Programmable calculator to use magnetic strips were the HP-41C and TI-59. Continuous memory does not lose its content when the calculator is switched off. With continuous memory the user can, for example, change batteries without losing the entered programs. Compact Cassettes offered a simple, inexpensive alternative to magnetic cards. Usually, an interface module, such as the Casio FA-1, was used to connect the calculator to an ordinary cassette recorder and digital data were encoded as frequency-shift keyed audio signals. Sharp and Hewlett-Packard also sold dedicated micro- or mini-cassette recorders that connected directly to the calculator. These set-ups, while being more practical and
English Electric English Electric The English Electric Company Limited was a British industrial manufacturer formed after the armistice of World War I by amalgamating five businesses which, during the war, had been making munitions, armaments and aeroplanes. It initially specialised in industrial electric motors and transformers, railway locomotives and traction equipment, diesel motors and steam turbines. Its activities were later expanded to include consumer electronics, nuclear reactors, guided missiles, military aircraft and mainframe computers. Two English Electric aircraft designs became landmarks in British aeronautical engineering; the Canberra or B-57, and the Lightning. In 1960, English Electric Aircraft (40%) merged with Vickers (40%)