The magnetic drum was fast but did not have the large capacity needed for data storage. John W. Mauchly and J. Presper Eckert began work in 1943 on ENIAC at the University of Pennsylvania for the U.S. Army. It was not finished during the war but in 1946 they started the Electronic Control Co. and received grant from National Bureau of Standards to build a ENIAC-type computer with magnetic tape input/output, renamed UNIVAC in 1947 but the project ran out of money. The two scientists formed Eckert-Mauchly Computer Corporation (EMCC) in Dec. 1947 and developed by 1949 the BINAC stored-program computer for Northrop Aircraft, with mercury delay line memory and a primitive magnetic tape drive. Remington Rand bought EMCC in Feb. 1950 and provided funds to finish UNIVAC March 30, 1951. It announced on June 14, 1951, the sale of UNIVAC I to the Census Bureau. It was the first commercial computer to feature a magnetic tape storage system that consisted of eight UNISERVO tape drives standing separate from the CPU and control console on the other side of a garage-size room. Each tape drive was six feet high and three feet wide, used 1/2-inch metal tape of nickel-plated bronze 1200 feet long, recorded data on eight channels at 100 inches per second with a transfer rate of 7,200 characters per second. The complete UNIVAC system weighed 29,000 pounds, included 5200 vacuum tubes, and an offline typewriter-printer UNIPRINTER with an attached metal tape drive. Later, a punched card-to-tape machine was added to read IBM 80-column and Remington Rand 90-column cards. The UNIVAC I was used in November 1952 to calculate the presidential election returns and successfully predict the winner, although it was not trusted by the TV networks who refused to use the prediction. Magnetic tape systems became the standard data storage system in the 1950s. The SAGE aircraft-warning system was the largest vacuum tube computer system ever built. It began in 1954 at MIT's Lincoln Lab with funding from the Air Force. The first of 23 Direction Centers went online in Nov. 1956, and the last in 1962. Each Center had two 55,000-tube computers known as "Clyde" that weighed 275 tons and had magnetic core memory, magnetic drum and magnetic tape storage, graphics display, and were connected by one of the first computer networks.
Evolution of the Computer
Museum of American Heritage in Palo Alto
Computer History Museum in Mountain View
