Quote:
Originally Posted by Zsuttle
This PVM is probably the latest TV I've ever done (ca 1989), I recapped the full set after it was having some vertical issues, that basically rendered the set unusable. Now it doesn't turn on, and something is dragging the PSU voltages down. I think it's around 200 caps that I replaced in total. What's the best way to start troubleshooting and isolating the fault?
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Is there a schematic on line anywhere?
My first two guesses is a solder bridge or a cap in backwards. BTW, sometimes the board is legended with the polarity backwards. I've learned to check the board markings as I remove a cap or diode to make sure it's printed correctly.
A quick (but certainly not exhaustive) check is to check the resistance to ground of every positive terminal of the caps. If any of the positive terminals read zero ohms to ground, the cap is either in a negative voltage circuit (normal reading) or it's in backwards.
This all presupposes that the caps in question are tied to ground one way or the other.
John