diff --git a/Makefile b/Makefile
index a8666bf..506f88d 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@
 # 1 = enable
 
 # ---- STOCK QUANSHENG FEATURES ----
-ENABLE_FMRADIO                	?= 1
+ENABLE_FMRADIO                	?= 0
 ENABLE_UART                   	?= 1
 ENABLE_AIRCOPY                	?= 0
 ENABLE_NOAA                   	?= 0
diff --git a/app/app.c b/app/app.c
index e41c3fc..9d87e5a 100644
--- a/app/app.c
+++ b/app/app.c
@@ -555,7 +555,7 @@ uint32_t APP_SetFreqByStepAndLimits(VFO_Info_t *pInfo, int8_t direction, uint32_
 #ifdef ENABLE_FEAT_F4HWN
     if (Frequency > upper)
 #else
-        if (Frequency >= upper)
+    if (Frequency >= upper)
 #endif
         Frequency = lower;
 
@@ -1135,10 +1135,9 @@ static void CheckKeys(void) {
             gPttDebounceCounter = 0;
     }
 #else
-    if (gPttIsPressed)
-    {
-        if (GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) || SerialConfigInProgress())
-        {   // PTT released or serial comms config in progress
+    if (gPttIsPressed) {
+        if (GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) ||
+            SerialConfigInProgress()) {   // PTT released or serial comms config in progress
             if (++gPttDebounceCounter >= 3 || SerialConfigInProgress())     // 30ms
             {   // stop transmitting
                 ProcessKey(KEY_PTT, false, false);
@@ -1146,21 +1145,17 @@ static void CheckKeys(void) {
                 if (gKeyReading1 != KEY_INVALID)
                     gPttWasReleased = true;
             }
-        }
-        else
+        } else
             gPttDebounceCounter = 0;
-    }
-    else if (!GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) && !SerialConfigInProgress())
-    {   // PTT pressed
+    } else if (!GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) && !SerialConfigInProgress()) {   // PTT pressed
         if (++gPttDebounceCounter >= 3)     // 30ms
         {   // start transmitting
-            boot_counter_10ms   = 0;
+            boot_counter_10ms = 0;
             gPttDebounceCounter = 0;
-            gPttIsPressed       = true;
+            gPttIsPressed = true;
             ProcessKey(KEY_PTT, true, false);
         }
-    }
-    else
+    } else
         gPttDebounceCounter = 0;
 #endif
 
@@ -1600,7 +1595,7 @@ void APP_TimeSlice500ms(void) {
 #endif
 
             if (disp == DISPLAY_INVALID
-                #ifdef ENABLE_NO_CODE_SCAN_TIMEOUT
+#ifdef ENABLE_NO_CODE_SCAN_TIMEOUT
                 && !SCANNER_IsScanning()
 #endif
                     ) {
@@ -1626,6 +1621,8 @@ void APP_TimeSlice500ms(void) {
 
     BATTERY_TimeSlice500ms();
     SCANNER_TimeSlice500ms();
+    MESSAGES_TimeSlice500ms();
+    FSKModem_TimeSlice500ms();
     UI_MAIN_TimeSlice500ms();
 
 #ifdef ENABLE_DTMF_CALLING
@@ -1856,7 +1853,7 @@ static void ProcessKey(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld) {
 #ifdef ENABLE_FEAT_F4HWN // For F + SIDE1 or F + SIDE2
     if (gWasFKeyPressed && (Key == KEY_PTT || Key == KEY_EXIT)) {
 #else
-        if (gWasFKeyPressed && (Key == KEY_PTT || Key == KEY_EXIT || Key == KEY_SIDE1 || Key == KEY_SIDE2)) {
+    if (gWasFKeyPressed && (Key == KEY_PTT || Key == KEY_EXIT || Key == KEY_SIDE1 || Key == KEY_SIDE2)) {
 #endif
         // cancel the F-key
         gWasFKeyPressed = false;
@@ -1896,7 +1893,7 @@ static void ProcessKey(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld) {
 
                     BK4819_ExitDTMF_TX(false);
 
-                        BK4819_SetScramble(gCurrentVfo->SCRAMBLING_TYPE);
+                    BK4819_SetScramble(gCurrentVfo->SCRAMBLING_TYPE);
 
