The National Museum of Computing has got a new, two-ton computer to its collection — the world’s oldest. After a three-year restoration project at The National Museum of Computing, the Harwell Dekatron (aka The WITCH for Wolverhampton Instrument for Teaching Computation from Harwell) computer was rebooted on 20 November 2012 to become the world’s oldest original working digital computer. The supercomputer was used to aid scientists in the 1950s, who were crunching large numbers — though it took a while.
The 2.5 tonne, 1951 computer from Harwell with its 828 flashing Dekatron valves, 480 relays and a bank of paper tape readers will clatter back into action in the presence of two of the original designers, one of its first users and many others who have admired it at different times during its remarkable history. By 1957, the computer had become redundant at Harwell. For every two digits, the computer took 10 seconds to calculate.
After 15 years being out of commission, the computer has been restored. ‘The Witch” is now back to the way it operated in its heyday.