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
Vestax Vestax The Vestax Corporation was a Japanese musical instrument, turntable and audio equipment firm founded by Hidesato Shiino in 1977. The company started by designing and manufacturing electronic guitars. In the 1980s, Vestax produced multitracks recorders and later move to making DJ mixers, professional turntables, compact disc players and signal processors. Debt troubles lead to the company's bankruptcy at the end of 2014. The Vestax Corporation of Japan began in 1977 as a designer and manufacturer of electronic guitars. In the 1980s Vestax introduced a series of cassette-based multitracks, including the Vestax MR66, to challenge established products from Fostex, Yamaha