Problems with my Cobra 29LTD

There’s part of your problem. You need to leave the switch in S/RF mode in order for the meter to work. Don’t put it in swr or cal, the built in swr function isn’t very accurate. Of course the radio might not be transmitting any RF signal, maybe due to a cold solder joint. Might be the reason that it worked for awhile. If this would happen to be the case, then chances are your microphone maybe okay. Unfortunately it’s hard to diagnose over a forum.

 

Based on comments in the OP, I bet it's a knob/switch setting issue.

Might not be anything wrong with mic or radio

 

I know they are few and far between these days but, stop at a CB shop and have it checked out. The finals may be bad?

 

I have a 29ltd also. It will power up but no talk. Received great. Have tried new antennas,cables and mics. Gotta be the radio.

 

SWR mode is for tuning your antenna to the radio. Leave it in S/RF for daily use. Basically what NightStalker said. Any change?

 

Cal tunes nothing....All that does is basically puts the channels you select on the same ground to test to see if ant is tuned correctly as possible to that ch via swr only...Thats why you have to re calibrate on every channel you test to find out if ant needs to be tall er shorter to match what radio wants to see to allow it to work correctly..
Cal does not tune anything....

 

I know of guys who just get in a truck and crank everything wide open and expect to reach 100 mi down the road..lol..

 

Shouldnt make a diff where that switch is as to its working or not....I would invest in a better quality mic 1st before i open the radio...The asatics are not bad but a nice sra198 ranger mic is cheap but quality mic..Its a 4 pin so it will hook rite up to a cobra no prob.....
Sometimes if a mic loosens up where it screws into radio might create an issue..Snug that up every so often...

 

It sounds like a broken wire connection in the mic plug which is VERY common.

Back in my teenage CB radio days broken mic wires is where I learned how to use a soldering iron.

Plug in a different 4 prong mic and I'll bet it works or just get a baby phillips screwdriver, take the plug apart and look.