diff --git a/zephcore/boards/esp32/heltec_wifi_lora32_v4/board.conf b/zephcore/boards/esp32/heltec_wifi_lora32_v4/board.conf
index c8d68c4..ef71dbe 100644
--- a/zephcore/boards/esp32/heltec_wifi_lora32_v4/board.conf
+++ b/zephcore/boards/esp32/heltec_wifi_lora32_v4/board.conf
@@ -1,7 +1,7 @@
 # Heltec WiFi LoRa 32 V4 — ESP32-S3, 16 MB flash, 2 MB QSPI PSRAM
 #
 # Hardware:
-#   SX1262 + GC1109 external PA (10 dBm in → ~22 dBm out)
+#   SX1262 + GC1109 external PA (~27 dBm max radiated at TX=18)
 #   SSD1306 128x64 OLED on I2C0
 #   User button on GPIO0
 #
@@ -19,6 +19,6 @@ CONFIG_ESPTOOLPY_FLASHSIZE_16MB=y
 CONFIG_ZEPHCORE_SX126X_HELTEC_REG_PATCH=y
 
 # TX power — SX1262 input to GC1109 PA.
-# 10 dBm → ~22 dBm radiated output (GC1109 ~12 dB gain).
-# Driving >10 dBm into the PA compresses it; set as default but not capped.
-CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=10
+# Measured (MeshCore issue #1708): TX=18 → ~27 dBm radiated, practical efficiency peak.
+# TX=10 → ~20 dBm; TX=22 → ~27 dBm (PA saturated, same as TX=18, extra current only).
+CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=12
diff --git a/zephcore/boards/esp32/heltec_wifi_lora32_v43/board.conf b/zephcore/boards/esp32/heltec_wifi_lora32_v43/board.conf
index 0725bd4..aaf038b 100644
--- a/zephcore/boards/esp32/heltec_wifi_lora32_v43/board.conf
+++ b/zephcore/boards/esp32/heltec_wifi_lora32_v43/board.conf
@@ -20,6 +20,6 @@ CONFIG_ESPTOOLPY_FLASHSIZE_16MB=y
 CONFIG_ZEPHCORE_SX126X_HELTEC_REG_PATCH=y
 
 # TX power — SX1262 input to KCT8103L PA.
-# 10 dBm → ~22 dBm radiated output (KCT8103L similar gain to GC1109).
-# Driving >10 dBm into the PA compresses it; set as default but not capped.
-CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=10
+# Measured (MeshCore issue #1708, GC1109 data — KCT8103L similar): TX=18 → ~27 dBm
+# radiated, practical efficiency peak. TX=10 → ~20 dBm; TX=22 saturates same as TX=18.
+CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=12
diff --git a/zephcore/boards/esp32/station_g2/board.conf b/zephcore/boards/esp32/station_g2/board.conf
index 90bc2e7..fdccb57 100644
--- a/zephcore/boards/esp32/station_g2/board.conf
+++ b/zephcore/boards/esp32/station_g2/board.conf
@@ -16,7 +16,7 @@ CONFIG_BT_DIS_MODEL_NUMBER_STR="BQ Station G2"
 
 # TX power — Station G2 has ~20dB external PA.
 # Default 15 dBm → ~35 dBm output (P1dB point). Not capped — user can raise.
-CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=15
+CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=6
 
 # Flash size — 16MB (override Zephyr default)
 CONFIG_ESPTOOLPY_FLASHSIZE_16MB=y
diff --git a/zephcore/boards/nrf52840/ikoka_nano_30dbm/board.conf b/zephcore/boards/nrf52840/ikoka_nano_30dbm/board.conf
index 5cfffe9..b08a9a6 100644
--- a/zephcore/boards/nrf52840/ikoka_nano_30dbm/board.conf
+++ b/zephcore/boards/nrf52840/ikoka_nano_30dbm/board.conf
@@ -21,3 +21,6 @@ CONFIG_BT_DIS_MODEL_NUMBER_STR="Ikoka Nano 30dBm"
 # SoftDevice firmware ID (XIAO nRF52840 uses S140 v7.3.0)
 CONFIG_ZEPHCORE_SD_FWID=0x0123
 
+# TX power — SX1262 input to E22-900M30S PA (30 dBm rated output).
+CONFIG_ZEPHCORE_DEFAULT_TX_POWER_DBM=14
+