CB Radio Interference

[Storm Chaser]

I was wondering if anyone has encountered this slight problem with a CB. Every time I apply the brakes, a second later there is a few seconds of static that comes through the radio after I disengage. It happens on all channels. I ran the coax and power cord under the front of the dash and is rather close to the dianostic port. I have no symptoms when I transmit. This seems to be the only thing affected. Any ideas?

[GPan099]

It's possible that it is coming from the 12v power lead.

The "cleanest" power is a direct line (fused) from the battery or fuse panel.

Where did you tap into for power?

Also maybe a bad ground.

[Storm Chaser]

I ran a pos and neg lead directly to the battery because it is a high power 10/11 meter radio. Ran the leads through a hole in the firewall that I created and underneath the I/P directly behind the diagnostic port. The radio receives and transmits flawlessly. It is a strange type of interference immediately after I disengage the brake. I may try to reroute the wires tomorrow but it sounds like the radio is picking up some type of internal communication from within the vehicle. Thanks. Any more ideas?

[f5fstop]

Could be interferrence with the brake booster motor (H3 does not use vacuum for boost, it uses a motor). It is located right near that big grommet in the dash panel. Can you re-route the wire away from the brake system?

This may not be the problem, but it is the only thing I can immediately think of with only three cups of coffee in my system.

[Storm Chaser]

Now that sounds like the likely culprit. The interference does have the characteristics of a motor and the coax/power crosses that area. It may be hard to relocate but I will take a look. Have some more coffee and thanks.

[Big Z]

Might try installing a Filter.