Float): Float {
+        val absY = kotlin.math.abs(y) + 1e-10f
+        val r: Float
+        val angle: Float
+        if (x >= 0f) {
+            r = (x - absY) / (x + absY)
+            angle = 0.1963f * r * r * r - 0.9817f * r + pi / 4f
+        } else {
+            r = (x + absY) / (absY - x)
+            angle = 0.1963f * r * r * r - 0.9817f * r + 3f * pi / 4f
+        }
+        return if (y < 0f) -angle else angle
+    }
+}
+
+internal class ComplexFirFilter(val length: Int) {
+    private val real = FloatArray(length)
+    private val imag = FloatArray(length)
+    private val sum = Complex()
+    private var pos = 0
+
+    val taps = FloatArray(length)
+
+    fun filter(input: Complex): Complex {
+        real[pos] = input.real; imag[pos] = input.imag
+        if (++pos >= length) pos = 0
+        sum.real = 0f; sum.imag = 0f
+        for (tap in taps) {
+            sum.real += tap * real[pos]; sum.imag += tap * imag[pos]; if (++pos >= length) pos = 0
+        }
+        return sum
+    }
+}
+
+internal class Delay(val length: Int) {
+    private val buf = FloatArray(length)
+    private var pos = 0
+
+    fun push(input: Float): Float {
+        val tmp = buf[pos]; buf[pos] = input; if (++pos >= length) pos = 0; return tmp
+    }
+}
+
+internal class SchmittTrigger(private val low: Float, private val high: Float) {
+    private var state = false
+
+    fun process(input: Float): Boolean {
+        if (state) {
+            if (input < low) state = false
+        } else {
+            if (input > high) state = true
+        }
+        return state
+    }
+}
+
+internal object ColorConverter {
+
+    private fun clamp(v: Int) = v.coerceIn(0, 255)
+    private fun toInt(level: Float) = clamp(round(255 * level).toInt())
+    private fun compress(level: Float) = toInt(sqrt(level.coerceIn(0f, 1f)))
+
+    private fun yuv2rgb(yY: Int, uU: Int, vV: Int): Int {
+        val y = yY - 16
+        val u = uU - 128
+        val v = vV - 128
+        val r = clamp((298 * y + 409 * v + 128) shr 8)
+        val g = clamp((298 * y - 100 * u - 208 * v + 128) shr 8)
+        val b = clamp((298 * y + 516 * u + 128) shr 8)
+        return 0xff000000.toInt() or (r shl 16) or (g shl 8) or b
+    }
+
+    fun gray(level: Float): Int = 0xff000000.toInt() or (0x00010101 * compress(level))
+    fun rgb(r: Float, g: Float, b: Float): Int = 0xff000000.toInt() or (toInt(r) shl 16) or (toInt(g) shl 8) or toInt(b)
+    fun yuv2rgb(yY: Float, uU: Float, vV: Float): Int = yuv2rgb(toInt(yY), toInt(uU), toInt(vV))
+    fun yuv2rgb(packed: Int): Int = yuv2rgb((packed shr 16) and 0xff, (packed shr 8) and 0xff, packed and 0xff)
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/sstv/SstvModes.kt

@@ -0,0 +1,434 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.sstv
+
+import kotlin.math.round
+
+internal class PixelBuffer(var width: Int, var height: Int) {
+    var pixels = IntArray(width * height)
+    var line = 0
+}
+
+internal sealed interface SstvMode {
+    val name: String
+    val visCode: Int
+    val width: Int
+    val height: Int
+    val firstPixelSampleIndex: Int
+    val firstSyncPulseIndex: Int
+    val scanLineSamples: Int
+
+    fun resetState() {}
+
+    fun decodeScanLine(
+        pixelBuffer: PixelBuffer,
+        scratch: FloatArray,
+        scanLine: FloatArray,
+        scopeWidth: Int,
+        syncPulseIndex: Int,
+        lineSamples: Int,
+        freqOffset: Float
+    ): Boolean
+}
+
+internal class RgbMode(
+    override val name: String,
+    override val visCode: Int,
+    private val hPixels: Int,
+    private val vPixels: Int,
+    override val firstSyncPulseIndex: Int,
+    override val scanLineSamples: Int,
+    override val firstPixelSampleIndex: Int,
+    private val redBegin: Int,
+    private val redLen: Int,
+    private val greenBegin: Int,
+    private val greenLen: Int,
+    private val blueBegin: Int,
+    private val blueLen: Int,
+    private val endSamples: Int,
+) : SstvMode {
