diff --git a/app/aircopy.c b/app/aircopy.c
index ccd08d7..9ec5633 100644
--- a/app/aircopy.c
+++ b/app/aircopy.c
@@ -44,10 +44,13 @@ uint16_t         g_aircopy_fsk_buffer[36];
 uint8_t          g_aircopy_send_count_down_10ms;
 unsigned int     g_aircopy_fsk_write_index;
 
-void AIRCOPY_SendMessage(void)
+void AIRCOPY_SendMessage(const uint8_t request_packet)
 {
 	unsigned int   i;
 	const uint16_t eeprom_addr = (uint16_t)g_aircopy_block_number * 64;
+
+	// will be used to ask the TX/ing radio to resend a missing/corrupted packet
+	(void)request_packet;
 	
 	// *********
 
@@ -72,11 +75,12 @@ void AIRCOPY_SendMessage(void)
 	for (i = 0; i < 34; i++)
 		g_aircopy_fsk_buffer[1 + i] ^= Obfuscation[i % ARRAY_SIZE(Obfuscation)];
 
+	// TX the packet
 	RADIO_SetTxParameters();
-
+	BK4819_SetupPowerAmplifier(0, g_current_vfo->pTX->frequency); // VERY low TX power
 	BK4819_SendFSKData(g_aircopy_fsk_buffer);
 	BK4819_SetupPowerAmplifier(0, 0);
-	BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1, false);
+	BK4819_set_GPIO_pin(BK4819_GPIO5_PIN1, false);
 
 	if (++g_aircopy_block_number >= g_aircopy_block_max)
 	{
@@ -250,11 +254,11 @@ static void AIRCOPY_Key_MENU(bool key_pressed, bool key_held)
 
 		g_aircopy_fsk_write_index = 0;
 		g_aircopy_block_number    = 0;
-		g_aircopy_fsk_buffer[0]   = AIRCOPY_MAGIC_START;
-		g_aircopy_fsk_buffer[1]   = 0;      // block number
-		g_aircopy_fsk_buffer[35]  = AIRCOPY_MAGIC_END;
 
-		AIRCOPY_SendMessage();
+		// send initial packet
+		//AIRCOPY_SendMessage(0xff);
+
+		g_aircopy_send_count_down_10ms = 30 / 10;   // 30ms
 	}
 }
 
diff --git a/app/aircopy.h b/app/aircopy.h
index 5a63da5..3ad2247 100644
--- a/app/aircopy.h
+++ b/app/aircopy.h
@@ -37,7 +37,7 @@ extern uint16_t         g_aircopy_fsk_buffer[36];
 extern uint8_t          g_aircopy_send_count_down_10ms;
 extern unsigned int     g_aircopy_fsk_write_index;
 
-void AIRCOPY_SendMessage(void);
+void AIRCOPY_SendMessage(const uint8_t request_packet);
 void AIRCOPY_StorePacket(void);
 void AIRCOPY_ProcessKeys(key_code_t key, bool key_pressed, bool key_held);
 
diff --git a/app/app.c b/app/app.c
index a1536b6..6bccef5 100644
--- a/app/app.c
+++ b/app/app.c
@@ -916,13 +916,13 @@ void APP_CheckRadioInterrupts(void)
 		if (interrupt_status_bits & BK4819_REG_02_SQUELCH_LOST)
 		{
 			g_squelch_lost = true;
-			BK4819_ToggleGpioOut(BK4819_GPIO0_PIN28_GREEN, true);
+			BK4819_set_GPIO_pin(BK4819_GPIO0_PIN28_GREEN, true);
 		}
 
 		if (interrupt_status_bits & BK4819_REG_02_SQUELCH_FOUND)
 		{
 			g_squelch_lost = false;
-			BK4819_ToggleGpioOut(BK4819_GPIO0_PIN28_GREEN, false);
+			BK4819_set_GPIO_pin(BK4819_GPIO0_PIN28_GREEN, false);
 		}
 
 		#ifdef ENABLE_AIRCOPY
@@ -1298,7 +1298,7 @@ void APP_Update(void)
 
 				BK4819_DisableVox();
 				BK4819_Sleep();
-				BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, false);
+				BK4819_set_GPIO_pin(BK4819_GPIO6_PIN2, false);
 
 				// Authentic device checked removed
 
@@ -1562,7 +1562,7 @@ void APP_TimeSlice10ms(void)
 			{
 				if (--g_aircopy_send_count_down_10ms == 0)
 				{
-					AIRCOPY_SendMessage();
+					AIRCOPY_SendMessage(0xff);
 					GUI_DisplayScreen();
 				}
 			}
@@ -1639,9 +1639,9 @@ void APP_TimeSlice10ms(void)
 
