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Discussion Starter · #1 ·
I bought a cobra 75 wx st for my TJ, with a 4' firestik antenna and I set it up fairly well I assumed. I purchased it from right channel radios and followed their instructions very well, I drove to see some friends in AZ from San Diego and stopped in the middle of the flat desert near El Centro and tuned my SWR and got a reading of 1.3 on channel 1 and 1.4 on channel 40, which I assume is a good SWR (I was told anything under 1.5 is good) and I have the power wired directly into my unswitched wire that is located in the glove box. my antenna is mounted on the driver side tail light and I gently zip tied the excess cable in a figure 8 fashion, however when I use the radio I have to turn the squelch up to around 3/4's to not get any static, bringing my effective range to almost nothing. any help on what I may have done wrong!
 

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... I gently zip tied the excess cable in a figure 8 fashion ...
My guess would be that the coax is interfering with itself, being crisscrossed like this.

Just my 2 cents.
 

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Discussion Starter · #3 ·
Hmmm, I will look into it, I only did it that way because several people said to do it this way to reduce interference. I will look at alternative ways to secure it.
 

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Hmmm, I will look into it, I only did it that way because several people said to do it this way to reduce interference. I will look at alternative ways to secure it.
???

No. Loosely coiled with no sharp bends or kinks. Probably safe to coil no smaller than a few inches diameter.

Straighten everything out and test again, make sure you haven permanently kinked your Coax.

The antenna depends on establishing a good ground from the shielding of the cable/connector to the truck at or very near the mount.

good luck,
 

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You've done nothing wrong. AM modulation will receive static when no signals are present. Just the way it is. Most communication radios have fairly sensitive receivers which helps with weak signals, unfortunately that makes them receive noise very well too.
 

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You've done nothing wrong. AM modulation will receive static when no signals are present. Just the way it is. Most communication radios have fairly sensitive receivers which helps with weak signals, unfortunately that makes them receive noise very well too.
X2^^^
Also you don't need more coax than it takes to get to the antenna. Having a predetermined length of coax is fairy tale.
 

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So it's normal to have to turn up the squelch 3/4's of the way?
It's not abnormal. You might try a shorter coax and see if that helps.

I have the same setup you're running, except my 5' Firestik is on the Drivers taillight. Where do you have your remote box? I have mine under the center console, and a 9' coax run under the drivers seat and along the tub rails got me to the antenna with about 3" to spare. With that, I've been able to get it down to a 1.2 on channel 1 and 1.4 on channel 40. The way things are set up now, the highest I've had to turn my squelch is about halfway, and that was in downtown Seattle where reception is crap to begin with
 

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Discussion Starter · #10 ·
my remote box is in the glove box, and I was sent an 18' coax with a good amount left, it goes from the glovebox under the dash through the foot well, and then hugs along the tub rails.
 

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my remote box is in the glove box, and I was sent an 18' coax with a good amount left, it goes from the glovebox under the dash through the foot well, and then hugs along the tub rails.
How much is left coiled up? If you can get away with using a 12-foot cord, try that
 

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Coax length won't affect the SWR neither will it affect where the squelch shuts the hiss off. Just adjust the squelch just past the point where the hiss shuts off and you're fine.
 

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and I have the power wired directly into my unswitched wire that is located in the glove box.
Is this a wire straight from the battery? I had tapped off of the cig lighter and anytime I had the fan on it would bring the noise floor up. And then when I turn on the LED spots it would get even more worse. So I re-ran the power wire straight from the battery and it is way better, but still some.


Just a thought, set the squelch with only the radio on, no engine running, no fans, lights etc, then start the jeep see if the noise breaks the squelch then fan then lights etc etc.
 

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To eliminate most common sources of noise, CB and ham radios should always be powered directly from the battery and not from the cigarette lighter plug, random fuse locations, etc..
 
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