MAGSTEC explained

MAGSTEC was a one-of-a-kind computer built by ERA for the US Navy. The machine was an experiment in using magnetic amplifiers for computer use. The US Air Force later contracted Univac, who had purchased ERA, to build the same basic architecture using transistors in place of the mag amps, creating TRANSTEC.^[1]

References

1. Book: Boslaugh, David L. . 1999 . MAGSTEC and TRANSTEC . When Computers Went to Sea : The Digitalization of the United States Navy . https://books.google.com/books?id=Mi8MhzheOokC&q=magstec&pg=PA113. Los Alamitos, California . IEEE Computer Society . 113–114 . 0-471-47220-4 . 99-24731 . While Philco was developing SOLO for the National Security Agency, the U.S. Air Force encouraged ERA, under an independent research and development (IR&D) agreement, to develop an experimental computer similar to BOGART but without solid state diodes. Magnetic amplifier logic circuits were to be used throughout, so ERA named the resulting computer MAGSTEC. When ERA's successor, Univac Division of Sperry Rand Corp. completed the machine in 1956, they found it to be faster and more reliable than an equivalent vacuum tube computer, however, it was suspected that magnetic amplifier circuits were probably slower than the speeds that might be obtained with transistors..