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CelGen Studios @celgen.org · 15h

This thing has been torturing me for the last month. It received a full cleaning and the power supply got an inspection/service. The voltages so far seem to all be there and it sort of clears itself but the logic is still so dead it won't even initialize and display 0's. I have no manuals/schematic.

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CelGen Studios @celgen.org · 15h

Does anyone have past experience with debugging Canon’s nixie calculators, specifically the 164p?

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Reposted by CelGen Studios

gloriouscow.bsky.social @gloriouscow.bsky.social · 2d

I've decoded the NEC V20's group decode PLA.

This PLA takes an 8-bit opcode (and two mode signals) as inputs and produces 14 status outputs that control operation of the CPU.

These status signals will hopefully explain some gaps in functionality that the microcode doesn't cover.

#retrocomputing

The NEC V20's group decode PLA being extracted in MaskRomTool

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CelGen Studios @celgen.org · 1d

If you ever want to own a microcomputer, remember that recapping a power supply is a LOT more expensive.

Over $300 just for the six bottle caps and another two dozen of the comparatively little axial caps Four Phase use everywhere else.

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CelGen Studios @celgen.org · 1d

What kind of a meteor crashed into the handle to bend it that much?

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CelGen Studios @celgen.org · 1d

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CelGen Studios @celgen.org · 2d

We lost Dennis Ritchie on this day 14 years ago.
Father of the C programming language. Co-developer of Unix.

Never forget the man who helped build the foundation of modern computing, yet whose passing was so brutally overshadowed by a sleazy salesman who disowned his own daughter.

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CelGen Studios @celgen.org · 2d

The full video is below.
It's amazing how this was 40 years ago and a lot of the computers we now see as vintage and collectible were still barely 25 years old while others were so new they were not even considered out of date yet.

www.youtube.com/watch?v=Pg5u...

1985 Boston Computer Museum Tour (TCM) Computer History: tour of the former Boston museum

YouTube video by Computer History Archives Project ("CHAP")

www.youtube.com

CelGen Studios @celgen.org · 2d

Watching an old video from the former Computer Museum of Boston and they had an Apollo Guidance Computer on display that while they did a beautiful job emulating it on what looks to be a compact mac with a touchscreen overlay, the touchscreen is so badly out of calibration it's completely unusable.

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CelGen Studios @celgen.org · 3d

Re-using the liquid cooling system also required me to find out the reason why it was shelved in the first place. It kept losing coolant and now I was able to find out the radiator had multiple pinhole leaks, however because its copper I could fix them with solder. Boom, no more losing coolant!

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CelGen Studios @celgen.org · 3d

Some photos over the last year as I began building the system for the LAN Party, testing to make sure it all worked and committing everything to the case as I was repairing cracks and gluing on magnets to support the liquid cooling system.
Thanks again to @thetechknight.bsky.social for the PSU!

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CelGen Studios @celgen.org · 5d

For tomorrow's video I'm wrapping up with VCF MidWest and doing a show and tell about a system I brought with me.

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CelGen Studios @celgen.org · 6d

….hey, as long as it works. 🤷‍♂️

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CelGen Studios @celgen.org · 8d

I was away for a weekend and I determined now to start filtering job searches into its own folder because this is just nuts.

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Reposted by CelGen Studios

Adrian's Digital Basement @adriansdigitalbasement.com · 8d

Yesterday, I was lucky to be able to spend a couple hours at the Connections Museum with Sarah Autumn.

I had a stupid grin on my face the entire time!

Even after a couple hours, we just barely scratched the surface of what's there. It's unbelievably awesome.

www.telcomhistory.org/ConnectionsS...

Me and Sarah at her favorite spot in the museum. This is used by technicians to diagnose and fix issues within the switches.

Sarah explaining how the entirely electro mechanical sender works

This video phone works and is from 1970! Needless to say it was a huge flop but you could make video calls.

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CelGen Studios @celgen.org · 8d

The many angles of a CM-2, courtesy of the Interim Computer Museum.

icm.museum

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Reposted by CelGen Studios

Adrian's Digital Basement @adriansdigitalbasement.com · 8d

I had a blast hanging out at the Interim Computer Museum Saturday night. There were a bunch of things I had never seen in my life.

Thanks @celgen.org for being my model!

icm.museum

Punch card sorting machine. Quite mesmerizing!

The Thinking Machine is a sight to behold.

This PDP has a few faults at the moment, some stuck memory bits I think.

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CelGen Studios @celgen.org · 9d

And somehow I am now on a list with the CBSA. Is it a bad list? No idea. 🤪

The border guard recognized me as “the guy with the clean old station wagon full of old computers” and had apparently processed me in 2024 because again, how to declare value on this stuff.

No issues getting home. 👍

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CelGen Studios @celgen.org · 9d

#vcfpnw2026

ITS HAPPENING!!!!!!!!

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CelGen Studios @celgen.org · 9d

Day 2 is alive and well!
The show runs for a few more hours so drop in if you can!

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CelGen Studios @celgen.org · 9d

ICF day 2 has me started with splicing leaders on 9-track tape.

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CelGen Studios @celgen.org · 10d

Cheap hotels and computer shows go together like Velcro.

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CelGen Studios @celgen.org · 10d

Thank you to Mike Brutman as well for loaning me his Xircom parallel Ethernet adapter and a floppy disk setup with his DOS TCP stack so that I could demo an IRC client running on one of the GRiD’s as well!

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CelGen Studios @celgen.org · 10d

Day 1 is well underway and the tables are looking great! Don’t forget that the Interim Computer Festival is also tomorrow if you can’t make time before 6pm today!

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CelGen Studios @celgen.org · 10d

Thank you to Josh and the Seattle Retro Computing Society for loaning me some of their own GRiD laptops and a printer to salvage most of my table for the show!

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