secretspy711
Member
I've installed a Uniden CXM760 in my Jeep Wrangler Unlimited. My problem is that I hear noise corresponding to engine RPM over the radio. When the engine isn't running, the noise goes away. But when I'm driving, I have to turn the squelch to a setting of 4 or 5 (max = 7) to stop the noise. Turning up the squelch effectively reduces my range, doesn't it?
Another "workaround" that seems to work is by pressing the LO/DX button. Pressing this once turns on "local1" and quiets the noise somewhat, but does not eliminate it. Pressing it a 2nd time turns on "local2" and the noise disappears and I can turn the squelch all the way down to 1, and the noise is still gone. But doesn't this severely limit my range? I don't think this is the intended purpose of that button.
I'd rather fix the real problem rather than use these workarounds, but of the two, is it better to turn up the squelch, or turn on local2 and turn down the squelch?
I've tried everything I can think of. The CB itself is mounted in the passenger-side footwell.
1.) Power and ground to the CB is wired directly to the battery.
2.) Coax is routed from the CB, along the passenger side floor under the carpet, across the tailgate hinge, to a mount attached to the spare tire holder.
3.) I have a ground strap running from one of the antenna mount bolts, across the tailgate hinge to the body tub using a self tapping screw. The presence of this ground strap does not seem to make a difference though. I've scraped off the powder-coat on the mount to ensure a good ground.
4.) SWR is good. 1.0 on channel 20 and ~2.0 on 1 & 40.
5.) I've tried 2 different antennas (Firestik and Firefly, both 3-foot). I also have a 4-foot Wilson Flex that I haven't tuned yet, but connecting this one still produces noise.
6.) I put ferrite chokes on the power leads.
7.) I tried powering the CB from a completely separate battery sitting in the passenger seat, and the noise is still there while driving.
8.) When I disconnect the antenna, the noise goes away.
9.) I bought new RG8X coax and hooked it up, without tucking it under the carpet. Made no difference whatsoever.
#7 and #8 are telling me that the noise is coming in through the antenna, and not the power leads.
Is there anything else I can try? Banging my head against a wall here.
Another "workaround" that seems to work is by pressing the LO/DX button. Pressing this once turns on "local1" and quiets the noise somewhat, but does not eliminate it. Pressing it a 2nd time turns on "local2" and the noise disappears and I can turn the squelch all the way down to 1, and the noise is still gone. But doesn't this severely limit my range? I don't think this is the intended purpose of that button.
I'd rather fix the real problem rather than use these workarounds, but of the two, is it better to turn up the squelch, or turn on local2 and turn down the squelch?
I've tried everything I can think of. The CB itself is mounted in the passenger-side footwell.
1.) Power and ground to the CB is wired directly to the battery.
2.) Coax is routed from the CB, along the passenger side floor under the carpet, across the tailgate hinge, to a mount attached to the spare tire holder.
3.) I have a ground strap running from one of the antenna mount bolts, across the tailgate hinge to the body tub using a self tapping screw. The presence of this ground strap does not seem to make a difference though. I've scraped off the powder-coat on the mount to ensure a good ground.
4.) SWR is good. 1.0 on channel 20 and ~2.0 on 1 & 40.
5.) I've tried 2 different antennas (Firestik and Firefly, both 3-foot). I also have a 4-foot Wilson Flex that I haven't tuned yet, but connecting this one still produces noise.
6.) I put ferrite chokes on the power leads.
7.) I tried powering the CB from a completely separate battery sitting in the passenger seat, and the noise is still there while driving.
8.) When I disconnect the antenna, the noise goes away.
9.) I bought new RG8X coax and hooked it up, without tucking it under the carpet. Made no difference whatsoever.
#7 and #8 are telling me that the noise is coming in through the antenna, and not the power leads.
Is there anything else I can try? Banging my head against a wall here.