diff --git a/scripts/superkey/interface.py b/scripts/superkey/interface.py
index 37c662f..561f65b 100644
--- a/scripts/superkey/interface.py
+++ b/scripts/superkey/interface.py
@@ -176,6 +176,13 @@ def get_paddle_mode(self) -> PaddleMode:
         self.__send_packet(MessageID.REQUEST_GET_PADDLE_MODE)
         return PaddleMode(self.__check_reply('<B')[0])
 
+    def get_trainer_mode(self) -> bool:
+        """
+        Sends the `REQUEST_GET_TRAINER_MODE` command. Returns whether trainer mode is enabled or not.
+        """
+        self.__send_packet(MessageID.REQUEST_GET_TRAINER_MODE)
+        return self.__check_reply('<?')[0]
+
     def get_wpm(self) -> float:
         """
         Sends the `REQUEST_GET_WPM` command. Returns the current WPM setting.
@@ -260,6 +267,13 @@ def set_paddle_mode(self, mode: PaddleMode):
         self.__send_packet(MessageID.REQUEST_SET_PADDLE_MODE, struct.pack('<B', mode))
         self.__check_reply_empty()
 
+    def set_trainer_mode(self, enabled: bool):
+        """
+        Sends the `SET_TRAINER_MODE` command. Enables or disables trainer mode.
+        """
+        self.__send_packet(MessageID.REQUEST_SET_TRAINER_MODE, struct.pack('<?', enabled))
+        self.__check_reply_empty()
+
     def set_wpm(self, wpm: float):
         """
         Sends the `REQUEST_SET_WPM` command. Sets the keyer's WPM setting.
diff --git a/scripts/superkey/types.py b/scripts/superkey/types.py
index 0a53c2c..9658ff3 100644
--- a/scripts/superkey/types.py
+++ b/scripts/superkey/types.py
@@ -103,6 +103,7 @@
         'REQUEST_GET_IO_TYPE',
         'REQUEST_GET_LED_ENABLED',
         'REQUEST_GET_PADDLE_MODE',
+        'REQUEST_GET_TRAINER_MODE',
         'REQUEST_GET_WPM',
         'REQUEST_GET_WPM_SCALE',
         'REQUEST_PANIC',
@@ -115,6 +116,7 @@
         'REQUEST_SET_IO_TYPE',
         'REQUEST_SET_LED_ENABLED',
         'REQUEST_SET_PADDLE_MODE',
+        'REQUEST_SET_TRAINER_MODE',
         'REQUEST_SET_WPM',
         'REQUEST_SET_WPM_SCALE',
         'REQUEST_VERSION',
diff --git a/src/main/application/intf_port.c b/src/main/application/intf_port.c
index 28dea7a..22e8b90 100644
--- a/src/main/application/intf_port.c
+++ b/src/main/application/intf_port.c
@@ -163,6 +163,12 @@ static void process_message_request_get_led_enabled( intf_header_t const * heade
  */
 static void process_message_request_get_paddle_mode( intf_header_t const * header, void const * payload );
 
+/**
+ * @fn      process_message_request_get_trainer_mode( intf_header_t const *, void const * )
+ * @brief   Processes the specified interface message with the `INTF_MESSAGE_REQUEST_GET_TRAINER_MODE` message ID.
+ */
+static void process_message_request_get_trainer_mode( intf_header_t const * header, void const * payload );
+
 /**
  * @fn      process_message_request_get_wpm( intf_header_t const *, void const * )
  * @brief   Processes the specified interface message with the `INTF_MESSAGE_REQUEST_GET_WPM` message ID.
@@ -235,6 +241,12 @@ static void process_message_request_set_led_enabled( intf_header_t const * heade
  */
 static void process_message_request_set_paddle_mode( intf_header_t const * header, void const * payload );
 
