What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Transmitting on 1 side unbearable static until warm

Stan Bahrns

Active Member
Cannot transmit only static

My Push to talk on both sides has so much static on both sides now that I am not able to transmit at all but receive very well.
I have checked all the connections on the headsets & wiggled everything I can think of even pulled out the skyview but didn't find anything. Does anyone have any idea where or what I should do to find the problem? It seems like there is something that switches when the push to talk switches are pushed that don't switch completely. If anyone has had any problem like that? If so it may help me know where to stare looking for the problem.

Thanks Stan Bahrns
RV12 148 hrs
RV7A 378 hrs
Effingham Ill
 
Last edited:
Hi Stan,

It would be helpful if you were to also give us a little more info about your RV-12 so references to the proper wiring drawings can be made. Is it an older RV-12 that has the audio panel or a newer version using the GTR 200 radio? If the GTR 200, perhaps try something easy ... unplug it and firmly re-seat the radio in the enclosure.

In addition to what Julian asked .... curious, is the audio from the SkyView also noisy in your headset until things warm up ... or is the noise only an issue when you press the push to talk button?

It almost sounds like you may have a flaky grounding or perhaps a pin in one of the connectors that is not fully seated … when the connector gets warmer the pin expands and makes better contact?

For troubleshooting connector wiring, I have made up some test wires with various combinations of the male pins and female receptacles crimped onto the wires. These really come in handy trouble shooting wiring issues with DB style connectors.

My suggestion would be to first remove the Options connector from the AV-50000A module and ohm out the wires on pins 24, 25, 26, 27, 28, 29 to their respective left and right headset/mic jacks. The readings between the left and right side should be nearly identical … try to wiggle the wires a little while looking at the meter to verify the connections are electrically solid. Also verify that the headset jack mounting nuts are tight and that the jack body is not grounded at the seat pan … the insulating washers should be in place and verified to be isolating the body of the headset jack from the seat pan. While at it I would also make sure the push to talk button pins 1 & 3 on the Fuselage connector are providing a solid ground to the radio.

If all seems well between the Options connector and the headset/mic jacks and the isolation washers are doing their job, I would work on verifying all connector pins associated with the audio circuits are fully seated in the connector body. This can be accomplished by using male and female connector pins inserted into the appropriate connector positions to see if the male pins or female receptacles inside the connector body move during the insertion … a sign the pin or receptacle is not fully seated in the connector body. Use your appropriate wiring diagram and follow the audio/mic circuits from connector to connector testing the audio circuit with your test wires. Also, make sure to test the appropriate pins on the AV-50000A module’s connectors and taking ohmmeter readings.

Keep working your way back to the radio if you have the GTR 200 (which I'll assume you do). Pop the radio out and inspect it's connector as well.

Hope this helps somewhat ... and that you discover your issue.
 
Last edited:
I have the SL-40 Garmin Radio

I have the Garmin SL-40 radio which works fine except for the bad static when transmitting. It's like there is switch somewhere that tries to but don't completely switch most of the time. Occasionally it will transmit ok but most time it is a ratcheting static when ptt is pressed.

Thanks Stan
RV 12 618B
150 hrs
Dues paid annually
 
If your push-to-talk switches are cheap Radio Shack ones, you might try new switches. I replaced mine with part number ISR3SAD600.
 
The PTT is simply closing a connection to ground, telling your radio to transmit.

Try turning off all electronics except one radio. If that is clear, turn on one item at a time until you determine which causes noise. If clear with the engine off, pull the alternator CB to keep it from charging and see if that helps.

If you have noise regardless of the configuration, I'd suspect you have an issue with antenna wiring and/or grounding. You'll need a SWR meter to troubleshoot that end of the system.
 
Also presuming that you have the garmin GTR200 radio, you can enable a soft key for pilot PTT, and then click the PTT on the radio instead of control stick By doing that you can work out if its a wiring issue to the radio or radio and antenna related
 
I just had a similar problem. I cleaned the terminals on my headsets both male and female and this fixed the problem. sometimes its just simple things!
 
Antenna?

I had a similar problem (I think) a while back. What fixed my problem was the connection from the lower comm antenna to the antenna itself was frade and once I replaced that connection with a new connector the problem went away.
 
I found the problem

Evidently when I last installed the radio I didn't didn't get the lug on the screw that draws the radio into its mount in the right slot & even though it was tight it didn't draw the radio in far enough.So it evidently made good contact with the pins ok for about 125 hrs & then started losing connection intermittently & finally not at all. Was an easy fix once I figured it out. Probably would have saved a lot of work if I would have just pushed in on the radio in by hand.
 
Back
Top