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
CMC Electronics CMC Electronics CMC Electronics Inc. () is a Canadian electronics company and part of Esterline Corporation's Avionics & Controls business segment. The company's principal manufacturing facility is located in Montreal, Quebec, with additional facilities located in Ottawa, Ontario and Sugar Grove, Illinois. The company was founded in 1903 as Canadian Wireless Telegraph Company of Canada by Guglielmo Marconi. In 1925 the company was renamed Canadian Marconi Company. In 1948 English Electric purchased the UK based Marconi Company and in 1953 acquired 50.6% of Canadian Marconi Company. In 1968 English Electric was itself purchased by The General Electric Company plc (GEC),