Hi, some weeks ago I've purchased a System 37 in ebay. This unit was ebay in the year 2020 and the owner was made this video too: https://www.youtube.com/watch?v=F1CZKQtaoSo
When I power up the displays shows a 1. Sometimes if I stop and start fast the display shows a 2, but in all the cases all the leds stills lighted. The voltages on the power supply are OK, and in general I the unit have a good look, I don't see corrosion or leakages from capacitors. Looking the SPU training PDF of Bitsavers/HPMuseum , looks that maybe is related with a ROM or the WCS. Somebody have more info about this error, or know if is possible get some schematics / service manual? Thanks a lot Iban
