Classic analog board 0 Volt

[dochilli]

I have two classic analog boards that show 0 volt at the floppy port. I measured the volts at cp22 and one had 45 Volts, the other had 0 volt. At a functioning board I measured 90 volts, but I read in another thread that there should be 300 volts. Anay ideas, where I can find the defect part?

 

[dochilli]

Short summary:

Board nr. 1 had a defect TDA4605. I changed it and the board came back to life.

The second board had 0 Volts at cp22 and the large electrolytic caps. I found that the power cord connector on the board was cracked. I resoldered it and the board worked. It was the first time that I saw a cracked power connector. All three solder joints were broken!