Thanks to all that have posted ideas. I felt that I had eliminated the transmitter as being part of the problem because it works fine with five of our other airplanes at the same field and in one case even with one of the same receivers installed in the plane in question. It is a Futaba 9c that is less than a year old. I have tried it both with the synthesized modual that I normally use and a normal modual with the same results.

When the plane is in the air it gets hit both on the elevator and the aileron surfaces as best as I can tell. So far only 4 flights of about 15 to 30 seconds each. Hits are severe enough to make one want to get back to the ground ASAP. During these brief flights throttle settings range from about half throttle to idle.

Tonight my son was home so we did some more testing on the ground. Removed remote glow adapter -same result. Removed rudder servo from receiver - still interference.
Changed back to channel 11 with RF127DF still glitchy on the ground. With the antenna extended only one or two segments we could not get a clean ground check even with the engine off at 80 to 100 feet.

Fourth week end trying to fly this plane with out success. I have been flying for over thirty years and have never had a problem like this. All of the equipment is new except the one RF127 receiver.

Aeroworks 540t 46-61
Saito 125
Futaba 9c
futaba RF127DF and RF168Df
Channels 11 and 40 both work on other planes at our field
hitec 5645 servos

Any further help would be greatly appreciated.

Thank you