I'm one of the PDP-8 people around. What hardware skills do you have? Do you have any test equipment for working on hardware? The PDP-8/E has linear power supply but somewhat tightly packaged. The 8/E likely has deteriorating foam you need to clean out. Ideally replace but not that critical. The general approach I would take is to first check out the power supply. I like to reform the big capacitors and inspect all for leakage. This era DEC stuff the capacitors normally are still ok. Here is some info on checking out power supplies https://www.retrotechnology.com/restore/8f_fixitmay13.html After checking what you can power up the supply without anything connected and see if output voltages are reasonable. If you have a way to apply load test under load. Then pull all the cards and inspect and clean out the backplane and check for and damage or foreign objects. Start with processor cards and first field of memory and power up machine. Verify if voltages good. Then use front panel to see if you can read and write memory. If you can put in simple test programs https://www.pdp8online.com/pdp8cgi/query_docs/view.pl?id=188 You need to verify the cards are properly installed with correct top connector blocks before powering up. If those work put the rest of the memory in and run diagnostic series. Will need serial interface in computer to talk to external computer to send diagnostics. If machine isn't working either you need to pay $$ for boards to swap or do component level troubleshooting to replace bad IC's. People will help you with this at workshops but expect they aren't doing all the work. For getting support there are more DEC folks on the forum than the mailing list. https://forum.vcfed.org/index.php?forums/dec/ Anywhere you ask for opinions you will find people have different approaches. Schematics and manuals are online. On Mon, Jan 20, 2025 at 04:14:08PM -0500, therenguy via vcf-midatlantic wrote:
Hello,
My name is Randy Kaplan and I am joining this list to obtain some information and help.
I am a long time computing professional (50 years or so), have built my own hardware, and have been a software developer for many years. I also have many years of teaching computer science at the University level - not entirely relevant, just for background.
In any event I am the owner of an intact PDP-8/e that was operating once upon a time when I received it. A kind person gave it to me because they had too much hardware and needed a loving home for it. That is how I came to own it. At one point in my career many years ago I was invited to DEC to write code for a similar computer.
I am looking for someone to help me restore it to operating condition. It has not been used for many years and has been sitting and moved between many closets. I have its power supply also.
Can someone help kick off this adventure with me? I would be very interested in having a conversation with anyone who can make suggestions on how to proceed, who to contact, and if perhaps someone is interested, would like to help with such a project. I understand there are sessions help by VCF in this region, I live in PA, and I would certainly be willing to attend such a session.
Please let me know with any information you might think is helpful.
Thanks in advance for your assistance.
Regards,
Randy Kaplan