+    override val width get() = hPixels
+    override val height get() = vPixels
+    private val ema = Ema.withCutoff(hPixels.toDouble(), (2 * greenLen).toDouble(), 2)
+
+    override fun decodeScanLine(
+        pixelBuffer: PixelBuffer,
+        scratch: FloatArray,
+        scanLine: FloatArray,
+        scopeWidth: Int,
+        syncPulseIndex: Int,
+        lineSamples: Int,
+        freqOffset: Float
+    ): Boolean {
+        val begin = firstPixelSampleIndex
+        if (syncPulseIndex + begin < 0 || syncPulseIndex + endSamples > scanLine.size) return false
+        ema.reset()
+        for (i in 0 until endSamples - begin) scratch[i] = ema.process(scanLine[syncPulseIndex + begin + i])
+        ema.reset()
+        for (i in endSamples - begin - 1 downTo 0) scratch[i] = freqToLevel(ema.process(scratch[i]), freqOffset)
+        for (i in 0 until hPixels) {
+            val r = redBegin + (i * redLen) / hPixels
+            val g = greenBegin + (i * greenLen) / hPixels
+            val b = blueBegin + (i * blueLen) / hPixels
+            pixelBuffer.pixels[i] = ColorConverter.rgb(scratch[r], scratch[g], scratch[b])
+        }
+        pixelBuffer.width = hPixels; pixelBuffer.height = 1
+        return true
+    }
+
+    companion object {
+        fun martin(variant: String, code: Int, channelSec: Double, sampleRate: Int): RgbMode {
+            val sync = 0.004862
+            val sep = 0.000572
+            val scanLine = sync + sep + 3 * (channelSec + sep)
+            val gEnd = sep + channelSec
+            val bBegin = gEnd + sep
+            val bEnd = bBegin + channelSec
+            val rBegin = bEnd + sep
+            val rEnd = rBegin + channelSec
+            return fromSeconds(
+                name = "Martin $variant",
+                code = code,
+                firstSyncSec = 0.0,
+                scanLineSec = scanLine,
+                beginSec = sep,
+                rBeginSec = rBegin,
+                rEndSec = rEnd,
+                gBeginSec = sep,
+                gEndSec = gEnd,
+                bBeginSec = bBegin,
+                bEndSec = bEnd,
+                endSec = rEnd,
+                sr = sampleRate
+            )
+        }
+
+        fun scottie(variant: String, code: Int, channelSec: Double, sampleRate: Int): RgbMode {
+            val sync = 0.009
+            val sep = 0.0015
+            val firstSync = sync + 2 * (sep + channelSec)
+            val scanLine = sync + 3 * (channelSec + sep)
+            val bEnd = -sync
+            val bBegin = bEnd - channelSec
+            val gEnd = bBegin - sep
+            val gBegin = gEnd - channelSec
+            val rEnd = sep + channelSec
+            return fromSeconds(
+                name = "Scottie $variant",
+                code = code,
+                firstSyncSec = firstSync,
+                scanLineSec = scanLine,
+                beginSec = gBegin,
+                rBeginSec = sep,
+                rEndSec = rEnd,
+                gBeginSec = gBegin,
+                gEndSec = gEnd,
+                bBeginSec = bBegin,
+                bEndSec = bEnd,
+                endSec = rEnd,
+                sr = sampleRate
+            )
+        }
+
+        fun wraaseSc2180(sampleRate: Int): RgbMode {
+            val sync = 0.0055225
+            val porch = 0.0005
+            val ch = 0.235
+            val scanLine = sync + porch + 3 * ch
+            val rEnd = porch + ch
+            val gEnd = rEnd + ch
+            val bEnd = gEnd + ch
+            return fromSeconds(
+                name = "Wraase SC2-180",
+                code = 55,
+                firstSyncSec = 0.0,
+                scanLineSec = scanLine,
+                beginSec = porch,
+                rBeginSec = porch,
+                rEndSec = rEnd,
+                gBeginSec = rEnd,
+                gEndSec = gEnd,
+                bBeginSec = gEnd,
+                bEndSec = bEnd,
+                endSec = bEnd,
+                sr = sampleRate
+            )
