I've almost finished my robot. The receiver is accepting the signal, but I have a few problems. First of all, for some reason, the antenna on the transmitter (fully extended) has to touch the antenna on the receiver for anything to happen. Also, no matter what I do with the transmitter, it only causes the servos to 'twitch.' In other words, the servos move forward, and then back. Finally, if I wiggle the antenna (on the receiver), if it moves, or occasionally by itself, the servos twitch by themselves. What should I do?