diff --git a/SerialPort.cpp b/SerialPort.cpp
index 37d19ed..fd2678f 100644
--- a/SerialPort.cpp
+++ b/SerialPort.cpp
@@ -218,6 +218,7 @@ uint8_t CSerialPort::setConfig(const uint8_t* data, uint8_t length)
   bool rxInvert  = (data[0U] & 0x01U) == 0x01U;
   bool txInvert  = (data[0U] & 0x02U) == 0x02U;
   bool pttInvert = (data[0U] & 0x04U) == 0x04U;
+  bool ysfLoDev  = (data[0U] & 0x08U) == 0x08U;
   bool simplex   = (data[0U] & 0x80U) == 0x80U;
 
   bool dstarEnable = (data[1U] & 0x01U) == 0x01U;
@@ -275,6 +276,8 @@ uint8_t CSerialPort::setConfig(const uint8_t* data, uint8_t length)
   dmrDMORX.setColorCode(colorCode);
   dmrIdleRX.setColorCode(colorCode);
 
+  ysfTX.setLoDev(ysfLoDev);
+
   io.setParameters(rxInvert, txInvert, pttInvert, rxLevel, cwIdTXLevel, dstarTXLevel, dmrTXLevel, ysfTXLevel, p25TXLevel);
 
   io.start();
diff --git a/YSFTX.cpp b/YSFTX.cpp
index fcdcb87..5ed0a0b 100644
--- a/YSFTX.cpp
+++ b/YSFTX.cpp
@@ -37,10 +37,15 @@ static q15_t YSF_C4FSK_FILTER[] = {401, 104, -340, -731, -847, -553, 112, 909, 1
 const uint16_t YSF_C4FSK_FILTER_LEN = 42U;
 #endif
 
-const q15_t YSF_LEVELA[] = { 809,  809,  809,  809,  809};
-const q15_t YSF_LEVELB[] = { 269,  269,  269,  269,  269};
-const q15_t YSF_LEVELC[] = {-269, -269, -269, -269, -269};
-const q15_t YSF_LEVELD[] = {-809, -809, -809, -809, -809};
+const q15_t YSF_LEVELA_HI[] = { 809,  809,  809,  809,  809};
+const q15_t YSF_LEVELB_HI[] = { 269,  269,  269,  269,  269};
+const q15_t YSF_LEVELC_HI[] = {-269, -269, -269, -269, -269};
+const q15_t YSF_LEVELD_HI[] = {-809, -809, -809, -809, -809};
+
+const q15_t YSF_LEVELA_LO[] = { 405,  405,  405,  405,  405};
+const q15_t YSF_LEVELB_LO[] = { 135,  135,  135,  135,  135};
+const q15_t YSF_LEVELC_LO[] = {-135, -135, -135, -135, -135};
+const q15_t YSF_LEVELD_LO[] = {-405, -405, -405, -405, -405};
 
 const uint8_t YSF_START_SYNC = 0x77U;
 const uint8_t YSF_END_SYNC   = 0xFFU;
@@ -52,7 +57,8 @@ m_modState(),
 m_poBuffer(),
 m_poLen(0U),
 m_poPtr(0U),
-m_txDelay(240U)       // 200ms
+m_txDelay(240U),      // 200ms
+m_loDev(false)
 {
   ::memset(m_modState, 0x00U, 70U * sizeof(q15_t));
 
@@ -124,16 +130,16 @@ void CYSFTX::writeByte(uint8_t c)
   for (uint8_t i = 0U; i < 4U; i++, c <<= 2, p += YSF_RADIO_SYMBOL_LENGTH) {
     switch (c & MASK) {
       case 0xC0U:
-        ::memcpy(p, YSF_LEVELA, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
+        ::memcpy(p, m_loDev ? YSF_LEVELA_LO : YSF_LEVELA_HI, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
         break;
       case 0x80U:
-        ::memcpy(p, YSF_LEVELB, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
+        ::memcpy(p, m_loDev ? YSF_LEVELB_LO : YSF_LEVELB_HI, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
         break;
       case 0x00U:
-        ::memcpy(p, YSF_LEVELC, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
+        ::memcpy(p, m_loDev ? YSF_LEVELC_LO : YSF_LEVELC_HI, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
         break;
       default:
-        ::memcpy(p, YSF_LEVELD, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
+        ::memcpy(p, m_loDev ? YSF_LEVELD_LO : YSF_LEVELD_HI, YSF_RADIO_SYMBOL_LENGTH * sizeof(q15_t));
         break;
     }
   }
@@ -153,3 +159,8 @@ uint8_t CYSFTX::getSpace() const
   return m_buffer.getSpace() / YSF_FRAME_LENGTH_BYTES;
 }
 
+void CYSFTX::setLoDev(bool on)
+{
+  m_loDev = on;
+}
+
diff --git a/YSFTX.h b/YSFTX.h
index b51d5b7..c38cf96 100644
--- a/YSFTX.h
+++ b/YSFTX.h
@@ -35,6 +35,8 @@ public:
 
   uint8_t getSpace() const;
 
+  void setLoDev(bool on);
+
 private:
   CSerialRB            m_buffer;
   arm_fir_instance_q15 m_modFilter;
@@ -43,6 +45,7 @@ private:
   uint16_t             m_poLen;
   uint16_t             m_poPtr;
   uint16_t             m_txDelay;
+  bool                 m_loDev;
 
   void writeByte(uint8_t c);
 };