diff --git a/IO.cpp b/IO.cpp
index 00521aa..344244e 100644
--- a/IO.cpp
+++ b/IO.cpp
@@ -1,8 +1,8 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016,2017,2018 by Andy Uribe CA6JAU
- *   Copyright (C) 2017 by Danilo DB4PLE 
- 
+ *   Copyright (C) 2017 by Danilo DB4PLE
+
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
  *   the Free Software Foundation; either version 2 of the License, or
@@ -105,9 +105,9 @@ void CIO::process()
   uint8_t bit;
   uint32_t scantime;
   uint8_t  control;
-  
+
   m_ledCount++;
-  
+
   if (m_started) {
     // Two seconds timeout
     if (m_watchdog >= 19200U) {
@@ -194,7 +194,7 @@ void CIO::process()
 
   if (m_rxBuffer.getData() >= 1U) {
     m_rxBuffer.get(bit, control);
-    
+
     switch (m_modemState_prev) {
       case STATE_DSTAR:
         dstarRX.databit(bit);
@@ -229,9 +229,9 @@ void CIO::process()
 }
 
 void CIO::start()
-{ 
+{
   m_TotalModes = 0U;
-  
+
   if(m_dstarEnable) {
     m_Modes[m_TotalModes] = STATE_DSTAR;
     m_TotalModes++;
@@ -252,7 +252,7 @@ void CIO::start()
     m_Modes[m_TotalModes] = STATE_NXDN;
     m_TotalModes++;
   }
-  
+
 #if defined(ENABLE_SCAN_MODE)
   if(m_TotalModes > 1U)
     m_scanEnable = true;
@@ -267,9 +267,9 @@ void CIO::start()
 
   if (m_started)
     return;
-    
+
   startInt();
-    
+
   m_started = true;
 }
 
@@ -284,7 +284,7 @@ void CIO::write(uint8_t* data, uint16_t length, const uint8_t* control)
     else
       m_txBuffer.put(data[i], control[i]);
   }
-  
+
   // Switch the transmitter on if needed
   if (!m_tx) {
     setTX();
@@ -338,6 +338,24 @@ uint8_t CIO::setFreq(uint32_t frequency_rx, uint32_t frequency_tx, uint8_t rf_po
     return 4U;
 #endif
 
+// Check if we have a single, dualband or duplex board
+#if defined (ZUMSPOT_ADF7021)
+ if (!(io.hasSingleADF7021())) {
+    // There are two ADF7021s on the board
+    if (io.isDualBand()) {
+      // Dual band
+      if ((frequency_tx <= VHF2_MAX) && (frequency_rx <= VHF2_MAX)) {
+        // Turn on VHF side
+        io.setBandVHF(true);
+      } else if ((frequency_tx >= UHF1_MIN) && (frequency_rx >= UHF1_MIN)) {
+        // Turn on UHF side
+        io.setBandVHF(false);
+      }
+    }
+  }
+
+#endif
+
   // Configure frequency
   m_frequency_rx = frequency_rx;
   m_frequency_tx = frequency_tx;
diff --git a/IO.h b/IO.h
index b455cff..bbc546b 100644
--- a/IO.h
+++ b/IO.h
@@ -1,8 +1,8 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016,2017,2018 by Andy Uribe CA6JAU
- *   Copyright (C) 2017 by Danilo DB4PLE 
- 
+ *   Copyright (C) 2017 by Danilo DB4PLE
+
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
  *   the Free Software Foundation; either version 2 of the License, or
@@ -124,6 +124,9 @@ public:
   uint32_t  getWatchdog(void);
   void      getIntCounter(uint16_t &int1, uint16_t &int2);
   void      selfTest(void);
+  void      setBandVHF(bool vhf_on);
+  bool      hasSingleADF7021(void);
+  bool      isDualBand(void);
 
   // RF interface API
   void      setTX(void);
@@ -164,7 +167,7 @@ private:
   uint16_t           m_RX_F_divider;
   uint8_t            m_TX_N_divider;
   uint16_t           m_TX_F_divider;
-  
+
   bool               m_started;
   CBitRB             m_rxBuffer;
   CBitRB             m_txBuffer;
diff --git a/IOSTM.cpp b/IOSTM.cpp
index 7fb5d84..f943d7b 100644
--- a/IOSTM.cpp
+++ b/IOSTM.cpp
@@ -115,6 +115,15 @@
 #define PIN_RXD              GPIO_Pin_4
 #define PORT_RXD             GPIOB
 
+#define PIN_SGL_DBL          GPIO_Pin_12
+#define PORT_SGL_DBL         GPIOA
+
+#define PIN_DL_DPX           GPIO_Pin_15
+#define PORT_DL_DPX          GPIOC
+
+#define PIN_SET_BAND         GPIO_Pin_15
+#define PORT_SET_BAND        GPIOA
+
 // TXD used in SPI Data mode of ADF7021
 // TXD is TxRxCLK of ADF7021, standard TX/RX data interface
 #define PIN_TXD              GPIO_Pin_3
@@ -326,6 +335,30 @@ void CIO::Init()
   GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);
 #endif
 
+#if defined(ZUMSPOT_ADF7021)
+  // Pin defines if the board has a single ADF7021 or double
+  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
+  GPIO_InitStruct.GPIO_Pin   = PIN_SGL_DBL;
+  GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_IPU;
+  GPIO_Init(PORT_SGL_DBL, &GPIO_InitStruct);
+
+  // Pin defines if the board is dual band or duplex
+  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
+  GPIO_InitStruct.GPIO_Pin   = PIN_DL_DPX;
+  GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_IPU;
+  GPIO_Init(PORT_DL_DPX, &GPIO_InitStruct);
+
+  // Pin will set UHF or VHF
+  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
+  GPIO_InitStruct.GPIO_Pin   = PIN_SET_BAND;
+  GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_Out_PP;
+  GPIO_Init(PORT_SET_BAND, &GPIO_InitStruct);
+  // TODO: Remove this line
+  // GPIO_WriteBit(PORT_SET_BAND, PIN_SET_BAND, Bit_RESET);
+
+#endif
+
+#if defined(STM32_USB_HOST)
   // Pin PA11,PA12 = LOW, USB Reset
   GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
   GPIO_InitStruct.GPIO_Pin   = GPIO_Pin_11 | GPIO_Pin_12;
@@ -334,6 +367,8 @@ void CIO::Init()
   GPIO_WriteBit(GPIOA, GPIO_Pin_11, Bit_RESET);
   GPIO_WriteBit(GPIOA, GPIO_Pin_12, Bit_RESET);
 
+#endif
+
 #if defined(LONG_USB_RESET)
   // 10 ms delay
   delay_us(10000U);
@@ -719,6 +754,17 @@ void CIO::COS_pin(bool on)
   GPIO_WriteBit(PORT_COS_LED, PIN_COS_LED, on ? Bit_SET : Bit_RESET);
 }
 
+void CIO::setBandVHF(bool vhf_on) {
+  GPIO_WriteBit(PORT_SET_BAND, PIN_SET_BAND, vhf_on ? Bit_SET : Bit_RESET);
+}
+
+bool CIO::hasSingleADF7021() {
+  return GPIO_ReadInputDataBit(PORT_SGL_DBL, PIN_SGL_DBL) == Bit_SET;
+}
+
+bool CIO::isDualBand() {
+  return GPIO_ReadInputDataBit(PORT_DL_DPX, PIN_DL_DPX) == Bit_SET;
+}
 
 /**
  * Function delay_us() from stm32duino project