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[yamahacs80] PSU problem

2011-03-06 by Fernando Zarone

Hello, I have checked the PSU of my CS.
Testing the PSU with both of the connectors in:

Both -6,5 and +8,5 V are present.

Only affected the + and -15, 10,6 included. that are missing at the terminals.


Replaced all of the capacitors.

I can find +15 and - 15 at the level of D703 and D 704

IC 721 shows the following tensions:
pin 1: -13,6 V
pin 2: - 0,02 V
pin 3: - 0,05 V
pin 4: -15 V
pin 5: 0V
pin 6: - 0,03 V
pin 7: + 14,23 V
pin 8: + 15,06 V

Are these correct? If not, could somebody help me find the problem, following the check of voltages by my DVM?

Thanks
Fernando

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