Chatteriing servos

[Bizjet tech]

Hi,
I have tried to install a Flymentor to a TRex 500 (ultimate destination a very old, VERY sentimental Graupner Bell 212) but I failed
As the Bell installation has all the components on a removable plate, I set it up on the bench. The components are Eurgle 9X (original) with DS615 servos. It works perfectly on my TRex 500.
I then installed the Flymentor iaw Ivor Hills' excellent thread, powered it up and got a steady green.
It does operate, but the servos chatter constantly with an occasional random twitch when idle.
When I make inputs, the servos move in the correct direction but jerkily - as if some gear teeth were missing! It appears to under and overshoot the selection, then settles down similar to idle. When I remove the input, they return to idle as before. it is especially bad when operating the Throttle (collective pitch) as the rear servo does acrobatics! it appears to go full travel in both directions a few times before settling in the chosen position.
I swopped the radio out with a Planet T5, same as before, but perhaps not as bad.
Its just a bit frustrating! And confusing.
Thanks,
Alan

[kla912000]

Check the connections on your Rx. I tried to follow Ivor Hills directions and had the same problem with my Turnigy 9x. Turned out to be my connections on the Turnigy Rx. Try following Cruzroy's videos. They are very well explained and worked great for my Trex 450 Pro with a Turnigy 9x tx.

[pril250]

Question is whether the servos behave normally when you switch stabilization off (gain 0).

More importantly, what BEC is being used on this heli, if it is rated at 2A or 3A and is internal on the ESC it may be too low and affect the voltage to the electronics and servo. I use a 10A BEC on my 600 and a 5A on my 450.