Strange GTR 200 issue

SeanB · #1 11-22-2019, 11:03 PM

Trying to help a friend that recently took first flight in RV7. Any ideas are appreciated. Team X??? Thanks, Sean

Issue:

All of the avionics are working perfectly with one exception: My GTR-200 is receiving lots of static when above pattern altitude (above 1,000 AGL). The "Rx" is lit up, and it sounds like it's on squelch all the time. I have tried to turn squelch on and off with no luck, and in the Menu I have turned squelch from "AUTO" to 0% with no luck. It actually flew fine the first 4-5 hours, but in the last 2 hours this started. I also tried turning off individual systems using the VP-X to see if I'm getting interference (Garmin 696, ADSB, USB, Bluetooth radio, lights, fuel pump, autopilot, Dynon displays, etc.), but no luck. The comms are crystal clear in the pattern (<1,000 AGL). The static is so bad I can't communicate with anyone or listen for AWOS or ATIS.

I have no other comm radios or intercom. Just the single GTR-200.

Jake14 · #2 11-22-2019, 11:11 PM

I had a similar experience on my GTR-200. It only happened once in 3 years of use and only lasted for one flight. Chalked it up to some sort of local interference

Walt · #3 11-23-2019, 05:47 AM

USB power plug? Some of them are very noisy and will break the squelch.

g3xpert · #4 11-23-2019, 07:18 AM

Hello Sean,

Did you check the BNC connectors on each end of the antenna coax?

The "operates fine in the pattern" clue might just be lower RPM and less vibration to cause problems with a poor center conductor connection.

One of the things we see occasionally is a center pin that wasn't snapped into the connector housing.

Also, there is something wrong with this statement: "in the Menu I have turned squelch from "AUTO" to 0% with no luck."

The COM Radio RF Squelch on the COM Setup page can be adjusted from 0 (factory default that most people use) up to 10 which is the highest squelch threshold. There is no AUTO setting, so it sounds like the intercom squelch is being taken off AUTO and adjusted which has nothing to do with COM radio squelch.

Thanks,
Steve

WingsOnWheels · #5 11-23-2019, 07:35 AM

I had a similar issue, was a bad coax termination at the antenna end.

SeanB · #6 11-23-2019, 04:00 PM

Thanks for the ideas everyone. I'll pass the information along, then report back when a result is had.