My CB use to pick up a ton of engine noise. That would increase with RPM and would have constant interference. I finally fixed that last weekend by running the power straight to the battery with RG8 coax. Now while driving I only pick up other interference from things outside my truck (for the most part I think).

I figured out that it was exterior interference when i pulled up to a light, with know interference. The pedestrian light was on walk and my radio was fine. As soon as the hand started flashing my CB would have loud static every time the hand would flash. Then when it stayed my radio kept the noise. Until i pulled through the intersection. Sometimes my radio will have hardly any static at all, and then it will have full static for few seconds.

Is there anything I can do to help reduce noise from my antenna? I believe I have it grounded fairly well. Its mounted to my toolbox, but the ground wire from the antenna I have running down in between cab and bed, inside the rocker panel, and up into the engine compartment to a grounding point. And i used some solid core wire. Is there anything else i can do besides better ground?

 

What you're probably picking up is noise from the traffic signals -- the multiplexing circuitry in the newer LED signals are quite "noisy" in the radio frequency spectrum. I get similar interference on my HAM radio equipment.

Unfortunately, there's not a lot to be done about it from your perspective -- the signal is coming into your radio from the antenna... which is precisely what is supposed to happen. Ideally, the folks in charge of the noisy signals (that are generating interference in your radio) should upgrade the circuitry in their systems or shield it appropriately so that it doesn't cause the interference in the first place.

 

You used RG8 coaxial cable for POWER?

 

Yeah, I noticed that. ...and, it's not the first time I've heard of that approach. The coaxial shield in the coax acts to prevent stray RF from entering through the power lines. Not necessarily the ideal (or least expensive) solution (I'd have simply put a choke on the power leads near where they enter the CB radio), but it works.

 

Yes i used the coax as power. I used the center core cable for the power, and used the shielding wire for the ground. It blocked a ton of noise from the engine compartment. It wasn't very expensive. It was like $0.70 a foot.

I found the info here and basically followed it:
http://www.links4jeeps.com/writeups/BasicCB/wiring.php

So basically I've gotten rid of as much interference as I can?

And any info on what a ground loop is?

 

0.70 x 10 feet = $7.00. an inline choke would've set you back maybe $3.00.


I could go into a long dissertation on ground loops... but I will save you (and others) the tedium (well, except Takeda -- he'd probably find it amusing). Here, instead, is a link to the relevant Wikipedia article, which sums it up nicely -- Ground Loop

 

Thanks, I'll give it a read