                 }
             } else {
@@ -1930,15 +1927,15 @@ static void ProcessKey(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld) {
 #endif
     }
 #ifdef ENABLE_FEAT_F4HWN // For F + SIDE1 or F + SIDE2
-    else if (gWasFKeyPressed && (Key == KEY_SIDE1 || Key == KEY_SIDE2)) {
-        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
-    } else if (Key != KEY_SIDE1 && Key != KEY_SIDE2 && gScreenToDisplay != DISPLAY_INVALID) {
-        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
-    }
-#else
-        else if (Key != KEY_SIDE1 && Key != KEY_SIDE2 && gScreenToDisplay != DISPLAY_INVALID) {
+        else if (gWasFKeyPressed && (Key == KEY_SIDE1 || Key == KEY_SIDE2)) {
+            ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
+        } else if (Key != KEY_SIDE1 && Key != KEY_SIDE2 && gScreenToDisplay != DISPLAY_INVALID) {
             ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
         }
+#else
+    else if (Key != KEY_SIDE1 && Key != KEY_SIDE2 && gScreenToDisplay != DISPLAY_INVALID) {
+        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
+    }
 #endif
     else if (!SCANNER_IsScanning()
 #ifdef ENABLE_AIRCOPY
diff --git a/app/fskmodem.c b/app/fskmodem.c
index 5cf079c..499b199 100644
--- a/app/fskmodem.c
+++ b/app/fskmodem.c
@@ -17,6 +17,12 @@ uint8_t *dataPTR = dataPacket.data;
 
 SMSEnteringState gEnteringSMS = SMS_NOT_ENTERING;
 
+SMSResponseState gSMSResponseState = SMS_RESPONSE_IDLE;
+
+bool gGotACK = false;
+
+uint8_t SMSResponseCounter = 0;
+
 typedef enum {
     Receiving,
     Ready
@@ -24,6 +30,28 @@ typedef enum {
 
 RXState rxState = Ready;
 
+void FSKModem_TimeSlice500ms(void) {
+    if (SMSResponseCounter && SMSResponseCounter++ > 3) {
+        switch (gSMSResponseState) {
+            case SMS_RESPONSE_ACK:
+                inBoundPacket.flags |= 0x64;
+                inBoundPacket.dest = inBoundPacket.src;
+                inBoundPacket.src = gEeprom.FSKSRCAddress;
+                SYSTEM_DelayMs(200);
+                MSG_FSKSendData(&inBoundPacket);
+                break;
+            case SMS_RESPONSE_RETRANSMIT:
+                SYSTEM_DelayMs(200);
+                BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, true);
+                MSG_FSKSendData(packet);
+                BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, false);
+                break;
+            default:
+                break;
+        }
+    }
+}
+
 void MSG_ConfigureFSK(bool rx) {
     BK4819_WriteRegister(BK4819_REG_70, TONE2_ENABLE_BIT | (96U << 0));
 
@@ -130,13 +158,23 @@ void processReceivedPacket(DataPacket *packet) {
                                                                           : gEeprom.TX_VFO;
 
     if (packet->dest == gEeprom.FSKSRCAddress) {
-        AUDIO_PlayBeep(BEEP_500HZ_60MS_DOUBLE_BEEP);
-        BK4819_PlaySingleTone(1000, 250, 127, true);
-        strcpy(String, "SMS by ");
-        itoa(packet->src, numBuf);  // Convert number to string
-        strcat(String, numBuf);
-        MESSAGES_SAVE();
-        UI_DisplayPopup(String);
+        if ((packet->flags & 0x128)) {
+            if (packet->flags & 0x64) {
+                if (memcmp(inBoundPacket.data, dataPacket.data, DataPacketDataSize) == 0) {
+                    gGotACK = true;
+                }
+            } else {
+                AUDIO_PlayBeep(BEEP_500HZ_60MS_DOUBLE_BEEP);
+                BK4819_PlaySingleTone(1000, 250, 127, true);
+                strcpy(String, "SMS by ");
+                itoa(packet->src, numBuf);  // Convert number to string
+                strcat(String, numBuf);
+                MESSAGES_SAVE();
+                UI_DisplayPopup(String);
+                SMSResponseCounter = 1;
+                gSMSResponseState = SMS_RESPONSE_ACK;
+            }
+        }
 #ifdef ENABLE_FEAT_F4HWN
         if (isMainOnly()) {
             UI_PrintStringSmallNormal(String, 2, 0, 5);
@@ -150,9 +188,8 @@ void processReceivedPacket(DataPacket *packet) {
 
