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Old 5th Dec 2017, 3:30 pm   #2
ukcol
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Join Date: May 2003
Location: Harlaxton, Lincolnshire, UK.
Posts: 3,944
Default Re: Geoff Tootill Computer Pioneer

Quote:
Originally Posted by dave walsh View Post
.........complete with valves rack mounted upside down.....
Great lengths were taken with early thermionic valve based computers to get the maximum reliability out of the valves used. The valves used in Colossus at Bletchley Park were run 24/7 to avoid the failures associated with heating up and cooling down for example. I wonder if the designers thought the valves may be slightly more reliable operated upside down for some reason? It may, of course, simply have been that access to components for servicing and testing was more convenient with the chassis upside down.
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