damiles

I bought 4 JR DS811 servos for my caliber and seem to have periodic twitching on channel 6. The servos are great and it only twitches once every 5-10 minutes.

I have a futaba radio (6XHS) and FM receiver. I have been told that the JR servos are compatible with futaba receivers. What do you think?

Vortexgen

radio interference.

FM is more prone to radio interference than PCM, the source of interference is anyones guess. usually caused by 2 metal parts rubbing together though, if its coming from the heli and not some other local source. (not much metal-metal joints on a caliber to check, engine and mounts)

damiles

Thanks, I'll check it out. The only metal piece that I added was the remote glow plug attachment. I bolted it to the engine frame and will check tighten it.

davidj

I would also suggest you look at how the antenna is routed. Make sure it is strung out full length and not doubled up on itself. Route it away from all servo's servo wires and any other electircal devices.

WillMac795

Yeah, the place where Kyosho tell you to put the antenna in the manual is not the best place IMO because it runs parallel to the extension wire for the tail servo- a possible cause of interference.

davidj

Mine is on the opposite side.

WillMac795

I use the undercarriage mounting bits and then rubber band the aerial to the vertical fin.

damiles

Well I tried as much as reasonable to get the JR DS811’s working, most of the jittering occurred on channel 6. After multiple conversations with JR support and the hobby store I went through the following iterations, without success.

In order to try to reduce the jittering on my Futaba 6XHS transmitter and 127 receiver I;

1) I replaced the servo on channel 6 with a new one.
2) I swtiched the servos to different channels on the receiver, (ie I switched servo 3 with servo 6) but the problem remained on channel 6. The throttle started to jitter.
3) I unplugged all other servos and tried each one on channel 6, one at a time, and they all jittered
4) Tested a new receiver (instructions from JR)
5) Tested a new transmitters (instructions from JR)
6) Re-routed the antenna to make sure there is no metal contact.
7) Gave up and put in Futaba S9202’s


Thanks to Tom at www.hobbyhobby.com for all the support.

I can find plenty of posts that have a similar problem with the 811’s and FM receivers but JR do not acknowledge a problem exists. If you have a Futaba FM receiver you should think carefully before you buy the DS811’s. Which is unfortunate since they do fly well when they are not jittering. Thumbs down to JR support

swmoheli

See, I tell my friend at the field all the time, "Buy a Futaba and you won't have that problem".

davidj

I see just as many problems with Futaba as I do with Airtronics, Hitech and JR at our field. To say the F word is better is just creating another flame war. One of the best heli pilots in the NW switched to the F brand and he has had several radio induced failures and crashes. All of the Radio Manufactures make equipement that most of the time do the job just fine.