diff --git a/ArduCopter/Copter.cpp b/ArduCopter/Copter.cpp
index 7c9a0e91b3..bedc575a1f 100644
--- a/ArduCopter/Copter.cpp
+++ b/ArduCopter/Copter.cpp
@@ -659,7 +659,7 @@ void Copter::three_hz_loop()
     // check for deadreckoning failsafe
     failsafe_deadreckon_check();
 
-    // update ch6 in flight tuning
+    //update transmitter based in flight tuning
     tuning();
 
     // check if avoidance should be enabled based on alt
diff --git a/ArduCopter/mode_circle.cpp b/ArduCopter/mode_circle.cpp
index 8b2578d49b..5c1d243ed1 100644
--- a/ArduCopter/mode_circle.cpp
+++ b/ArduCopter/mode_circle.cpp
@@ -68,7 +68,7 @@ void ModeCircle::run()
         }
 
         // update the orbicular rate target based on pilot roll stick inputs
-        // skip if using CH6 tuning knob for circle rate
+        // skip if using transmitter based tuning knob for circle rate
         if (g.radio_tuning != TUNING_CIRCLE_RATE) {
             const float roll_stick = channel_roll->norm_input_dz();         // roll stick normalized -1 to 1