+        }
+
+        private fun fromSeconds(
+            name: String, code: Int, w: Int = 320, h: Int = 256,
+            firstSyncSec: Double, scanLineSec: Double, beginSec: Double,
+            rBeginSec: Double, rEndSec: Double, gBeginSec: Double, gEndSec: Double,
+            bBeginSec: Double, bEndSec: Double, endSec: Double, sr: Int
+        ): RgbMode {
+            val begin = round(beginSec * sr).toInt()
+            return RgbMode(
+                name = name, visCode = code, hPixels = w, vPixels = h,
+                firstSyncPulseIndex = round(firstSyncSec * sr).toInt(),
+                scanLineSamples = round(scanLineSec * sr).toInt(),
+                firstPixelSampleIndex = begin,
+                redBegin = round(rBeginSec * sr).toInt() - begin,
+                redLen = round((rEndSec - rBeginSec) * sr).toInt(),
+                greenBegin = round(gBeginSec * sr).toInt() - begin,
+                greenLen = round((gEndSec - gBeginSec) * sr).toInt(),
+                blueBegin = round(bBeginSec * sr).toInt() - begin,
+                blueLen = round((bEndSec - bBeginSec) * sr).toInt(),
+                endSamples = round(endSec * sr).toInt()
+            )
+        }
+    }
+}
+
+internal class Robot36Mode(sampleRate: Int) : SstvMode {
+    override val name = "Robot 36 Color"
+    override val visCode = 8
+    override val width = 320
+    override val height = 240
+    override val firstSyncPulseIndex = 0
+    override val scanLineSamples: Int
+    override val firstPixelSampleIndex: Int
+
+    private val lumSamples: Int
+    private val sepSamples: Int
+    private val chromSamples: Int
+    private val lumBegin: Int
+    private val sepBegin: Int
+    private val chromBegin: Int
+    private val end: Int
+    private val ema: Ema
+    private var lastEven = false
+
+    init {
+        val syncPorch = 0.003
+        val lum = 0.088
+        val sep = 0.0045
+        val porch = 0.0015
+        val chrom = 0.044
+        scanLineSamples = round((0.009 + syncPorch + lum + sep + porch + chrom) * sampleRate).toInt()
+        lumSamples = round(lum * sampleRate).toInt(); sepSamples = round(sep * sampleRate).toInt()
+        chromSamples = round(chrom * sampleRate).toInt()
+        lumBegin = round(syncPorch * sampleRate).toInt(); firstPixelSampleIndex = lumBegin
+        sepBegin = round((syncPorch + lum) * sampleRate).toInt()
+        chromBegin = round((syncPorch + lum + sep + porch) * sampleRate).toInt()
+        end = round((syncPorch + lum + sep + porch + chrom) * sampleRate).toInt()
+        ema = Ema.withCutoff(width.toDouble(), (2 * lumSamples).toDouble(), 2)
+    }
+
+    override fun resetState() {
+        lastEven = false
+    }
+
+    override fun decodeScanLine(
+        pixelBuffer: PixelBuffer,
+        scratch: FloatArray,
+        scanLine: FloatArray,
+        scopeWidth: Int,
+        syncPulseIndex: Int,
+        lineSamples: Int,
+        freqOffset: Float
+    ): Boolean {
+        if (syncPulseIndex + firstPixelSampleIndex < 0 || syncPulseIndex + end > scanLine.size) return false
+        var sep = 0f
+        for (i in 0 until sepSamples) sep += scanLine[syncPulseIndex + sepBegin + i]
+        sep = sep / sepSamples - freqOffset
+        var even = sep < 0
+        if (sep < -1.1f || (sep > -0.9f && sep < 0.9f) || sep > 1.1f) even = !lastEven
+        lastEven = even
+        ema.reset()
+        for (i in firstPixelSampleIndex until end) scratch[i] = ema.process(scanLine[syncPulseIndex + i])
+        ema.reset()
+        for (i in end - 1 downTo firstPixelSampleIndex) scratch[i] = freqToLevel(ema.process(scratch[i]), freqOffset)
+        for (i in 0 until width) {
+            val lPos = lumBegin + (i * lumSamples) / width
+            val cPos = chromBegin + (i * chromSamples) / width
+            if (even) {
+                // Even line: store Y in the red channel slot and Cr in the blue slot,
+                // using ColorConverter.rgb() as a convenient 3×byte packer (not RGB).
