NOTSORICER - (& others)

- Is it possible when you changed the battery you hooked the negative cable to the battery before you hooked up the positive cable? (Just going through elimination process)...(not good for sensitive electronics). If so, disconnect both cables for 3-5 minutes and re-connect. Positive cable first, Negative cable last.
- Did you connect your CB power lead to one of the lugs coming off the clamp that goes to the positive battery post? If so, connect CB feed to the battery post clamp nut vs. one lugs coming off that clamp. (do this while the battery is completely dis-connected).
- a CB ground wire directly to the negative battery post clamp would be the best choice.
- make sure your antenna is grounded with a wire from the base of the antenna to a clean frame ground.
- How about installing an in-line diode at the CB feed wire coming off the battery. That way you would eliminate the possibility of feedback to the battery when the Mic is keyed. A diode capable of handling 5-10 amps should be more than enough for a Cobra 75. (radio shack) Just after the diode, (between diode and CB) I'd suggest installing a 5 amp in-line fuse.

I suggest you use di-electric grease on all connections....inside and outside the Jeep - including antenna grounds.

I haven't installed a CB yet....I just got my Jeep a week and a half ago. Just throwing out some ideas for consideration. Hope it helps.

 

Ranger492; You deserve a cookie.

 

All sounds like good ideas! Ill give feedback tomorrow.

 

Good stuff thanks, What I did notice it that it was not 100% of the time but damn close! I thought I had it after the tinfoil wrap. If this works, I might take it back out of the garage and reinstall it.
Cheers

 

I did some of the stuff you mentioned and still nada. I'll try the diode tomorrow

 

The Cobra 75 is a bit different from other CB units in that the full RF power is sent down the curly mic cable. That transmission line is not as "good" as the bigger coax normally used from radio to antenna. Be mindful if the mic cable gets pinched or crimped. This can cause the mic cable to leak signal rather than deliver it cleanly to the antenna. My mic cord is very near the dash radio and electronics, so just a little RF leakage can easily radiate into jeep systems.

As with any radio transmitter, good grounding is essential. I also added a ferrite core (Radio Shack) on my CB power wire. This helps keep any RF from back feeding into the 12volt system.


Good luck.

 

Yeah I have a full sized cobra in my JK and I did everything mentioned above and still have problem. I am wondering if everyone on here has keyless entry?! Is the frequency of the CB sending a false wave to the security system or something?!?

 

Jeeps are very prone to common mode problems with the CAN bus connecting the ECU's. You are describing a common mode problem with your setup.


https://www.jk-forum.com/forums/jk-c...erence-166099/

https://www.jk-forum.com/forums/jk-c...ing-hf-126803/

Read and enjoy info on how to cure the problems. A CB is a HF radio in the 11 meter band and if the RF from the common mode is bad enough you have these problems. My problems were more pronounced as I runn 100w into my system.

Also recheck your SWR as if you have high reflected power it can promote the problem you are describing..

 

Great! I was actually thinking about rechecking the swr as I also put my hardtop back on. Thanks for the reads, I'll get on that ASAP

 

Yeah I will read these next but my SWR is good so maybe I will get some other ideas with these other threads