Servo problem

[Tim CooperParticipant @timcooper90034]

I have two identical servos in a model of a Russian OSA 1 boat. They are turning the gun turrets at the bow and stern. One works very smoothly, the other tends to ‘jitter’ .  Both are controlled by the same channel on the transmitter.  At present I have taken them both out to investigate.

The servos are the small SG 90 type.

Anyone have any suggestions. I think I will initially try a different servo but I think I have tried that before.

Tim

[ashley needhamParticipant @ashleyneedham69188]

Hmm…perhaps the run of the wiring is an issue…the jittery one gets too close to something?? Length of run??

Try a ferrite ring.

Er…er…

Ashley

[Tim CooperParticipant @timcooper90034]

Thanks Ashley

Now I have them out of the  boat I cant remember  if it’s the bow or stern gun! It must be my age!

I’m sure I had Ferrite ring in a drawer somewhere.

Tim

[Colin BishopModerator @colinbishop34627]

Tim

If you swap them over and the jittering stays with the same servo then it is likely the servo is at fault.

Colin

[Richard SimpsonModerator @richardsimpson88330]

If you have two servos connected to the same channel and only one jitters it sounds almost certainly that it is the servo that is the problem.  If it was anything to do with transmitter/receiver signal reliability etc. you would expect to see the same with both servos.  The first thing I would do, as Colin suggests, would be to swap the servo plugs around and see if the fault moves or stays with the same servo.

[Tim CooperParticipant @timcooper90034]

Thanks

I will (hopefully) have a look that tonight.

Tim

[Tim CooperParticipant @timcooper90034]

It seems to be the servo on the stern gun.

I have managed to take out, so I will replace it with a new one and try again.

Tim

[Dodgy Geezer 1Participant @dodgygeezer1]

I had a lot of trouble with a 9G servo on the Lark – worked fine but jittered like anything when the motor started up.  I spent ages trying to suppress interference, but eventually swapped it for an identical other servo which had no ‘interference’ problems at all.

 

The impression I get is that these 9g servos are very variable, and may exhibit odd behaviour…

[Tim CooperParticipant @timcooper90034]

I have tried a new servo on the bench, with the other original one. It seems to ok. They are on separate channels on the radio but both operated by one slider on the radio.

Tim

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