+                // The odd line will read these back and combine with its own Cb to
+                // produce the final YUV→RGB conversion for both rows.
+                pixelBuffer.pixels[i] = ColorConverter.rgb(scratch[lPos], 0f, scratch[cPos])
+            } else {
+                val evenYuv = pixelBuffer.pixels[i]
+                // Even pixel packing: 0xAARRGGBB → Y=RR, Cb=GG(unused), Cr=BB
+                // Odd pixel:  Y=lPos, Cb=cPos, Cr=(borrowed from even's BB slot)
+                // Merge: take Y+Cr from even row (bits 0x00ff00ff) and Cb from odd (0x0000ff00).
+                val oddYuv = ColorConverter.rgb(scratch[lPos], scratch[cPos], 0f)
+                pixelBuffer.pixels[i] = ColorConverter.yuv2rgb((evenYuv and 0x00ff00ff) or (oddYuv and 0x0000ff00))
+                pixelBuffer.pixels[i + width] =
+                    ColorConverter.yuv2rgb((oddYuv and 0x00ffff00) or (evenYuv and 0x000000ff))
+            }
+        }
+        pixelBuffer.width = width; pixelBuffer.height = 2
+        return !even
+    }
+}
+
+internal class Robot72Mode(sampleRate: Int) : SstvMode {
+    override val name = "Robot 72 Color"
+    override val visCode = 12
+    override val width = 320
+    override val height = 240
+    override val firstSyncPulseIndex = 0
+    override val scanLineSamples: Int
+    override val firstPixelSampleIndex: Int
+
+    private val lumSamples: Int
+    private val chromSamples: Int
+    private val yBegin: Int
+    private val vBegin: Int
+    private val uBegin: Int
+    private val end: Int
+    private val ema: Ema
+
+    init {
+        val syncPorch = 0.003
+        val lum = 0.138
+        val sep = 0.0045
+        val porch = 0.0015
+        val chrom = 0.069
+        scanLineSamples = round((0.009 + syncPorch + lum + 2 * (sep + porch + chrom)) * sampleRate).toInt()
+        lumSamples = round(lum * sampleRate).toInt(); chromSamples = round(chrom * sampleRate).toInt()
+        yBegin = round(syncPorch * sampleRate).toInt(); firstPixelSampleIndex = yBegin
+        vBegin = round((syncPorch + lum + sep + porch) * sampleRate).toInt()
+        uBegin = round((syncPorch + lum + sep + porch + chrom + sep + porch) * sampleRate).toInt()
+        end = round((syncPorch + lum + 2 * (sep + porch + chrom)) * sampleRate).toInt()
+        ema = Ema.withCutoff(width.toDouble(), (2 * lumSamples).toDouble(), 2)
+    }
+
+    override fun decodeScanLine(
+        pixelBuffer: PixelBuffer,
+        scratch: FloatArray,
+        scanLine: FloatArray,
+        scopeWidth: Int,
+        syncPulseIndex: Int,
+        lineSamples: Int,
+        freqOffset: Float
+    ): Boolean {
+        if (syncPulseIndex + firstPixelSampleIndex < 0 || syncPulseIndex + end > scanLine.size) return false
+        ema.reset()
+        for (i in firstPixelSampleIndex until end) scratch[i] = ema.process(scanLine[syncPulseIndex + i])
+        ema.reset()
+        for (i in end - 1 downTo firstPixelSampleIndex) scratch[i] = freqToLevel(ema.process(scratch[i]), freqOffset)
+        for (i in 0 until width) {
+            val yP = yBegin + (i * lumSamples) / width
+            val uP = uBegin + (i * chromSamples) / width
+            val vP = vBegin + (i * chromSamples) / width
+            pixelBuffer.pixels[i] = ColorConverter.yuv2rgb(scratch[yP], scratch[uP], scratch[vP])
+        }
+        pixelBuffer.width = width; pixelBuffer.height = 1
+        return true
+    }
+}
+
+internal class PdMode(
+    variant: String,
+    override val visCode: Int,
+    private val hPixels: Int,
+    private val vPixels: Int,
+    channelSec: Double,
+    sampleRate: Int
+) : SstvMode {
+    override val name = "PD $variant"
+    override val width get() = hPixels
+    override val height get() = vPixels
+    override val firstSyncPulseIndex = 0
+    override val scanLineSamples: Int
