diff --git a/core/domain/src/main/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApi.kt b/core/domain/src/main/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApi.kt
index f9491efe..5586fb08 100644
--- a/core/domain/src/main/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApi.kt
+++ b/core/domain/src/main/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApi.kt
@@ -225,7 +225,7 @@ object WaveLogApi {
     }
 
     /** v1 ADIF string (freq in MHz, length = UTF-8 byte count, sat_name normalized) */
-    private fun toAdif(qso: WavelogQso, gridsquare: String, satName: String): String {
+    internal fun toAdif(qso: WavelogQso, gridsquare: String, satName: String): String {
         fun field(name: String, value: String): String {
             val bytes = value.toByteArray(Charsets.UTF_8).size
             return "<$name:$bytes>$value"
@@ -243,7 +243,11 @@ object WaveLogApi {
             append(field("time_on", utcTimeCompact(qso.timeUtcMs)))
             append(field("rst_sent", "59"))
             append(field("rst_rcvd", "59"))
-            if (gridsquare.isNotBlank()) append(field("gridsquare", gridsquare.take(4)))
+            // Send the grid at full precision. Truncating to 4 characters threw
+            // away the 6-character locator the QRZ lookup provides, coarsening the
+            // stored position from ~4.6 km to ~100 km and making a QSO logged via
+            // v1 disagree with the same QSO logged via v2 (which sends it whole).
+            if (gridsquare.isNotBlank()) append(field("gridsquare", gridsquare))
             if (satName.isNotBlank()) {
                 append(field("sat_name", satName))
                 if (satMode.isNotBlank()) append(field("sat_mode", satMode))
diff --git a/core/domain/src/test/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApiPayloadTest.kt b/core/domain/src/test/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApiPayloadTest.kt
index 3c639788..aa68d19b 100644
--- a/core/domain/src/test/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApiPayloadTest.kt
+++ b/core/domain/src/test/java/com/rtbishop/look4sat/core/domain/wavelog/WaveLogApiPayloadTest.kt
@@ -39,6 +39,23 @@ class WaveLogApiPayloadTest {
         assertEquals(uplinkHz.toDouble(), adifFreq, 1.0)
     }
 
+    @Test
+    fun v1_adif_preservesSixCharacterGrid() {
+        val qso = WavelogQso(
+            id = "test",
+            timeUtcMs = 0L,
+            call = "BG7NTA",
+            mode = "FM",
+            freqTxHz = uplinkHz,
+            freqRxHz = downlinkHz,
+            satName = "SO-50"
+        )
+
+        val adif = WaveLogApi.toAdif(qso, "OM89ab", "SO-50")
+
+        assertTrue(adif.contains("<gridsquare:6>OM89ab"))
+    }
+
     /** Mirrors WaveLog Logbook_model::parse_frequency: int = Hz, "12.3M" suffix = MHz. */
     private fun parseLikeWaveLog(raw: String): Long {
         val s = raw.trim()