 In 1956-57, Remington Rand St. Paul Univac-division of Sperry Rand Corporation, had designed and built a transistorized "test" computer for the United States Air Force, which was called "TRANSTEC".It was designed by Univac's St. Paul engineer Seymour Cray, and used the Philco's high-frequency surface-barrier transistors in its computer's circuitry design.This was Univac's first computer designed with transistors and was used to test transistor logic circuits and also its speed and reliability, compared to magnetic amplifier (MAGSTEC) and vacuum tube circuit computers.