[Steven Dew]

Have a FM Dual conversion radio.
Went to the field the other day, ranged checked
before flying. It test at about 175 feet. I flew.

Later, when I was about to put it in the air again.
Now, I always start up with the antenna down and
put it up just before taxing on the field. Anyway, I
noticed that the all the servos were jittering. After
much testing, we realized that another pilot, next to me,
that was flying on channel 54. I am on channel 38.
I moved up my antenna up one segment and all was fine.
I ranged checked again with one segment up, Okay.

Later in the day we did another check. When I was flying,
I had the other pilot turn on his radio, briefly, to see if
it would affect me. The result was that there was no effect.

Now, I intend to send my radio in for checking out. My belief
is that the jittering should have not happened in the first place.
Or is possible for various reasons and considered not to be
a problem?

[Gary Maker]

Sometimes if a servo pot is dirty, the servo will jitter trying to seek the centre position. It may have simple cleaned itself. Just a thought!

Being that far seperated in channels I doubt that the other pilot was causing you interferance. It could have just been a temporary glitch. If the problem didn't reappear, I wouldn't worry too much about it. But do be thourough in doing your range checks and if the problem does come back, then I would consider getting your radio checked.

There are indeed so many things that can cause a temporary glitch!

[Steven Dew]

Update. Just for interest sake.

Since the occurence when I got the interference
on Channel 38 from channel 58 as explained earlier.
Two other flyers had the same experience from the same
person's radio [channel 58]. One was on channel 39 and the
other I'm not sure right now. However, based on
these events, we have concluded that the radio
on 58, some how is spattering all over that range.
Apparently, he has some minor radio problems at times.
We have advised him that he should consider getting
his radio checked. We all would all like to know the results.
In the mean time, WE won't fly when he is.
Speculation is maybe his Tx crystal.?!

[ronm]

From what you say, HE should not be flying until he has his radio checked!

[Gary Maker]

As Ron says, if there is indeed reason to believe it is the other fellows radio that is causing the problem, then speak to your CFI or safety officer and have a chat with the fellow and have him have his radio checked. If he brushes it off or does nothing and continues to fly, the CFI or safety officer can ground him until he shows proof of a passed inspection!

As much as one hates to think about causing hard feelings about doing something like this, it is a very important safety concern. If his radio causes another plane to glitch and/or lose control and someone gets hurt or causes property damage, imagine how bad you will feel knowing what caused it and you said nothing!!!!

I know personally, I would welcome someone telling me that they narrowed down a problem that may be caused by me or my equipment! I would rather be inconvienenced for a short time while getting my radio checked out rather than causing someone to have a serious accident!

Safety is everyone's concern and responsibility! Speak up and do something about this concern for your own and everyone's safety!!

[Steven Dew]

We have talked to him today.

[lightning]

Just a thought - do you have access to a frequency scanner at your club : :
It would be a lot more convincing if you could show the guy what happens when he turns on his TX.
'corse it might also prove he's not the culprit too

[Steven Dew]

Actually. he is a very nice and understanding
person. There are no hard feeling, rather
more concerned for his own model safety,
although, I checked with him again today,
using the same conditions as before
and there was no problem. We both had the
same setups??????????? : :

[Argus]

Soooo....how much testing does it take to throw a transmitter into a rage, and is a transmitter rage anything like road rage.... . Just kidding....

Intermittent problem... hmmmmmmm. Loose antenna or lead? Maybe a component or two starting to go bad?

Wade

[Kelly W]

Electronics can be very flakey and the gremlins inside may not show themselves when you're looking for them. I'd still consider having the radio system(s) checked over. That’s always cheap insurance...

One other possibility... I'm a mech engineer, not electrical, so the lingo may not be 100% here... I was once told that these systems basically amplify a broad range of RF, then filter it down to the frequency you are using to harness the signal. If someone’s TX is near your RX and your TX is off, far away, or the ant is down, your RX may be getting saturated with RF from the other radio, such that it can’t clearly read your signal. If you move it a reasonable distance away (say the other side of the pits for example), the problem should go away. If you move away, and he's still causing trouble on your channel, then there's probably something wrong...

Hope this help...
Kelly