Elliott 405 documents

A friend of mine recently sent me a packet with a few documents belonging to his late father. The father managed the LEAPS computer centre for the GPO in the 1960s, which had two National-Elliott 405 machines. I thought the esteemed members of this parish might find the docs interesting. I’m going to be making PDF versions available on my blog, and there’s an introductory post here: https://mansfield-devine.com/speculatrix/2022/01/elliott-405-a-fascinating-glimpse-into-vintage-computing/

More to come soon.

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A great post and a promising start - thanks!

From it, I’d like to highlight this silent movie about the installation in 1959 of one of these National Elliott 405 machines, at Reckitt & Sons in Hull (a cleaning products company.)
INSTALLING OF A NATIONAL 405 COMPUTER AT DANSOM LANE

You’ll see several wheeled transports, fork lift action, a mobile crane, and lots of unsafe hands-on unpacking and installing. You’ll see a magnetic storage drum and a motor-generator set. You’ll see underfloor cables being pulled, and a lot of wiring being finished off. And you’ll see a flowchart on a blackboard, and some data entry, and much more besides.

I also found this post, in French, with some nice photos and details:

(I would think that the delay storage corresponds most closely with today’s registers, the drum storage with RAM, and the tape and disk storage with our filestores.)

There’s a working Elliott 803 at TNMoC which is well worth seeing - and also a 903 with an upcoming online event to have a go at programming it.
https://www.tnmoc.org/events/2022/02/23/programming-the-edsac

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Good point. Could you do me a favour and leave a comment to that effect on the blog? I’m happy to be corrected and I think it would be useful to have the correction with the original.

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Sure thing, done! (Peter Onion once spent most of an afternoon chatting to me about the 803, and showing the supersize book of schematics for it.)

Here are some photos, including the console, very clean looks almost like plastic