Weird CB problems T680

Focus on the antenna, that's where the problem is. Factory antennas SUCK.

Others here can give you details on what to do, you will need coax, and a mount, leave the right one in place.

 

You changed the radio and antennas. Did you change the coaxial cable between them?

 

If the coax or antenna is bad, the swr is going to be bad or very high reading. How are you checking the swr? You need to use an external swr meter with a jumper coax cable to get a decent swr reading. If you were using the cobra 29's built in swr meter, that isn't good. The internal swr meter feature on the cobra radios are very inaccurate. I've seen them show an swr of 1.2 with a broken pl259 attached to the antenna, not good. Beside the mike, another thing that will cause the meters needle to not move would be if you have the s/rf/swr/cal switch in swr mode. It needs to be in s/rf mode, not sure if your new radio has the same switch. Also the cb/pa switch needs to be in cb mode. If the meter is stuck or bad, or a cold solder joint can cause this problem too. But you ruled this out by trying a new radio. What you really have is an RF ground problem which is very common on these newer trucks. But with a new radio, antenna, and coax, and the needles still don't move on your new radio, that is a mystery to me, because even without an antenna hooked up to the radio, and quickly key and release the microphone switch, the needle should still move. As far as the RF ground problem, there is a lot of good info on other threads on this forum to help you. You can go to k0bg.com and click on the link called bonding to get an idea what to do.

 

WHOA!!!

I AM GOING TO MAKE THIS ALL CAPS TO GET THROUGH.

ONLY HAVE THEM PULL ONE AND ONLY ONE CABLE - COAX - ONLY TO THE LEFT SIDE, REPLACE THE MOUNT OR JUST USE A NEW ONE.

DO NOT HAVE THEM PULL A NEW CABLE TO BOTH SIDES, THIS WILL NOT FIX THE PROBLEM!

 

There could be corrosion on the antenna mount also.

 

That's true, but that wouldn't keep the needle on the s/rf meter from moving on both radios. That's what doesn't make sense to me. The needle should move a little (in calibrate mode) even with high swr, although the OP claims the swr is fine. That's why I asked "how are you checking the swr?, but he didn't say.