CN Antenna noise

[KaRanger]

I installed a Uniden 520xl with a 4' Firestik. Its great when the trucks off, but a disaster once u start it.

Ive narrowed it down to the antenna, when I take it off it quiet. Its mounted to a tool box, I ran a grounding wire from the mount down to the frame but it did nothing.

I have the coax wire ran down the in between the cab/bed, under the drivers side along the frame, and then up in through auto shifting linkage grommet and in.

Is it just picking up everything along the way from my fuel pump, alternator? How do I go about fixing this?

help

 

[407Link]

replace the fuel pump or get one of the boxes that cancels sounds like that

 

[4x4junkie]

I found the fuel pump makes a lot of noise on mine that the antenna picks up.

I put 3 small .01µF disc capacitors across all the leads right immediately where they go into the pump & sending unit on top of the tank (you'll need to remove the 6 or 8 bolts holding the bed down to get to it). This cut the noise down to being just barely perceivable.

 

[KaRanger]

replace the fuel pump or get one of the boxes that cancels sounds like that

http://www.amazon.com/ProComm-Noise-Clipper-Radio-Reducer/dp/B0042AK9TQ?tag=959media-20

Like one of these?


And could a bad ground on the tool box cause extra noise? Ive been trying diffrent lengths/spots to ground it to but its not making a diffrence.

 

[4x4junkie]

Doubtful there's a bad ground if you're grounding it in different spots and it's not making any difference.
You're just going to have to get under there and put something on the wires to suppress the noise from the pump's motor (they all do it. There's nothing there to suppress the noise from the factory).

 

[KaRanger]

Thanks for the info, ill try to get something around the wire to shield it.

Ok Ive noticed i am getting some interference from the engine to, the sounds going up with my RPMS. Friend of mine said i need a "ground loop isolator". I can only find ones from Stereo, can I splice on of these into the ground for my CB? or are there any better ways?

 

[4x4junkie]

Is it like a "pulsing" (ignition) noise picked up by the receiver? Or is it a high-pitched whine noise in the speaker? (alternator)