[NSRCA-discussion] Chasing glitches (was Lost Abbra)

[Fred Huber]

I'm currently chasing a RX problem which nearly cost me the plane.

Many flights with no radio problems.  (had a couple of instances of covering comming lose on the ARF....)
Goofe up and caused a servo to over-travel stripping a gear, so I replaced the servo.  3 flights after that with no radio issues.  Then I stuck in an RX volt-watch device.  2 more flights no problems.

Got to flying it around the last time it was in the air and the plane started glitching, so I landed.  When the plane stopped at the end of the runway (less than 75% of my normal antenna down range check distance) controls went absolutely nuts, including throttle. (which is really strange because its an electric model)

When the glitching occurs, it pulls the volt-watch meter down to the lowest indicating light.

The plene:
Quest 3D G2
AXi 4120/18 using Jeti 70 amp ESC
Hitech Supreme 8 RX
4 Blue Bird 621 servos (90 in oz)
2700 mah 4-cell NiCd RX battery (ESC has no BEC function)
2 X 3s 3600 mah LiPo for 6s power (appx 11 to 12 min of Sportsman level Pattern per charge)

Polks Tracker-III TX

I've swapped out every servo (I have 4 spares)
I swapped to a Futaba 127 DF RX and to a Polks Seeker-II and a Seeker 6
Changed the switch harness to an MPI heavy duty with volt indicator.
Changed to a 900 mah 4-cell NiCd for the RX
Tested with and without the volt-watch

Only had one good range check since the problems started with an RX anywhere near the airplane, that was with just the motor and the rudder servo plugged in. (original RX)

Wierd part... the whole radio system works fine if I pull it out of the plane and lay it on the ground similar to how its laid out in the plane., including the long servo extensions for ailerons and elevator an the motor system. (put it back and the glitching is back)  This is repeatable with any combination of the servos I have.

The other RX's tested all work in the planes they are normally used for.

TX operates all other planes I have with no issues. (I only use 2 frequencies even though I have a few synth RX's and the TX is synthesized)

Current antenna down range check is 50% of my norm, so I don't dare fly it.  

I've been thinking of putting together "glitch busters" ( http://www.uoguelph.ca/~antoon/gadgets/gadgets.htm ) for use on the long lead channels, but can't see why I should need them if the system worked for appx 3 months without them.  I have had a plane with exgensions that added up to right  at 1 meter where the devoces cured problems , but those existed from first time the radio was plugged together.
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