What could be the cause?
 

Recently I have been experiencing problems with radio interference and I can’t figure out if it is internal or external… What I am looking for is some suggestions for eliminating the internal stuff or narrowing down to what the real cause is.

Here is a description of my setup:

Futaba 6 EXA TX on Ch. 60 (Saving for a 9CAP)
Futaba 127DF RX
5 Hitec 5625MG Digital Servos for the control surfaces
1 HS-81 for the throttle
2000Mah Nimh 6 volt battery
RAM Onboard glow starter connected to a standard Y harness on channel 3
MPI Miracle Y for elevators
24 inch servo extensions for rudder and Ailerons
12 inch extension for throttle
2 - 6 inch extensions to plug the ailerons into
MPI Voltage regulator (Removed at the suggestion of someone at the field)
Standard Hitec switch
Saito 180 for power

Okay here is what happened, Yesterday while flying I experienced two glitches so I landed and removed the voltage regulator. I range tested well beyond the 100 feet for a normal range test and all was solid… After sorting out an engine problem I was running it on the ground and after about 5 minutes or so of running the controls started glitching… Rudder, flaperons, ailerons and throttle all moving without my input. I was standing approximately 2 feet from the plane with the antenna about halfway up. The glitches lasted about 5 to 15 seconds and stopped and never happened again. Only one other person was there and they were on Ch. 23. This movement was enough that it could have easily caused a crash. Others have reported getting radio hits at this field but I have flown there dozens of times without a problem. I suspect these problems are external, but I was looking for any suggestions anyone might have to offer to isolate the problem.

I suspect that the extensions might be a problem due to their length… This is my first plane of this size so I am still in the process of learning my way around.

Since I have $1200+ invested in this plane I really want to know what is going on before I lose it…

I hope someone has some suggestions

Thanks,

RE: What could be the cause?
 

Hrm, I had a similar problem. I found the cause to be my RX was within a couple inches of a servo. I've since moved it about 3 inches from any servo and have had no problems.
Also, insure that your antenna isn't close to a servo (close being within a couple of inches).

RE: What could be the cause?
 

What does the MIRACLE WYE do? Reverse the servos? I'd bet this was causing the RX to act up, might be the RX's AGC function is stirring things up... The 24" extensions are more than likely not an issue. Are you using HD extensions, wyes and so on?

What version software revision is noted on the digital servos?

RE: What could be the cause?
 

Most probable cause might be a slightly corroded connection, to small a gauge wire on the extensions or a switch that is now slightly more resistive than before due to corrosion or loosening of connections. Any small increase in the impedance of the positive or negative leads (especially the negative lead) can cause this.