N1EDM

My Feedback: (2)

How close is your transmitter to your airplane. If it is 'on top' of he plane (i.e., really close), it could cause strange things to happen. This can be checked easily by backing the transmitter away from the plane by 2-3 feet and making sure the antenna is collapsed.

Just my .02

Bob

N1EDM

My Feedback: (2)

Offhand, I would not dare to fly that plane until you have solved the problem. Another source of the problem could also be interference coming in via any of the Servo wiring.

Do you know someone with an identical radio and receiver? If you could borrow theirs at the field, and plug them in to your servos, you could see if the problem re-occurs. If it does, the problem is isolated to one or more of the servos. If not, then it has something to do with your Tx/Rx.

Is your Tx antenna screwed all the way in? It just occurred that I had a slight 'interference' problem at the field. Not exactly like yours, but close. It turns out, my tx antenna was almost ready to fall out because it had become loose. I re-screwed it in and did a range check. Problem never returned.

Hope this helps somewhat.

Bob

FIVESQUARE

I cannot help but think you have an interference problem with a metal pushrod, or something metalic around the antenna/RX.
Is you throttle rod metal? Is it close to any part of your rx?
Hvae you added any extra equipment to your radio? Battery checkers etc.
Is your antenna routed through fuse or outside???
DOC

Ladyflyer

My Feedback: (2)

You may be swamping the AGC circuit at close range. Does the glitch clear up as you move away from the receiver ?
How does the radio respond in a normal range test?

It could also be as was mentioned above a noisy spot on one of the control pots . If it is a noisy pot it would still act up at increased distances.
An out of spec component in the encoder could upset the frame rate or reset pulse and cause a similar problem. There were a few Futabas around back in the AM days with a similar problem in the encoder chip . GOOD LUCK . Hope all is well in Pakistan !

I am told JR radios have some fancy filters to prevent this

Peter_OZ

My Feedback: (1)

lotsx of good advice, all of it relevant.

May I suggest a process of half splitting and isolation.

Try different battery packs

Try different RX

Try different XTLs

Try different TX module if you can, ask a friend at the field etc.

Try removing servos one at a time to see if one is causing it

Replace switch assy or bypass it.

Try disconnecting the lead assy to each stick pot in turn and see if that isolates the problem.

Do you have long servo leads on your plane?

Maybe remove all the radio equip from the plane and try it on the bench? Could be sonething in the plane.

Good luck FWIW I like the idea of dirty pots . . . get some electronic cleaner from RS and squirt in . . . freon based works pretty well.

IF you had a CRO you could have a look at the pulse train into the encoder and out of the decoder and see if it was jumping.

cheers
Peter

BTW was the Radio gear crashed recently? IF so maybe a hairline crack on the PCB

Peter_OZ

My Feedback: (1)

BTW

AGC = auto gain control, feedback cct used to control the gain of a rx

Rx signal increases beyond a threshold then AGC limits this signal andf vice versa yada yada etc etc
per adua ad astra!


just thought I'd add that incase anyone was wondering what Lady meant

cheers !!
IT's nearly beer o'clock!

is it really downunder or upover . . .


depends on which way in space you are floating . . .