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
Peavey Electronics Peavey Electronics Peavey Electronics Corporation is an American company that designs, develops, manufactures and markets professional audio equipment. It is one of the largest audio equipment manufacturers in the world, headquartered in Meridian, Mississippi. Hartley Peavey founded Peavey Electronics, one of the world's largest manufacturers and suppliers of musical and professional audio equipment, in 1965, having built his first amplifier in 1957. Since its foundation, Peavey Electronics has been privately owned, and has grown from their humble beginnings in Hartley's basement in the 1950s. In 2011, "Inc." magazine profiled the global success story of music and audio innovator Hartley Peavey