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Unread 11-12-2013, 12:32 PM   #1
erickpl
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1997 TJ Wrangler 
 
Join Date: Jan 2005
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Adjusting SWR

Running a Cobra 29WxNwSt CB and a Firestik antenna.

Antenna got snapped off while wheeling and I replaced the missing 4' antenna with a 3' antenna off my truck. Tried to tune the SWR based on the manual for the CB, but even following those instructions, it didn't want to go below 3.

I'm wondering if something in the mount snapped off or what.

It is mounted to my Jeeperman tire carrier currently.

Any suggestions? Do I need to ground it somehow? Do I need to move it off the tire carrier? The previous 4' antenna got a good SWR (below 1.4), so I'm not sure if the shorter antenna is the problem or what...

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Unread 11-12-2013, 06:21 PM   #2
CJ7-Tim
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In your situation, excessive SWR indicates damaged components or a faulty replacement antenna.

If the system worked well before the mishap, changing the size of the antenna would have very little, to no effect at all, on the SWR.

CB antenna components are subject to wear and tear from weather, trail damage, and from everyday use. I suggest you buy new CB antenna components including coax cable, and refresh your antenna system.
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Unread 11-12-2013, 07:51 PM   #3
JPNinPA
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Agree

Use an ohm meter to see you still have continuity between the center less radio side and antenna tip. And no continuity between tip and outer shield.
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Unread 11-13-2013, 08:58 AM   #4
erickpl
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Location: northern AL
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I think I found the problem. When I swapped the parts from my truck, I forgot to swap over the plastic isolator washer/spacer that goes around the hole of the mount. Also looks like the stud for part of the mounting assembly snapped when the antenna came off. With that plastic spacer in place, there isn't enough stud to attach the next part of the antenna. Replacing those parts should take care of it.

I did some more digging on SWR on here after posting this and there were some good points that I had to check once I got home. Sure enough, damaged component and missing parts.

Thanks for pointing me in the right direction!
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