     } else if (VfoState[vfo] == VFO_STATE_NORMAL && !TX_freq_check(gCurrentVfo->freq_config_TX.Frequency)) {
         if (packet->ttl--) {
-            BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, true);
-            MSG_FSKSendData(packet);
-            BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, false);
+            SMSResponseCounter = 1;
+            gSMSResponseState = SMS_RESPONSE_RETRANSMIT;
         }
     }
 
@@ -166,7 +203,7 @@ bool MSG_FSKReceiveData() {
     }
 
     // Read the received data from FIFO
-    uint16_t *ptr = (uint16_t *) &inBoundPacket;
+    uint16_t *ptr = (uint16_t * ) & inBoundPacket;
     size_t wordCount = sizeof(inBoundPacket) / sizeof(uint16_t);
 
     for (size_t i = 0; i < wordCount; i++) {
@@ -314,6 +351,10 @@ void MSG_FSKSendData(DataPacket *dataPacketIn) {
         BK4819_ExitTxMute();
     }
 
+    if (!(dataPacketIn->flags & 0x64)) {
+        gGotACK = false;
+    }
+
 }
 
 void prepareDataPacket() {
@@ -348,7 +389,7 @@ void FSK_HANDLE_IRQ(unsigned short irq) {
 
     if (rx_fifo_almost_full && rxState == Receiving) {
         const uint16_t count = BK4819_ReadRegister(BK4819_REG_5E) & (7u << 0);  // Almost full threshold
-        uint16_t *ptr = (uint16_t *) &inBoundPacket;
+        uint16_t *ptr = (uint16_t * ) & inBoundPacket;
         size_t wordCount = sizeof(inBoundPacket) / sizeof(uint16_t);
 
         for (uint16_t i = 0; i < count && gFSKWriteIndex < wordCount; i++) {
diff --git a/app/fskmodem.h b/app/fskmodem.h
index ed7a1c8..1c6212d 100644
--- a/app/fskmodem.h
+++ b/app/fskmodem.h
@@ -111,10 +111,22 @@ typedef enum {
     SMS_ENTERING_MESSAGE
 } SMSEnteringState;
 
+typedef enum {
+    SMS_RESPONSE_IDLE,
+    SMS_RESPONSE_ACK,
+    SMS_RESPONSE_RETRANSMIT
+} SMSResponseState;
+
 extern SMSEnteringState gEnteringSMS;
+extern SMSResponseState gSMSResponseState;
 
 extern uint8_t *dataPTR;
 
+extern bool gGotACK;
+
+extern uint8_t SMSResponseCounter;
+
 void FSK_HANDLE_IRQ(unsigned short irq);
+void FSKModem_TimeSlice500ms(void);
 
 #endif //UV_K5_FIRMWARE_CUSTOM_FSKMODEM_H
diff --git a/app/messages.c b/app/messages.c
index 8e8b36a..19d85b5 100644
--- a/app/messages.c
+++ b/app/messages.c
@@ -26,6 +26,8 @@ uint8_t gActiveMessage = 0;
 
 StoredPacket loadedPacket;
 
+uint8_t gKeyTimeout = 0;
+
 void MESSAGES_SAVE() {
     uint8_t Data[8];
     EEPROM_ReadBuffer(SEQParameterEEPROM, Data, 8);
@@ -36,15 +38,15 @@ void MESSAGES_SAVE() {
     Data[1]++;
     EEPROM_WriteBuffer(SEQParameterEEPROM, Data);
     EEPROM_WriteBuffer(MESSAGES_START + (msgIndex * sizeof(StoredPacket)) + 0,
-                       (uint8_t *) &inBoundPacket + 4);   // metadata
+                       (uint8_t * ) & inBoundPacket + 4);   // metadata
     EEPROM_WriteBuffer(MESSAGES_START + (msgIndex * sizeof(StoredPacket)) + 8,
-                       (uint8_t *) &inBoundPacket + 12);   // message part 1
+                       (uint8_t * ) & inBoundPacket + 12);   // message part 1
     EEPROM_WriteBuffer(MESSAGES_START + (msgIndex * sizeof(StoredPacket)) + 16,
-                       (uint8_t *) &inBoundPacket + 20); // message part 2
+                       (uint8_t * ) & inBoundPacket + 20); // message part 2
     EEPROM_WriteBuffer(MESSAGES_START + (msgIndex * sizeof(StoredPacket)) + 24,
-                       (uint8_t *) &inBoundPacket + 28); // message part 3
+                       (uint8_t * ) & inBoundPacket + 28); // message part 3
     EEPROM_WriteBuffer(MESSAGES_START + (msgIndex * sizeof(StoredPacket)) + 32,
-                       (uint8_t *) &inBoundPacket + 36); // message part 4
+                       (uint8_t * ) & inBoundPacket + 36); // message part 4
 