+    override val firstPixelSampleIndex: Int
+
+    private val chSamples: Int
+    private val yEvenBegin: Int
+    private val vAvgBegin: Int
+    private val uAvgBegin: Int
+    private val yOddBegin: Int
+    private val end: Int
+    private val ema: Ema
+
+    init {
+        val syncPorch = 0.00208
+        scanLineSamples = round((0.02 + syncPorch + 4 * channelSec) * sampleRate).toInt()
+        chSamples = round(channelSec * sampleRate).toInt()
+        yEvenBegin = round(syncPorch * sampleRate).toInt(); firstPixelSampleIndex = yEvenBegin
+        vAvgBegin = round((syncPorch + channelSec) * sampleRate).toInt()
+        uAvgBegin = round((syncPorch + 2 * channelSec) * sampleRate).toInt()
+        yOddBegin = round((syncPorch + 3 * channelSec) * sampleRate).toInt()
+        end = round((syncPorch + 4 * channelSec) * sampleRate).toInt()
+        ema = Ema.withCutoff(hPixels.toDouble(), (2 * chSamples).toDouble(), 2)
+    }
+
+    override fun decodeScanLine(
+        pixelBuffer: PixelBuffer,
+        scratch: FloatArray,
+        scanLine: FloatArray,
+        scopeWidth: Int,
+        syncPulseIndex: Int,
+        lineSamples: Int,
+        freqOffset: Float
+    ): Boolean {
+        if (syncPulseIndex + firstPixelSampleIndex < 0 || syncPulseIndex + end > scanLine.size) return false
+        ema.reset()
+        for (i in firstPixelSampleIndex until end) scratch[i] = ema.process(scanLine[syncPulseIndex + i])
+        ema.reset()
+        for (i in end - 1 downTo firstPixelSampleIndex) scratch[i] = freqToLevel(ema.process(scratch[i]), freqOffset)
+        for (i in 0 until hPixels) {
+            val pos = (i * chSamples) / hPixels
+            pixelBuffer.pixels[i] =
+                ColorConverter.yuv2rgb(scratch[pos + yEvenBegin], scratch[pos + uAvgBegin], scratch[pos + vAvgBegin])
+            pixelBuffer.pixels[i + hPixels] =
+                ColorConverter.yuv2rgb(scratch[pos + yOddBegin], scratch[pos + uAvgBegin], scratch[pos + vAvgBegin])
+        }
+        pixelBuffer.width = hPixels; pixelBuffer.height = 2
+        return true
+    }
+}
+
+internal class RawMode(override val name: String, sampleRate: Int) : SstvMode {
+    override val visCode = -1
+    override val width = -1
+    override val height = -1
+    override val firstPixelSampleIndex = 0
+    override val firstSyncPulseIndex = -1
+    override val scanLineSamples = -1
+
+    private val smallMax = round(0.125 * sampleRate).toInt()
+    private val medMax = round(0.175 * sampleRate).toInt()
+    private val ema = Ema()
+
+    override fun decodeScanLine(
+        pixelBuffer: PixelBuffer,
+        scratch: FloatArray,
+        scanLine: FloatArray,
+        scopeWidth: Int,
+        syncPulseIndex: Int,
+        lineSamples: Int,
+        freqOffset: Float
+    ): Boolean {
+        if (syncPulseIndex < 0 || syncPulseIndex + lineSamples > scanLine.size) return false
+        var px = scopeWidth
+        if (lineSamples < smallMax) px /= 2
+        if (lineSamples < medMax) px /= 2
+        ema.setCutoff(px.toDouble(), (2 * lineSamples).toDouble(), 2); ema.reset()
+        for (i in 0 until lineSamples) scratch[i] = ema.process(scanLine[syncPulseIndex + i])
+        ema.reset()
+        for (i in lineSamples - 1 downTo 0) scratch[i] = freqToLevel(ema.process(scratch[i]), freqOffset)
+        for (i in 0 until px) pixelBuffer.pixels[i] = ColorConverter.gray(scratch[(i * lineSamples) / px])
+        pixelBuffer.width = px; pixelBuffer.height = 1
+        return true
+    }
+}
+
+private fun freqToLevel(frequency: Float, offset: Float): Float = 0.5f * (frequency - offset + 1f)

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/usecase/IAudioCapture.kt

@@ -0,0 +1,34 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.usecase
+
+import kotlinx.coroutines.flow.Flow
+
+/**
+ * Platform abstraction for microphone audio capture.
