DevilishDesign

An illustration of the IBM 5150 motherboard with the functions of each chip labelled

The IBM 5150 motherboard, illustrated.

#retrocomputing

I'd put money on bad RAM from experience. Had good results piggybacking a good 2102 chip on each RAM chip in turn. Found bad RAM 4 or 5 times using this method.

We're going to do it all over again! Very excited to announce RetroFest 2026 to be held at Swindon's STEAM museum on the 30th/31st May. If you'd like to exhibit, just full in the form - and if you'd like to come, why not buy a ticket! They also make wonderful Christmas presents :) - retrofest.uk

Ahh, was it another faulty computer like Tony's Dragon? 😉

The back of a Sphere computer was a mess. Why? There was no "backplane"-- no slots. The whole system was loomed together with 14-connector ribbon cables, and the cards sat in loose slots. Moving the system could easily wiggle out a pin or two somewhere, and maybe the computer wouldn't start up.

This is a picture of the Total Microcomputer System 4000. More pictures at https://vintagecomputer.ca/total-microcomputer-4000/ #vintagecomputing #retrocomputing

This is my Total Microcomputer Model 4000 computer. Technically the last of a rare Motorola 6800 based home computer that was a pioneer in an "all-in-one" computer. Six days left on @bzotto.bsky.social Kickstarter for his book detailing Sphere Corporation here: www.kickstarter.com/projects/bzo...

Yes!! Learn about the quick rise and sudden fall of Sphere-- and then the even faster rise and fall of this mysteriously related Total Microcomputer Model 4000--in this cool book coming soon. Santo has kindly contributed information and imagery to the book. Great stories. Check it out!

Oooh, I know!! 😀

Just backed this myself :)

Go Computer Now! – The Story of Sphere Computers A book telling the extraordinary story of Sphere, a 1970s Utah personal computer maker far ahead of its time—until its sudden collapse.

Hello! I'm very proud to announce that my yearslong research project into the lost Sphere computer, corporation, and community has launched a crowdfunding campaign today for a professionally-printed hardcover book, with a compelling narrative and images! www.kickstarter.com/projects/bzo...

Hmm, tricky one. I'm guessing it originally came from a factory owned by Acorn? 🤔

Do we know where this prototype is? Museum, private collection?

JetPac was the first computer game I ever played. 16k ZX Spectrum 😍

A beautiful case with an Elektor Junior came into my collection.

With the Digitus KIM-1 on the left, center first version, right Rev A

Being a bit lazy today but I really need to sort through this box of boards

You can’t beat an MK-14 for a wonderful piece of history. I’m really looking forward to getting this one working again 😍

Ok, lets play...

Top centre - Commodore 8296
2nd Row - ADM 3A, IBM CGA/EGA Monitor, Televideo 912
3rd row - ADM 5, 2x TRS-80 Model 4s

YouTube video by More Fun Fixing It SALE DAY at The National Museum of Computing in Bletchley

The National Museum of Computing at Bletchley held a sale day to shift some of their unwanted stock and raise money for the museum. I went along to see if I could pick up a bargain.

A huge thank you to the sponsor of this video www.pcbway.com

Poor Barry! 🤣

Thanks to @tnmoc.bsky.social for putting on a most excellent jumble sale! I've picked up a couple of projects that will keep me busy for a while 😀

😍. At least it must be battery powered 😉

a close up of a stuffed monkey with a green shirt and a sticker that says $ kto ALT: a close up of a stuffed monkey with a green shirt and a sticker that says $ kto

'Firing up Kicad' ......

Only the RS232 expansion to get and I can move on to another obsession 😂

If you see this, quote with a time travel movie that's not BACK TO THE FUTURE.

A teletype printed Mandlebrot image along with BASIC program used to generate it on an Altair 8800

Write once, run anywhere! (1/2)

At #retrofest a few weeks ago I really enjoyed the setup @devilishdesign.bsky.social had with an Altair 8800 using a teletype as the user interface. He very kindly printed me off a listing of his BASIC Mandlebrot generator.

Awesome Stuff! 😀

Indeed! I thought it would have been a lot more common. Obviously not much use on the Teletype but there were far more optical readers about.

Mike has also uploaded it to his website....
deramp.com/downloads/al...

I copied the tape using my high speed reader / punch which took under a minute. Figured the optical reader was less likely to damage the tape than the Teletype :)