[sin]

after numerous experiments with 3 transmitters($40) the way i did my calibration is:

1. press the button 'til the green and red lits up.
2. after both lights turned off pull the trigger.
3. when the red light lits up push the trigger all the way(full reverse) - this is the trick part.
4. when the red light turns off just let the trigger stay there at full reverse.
5. when the green light turns on put the trigger on its neutral position.

hope this helps.

i think this works only for the mini-x version 1 electronics.