SWR and CB Antenna

ResqFE

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I installed my Cobra 75WXST CB today and spent most of the day dialing the antenna in. Best I got;

Channel 1 was 4.0 SWR
Channel 40 was 3.0 SWR

Research saying SWR should be below 3.0 and below 1.5 for best results. Verified mount/frame grounds. Any suggestions???

Thanks
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macintux

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Those numbers are catastrophically bad. Don't try to transmit, as I understand it you'll probably fry your radio.

I would wager your antenna isn't properly grounded. Do you notice any static shock when touching your Jeep after measuring the SWR? I had bad SWR measurements and noticed shocks until I finally managed to grind off enough of the powder coating on the Teraflex antenna mount I used on my LJ.

Also be sure the feed line isn't looped tightly.
 

Bearded_Dragon

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Where did you mount the antenna and is there anything next to it, like a hi-Lift jack?
 

PaPasJP

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Looks like it isn't grounded well. Take a meter and check it.
 
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ResqFE

ResqFE

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Its mounted near the third brake light with no obstacles. I tinkered this morning and when I removed the antenna to pull in garage, was shocked. Buggin' the crap outta me but do agree its a ground issue, just not seeing it when I check it with my meter.
 

macintux

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You might enlist your local ham club. Hard to find more antenna expertise anywhere else.
 

Bearded_Dragon

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Rusty Teeth

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Did you modify the length of the coax feeding the antenna, or patch cable to swr meter is not right wavelength.

Just a thought
 

JASPER

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Make sure ground is good.. Thats number 1 culprit. I have the Cobra 75 in both my jeeps with no issues. both antennas are on on top of rear bumper make sure you grind away coating on bottom of hole.
 
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