What a 65 Year Old Computer can Teach Us Now

A project log for WITCH-E Decimal Based Computer

Document and create a modern replica of the Harwell Dekatron computer known as the WITCH

Dave's Dev LabDave's Dev Lab 09/09/2017 at 15:450 Comments

Part of the WITCH-E project's early goals was to create a web based emulator for the WITCH. This would allow us to study how to program the machine and to also understand some fundamental ways of how the machine operated. I met Justin King at an open source conference back in 2014. Justin was 11 at the time and was interested in taking on the challenge of creating the emulator in javascript. I was a little skeptical, but gave him some of the specifications. Long story short: a year later we had an emulator and Justin did a presentation at the 13th annual Southern California Linux Expo (SCALE) in 2015 on what he learned during the project! Justin did an incredible job at dissecting the programming environment and recreating the functionality! The emulator source is available via github at