+ * Produces a flow of mono Float PCM buffers at the configured sample rate.
+ */
+interface IAudioCapture {
+    val sampleRate: Int
+
+    /**
+     * Start capturing audio. Emits FloatArray buffers continuously until the flow is canceled.
+     * Caller is responsible for holding RECORD_AUDIO permission before calling this.
+     */
+    fun audioFlow(): Flow<FloatArray>
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/usecase/ISaveImage.kt

@@ -0,0 +1,26 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.usecase
+
+/**
+ * Saves a decoded SSTV image to the device gallery.
+ * @return true if the image was saved successfully
+ */
+interface ISaveImage {
+    suspend operator fun invoke(pixels: IntArray, width: Int, height: Int, modeName: String): Boolean
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/utility/DataParser.kt

@@ -21,134 +21,94 @@ import com.rtbishop.look4sat.core.domain.model.SatRadio
 import com.rtbishop.look4sat.core.domain.predict.OrbitalData
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.withContext
-import org.json.JSONArray
-import org.json.JSONObject
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonArray
+import kotlinx.serialization.json.decodeFromJsonElement
 import java.io.InputStream
 import kotlin.math.pow
 
 class DataParser(private val dispatcher: CoroutineDispatcher) {
 
+    private val json = Json {
+        ignoreUnknownKeys = true
+        coerceInputValues = true
+    }
+
     suspend fun parseCSVStream(stream: InputStream): List<OrbitalData> = withContext(dispatcher) {
-        val parsedItems = mutableListOf<OrbitalData>()
         stream.bufferedReader().useLines { lines ->
-            lines.forEachIndexed { index, line ->
-                if (index != 0) {
-                    val values = line.split(",")
-                    parseCSV(values)?.let { tle -> parsedItems.add(tle) }
-                }
-            }
+            lines.drop(1).mapNotNull { parseCSV(it.split(",")) }.toList()
         }
-        return@withContext parsedItems
     }
 
     suspend fun parseTLEStream(stream: InputStream): List<OrbitalData> = withContext(dispatcher) {
-        val tleStrings = mutableListOf(String(), String(), String())
-        val parsedItems = mutableListOf<OrbitalData>()
-        var lineIndex = 0
-        stream.bufferedReader().forEachLine { line ->
-            tleStrings[lineIndex] = line
-            if (lineIndex < 2) {
-                lineIndex++
-            } else {
-                val isLineOneValid = tleStrings[1].substring(0, 1) == "1"
-                val isLineTwoValid = tleStrings[2].substring(0, 1) == "2"
-                if (!isLineOneValid && !isLineTwoValid) return@forEachLine
-                parseTLE(tleStrings)?.let { tle -> parsedItems.add(tle) }
-                lineIndex = 0
-            }
-        }
-        return@withContext parsedItems
+        stream.bufferedReader().readLines()
+            .chunked(3)
+            .filter { it.size == 3 && it[1].startsWith("1") && it[2].startsWith("2") }
+            .mapNotNull { parseTLE(it) }
     }
 
     suspend fun parseJSONStream(stream: InputStream): List<SatRadio> = withContext(dispatcher) {
-        val parsedItems = mutableListOf<SatRadio>()
-        try {
-            val jsonArray = JSONArray(stream.bufferedReader().readText())
-            for (index in 0 until jsonArray.length()) {
-                val jsonObject = jsonArray.getJSONObject(index)
-                parseJSON(jsonObject)?.let { parsedItems.add(it) }
-            }
-            return@withContext parsedItems
-        } catch (_: Exception) {
