Gentleman - I recently acquired a Hangar 9 P47 150, never flown, with a Fuji 32 EI Gas engine, run once. Whenever the engine is running, one of the two Flap servos moves, randomly, up and down, slightly. The servo on the other Flap does not jitter. I am using an HD reversing Y harness. I put in a new Y harness and switched from JR 537 analog servos to DS811 digital servos. The same Flap jitters. The servo leads go directly from the wing to the Y to the JR 649 receiver. I am using a JR9303 on PCM. I switched from a 6 volt battery to a 4.8 volt battery. No change. I moved the receiver and servo extentions around. No change. It does not happen when the engine is off. There are 10 servos in the plane. Each Aileron has it's own servo on different channels. The same with the Elevators and the Mechanical Retract serovs (S791).

Is it possible that the ignition could be glitching just one servo on a particular channel?

I am waiting for the rain to stop so I can put the plane together and try some other things. I have flown the plane 4 times. The engine runs great and starts easy. No problem with range, with or without the engine running. I first noticed the Flap moving on the second flight, but I thought the Transmitter was swamping the receiver. Not a hint of irregularity while flying, but since I put in the DS811 servos, the Flap deflection is just a little too much.

Any ideas on how to Diagnose this problem?