959B help plz!

[Chainsaw660]

Help!!!
I recently traded for a 959b I knew when I received it that it had an issue. So my knowledge, skill set and tools are beginner at best. So the radio will not power on and doesn’t seem to have 8v present. I found a bad AM reg and replaced it no luck. I’ve check the 8volt reg and it test good on a component tester. Help plz. Radio is too clean to trash. Thanks in advance.

 

[nomadradio]

8 Volts? Isn't it closer to 9 Volts? Best check is to see what voltage comes out of it with the radio powered on. Just checking the transistor doesn't tell you enough.

This really sounds like a reverse-polarity episode. How does the reverse-polarity protection diode look? If the soldering on that part is shinier than the surrounding solder it suggests this part has been replaced. Only reason to do that is if the positive and negative get reversed with a fuse that was too big to protect it. This causes the protection diode to fracture, and the pieces fall away. Leaves two wire leads coming out of the circuit board with a gap between them where the diode used to be.

Maybe.

But multiple failures are not the rule for a radio that was a daily driver that broke down. And if it's a radio that four guys have each tried (and failed) to fix, who knows how many pot holes are in there?

Sounds as if "issues" may become "more issues than National Geographic".

73

 

[Dr_DX]

Have you checked the on/off switch to make sure it is working correctly? Got voltage going through both contacts when "On"?