 }
 
@@ -63,8 +65,15 @@ void updatePrevChar(KEY_Code_t Key) {
 
 }
 
+void MESSAGES_TimeSlice500ms(void) {
+    if (gKeyTimeout && gKeyTimeout++ > 2) {
+        gKeyTimeout = 0;
+        prevKey = KEY_EXIT;
+    }
+}
 
 void MESSAGES_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld) {
+    gKeyTimeout = 1;
     if (gEnteringSMS != SMS_NOT_ENTERING && !bKeyHeld && Key <= KEY_9) {
         if (!dataPTR || dataPTR < dataPacket.data) {
             dataPTR = dataPacket.data;
@@ -105,7 +114,7 @@ void MESSAGES_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld) {
                 if (bKeyPressed) {
                     memset(dataPacket.data, 0, DataPacketDataSize);
                     prepareDataPacket();
-                    dataPacket.flags = 126;
+                    dataPacket.flags = 0x80 | (gCurrentVfo->OUTPUT_POWER & 0x07);
                     gEnteringSMS = SMS_ENTERING_MESSAGE;
                 }
                 return;
@@ -176,10 +185,10 @@ void MESSAGES_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld) {
                 }
             } else {
                 if (bKeyPressed) {
-                    updatePrevChar(Key);
                     gRequestDisplayScreen = DISPLAY_MAIN;
                 }
             }
+            updatePrevChar(Key);
             break;
         default:
             if (!bKeyHeld && bKeyPressed)
diff --git a/app/messages.h b/app/messages.h
index d426dec..0f45f58 100644
--- a/app/messages.h
+++ b/app/messages.h
@@ -23,9 +23,12 @@ extern uint8_t gActiveMessage;
 
 extern StoredPacket loadedPacket;
 
+extern uint8_t gKeyTimeout;
+
 void MESSAGES_GET();
 void MESSAGES_DELETE();
 void MESSAGES_SAVE();
 void MESSAGES_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld);
+void MESSAGES_TimeSlice500ms(void);
 
 //#endif //BRNQUANFW_MESSAGES_H
diff --git a/ui/messages.c b/ui/messages.c
index d904133..d38976a 100644
--- a/ui/messages.c
+++ b/ui/messages.c
@@ -28,12 +28,13 @@ void UI_DisplayMessages(void) {
     UI_DisplayClear();
     if (gEnteringSMS != SMS_NOT_ENTERING) {
         if (gEnteringSMS == SMS_ENTERING_DEST) {
-            UI_PrintString("SMS dest", 0, 0, 1 /*, 8 */);
+            UI_PrintString("SMS dest", 0, 0, 0 /*, 8 */);
             u32_to_str(dataPacket.dest, String);
             UI_PrintStringSmallNormal(String, 0, 0, 2);
         } else if (gEnteringSMS == SMS_ENTERING_MESSAGE) {
-            UI_PrintString("SMS data", 0, 0, 1 /*, 8 */);
-            UI_PrintStringSmallNormal((const char *) dataPacket.data, 1, 0, 2);
+            UI_PrintString("SMS data", 0, 0, 0 /*, 8 */);
+            UI_PrintStringSmallNormal((const char *) dataPacket.data, 1, 0, 1);
+            memset(gFrameBuffer[1] + 2 + (7 * strlen((const char *) dataPacket.data)), gKeyTimeout == 0 ? 0xFF : 0x80, 6);
         }
     } else {