CB radio turns on, but cant get any audio at all

Have you tried an external speaker to see if you have sound? If you have sound with an external speaker, then your internal speaker is probably bad. I have seen this problem with a cold/broken solder joint on the external speaker jack. Once i resoldered the external speaker jack, then the internal speaker worked.

 

You might also look for a switch for the speaker.

 

Squelch closed?

 

No on/off speaker switches on a cobra........Then again I don't remember ever seeing one..

squelch all the way to the left....Mic gain(dynamic) all the way to the right.....rf all the way to the right.....delta tune and t-back,cal in the middle...............Squelch cuts static noise so turn that to choice for static.....
Just for now the last two to the right center them till you get noise.....Then go to cal and follow this vid

His comment about all the power goin to ant is sorta correct but all the swr cal is telling you if your ant is to long or short.....

 

Yes you should see the needle on the meter move if the receive signal is strong enough. It would help to know if this is a new radio? Or is it an older radio that worked the last time you used it. Also try moving the pa/cb, rf/swr switches to make sure they are making good contact (unless you already tried that). Its hard to trouble shoot this type of a problem over a cb forum without knowing more about the radio.

 

Worse case senario could be a bad solder joint on the crystal / VCO section. You mentioned that the needle moves when you key the mic, but that doesn’t neccessarily mean its putting out an RF signal. Unless you verified that by using an external power/swr meter. It also could be a cold solder joint on the audio chips pins, that can cause a no receive problem too. I just mentioned to try an external speaker if you had one, since that would be a quick easy test.

 

Oh okay. Ya, this isn’t uncommon for a radio to have problems, especially if it sat in storage for many years. My first thought is that the switches and pots may have oxidized and need to be cleaned. I use a can of Deoxit 5 to clean them. If that doesn’t work, then it could be a bad solder joint somewhere, or a bad electrolytic capacitor(s). The s-meter taps off the detector circuit, so if the voltages aren’t correct, the meter won’t respond correctly either. I hope I gave you enough info to get it working again. Unfortunetly it isn’t always cut and dry. It can be a number of things that can cause this problem.