Bally -54 Rectifier Voltage Question and other issues

Keroppi

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Bally -54 Rectifier Voltage Question and other issues

Please help:

I (~newb) just finished completely rebuilding this board (other than the connectors, which were completely untarnished and all toned good), as well as both HV and 5V sections of the SD/VR...

All voltages on the rectifier are within 'The guide's' range except TP3 (12VDC) which meters out to ~9V with J3 unplugged and ~11V with J3 plugged (more on the 'J3 plugged' reading in a moment). I have verified the primary is providing good 12VAC to the board. I have also double checked my solder connections...Is it possible (likely) that the rectifier is bad out of the box? Or is it within (somewhat) reasonable range for no load? 'The guide' says 11-16V; and most everything I have read indicates it should be high without load if anything, but most everything also says don't trust 'no load' voltages...

...SO I figured 9V was low, but voltage was present, so I carried on to the next step: Unplug MPU J4, Remove SD/VR J1, J2, J5 and Fuse; I MISSED THE PART ABOUT UNPLUGGING THE SOUND BOARD (CHEAP SQUEAK)...

...Powered up to check voltages again and (for reasons not-yet-troubleshooted) quickly cooked the R51 resistor in the HV section...

...(Tracking back again) TP3 on the rectifier shows nada with the cheap squeak plugged in; I unplug the cheap squeak and I get my ~11VDC...so I assume my 12V path on the cheap squeak (or less likely, wiring) is shorted to ground (amazing powers of deduction lol).

...I'll get to the sound board later, but I figure now is a good time leave it unplugged and come here to the seek the knowledge of the wise to find out if I should be troubleshooting the SD/VR, or (even worse) back to the rectifier.

Thanks in advance!!
 
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