C-100. After switching on, only the radio dial lights up.

Megablast_73

Member (SA)
Hi! I decided to turn on my C-100, which hasn't been used in a long time. When I pressed the Power button, the only response was the radio dial lighting up. The Power light isn't on. The sensor isn’t working either. It also doesn’t respond when I try to play the tape deck. Everything was fine when I used it before. Although, if I remember correctly, it did the same thing to me once before. I was doing some cosmetic work on it, and after I put the case back together, it acted the same way. I remember opening it up again and not seeing anything wrong. I put it back together and it worked normally. I didn’t think much of it. Maybe it’s something with the transformer? Something that must be sensitive to certain actions when opening the case. All the connectors are seated properly and securely. Please help, because where I am, I have limited repair conditions and I’d like to prepare with a concrete plan. ...what should I check?

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Tinman

Member (SA)
An easy thing to try would be turning the selector switches and knobs back and forth a bunch of times to see if there's any difference.
You could get lucky.
 
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Megablast_73

Member (SA)
An easy thing to try would be turning the selector switches and knobs back and forth a bunch of times to see if there's any difference.
You could get lucky.
I checked... and it turns out there's no voltage coming out of the power supply board. There's only the one powering the radio scale bulb. I initially checked the transformer... it looks like I don't have any breaks in the windings. Maybe one of the diodes... ugh. I'll have to check them one by one... Does anyone have any suggestions?
 

Megablast_73

Member (SA)
I checked... and it turns out there's no voltage coming out of the power supply board. There's only the one powering the radio scale bulb. I initially checked the transformer... it looks like I don't have any breaks in the windings. Maybe one of the diodes... ugh. I'll have to check them one by one... Does anyone have any suggestions?
The fault has been found. It was a loose solder joint on the voltage switch on the transformer board.
 
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