RE: Futaba 6xa troubleshooting
I would say that if your Tx remains on, you have a good battery
Servo twitch doesnt mean anything. I would try and loan a known working battery from a fellow flier and plug that into the RX and then check. That way you dont spend.
I may be wrong, but I think the 6EX works on PCM mode. Just check because I used to set mine to PPM when I used it on the sim I think. Its several months since I sold the 6EX so I am not sure. The 6EX doesnt come with a replacable module, so that wouldnt be a problem. Make sure you are on PCM mode. But if it doesnt work, try PPM also. You can research your RX on Tower and find out which mode it requires
If all else fails, gently pull out the crystal from the rear of the TX. It plugs in just like a USB drive but the metal pins are delicate, so be careful. Check for oxidation on the pins. Same on the RX
Oh yes, try to extend your antenne and see if that helps.
Check for breaks in the white antanne wire that comes out of your RX
If all of this checks out, you have probably checked all that you can do. The you need to take it to a proper service centre for a checkup. Futaba has good service support in the US
Ameyam