The PD 5020 came last week. I unpacked it and checked it over. The case is in pretty good shape, there are some rusted nicks, but not as many as on the case of my first 5020. I didn't see any obvious problems with any of the components, but when I powered it on, the AC light turns on, but is no output and the meter doesn't move. I haven't started troubleshooting it yet, beyond confirming the internal fuse was intact.
None of this was a surprise. The seller listed it as "For Parts/Repair" and knew enough to photograph the LM399 and pass transistors to show what physical state they were in. I bought it because the higher voltage/current precision supplies don't come up very often in working condition, or otherwise, the price was reasonable, and it came with not one, but three different printed manuals. Two different versions of the 5020 and one for the 6050.
The two 5020s manuals aren't identical, they are different versions.
The first seems to date from right around the original release of the 5020. It includes a number of pages that seem to have originated on a high-quality dot matrix printer. These cover the technical specs and parts list for the 5020. One prefaces the pages with the general description, operating instructions, and theory of operation with the explanation that the 5020 is an improved version of the 4010. The following pages are xeroxes of typewritten pages and refer to the 4010. The schematics at the end are for the 5020.
The second 5020 manual also covers the 2020b and C500. It seems to be of similar or identical vintage (Both have Rev G schematic drawings) to the scanned manual for those supplies I found online earlier this year. The image quality of my scan is much better, and they also have hidden OCRed versions of the text for searchability (not such a big deal on smaller manuals like these, but still nice to have)
I took some time to make high-quality scans of all three manuals, and I've posted them on my site (link below). I haven't uploaded them to KOBB or elsewhere yet. If someone else wants to, that's fine, though I'd hold for a week because I might post updates if I can manage to reduce the file-size significantly without a significant loss of quality. Right now they are about 30MB each.
I hope people find them useful.
If anyone has good printed manuals for any other PD supplies, it would be great if you could make good quality scans of at least the diagrams and share them. I'm personally looking for complete (or any) docs for the 2020 precision supply, and 6050a, 5005T, and 6010 bench supplies. I'd also love better quality versions of the TP340a and 2005a precision supply manuals.
Speaking of the 2005a, there is a complete manual/schematic available online, but the component layout diagram doesn't match the boards in my 2005a supplies, which both appear to have the same PCB but manufactured a few years apart. I've started trying to reverse-engineer my own annotated layout diagram, but if someone else has one, it would be great to see it and see if it saves me some trouble.