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Transmitter Ground issues

egp8111

Well Known Member
Patron
I'm thinking I have a ground issue. When I key the mike to transmit my gauges(Vans steam gauges) all jump around. I'm also getting a lot to static on the radio from my stratux. Any suggestions as the best way to ground a radio? I'm pretty clueless when it comes to radios.

Thanks

Skip
RV-4
NC
 
I’d start by looking at the coax braid/shield. It must be attached to the connectors at both the radio and antenna, and at the antenna must have a good ground path to the metal airframe immediately under the antenna.
 
SNIP….and at the antenna must have a good ground path to the metal airframe immediately under the antenna.
Not exactly correct. The antenna must be “well coupled” to the airframe. As this is RF, the simple zero DC resistance idea is not applicable. Don’t go scrapping off any paint.

To the OPs issue, not enough information to provide any coherent answer. So some questions:
- Is this a new issue or not?
- If you remove the Stratus does the problem go away?
- Have you ever connected an antenna analyzer to the feed line and antenna? If so what are the results?
- Do not overlook the radio tray antenna connection. This can easily create a lot of similar issues if the radio does not properly seat in it. For that matter if it is a 90 degree center wire solder type, look at the cover cap - it might be shorting it out (easy to do if the installer gets carried away with the soldering iron).
- Check the radio breaker. If the terminals are loose this may cause your problem.

Carl
 
Not exactly correct. The antenna must be “well coupled” to the airframe. As this is RF, the simple zero DC resistance idea is not applicable…
Carl

I need to think about this some more. If it’s capacitively coupled won’t there be an undesired phase shift in the ground plane current?
 
Yes if I turn off the stratux the interference stops but the gauges still jump when I transmit

Thanks

Skip
 
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