 						RADIO_EnableCxCSS();
 						BK4819_SetupPowerAmplifier(0, 0);
-						BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1, false);
+						BK4819_set_GPIO_pin(BK4819_GPIO5_PIN1, false);
 						BK4819_Enable_AfDac_DiscMode_TxDsp();
-						BK4819_ToggleGpioOut(BK4819_GPIO1_PIN29_RED, false);
+						BK4819_set_GPIO_pin(BK4819_GPIO1_PIN29_RED, false);
 
 						GUI_DisplayScreen();
 					}
@@ -1651,7 +1651,7 @@ void APP_TimeSlice10ms(void)
 
 						GUI_DisplayScreen();
 
-						BK4819_ToggleGpioOut(BK4819_GPIO1_PIN29_RED, true);
+						BK4819_set_GPIO_pin(BK4819_GPIO1_PIN29_RED, true);
 						RADIO_SetTxParameters();
 						BK4819_TransmitTone(true, 500);
 						SYSTEM_DelayMs(2);
diff --git a/app/spectrum.c b/app/spectrum.c
index 8a2c9cc..c4823d1 100644
--- a/app/spectrum.c
+++ b/app/spectrum.c
@@ -364,7 +364,7 @@ static void ToggleRX(bool on) {
     ToggleTX(false);
   }
 
-  BK4819_ToggleGpioOut(BK4819_GPIO0_PIN28_GREEN, on);
+  BK4819_set_GPIO_pin(BK4819_GPIO0_PIN28_GREEN, on);
   BK4819_RX_TurnOn();
 
   ToggleAudio(on);
@@ -399,7 +399,7 @@ static void ToggleTX(bool on) {
     ToggleRX(false);
   }
 
-  BK4819_ToggleGpioOut(BK4819_GPIO1_PIN29_RED, on);
+  BK4819_set_GPIO_pin(BK4819_GPIO1_PIN29_RED, on);
 
   if (on) {
     ToggleAudio(false);
@@ -434,8 +434,8 @@ static void ToggleTX(bool on) {
 
     SetF(fMeasure);
   }
-  BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, !on);
-  BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1, on);
+  BK4819_set_GPIO_pin(BK4819_GPIO6_PIN2, !on);
+  BK4819_set_GPIO_pin(BK4819_GPIO5_PIN1, on);
 }
 
 // Scan info
diff --git a/driver/bk4819.c b/driver/bk4819.c
index d8a491a..7137295 100644
--- a/driver/bk4819.c
+++ b/driver/bk4819.c
@@ -347,7 +347,7 @@ void BK4819_SetAGC(uint8_t Value)
 	}
 }
 
-void BK4819_ToggleGpioOut(BK4819_GPIO_PIN_t Pin, bool bSet)
+void BK4819_set_GPIO_pin(BK4819_GPIO_PIN_t Pin, bool bSet)
 {
 	if (bSet)
 		gBK4819_GpioOutState |=  (0x40u >> Pin);
@@ -703,7 +703,7 @@ void BK4819_SetupPowerAmplifier(const uint8_t bias, const uint32_t frequency)
 	//                                  280MHz       gain 1 = 1  gain 2 = 0  gain 1 = 4  gain 2 = 2
 	const uint8_t gain   = (frequency < 28000000) ? (1u << 3) | (0u << 0) : (4u << 3) | (2u << 0);
 	const uint8_t enable = 1;
-	BK4819_WriteRegister(BK4819_REG_36, (bias << 8) | (enable << 7) | (gain << 0));
+	BK4819_WriteRegister(BK4819_REG_36, ((uint16_t)bias << 8) | ((uint16_t)enable << 7) | ((uint16_t)gain << 0));
 }
 
 void BK4819_SetFrequency(uint32_t Frequency)
@@ -845,19 +845,19 @@ void BK4819_PickRXFilterPathBasedOnFrequency(uint32_t Frequency)
 {
 	if (Frequency < 28000000)
 	{
-		BK4819_ToggleGpioOut(BK4819_GPIO2_PIN30, true);
-		BK4819_ToggleGpioOut(BK4819_GPIO3_PIN31, false);
+		BK4819_set_GPIO_pin(BK4819_GPIO2_PIN30, true);
+		BK4819_set_GPIO_pin(BK4819_GPIO3_PIN31, false);
 	}
 	else
 	if (Frequency == 0xFFFFFFFF)
 	{
-		BK4819_ToggleGpioOut(BK4819_GPIO2_PIN30, false);
-		BK4819_ToggleGpioOut(BK4819_GPIO3_PIN31, false);
+		BK4819_set_GPIO_pin(BK4819_GPIO2_PIN30, false);
+		BK4819_set_GPIO_pin(BK4819_GPIO3_PIN31, false);
 	}
 	else
 	{
-		BK4819_ToggleGpioOut(BK4819_GPIO2_PIN30, false);
-		BK4819_ToggleGpioOut(BK4819_GPIO3_PIN31, true);
+		BK4819_set_GPIO_pin(BK4819_GPIO2_PIN30, false);
+		BK4819_set_GPIO_pin(BK4819_GPIO3_PIN31, true);
 	}
 }
 