-            return@withContext parsedItems
-        }
+        runCatching {
+            val root = json.parseToJsonElement(stream.bufferedReader().readText())
+            (root as? JsonArray)?.mapNotNull { element ->
+                runCatching { json.decodeFromJsonElement<SatRadio>(element) }
+                    .onFailure { println("JSON parsing exception: $it") }
+                    .getOrNull()
+            } ?: emptyList()
+        }.getOrDefault(emptyList())
     }
 
-    fun isLeapYear(year: Int): Boolean {
-        return ((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)
-    }
-
-    private fun parseCSV(values: List<String>): OrbitalData? = try {
+    private fun parseCSV(values: List<String>): OrbitalData? = runCatching {
         val name = values[0]
-        val year = values[2].substring(0, 4)
-        val month = values[2].substring(5, 7)
-        val dayOfMonth = values[2].substring(8, 10)
-        val dayInt = getDayOfYear(year.toInt(), month.toInt(), dayOfMonth.toInt())
-        val day = if (dayInt < 10) "00$dayInt" else if (dayInt < 100) "0$dayInt" else "$dayInt"
-        val hour = values[2].substring(11, 13).toInt() * 3600000 // ms in one hour
-        val min = values[2].substring(14, 16).toInt() * 60000 // ms in one minute
-        val sec = values[2].substring(17, 19).toInt() * 1000 // ms in one second
-        val ms = values[2].substring(20, 26).toInt() / 1000.0 // microseconds to ms
-        val frac = ((hour + min + sec + ms) / 86400000.0).toString()
-        val epoch = "${year.substring(2)}$day${frac.substring(1)}".toDouble()
-        val meanmo = values[3].toDouble()
-        val eccn = values[4].toDouble()
-        val incl = values[5].toDouble()
-        val raan = values[6].toDouble()
-        val argper = values[7].toDouble()
-        val meanan = values[8].toDouble()
-        val catnum = values[11].toInt()
-        val bstar = values[14].toDouble()
-        OrbitalData(name, epoch, meanmo, eccn, incl, raan, argper, meanan, catnum, bstar)
-    } catch (exception: Exception) {
-        println("CSV parsing exception: $exception")
-        null
-    }
+        val timestamp = values[2]
+        val year = timestamp.substring(0, 4)
+        val month = timestamp.substring(5, 7).toInt()
+        val dayOfMonth = timestamp.substring(8, 10).toInt()
+        val dayInt = getDayOfYear(year.toInt(), month, dayOfMonth)
+        val day = dayInt.toString().padStart(3, '0')
+        val hour = timestamp.substring(11, 13).toInt() * 3600000
+        val min = timestamp.substring(14, 16).toInt() * 60000
+        val sec = timestamp.substring(17, 19).toInt() * 1000
+        val ms = timestamp.substring(20, 26).toInt() / 1000.0
+        val frac = ((hour + min + sec + ms) / 86400000.0).toString().substring(1)
+        val epoch = "${year.substring(2)}$day$frac".toDouble()
+        OrbitalData(
+            name = name,
+            epoch = epoch,
+            meanmo = values[3].toDouble(),
+            eccn = values[4].toDouble(),
+            incl = values[5].toDouble(),
+            raan = values[6].toDouble(),
+            argper = values[7].toDouble(),
+            meanan = values[8].toDouble(),
+            catnum = values[11].toInt(),
+            bstar = values[14].toDouble(),
+            ndot = values[15].toDouble()
+        )
+    }.onFailure { println("CSV parsing exception: $it") }.getOrNull()
 
-    private fun parseTLE(tle: List<String>): OrbitalData? = try {
-        val name: String = tle[0].trim()
-        val epoch: Double = tle[1].substring(18, 32).toDouble()
-        val meanmo: Double = tle[2].substring(52, 63).toDouble()
