In checking out the power supply I noticed that the power supply wiring didn't match the schematic in the maintenance manual. As shown on the left side of this marked up schematic the memory relay wires to terminal 6 and 7 are swapped. On the right is a later version on the schematic which shows the changed wiring for the read write output. The inhibit output was modified similarly. Apparently this supply was made to a revision between the two available schematics. The changers modify how the supply is discharged when the computer is turned off. I don't know why they made the changes.
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