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[Steve Holden]

D'Arcy J.M. Cain wrote:
> On Tue, 28 Oct 2008 10:06:31 -0400
> Steve Holden <steve at holdenweb.com> wrote:
>> Bizarre though it may sound in this age of integrated circuits there
>> really was a storage device that used a cathode ray tube to store (IIRC)
>> a kilobit of information. It detected, by the use of a capacitance plate
> 
> A kilobit?  One tube would carry one bit.  Imagine the size of today's
> computers if we were still using them.  In those days you were lucky to
> get 4 Kbytes of core memory.
> 
> In those days they would have techs walking back and forth along
> pathways inside the memory banks with shopping carts full of tubes
> replacing them as they burned out.  Programs had to be prepared to deal
> with the fact that bits could go dead at any time and functions would
> run multiple times and hold an election to determine the correct answer.
> 
Sorry, you are thinking of bistable multivibrators. I was talking about
the Wiliams tube store:

  http://ed-thelen.org/comp-hist/SEAC-Williams-tube-desc.html

which I now see stored a half-kilobit in its SEAC implementation. They
built them to be cheaper and more compact than the single-tube bit store
(the single tube actually held two triodes in it), which would be used
for accumulators and the like - the fast stuff.

I don't ever remember programming to cope with equipment failure,
however. Did you make that bit up?

regards
 Steve
-- 
Steve Holden        +1 571 484 6266   +1 800 494 3119
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