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- Oct 10, 2002
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C4P (the one you put in for C12P) is certainly toasted since it was running 70V or so over its rating. You'll have to replace it before the negative supply will come up properly. You shouldn't power up with the old C4P in place and it won't be good for the regulator to power up with C4P removed so . . .
After C4P is replaced with a good cap . . .
This still could be hard to troubleshoot because other components in the HV supply could also be damaged. This would be C8P, C9P, C10P, and C11P along with all of the multiplier diodes.
Try removing C12 to see if there is any voltage at its positive terminal. There will be a lot of AC here, but you should still get a DC reading. If this DC voltage is mV then I've got to think about what to do.
Can you do some probing around with the power applied? If so:
1. What is the TH voltage?
2. What is TL+ voltage?
3. What is the voltage at the + terminal of C8P
4. What is it at the + terminal of C9P
This will make a start.
After C4P is replaced with a good cap . . .
This still could be hard to troubleshoot because other components in the HV supply could also be damaged. This would be C8P, C9P, C10P, and C11P along with all of the multiplier diodes.
Try removing C12 to see if there is any voltage at its positive terminal. There will be a lot of AC here, but you should still get a DC reading. If this DC voltage is mV then I've got to think about what to do.
Can you do some probing around with the power applied? If so:
1. What is the TH voltage?
2. What is TL+ voltage?
3. What is the voltage at the + terminal of C8P
4. What is it at the + terminal of C9P
This will make a start.