+/**
+ * @fn      process_message_request_set_trainer_mode( intf_header_t const *, void const * )
+ * @brief   Processes the specified interface message with the `INTF_MESSAGE_REQUEST_SET_TRAINER_MODE` message ID.
+ */
+static void process_message_request_set_trainer_mode( intf_header_t const * header, void const * payload );
+
 /**
  * @fn      process_message_request_set_wpm( intf_header_t const *, void const * )
  * @brief   Processes the specified interface message with the `INTF_MESSAGE_REQUEST_sET_WPM` message ID.
@@ -410,6 +422,10 @@ static void process_message( intf_header_t const * header, void const * payload
         process_message_request_get_paddle_mode( header, payload );
         break;
 
+    case INTF_MESSAGE_REQUEST_GET_TRAINER_MODE:
+        process_message_request_get_trainer_mode( header, payload );
+        break;
+
     case INTF_MESSAGE_REQUEST_GET_WPM:
         process_message_request_get_wpm( header, payload );
         break;
@@ -458,6 +474,10 @@ static void process_message( intf_header_t const * header, void const * payload
         process_message_request_set_paddle_mode( header, payload );
         break;
 
+    case INTF_MESSAGE_REQUEST_SET_TRAINER_MODE:
+        process_message_request_set_trainer_mode( header, payload );
+        break;
+
     case INTF_MESSAGE_REQUEST_SET_WPM:
         process_message_request_set_wpm( header, payload );
         break;
@@ -609,6 +629,17 @@ static void process_message_request_get_led_enabled( intf_header_t const * heade
 }   /* process_message_request_get_paddle_mode() */
 
 
+static void process_message_request_get_trainer_mode( intf_header_t const * header, void const * payload )
+{
+    ( void )payload;
+    VALIDATE_PAYLOAD_SIZE_OR_BAIL( 0 );
+
+    bool enabled = keyer_get_trainer_mode_enabled();
+    send_packet( INTF_MESSAGE_REPLY_SUCCESS, & enabled, sizeof( enabled ) );
+
+}   /* process_message_request_get_trainer_mode() */
+
+
 static void process_message_request_get_wpm( intf_header_t const * header, void const * payload )
 {
     ( void )payload;
@@ -775,6 +806,17 @@ static void process_message_request_set_paddle_mode( intf_header_t const * heade
 }   /* process_message_request_set_paddle_mode() */
 
 
+static void process_message_request_set_trainer_mode( intf_header_t const * header, void const * payload )
+{
+    VALIDATE_PAYLOAD_SIZE_OR_BAIL( sizeof( bool ) );
+
+    bool enabled = *( ( bool const * )payload );
+    keyer_set_trainer_mode_enabled( enabled );
+    send_empty_packet( INTF_MESSAGE_REPLY_SUCCESS );
+
+}   /* process_message_request_set_trainer_mode() */
+
+
 static void process_message_request_set_wpm( intf_header_t const * header, void const * payload )
 {
     VALIDATE_PAYLOAD_SIZE_OR_BAIL( sizeof( wpm_t ) );
diff --git a/src/main/application/intf_types.h b/src/main/application/intf_types.h
index b808795..120dfaa 100644
--- a/src/main/application/intf_types.h
+++ b/src/main/application/intf_types.h
@@ -48,6 +48,7 @@ enum
     INTF_MESSAGE_REQUEST_GET_IO_TYPE,       /**< Gets I/O pin type.                     */
     INTF_MESSAGE_REQUEST_GET_LED_ENABLED,   /**< Gets enablement for LED.               */
     INTF_MESSAGE_REQUEST_GET_PADDLE_MODE,   /**< Gets the paddle mode.                  */
+    INTF_MESSAGE_REQUEST_GET_TRAINER_MODE,  /**< Gets enablement for trainer mode.      */
     INTF_MESSAGE_REQUEST_GET_WPM,           /**< Get WPM setting.                       */
     INTF_MESSAGE_REQUEST_GET_WPM_SCALE,     /**< Get element WPM scale.                 */
     INTF_MESSAGE_REQUEST_PANIC,             /**< Immediately stop the keyer.            */
@@ -60,6 +61,7 @@ enum
     INTF_MESSAGE_REQUEST_SET_IO_TYPE,       /**< Sets I/O pin type.                     */
     INTF_MESSAGE_REQUEST_SET_LED_ENABLED,   /**< Sets enablement for LED.               */
     INTF_MESSAGE_REQUEST_SET_PADDLE_MODE,   /**< Sets the paddle mode.                  */
+    INTF_MESSAGE_REQUEST_SET_TRAINER_MODE,  /**< Set enablement for trainer mode.       */
     INTF_MESSAGE_REQUEST_SET_WPM,           /**< Set WPM.                               */
     INTF_MESSAGE_REQUEST_SET_WPM_SCALE,     /**< Set WPM scale.                         */
     INTF_MESSAGE_REQUEST_VERSION,           /**< Get application version information.   */
diff --git a/src/main/application/keyer.c b/src/main/application/keyer.c
index 782803e..7bc6891 100644
--- a/src/main/application/keyer.c
+++ b/src/main/application/keyer.c
@@ -65,6 +65,7 @@ enum
 
