diff --git a/app/app.c b/app/app.c
index f0c6214..733d8bf 100644
--- a/app/app.c
+++ b/app/app.c
@@ -1182,9 +1182,12 @@ void APP_TimeSlice10ms(void)
 		if (gRxVfo->Modulation == MODULATION_AM && gSetting_AM_fix)
 			AM_fix_10ms(gEeprom.RX_VFO);
 #endif
-
+    char a[2]="SB";
+    UART_Send((uint8_t *)&a,2);
     if (UART_IsCommandAvailable())
     {
+        char a[2]="OK";
+        UART_Send((uint8_t *)&a,2);
         __disable_irq();
         UART_HandleCommand();
         __enable_irq();
diff --git a/app/uart.c b/app/uart.c
index adceba5..c6cbf9a 100644
--- a/app/uart.c
+++ b/app/uart.c
@@ -517,8 +517,7 @@ bool UART_IsCommandAvailable(void)
  void UART_HandleCommand(void)
 {
 //    volatile uint16_t CMD_ID=
-char a[2]="OK";
-     UART_Send((uint8_t *)&a,2);
+
      switch (UART_Command.Header.ID)
     {
         case 0x0514: