NeXT
Veteran Member
With many thanks to Alan (you know who you are), one page of the power supply schematics (AC, rectification and unregulated DC) has been located.
While this does not break down to schematics of the other regulator and control boards we can now see how the other parts of the supply are wired, plus we can confirm how the AC terminal is wired....AND how the other AC terminal strip is for configuring the supply for multiple line voltages. Turbo handy and I have confirmed using this that I am strapped for 115v service.
The page has been submitted to Bitsavers along with a few other items I've accumulated over the last few months.
What I'm finding really interesting now is that the power supply is "programmable". Remember that cable that ran from the I/O board to the power supply? Remember how on my system that cable was missing and in its place we had two deleted 10K resistors and three "Program Window" switches on the back of the cabinet? The system can adjust the voltage output of the power supply uing the I/Oboard, however you can also manually force it using those switches. I'm still a little confused as to why you would need that as opposed to "build a PSU with more stable rails" but I think it will make more sense as the regulator board is researched more.
While this does not break down to schematics of the other regulator and control boards we can now see how the other parts of the supply are wired, plus we can confirm how the AC terminal is wired....AND how the other AC terminal strip is for configuring the supply for multiple line voltages. Turbo handy and I have confirmed using this that I am strapped for 115v service.
The page has been submitted to Bitsavers along with a few other items I've accumulated over the last few months.
What I'm finding really interesting now is that the power supply is "programmable". Remember that cable that ran from the I/O board to the power supply? Remember how on my system that cable was missing and in its place we had two deleted 10K resistors and three "Program Window" switches on the back of the cabinet? The system can adjust the voltage output of the power supply uing the I/Oboard, however you can also manually force it using those switches. I'm still a little confused as to why you would need that as opposed to "build a PSU with more stable rails" but I think it will make more sense as the regulator board is researched more.
