It seemed reasonable. Was targeting tube equipment but did discuss lower voltage caps also. On Mon, Jan 20, 2025 at 04:56:32PM -0500, Dave McGuire via vcf-midatlantic wrote:
I will give it a read later tonight if no one else chimes in before then.
-Dave
On 1/20/25 16:44, therenguy via vcf-midatlantic wrote:
Would the following directions be acceptable to follow for reforming the capacitors?
https://www.qsl.net/g3oou/reform.html
Randy On Jan 20, 2025, 4:39 PM -0500, Dave McGuire via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org>, wrote:
Yeah Philly is a bit of a haul from here. You could easily visit (people have visited LSSM from a dozen *countries*) but for collaborative work that probably isn't practical.
I'm afraid then that my involvement would be limited to providing some occasional guidance. First, though, no, definitely don't just plug it in. You'll need to disassemble the power supply, test and reform the big electrolytic capacitors out-of-circuit first, and only after that, voltage soak/test the supply without boards. The 8/e uses linear regulators which are ok to run without a load. There's enough current there to be dangerous, so take your time on that. I typically take several days to bring up a new-to-me 8/e power supply, and I've worked on them before.
Carefully inspect the power input cable first. It is clamped onto the back panel of the power supply, and sometimes that causes jacket wear on the cable.
If any rear panel fuses blow, do not panic. They are old enough to succumb to fuse fatigue. Replace (appropriately!) and try again.
Next, blow the backplane out with dry canned air. Not typical "air compressor air", as that contains oil. Then, pick up a tub of DeOxit gold wipes and give the card edge connectors a scrub.
You'll probably need to replace several front panel bulbs. Chicago Miniature Lamp (or VCC) 2309 are the right ones, as are Oshino OL-2. JKL/VCC 7371s will work in a pinch.
Flush the front panel board slide switches with CRC QD, then squirt in a small amount of DeOxit D5 while working the switches back and forth. Wipe off any excess.
When the time comes to power it all up, there's a toggle-in acceptance test in the manuals. (I assume you've found the manuals)
-Dave
On 1/20/25 16:24, therenguy via vcf-midatlantic wrote:
Thank you so much for getting back to me so soon. Alas, I live near Philadelphia, Reading, PA to be specific. Not quite in your back yard. I am really not sure how to begin. I could plug it in you know but I am sure that is not the way to proceed. Are you aware of anyone closer to me? I have worked on projects throughout my lifetime across the web so that might be a possibility although I am sure some of the questions I might ask would be truly from a beginner for a project like this one. Don’t really know. Decided to look into it. Ashame it sits in a closet.
Randy
On Jan 20, 2025, 4:18 PM -0500, Dave McGuire via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org>, wrote:
On 1/20/25 16:14, therenguy via vcf-midatlantic wrote:
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.
Where in PA are you? LSSM has a few 8/es, and I personally have a few more, most of which I have restored. I've been working with, on, and inside of 8/es for about 40 years.
If you're near Pittsburgh, we can probably collaborate.
-Dave
-- Dave McGuire, AK4HZ New Kensington, PA
-- Dave McGuire, AK4HZ New Kensington, PA
-- Dave McGuire, AK4HZ New Kensington, PA