-        val eccn: Double = tle[2].substring(26, 33).toDouble() / 10000000.0
-        val incl: Double = tle[2].substring(8, 16).toDouble()
-        val raan: Double = tle[2].substring(17, 25).toDouble()
-        val argper: Double = tle[2].substring(34, 42).toDouble()
-        val meanan: Double = tle[2].substring(43, 51).toDouble()
-        val catnum: Int = tle[1].substring(2, 7).trim().toInt()
-        val bstar: Double = 1.0e-5 * tle[1].substring(53, 59).toDouble() / 10.0.pow(tle[1].substring(60, 61).toDouble())
-        OrbitalData(name, epoch, meanmo, eccn, incl, raan, argper, meanan, catnum, bstar)
-    } catch (exception: Exception) {
-        println("TLE parsing exception: $exception")
-        null
-    }
+    private fun parseTLE(tle: List<String>): OrbitalData? = runCatching {
+        val line1 = tle[1]
+        val line2 = tle[2]
+        OrbitalData(
+            name = tle[0].trim(),
+            epoch = line1.substring(18, 32).toDouble(),
+            meanmo = line2.substring(52, 63).toDouble(),
+            eccn = line2.substring(26, 33).toDouble() / 1e7,
+            incl = line2.substring(8, 16).toDouble(),
+            raan = line2.substring(17, 25).toDouble(),
+            argper = line2.substring(34, 42).toDouble(),
+            meanan = line2.substring(43, 51).toDouble(),
+            catnum = line1.substring(2, 7).trim().toInt(),
+            bstar = 1e-5 * line1.substring(53, 59).toDouble() / 10.0.pow(line1.substring(60, 61).toDouble()),
+            ndot = line1.substring(33, 43).trim().toDouble()
+        )
+    }.onFailure { println("TLE parsing exception: $it") }.getOrNull()
 
-    private fun parseJSON(json: JSONObject): SatRadio? = try {
-        val uuid = json.getString("uuid")
-        val info = json.getString("description")
-        val alive = json.getBoolean("alive")
-        val dlinkLow = if (json.isNull("downlink_low")) null else json.getLong("downlink_low")
-        val dlinkHigh = if (json.isNull("downlink_high")) null else json.getLong("downlink_high")
-        val dlinkMode = if (json.isNull("mode")) null else json.getString("mode")
-        val ulinkLow = if (json.isNull("uplink_low")) null else json.getLong("uplink_low")
-        val ulinkHigh = if (json.isNull("uplink_high")) null else json.getLong("uplink_high")
-        val ulinkMode = if (json.isNull("uplink_mode")) null else json.getString("uplink_mode")
-        val inverted = json.getBoolean("invert")
-        val catnum = if (json.isNull("norad_cat_id")) null else json.getInt("norad_cat_id")
-        SatRadio(uuid, info, alive, dlinkLow, dlinkHigh, dlinkMode, ulinkLow, ulinkHigh, ulinkMode, inverted, catnum)
-    } catch (exception: Exception) {
-        println("JSON parsing exception: $exception")
-        null
-    }
+    fun isLeapYear(year: Int): Boolean = (year % 4 == 0 && year % 100 != 0) || year % 400 == 0
 
-    private fun getDayOfYear(year: Int, month: Int, dayOfMonth: Int): Int {
-        if (month == 1) return dayOfMonth
-        val daysArray = arrayOf(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31)
-        var dayOfYear = dayOfMonth
-        // If leap year increment Feb days
-        if (isLeapYear(year)) daysArray[1]++
-        for (i in 0 until month - 1) {
-            dayOfYear += daysArray[i]
-        }
-        return dayOfYear
+    fun getDayOfYear(year: Int, month: Int, dayOfMonth: Int): Int {
+        val daysInMonth = intArrayOf(31, if (isLeapYear(year)) 29 else 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31)
+        return daysInMonth.take(month - 1).sum() + dayOfMonth
     }
 }