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I have -BM DC from the low current rail that is coming through numerous places on the amp board. I am very certain it is bleeding through from this line because when I remove that feed line to the board, all the spurious voltage disappears. Both right and left channels share the same PCB board. I have removed both - and + 22v DC feeds from 22 & 23. With the aforementioned -BM connected, I have -33v DC on both + and - pins 22 & 23. I also have the same reading on both left and right channel outputs ( to spkr relay). The indicated voltages on the schematic for the transistors are in the -30v range as well. I have checked resistors, diodes and transistors(go/no go test only), and I can't figure out where this voltage is finding its way to these points. I would appreciate any help you could offer, and I'll do my best to provide more info if needed.
I have -BM DC from the low current rail that is coming through numerous places on the amp board. I am very certain it is bleeding through from this line because when I remove that feed line to the board, all the spurious voltage disappears. Both right and left channels share the same PCB board. I have removed both - and + 22v DC feeds from 22 & 23. With the aforementioned -BM connected, I have -33v DC on both + and - pins 22 & 23. I also have the same reading on both left and right channel outputs ( to spkr relay). The indicated voltages on the schematic for the transistors are in the -30v range as well. I have checked resistors, diodes and transistors(go/no go test only), and I can't figure out where this voltage is finding its way to these points. I would appreciate any help you could offer, and I'll do my best to provide more info if needed.