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
Telsen Electric Company Ltd Today, the Aston factory, now The Telsen Centre, has been converted by Midlands Industrial Association Ltd, a registered friendly society to provide Managed Workspace for New Start and small business SME's and managed and let by Prince Warnes Properties. www.prince-warnes.com Telsen Electric Company Ltd Telsen Electric Company was a British electronics company formed in Birmingham in 1924 by Mr. A. Macnamara at 207 Aston Road. In 1930 they moved to 56 Miller Street and shortly after moved to their new factory at the corner of Philips Street and Thomas Street. Incorporated in 1933, the Telsen Electric Company Ltd were manufacturers