So do the hitec rx. The 7955 and 7950 servos all have had problems here. six different planes. They all jitter no matter what. We have tried signal boosters and diods.This is all on 35 to 40 centers. I have sent my 7955's back twice and they last maybe three flights before they start jittering.
There are 2 problems people refer to the most with our 79XX servos:
1. Spektrum/JR powersafe glitching. The main issue here is the signal strength can diminish with the use of long servo wires, causing our high resolution 79xx servos to glitch/jump significantly on HV (direct 2S LiPo/LiIon). You're talking almost an inch of deflection at the servo horn, if not more (especially with 3D arms). The best method to eliminate this is to use a very high quality 22awg servo extension with gold plated connectors at each end. If the problem still persists, then you may need to use a signal booster. Ailerons are generally not affected by this due to the fact that the servos use such short leads by comparison to your tail servos.
2. No load jitter. This happens to some of our 79xx servos, but not all. They will jiggle in place constantly until you apply a load to them, at which point the jitter will go away completely. Easy to diagnose this one, just apply some pressure to the control surface when the servo jitters and see if it goes away. If it does, then there isn't an issue here, the flying loads when the surface is airborne will eliminate the jitter almost entirely.
The BEST method to diagnose your problem is to apply a slight load to the control surface by hand. If the servo stop jittering, then your issue is a minimal load jitter. If they continue to do it, even with a decent amount of pressure, then
contact me here on the forums first so I can advise you the best route possible to take.
None of my servos jitter with any of my receivers (I'm 100% Hitec by obligation
).