Builders: | George R. Stibitz, Samuel B. Williams.
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Place: | Bell Laboratories, 463 West Street, New York.
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Dates: | Authorized 1938.
Construction begun April, 1939.
Completed October, 1939.
Began operation January 8, 1940.
Demonstrated to the public September 11, 1940, Dartmouth College.
Dismantled 1949.
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Cost: | Approx. $20,000.
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Technology: | 400-450 relays, 10 crossbar switches.
6-8 panels (approx. 8' x 5' x 1').
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Arithmetic: | 8-digit precision (10 internally), range ±0.99999999.
Binary-coded-decimal, excess-three code.
Fixed decimal point at beginning of number.
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Programming: | Fixed program to perform the four operations of complex
arithmetic.
Sequential operation; i.e., each relay or set of relays would commence
its operation immediately after the relays before it in the sequence were
finished. There was no synchronizing clock.
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Speed: | Approximately one minute per multiplication.
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Input/Output: | Ordinary teletype with a modified keyboard. Teletype
connected to processor by a multiple-wire buss; therefore remote operation was possible.
Up to three teletypes were connected to the arithmetic unit; an interlock
permitted only one to be active at a time.
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The Complex Computer used relays as its basic building block-that was its "anatomy."
Its appearance was deceptively simple: a metal rack for the relays, teletype keyboards for
the input and output.