Jack Spine writes "Engineers at the National Museum of Computing at Bletchley Park have rebuilt the Tunny machine, a key device used in decoding German High Command messages during the Second World War.
The Tunny machine took a team of three people three years to rebuild. At the end of the war, Tunny machines were broken up and the components recycled, while the original circuit diagrams were destroyed or hidden. The team had to piece together plans for the machine from odd pieces of circuit diagram that had been squirreled away by engineers, as well as from the recollections of some of the original builders,"
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