This board is used in the TU56 DECtape drive and provides 38V to the motor when it is to move the tape or 18V to provide tape tension. The lower 1N5624 diode near the center failed on this board. You can see that it is a little blacker around the left end. The diodes run hot so they brown the board even when things are working normally.
Schematic of board as a scanned PDF file.
Feel free to contact me, David Gesswein email@example.com with any questions, comments on the web site, or if you have related equipment, documentation, software etc. you are willing to part with. I am interested in anything PDP-8 related, computers, peripherals used with them, DEC or third party, or documentation.
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