Musical Instrument Repair Community

I recently got my old Nanobass out of storage and it was not responding to any midi data and the light was not lit up on the front panel. No obvious signs of life. I could not locate any schematics online but the device was of a vintage where it is relatively easy to figure out what the design is meant to be. (note the hand drawn schematic made from following tracks on the board and probing with the multimeter.) The were three power rails, a positive analog, negative analog, and a digital rail, and the problem was with the digital one. The way it was behaving was not making much sense, and after removing the smoothing capacitors and the linear regulator it became obvious that one of the rectifier diodes had died. Not quite a short circuit or open circuit, just "weird" when looking at the rectified signal on the oscilloscope. Replaced it with a spare and refitted the other components, and it booted up and started working.