CB radio interference

[JWChessell]

I've tried 4 different CB radios and several different antennas & mounts in my '03 3500; all have heavy interference noise. I can barely hear radio traffic; I can't transmit -- no one near me ever responds when I call them. My guess is it's probably the alternator. Does anyone have a suggestion/solution for a fix? I tried a search here and on the 3rd Gen-No Engs forum, but found only "push pump interference. " Thx.

 

[HBarlow]

Your post doesn't provide the information needed to give you a good answer.

Does the interference you hear from the CB's speaker sound like a motorbike and does the "motorbike" engine appear to increase rpm (frequency) with your engine rpm? If so, you need a capacitor (a noise filter) attached to your 12 volt supply wire to route interference to ground.

If your signal is not being transmitted over your antenna into the air, that could be caused by a bad antenna, an impedance mismatch between CB transmitter and antenna, or bad transmitter output.

 

[JWChessell]

Let's start with the capacitor. What should I use? Make/type/description/specs/cat#?

Thx.

 

[HBarlow]

I've been away from electronics for far too many years to advise accurately.

Go to an auto parts store or stereo installation retailer and tell them you need a noise filter for your radio. Either should/probably have one made up with proper mounting tab just for the purpose. It is a standard item that is commercially available.

 

[mrtrombley]

I had the same problem with my CB. It finally got to me, so I stopped at a Truck Stop CB shop. $25 and about 1/2 hour later I was on the road with a more powerful radio, tuned to my antenna and others could hear me and answered too. Stop and check it out.

 

[04blackcherry]

Amateur_Business_CB Radios Try this. ABC Communication. They set me up years ago with a system that worked great for me. They are in Seattle.

 

[p-Bar]

A lot of time if your antenna isn't "matched" you will hear a lot of interference this sounds like your problem . Be sure your antenna is grounded well at the mount. As Hbarlow says not enough info

 

[MChildress]

Might try running your power and ground directly to the battery. Get the antenna tuned (SWR) if you do not have a SWR meter you will need to find someone with one or go to a CB Radio shop.

 

[B.G. Smith]

Radio Shack haas the filters too, if you have the antenni wire running through the engine compartment you will pick up lots of noise. bg

 

[Crazy Horse]

Other than the aforementioned there are inexpensive filters you can easily put on your alternator to reduce whine. They are very effective. Also run extra ground wires between the bed and frame, the cab and frame, and the engine and frame. Also be sure to locate the antenna on the vehicle for the best ground plane possible. There used to be inexpensive boosters (black box) you could buy for more output, don't know if they are still out there???

Good Luck.

KBU2092
We're Gone.

 

[LandShark]

Does the interference happen just when the engine is on? If so, it is likely bad diodes in the alternator.

 

[BIGNASTY]

interference

If it were the alt. wouldn't sound like a whine seems like I had the same problem on a simi truck and it was because I had so many lights on the truck that I needed a very large Alt. to power and charge that if made the CB do strange things. The whine went up and down with RPM change. Went to the CB doctor and he put some gizmo in and it went away. Sorry I cant be of more help BIG

 

[carl07230]

try this

Try these people. Rightchannelradios.com They seem to know what they are doing. DO NOT GO TO CLAYS RADIO SHOP.

 

[JWChessell]

Gentlemen: I've been away from this problem for awhile, but thanks to each of you who responded. JWC