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thanks but my pcb layout is different from the one in the link.

thanks but that layout is different from what I have. Towards the front of the radio there are 9 L variable inductors. That layout only shows 7. But thanks anyhow for your time.

PCB EPT360011Z Looked on google for it with no luck. This is a very early version Superstar 3900. I bought it new when I was 18 years old in 1986 Thanks for any help.

still looking for answers, thanks

still having the issue. I changed out the 2 electrolytic caps on the board but that didn't help. Still looking for answers. Thanks.

UPDATE: Problem resolved! Was a bad 1K Dynamike Potentiometer. Replaced and works like new. Bi-color LED red/green red is burnt out and will be replacing the RX/TX LED soon.

yeah a friend helped me track down the problem on the phone. shorted 2 terminals together on the dynamike pot and boom the audio was back. I had a 1K in stock over here so got it replaced the 148 is working like new again. I have never had a Potentiometer go bad on me ever. Now I know. Thanks...

UPDATE...... The Cobra 148 GTL is fixed and the problem was the 1K Dynamike Potentiometer. Put a new one in and bam! We got good loud mic audio. Thanks to everyone that responded with your suggestions.

Thanks nomad, I recapped the whole radio today and re installed TR25 and 26. I will remove TR24 and see what that does. I also have IC4 on order. Will change that out once I get it.

IC4 voltages RX Pin 1 8.3 Pin 2 14.2 Pin 3 8.3 Pin 4 0 Pin 5 14.4 Pin 6 8.3 Pin 7 not there Pin 8 0 TX Pin 1 8.3 Pin 2 13.5 Pin 3 8.3 Pin 4 0 Pin 5 0 Pin 6 0 Pin 7 not there Pin 8 8.3 Does this look normal or should I replace IC4

Also noticed that TR25 and TR26 are missing.

I checked voltage at C18 and yes there is 6V positive on both receive and transmit.

changed out C18 still no transmit audio. Also changed out all the 10V and 16V caps still the same. Might just change them all out. Think I'm going to replace the CB/PA switch next.

tested IC4 this morning. Pin 8 has 8V when Mic is keyed. No voltage on pin 4 of IC4

Looking more into the 148 I see that TR25 has been removed it's not there.

thanks, yes receives fine on the channel selected. I changed out TR22 and TR23 with no change. There is barely I mean barely audio coming through the mic. Had another radio next to it on the same channel. Super super weak audio I can hear my voice barely but doesn't move the S/RF meter at all...

yeah I checked the SM C468 ok to be in there.

I found that TR23 C945 transistor has a C458 in that location.

not the mic tried multiple ones that work on my cobra 2000

Picked up this Taiwan made Cobra 148 GTL the other day. Very clean inside and hasn't been chopped up. No extra channels either. It has a issue, no audio going through when the mic is keyed up. Also the Green/Red led does not turn red when the mic is keyed up. Also no audio coming out of the PA...