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Frame from Harwell Dekatron / WITCH Reboot tnmoc.org Plays via YouTube's privacy-enhanced embed

Harwell Dekatron / WITCH Reboot tnmoc.org

TNMoC
Demos
YouTube
1 HN user recommended this demo1 month2013–2018 score 1
Years with an HN recommendation, 2007–2026

Shared as a quick look at a vintage relay and dekatron computer running, along with praise for the museum.

A short clip of the Harwell Dekatron/WITCH, the world's oldest original working digital computer from 1951, being restarted at The National Museum of Computing in 2012.

1 recommendations · 2 citations · Demos

3 Hacker News comments

From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.

@duncanawoods May 2014 Recommends
on HN thread Bletchley Park row rages on as restored site opens to public with 'Berlin Wall'
Read more
TNMOC is awesome. Every geek in the UK should go. You can gift them old computing books for their growing library. Colossus is cool but seeing stuff I never knew about was more exciting e.g. The Dekatron with its decimal memory you can visually see the values, the awesome radar screens with trakker balls from the 40's or 50's, the cabinets full of early calculators (some are white spitting images of iDevices) or the early CAD system with a graphics card in a larger cabinet than the workstation. Early mainframes and minicomputers are just beautifully styled. 1 min video of the Dekatron running [this video] More info and 20 min video [link]
Short video of the Dekatron running at TNMOC.

Citations, criticism and jokes

@laumars Apr 2013 Cites it
on HN thread If It Ain't Broke, Don't Fix It: Ancient Computers in Use Today
Last month I had the pleasure I of seeing a Dekatron[1] in action (for those that don't know, a dekatron is a decimal based computer, rather than binary). The machine in question is the oldest working computer in the world (older machines like the Colossus are actually reconstructions) and uses relays rather than valves. It was a true sight to see in action as the relays spin round with a hypnotic orange glow[2] [1] [link] [2] [this video] (the video doesn't really do it justice)
Shows the Harwell Dekatron relay computer running.
@roywiggins Jun 2018 Cites it
on HN thread The Land Before Binary
The Harwell WITCH used Dekatrons, which is a device that has 10 states and can therefore store one decimal digit each. [this video]
Shows the Harwell WITCH decimal computer.

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