Just a note to say be careful with the 1 in. Antenna wire on your 624 rx don't twist it or bend it . Just leave it alone . I had one fall out in flight . It was only held on by a couple of threads of wire . The throttle dropped off twice (fail safe) and let me know something was wrong. I re- soldered it back on . Not a good idea. Mine had no range after I did that ?????