 static bool s_keyed = false;                /**< Is the keyer hardware currently keyed? */
 static bool s_panicked = false;             /**< Was the keyer panic activated?         */
+static bool s_trainer_mode = false;         /**< Is trainer mode on?                    */
 
 static state_t s_state = STATE_OFF;         /**< Currently active keyer state.          */
 
@@ -655,11 +656,19 @@ keyer_paddle_mode_t keyer_get_paddle_mode( void )
 }   /* keyer_get_paddle_mode() */
 
 
+bool keyer_get_trainer_mode_enabled( void )
+{
+    return( s_trainer_mode );
+
+}   /* keyer_get_trainer_mode_enabled() */
+
+
 void keyer_init( void )
 {
     // Initialize local state
     s_keyed = false;
     s_panicked = false;
+    s_trainer_mode = false;
     s_state = STATE_OFF;
     s_el = WPM_ELEMENT_NONE;
     s_lockout_el = WPM_ELEMENT_NONE;
@@ -709,6 +718,15 @@ void keyer_set_paddle_mode( keyer_paddle_mode_t mode )
 }   /* keyer_set_paddle_mode() */
 
 
+void keyer_set_trainer_mode_enabled( bool enabled )
+{
+    s_trainer_mode = enabled;
+
+    update_hardware();
+
+}   /* keyer_set_trainer_mode_enabled() */
+
+
 void keyer_tick( tick_t tick )
 {
     // Update element tick counts if required
@@ -1053,7 +1071,7 @@ static void set_keyed( bool keyed )
 
 static void update_hardware( void )
 {
-    io_set_output_state_type( IO_TYPE_OUTPUT_KEYER, s_keyed ? IO_STATE_ON : IO_STATE_OFF );
+    io_set_output_state_type( IO_TYPE_OUTPUT_KEYER, s_keyed && ! s_trainer_mode ? IO_STATE_ON : IO_STATE_OFF );
     led_set_on( LED_KEY, s_keyed );
     buzzer_set_on( s_keyed );
 
diff --git a/src/main/application/keyer.h b/src/main/application/keyer.h
index 6167975..e21fbac 100644
--- a/src/main/application/keyer.h
+++ b/src/main/application/keyer.h
@@ -86,6 +86,13 @@ bool keyer_get_paddle_invert( void );
  */
 keyer_paddle_mode_t keyer_get_paddle_mode( void );
 
+/**
+ * @fn      keyer_get_trainer_mode_enabled( void )
+ * @brief   Returns `true` if trainer mode is enabled.
+ * @note    In trainer mode, the keyer output to any connected radios will not actually be activated.
+ */
+bool keyer_get_trainer_mode_enabled( void );
+
 /**
  * @fn      keyer_init( void )
  * @brief   Initializes the keyer module.
@@ -119,6 +126,13 @@ void keyer_set_paddle_invert( bool invert );
  */
 void keyer_set_paddle_mode( keyer_paddle_mode_t mode );
 
+/**
+ * @fn      keyer_set_trainer_mode_enabled( bool )
+ * @brief   Enables or disables trainer mode.
+ * @note    In trainer mode, the keyer output to any connected radios will not actually be activated.
+ */
+void keyer_set_trainer_mode_enabled( bool enabled );
+
 /**
  * @fn      keyer_tick( tick_t )
  * @brief   Performs periodic processing at the specified tick count.