I'm trying to put together a buddy box using two Futaba FM Conquest radios (FP T6NFK). The two radios have different TX frequency crystals. When I connect via the appropriate cable hooking the radios together, the radio that matches the receiver crystal moves the planes control surfaces as it should. However, the radio that is the slave, with the different TX crystal fails to operate the surfaces. I have the switches on both radios set the same. Am I on the wrong track with this idea? Should I have the same crystal in both radios? Can anyone tell me what I'm doing wrong? Any ideas. Thanks

This is just a wild guess, but it's something that popped into my mind when I read your post.

When you try this, have you tried with the power switch on the trainer TX in the off position? I'm not sure if this even applies to Futaba, but I once watched a buddy try everything in frustration to get the buddy box working with a different brand of radio, and come to find out it wouldn't work with the trainer TX switched on.

Thanks for the advice. Your suggestion worked. I never would have thought of this in 100 years! Regards

I'm happy to have helped