diff --git a/src/extras/RFControl.h b/src/extras/RFControl.h
index 91c86d4..ea8f731 100644
--- a/src/extras/RFControl.h
+++ b/src/extras/RFControl.h
@@ -13,15 +13,19 @@
 using std::vector;
 
 class RFControl {
+  friend class Pixel;
+  
   private:
     rmt_config_t *config=NULL;
     vector<uint32_t> data;
     boolean lowWord=true;
     boolean refClock;
     static uint8_t nChannels;
-                               
+
+    RFControl(uint8_t pin, boolean refClock, boolean installDriver);        // private constructor (only used by Pixel class)
+
   public:    
-    RFControl(uint8_t pin, boolean refClock=true, boolean installDriver=true);        // creates transmitter on pin, using 1-MHz Ref Tick clock
+    RFControl(uint8_t pin, boolean refClock=true):RFControl(pin,refClock,true){};     // public constructor to create transmitter on pin, using 1-MHz Ref Tick clock or 80-MHz APB clock
     
     void start(uint32_t *data, int nData, uint8_t nCycles=1, uint8_t tickTime=1);     // starts transmission of pulses from specified data pointer, repeated for numCycles, where each tick in pulse is tickTime microseconds long
     void start(uint8_t nCycles=1, uint8_t tickTime=1);                                // starts transmission of pulses from internal data structure, repeated for numCycles, where each tick in pulse is tickTime microseconds long    
@@ -32,7 +36,7 @@ class RFControl {
     void enableCarrier(uint32_t freq, float duty=0.5);    // enables carrier wave if freq>0, else disables carrier wave; duty is a fraction from 0-1
     void disableCarrier(){enableCarrier(0);}              // disables carrier wave
 
-    int getPin(){return(config?config->gpio_num:-1);}                             // returns the pin number
+    int getPin(){return(config?config->gpio_num:-1);}                             // returns the pin number, or -1 if no channel defined
     rmt_channel_t getChannel(){return(config?config->channel:RMT_CHANNEL_0);}     // returns channel, or channel_0 is no channel defined
 
     operator bool(){                                      // override boolean operator to return true/false if creation succeeded/failed