Stibitz, George R.

SUBJECT AREA: Electronics and information technology

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b. 20 April 1904 York, Pennsylvania, USA

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American mathematician responsible for the conception of the Bell Laboratories "Complex " computer.

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Stibitz spent his early years in Dayton, Ohio, and obtained his first degree at Denison University, Granville, Ohio, his MS from Union College, Schenectady, New York, in 1927 and his PhD in mathematical physics from Cornell University, Ithaca, New York, in 1930. After working for a time for General Electric, he joined Bell Laboratories to work on various communications problems. In 1937 he started to experiment at home with telephone relays as the basis of a calculator for addition, multiplication and division. Initially this was based on binary arithmetic, but later he used binary-coded decimal (BCD) and was able to cope with complex numbers. In November 1938 the ideas were officially taken up by Bell Laboratories and, with S.B.Williams as Project Manager, Stibitz built a complex-number computer known as "Complex", or Relay I, which became operational on 8 January 1940.

With the outbreak of the Second World War, he was co-opted to the National Defence Research Council to work on anti-aircraft (AA) gun control, and this led to Bell Laboratories Relay II computer, which was completed in 1943 and which had 500 relays, bi-quinary code and selfchecking of errors. A further computer, Relay III, was used for ballistic simulation of actual AA shell explosions and was followed by more machines before and after Stibitz left Bell after the end of the war. Stibitz then became a computer consultant, involved in particular with the development of the UNIVAC computer by John Mauchly and J.Presper Eckert.

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Principal Honours and Distinctions

Institute of Electrical and Electronics Engineers Emanuel R.Priore Award 1977.

Bibliography

1957, with J.A.Larrivee, Mathematics and Computers, New York: McGraw-Hill. 1967, "The Relay computer at the Bell Laboratories", Datamation 35.

Further Reading

E.Loveday, 1977, "George Stibitz and the Bell Labs Relay computer", Datamation 80. M.R.Williams, 1985, A History of Computing Technology, London: Prentice-Hall.

KF