Servo Wiggle?????
 

K, I bought a used JHH F-16 and when I hook up the receiver and try things out (servo's came with) I get wiggle on the control surfaces. Its like a car does when it has bad shocks and somebody jumps on your bumper. up down, up down, up down. then center. Its doing it on all control surfaces. Now, I tried a Multiplex receiver and a Hitec rx, same thing. The servo's are futaba 9501's. I have a 2 cell 2200mah Li-po battary attached with a regulator to take it down to 6volts. What the heck, over???

Dale

PS Radio is a Multiplex Evo 12

RE: Servo Wiggle?????
 

Can't find Futaba 9501 servo anywhere...an older digital maybe? Morst Futaba digitals aren't rated for 6v. 4.8 volts only. Switch to JR 8511/8611s or try with 4.8v pack and see if that fixes your twitching.
Woody.

RE: Servo Wiggle?????
 

How are you excercising the channel in question ?

I remember that when I got my first high-spec servo (digital, coreless), I hooked it up to the aileron channel of my RX to test it, thumbed the stick all the way over and watched the servo move, then when I let go of the stick and watched the servo go back to centre, I though something was wrong since the servo did exactly what you describe - it went past centre, back again, oscillating very slightly before stopping.

Took me a moment to realise that the problem was that I was letting go of the stick and the springs on the stick were actually making it do this damped-oscillation ; the only reason I had never seen this before was that the cheap and slow analog servos I had used before had so much inertia that the servo itself damped out the momentarily varying position that was being sent due to the stick position settling down.

Do your tests with you keeping control of the stick at all times so that the springs aren't bouncing it around ... or connect the servo to your retract channel or similar, where there is no such problem of spring-induced variation of the servo position info.

RE: Servo Wiggle?????
 

Thanks for the input but that isn't the problem. I've had a few digi's before and this has never happened. Since the first post I've done everthing from switching channels, removing y and extensions wires, trying different servo's and the like. I've even taken my Li-po off and installed a 4.8v nimh instead. I get the situation every time I plug in the second aileron servo. If I switch channels and put one of the servo's on a channel by itself it is fine, but when I use both servo's, the one acts up. I'm not sure what it is but how about this. I have a JR 10x on the way with a rx and 8411's. I'll work it out then. I don't think I can trust these servo's so I'll either chuck em or try them in a spad.

Dale

RE: Servo Wiggle?????
 

The servos are probably fine if they work right in other configurations. Could be a Rx mixing problem. Are you saying this only happens when using flaperon configuration?

RE: Servo Wiggle?????
 

I'm having the exact same problem. One aileron servo wiggles and doesn't seem to function properly when hooked up but is fine if tested separately.

Is the flaperon function causing the problem, is it the extensions on the aileron servos, etc.? Did anyone figure this out?

RE: Servo Wiggle?????
 

You have a poor connection somewhere probably in the Y lead to the ailerons

RE: Servo Wiggle?????
 

Actually....2/3 of the Futaba digitals listed on the Futaba site ARE rated for 6v.

RE: Servo Wiggle?????
 

Sometimes if the servos haven't been used for some time, they move about & jitter. It is caused by a dirty pot in the servo through lack of use. Usually a few minutes of rapid movement using the transmitter gets rid of the problem. If not, then replace the servos.

RE: Servo Wiggle?????
 

This sort of problem has been aired on here a number of times, it always comes down to the use of Y leads in the end, especially with Digital servo's, solution get rid of the Y leads.

Mike

RE: Servo Wiggle?????
 

RE: Servo Wiggle?????
 

I have regular servos and no Y leads. Servos are plugged into channels 1 and 6 with flaperon activated. Servos "wiggle" back and forth before centering after stick deflection. All aileron and flaperon settings are correct according to Futaba instructions.

RE: Servo Wiggle?????
 

The best way to investigate this, is to eliminate each variable, set a new model No in the Tx and reset everything in that model memory so it is blank, use one battery plugged into the Rx direct and then attach the two servo's concerned into seperate channels, if it still happens you probably have a dirty pot in your Tx or servo, if it does not happen set Flapperons and try again, if it then happens you have a rouge set up on the Flapperon mix in the Tx, keep going until you have the problem solved or found and eliminated, its the only way to test each variable, unless you have another Tx you can try.

Best of luck
Mike

RE: Servo Wiggle?????
 

Concur totally with Mike.

RE: Servo Wiggle?????
 

I wonder if Dale (digit) ever figured out what the problem was, considering this thread was from 2006.......

As for the poster who dug the post up, Ditch the flaperon mix to start with and see if the servo's do the same thing. I don't know Futaba stuff at all, but I did have a similar issue on a Kingcat stab when I switched to 8611's, turned out there it was the Y harness but as you say you're not using a Y harness I have no idea. Are you using extensions with amplifiers in them? That could be causing the problem if you're running 2.4.

RE: Servo Wiggle?????
 

I have long extensions but no amplifiers and it's not a 2.4 radio. I'm in the process of trying to eliminate variables but I can't even get the stupid things to replicate the problem consistently. I've adjusted all the flaperon, flap trim, and aileron values up and down the scale with no changes and have tried different servos. They work fine in other channels but when I hook everything up according to the manual the aileron servos don't function properly and continue to wiggle back to center.

It's a brand new Escapade 61 and I can't fly it of course unless I'm confident all the controls are working.

RE: Servo Wiggle?????
 

Try a different receiver and then if all else fails, try a different transmitter. I had almost the identical problem years ago when I was flying Futaba with a Merdian pattern ship. I swapped servo's, receivers, batteries, leads etc. Sent it all back to Futaba (this was an 8UAP) and they said the aileron pot in the transmitter was failing. This was after losing another Meridian to a then at the time brand new Futaba Conquest 7 radio. I ended up switching to JR. Having said that, anything can fail, but if changing servo's or receiver doesn't take care of it, I'd almost bet it's the pot in the transmitter, especially if it's intermittent.

RE: Servo Wiggle?????
 

This happens when you have bad pots in a servo. My old 9304's were notorious for this.