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Charliebrown
Intermediate Member
Username: Charliebrown

Post Number: 467
Registered: 10-2002
Posted on Thursday, October 29, 2015 - 7:25 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a 2950dx tuned by copper. It is installed in a Ford Ranger with a small hd amp. and a Wilson 5000 magnet mount antenna on the center of the roof. I have a separate ground going to the amp. the Radio has a ground also. So with the mic. it came with why at times does it squeal Oh by the way the wave is a 1.2 SWR
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Tech833
Moderator
Username: Tech833

Post Number: 2337
Registered: 8-2002
Posted on Saturday, October 31, 2015 - 2:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You are getting RF from the antenna back into the mic audio.

You can:

1. Remove the "small hd amp".
2. Reduce the mic gain on the 2950DX.
3. Install bypass capacitors on the mic audio line inside the 2950DX.
4. Permanently mount a "real" antenna and stop using the magnet mount antenna.
Your radio 'Mythbuster' since 1998
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Charliebrown
Intermediate Member
Username: Charliebrown

Post Number: 468
Registered: 10-2002
Posted on Sunday, November 01, 2015 - 1:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Turned the mic gain down and it stop. Even with just the radio by itself it would do this but the mic gain down did help stop it. As far as the antenna what would you use??
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Tech833
Moderator
Username: Tech833

Post Number: 2338
Registered: 8-2002
Posted on Sunday, November 01, 2015 - 11:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Anything that mounts using a hole in the roof.

I prefer the base loaded type that use professional NMO mounts on my own vehicles, but anything from a Firestik thru-hole roof mount to a Wilson or K40 will do much better than almost any antenna on a magnet mount.

http://www.copper.com/cart/Antennas-Towers/CB-Antennas/Mobile-CB-Antennas/K40-Trunk-Roof-Mt.-Antenna?limit=100

http://www.copper.com/cart/Antennas-Towers/CB-Antennas/Mobile-CB-Antennas/Wilson-1000-Roof-Mount?limit=100
Your radio 'Mythbuster' since 1998

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