Originally Posted by Lead Wings
Photos of trainer connection.
Note the trainer PCB has some “squiggles” (very technical term) etched into it – on the other side of the board it has them labelled as L2, L3 etc. Isn’t L the designation for inductance?
Yes, those are inductors. At this frequency all that is needed to make an inductor is a few squiggles of pc line as you see. They are probably used as rf chokes to keep the rf frequency out of the trainer cord.
You can solve your voltage problem by connecting a 7805 voltage regulator between your transmitter supply and the rf module. You can get those at Radio Shack for about a buck and a quarter. They usually come with some sample schematics for connecting them.