Scota4570

Radio Futaba 6EX-2.4
RX Futaba R617FS
Servos Hi Tech 645MG (5 of them)
The ailerons are on channel 1 and 6 using the flaperon option.
Dual 5-cell Nimh batteries

The right aileron servo (Ch. 6) jitters and is not consistently responsive. I swapped it for the rudder servo and it seems better.
The offending servo works great on 4.8V with an old FM RX. Could it be that this one servo is more sensitive to higher voltage? Might it have something to do with digital vs. low speed analog mode on the RX?

Rodney

If the servo is on an extension, check the connections as a poor connection can cause this jitter. Also, a poor connection anywhere in the servo lead can cause this; make sure there is no contamination on any of the connectors.

Scota4570

I'll check that. I could put a dab of DeOxit on each connector and work them a bit. The extensions are heavy duity wire with EMS ends I made up. All connection have shrink tubing on them. Everything is brand new.

Scota4570

So.........

I tested the servo at various voltages. With different RXs also at differetn voltages. With and with out extensions. At 6V it jitters near the end of the throw and gets warm to the touch. It draws more current while jittering.

I called HiTech. They said send it in for repair or replacment because it sounds like it is bad. There you go.

Consitering shipping costs I'll probably trash it and forget about the whole thing. I thought that HiTech servos were good stuff. I am surprized to get a bad one.

Texastbird

Every company sends out a dog every now and then. My buddy had a name brand high end servo bad right out of the box some time back. Don't lose confidence in the 645s, I have some on a plane with many many trouble free flights.