@@ -1203,7 +1203,7 @@ void BK4819_Conditional_RX_TurnOn_and_GPIO6_Enable(void)
 {
 	if (g_rx_idle_mode)
 	{
-		BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, true);
+		BK4819_set_GPIO_pin(BK4819_GPIO6_PIN2, true);
 		BK4819_RX_TurnOn();
 	}
 }
diff --git a/driver/bk4819.h b/driver/bk4819.h
index 5eed69b..d0bcada 100644
--- a/driver/bk4819.h
+++ b/driver/bk4819.h
@@ -69,7 +69,7 @@ void     BK4819_WriteU16(uint16_t Data);
 
 void     BK4819_SetAGC(uint8_t Value);
 
-void     BK4819_ToggleGpioOut(BK4819_GPIO_PIN_t Pin, bool bSet);
+void     BK4819_set_GPIO_pin(BK4819_GPIO_PIN_t Pin, bool bSet);
 
 void     BK4819_SetCDCSSCodeWord(uint32_t CodeWord);
 void     BK4819_SetCTCSSFrequency(uint32_t BaudRate);
diff --git a/firmware.bin b/firmware.bin
index add066d..98b775f 100644
Binary files a/firmware.bin and b/firmware.bin differ
diff --git a/firmware.packed.bin b/firmware.packed.bin
index 3f89cf8..7ae3208 100644
Binary files a/firmware.packed.bin and b/firmware.packed.bin differ
diff --git a/functions.c b/functions.c
index 45bc802..e2cf6fb 100644
--- a/functions.c
+++ b/functions.c
@@ -167,7 +167,7 @@ void FUNCTION_Select(function_type_t Function)
 			BK4819_DisableVox();			
 			BK4819_Sleep();
 
-			BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, false);
+			BK4819_set_GPIO_pin(BK4819_GPIO6_PIN2, false);
 
 			g_update_status = true;
 
@@ -229,7 +229,7 @@ void FUNCTION_Select(function_type_t Function)
 			RADIO_SetTxParameters();
 
 			// turn the RED LED on
-			BK4819_ToggleGpioOut(BK4819_GPIO1_PIN29_RED, true);
+			BK4819_set_GPIO_pin(BK4819_GPIO1_PIN29_RED, true);
 
 			DTMF_Reply();
 
diff --git a/radio.c b/radio.c
index 217fcb7..cbd85fc 100644
--- a/radio.c
+++ b/radio.c
@@ -589,7 +589,7 @@ void RADIO_SetupRegisters(bool bSwitchToFunction0)
 
 	g_enable_speaker = false;
 
-	BK4819_ToggleGpioOut(BK4819_GPIO0_PIN28_GREEN, false);
+	BK4819_set_GPIO_pin(BK4819_GPIO0_PIN28_GREEN, false);
 
 	#pragma GCC diagnostic push
 	#pragma GCC diagnostic ignored "-Wimplicit-fallthrough="
@@ -611,11 +611,11 @@ void RADIO_SetupRegisters(bool bSwitchToFunction0)
 
 	#pragma GCC diagnostic pop
 
-	BK4819_ToggleGpioOut(BK4819_GPIO1_PIN29_RED, false);
+	BK4819_set_GPIO_pin(BK4819_GPIO1_PIN29_RED, false);
 
 	BK4819_SetupPowerAmplifier(0, 0);
 
-	BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1, false);
+	BK4819_set_GPIO_pin(BK4819_GPIO5_PIN1, false);
 
 	while (1)
 	{
@@ -649,7 +649,7 @@ void RADIO_SetupRegisters(bool bSwitchToFunction0)
 	BK4819_PickRXFilterPathBasedOnFrequency(Frequency);
 
 	// what does this in do ?
-	BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, true);
+	BK4819_set_GPIO_pin(BK4819_GPIO6_PIN2, true);
 
 	// AF RX Gain and DAC
 	BK4819_WriteRegister(BK4819_REG_48, 0xB3A8);  // 1011 00 111010 1000
@@ -843,7 +843,7 @@ void RADIO_SetTxParameters(void)
 
 	g_enable_speaker = false;
 
-	BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2, false);
+	BK4819_set_GPIO_pin(BK4819_GPIO6_PIN2, false);
 
 	#pragma GCC diagnostic push
 	#pragma GCC diagnostic ignored "-Wimplicit-fallthrough="
@@ -876,7 +876,7 @@ void RADIO_SetTxParameters(void)
 
 	BK4819_PickRXFilterPathBasedOnFrequency(g_current_vfo->pTX->frequency);
 
-	BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1, true);
+	BK4819_set_GPIO_pin(BK4819_GPIO5_PIN1, true);
 
 	SYSTEM_DelayMs(5);