Magnetic tape

Description

A magnetic recording medium used to reproduce sound, data, and images. The idea for using magnetism to record electrical signals was introduced by Danish engineer Valdemar Poulsen in 1900. Magnetic tapes were later developed during World War II. Magnetic tapes are composed of a thin plastic (Cellulose acetate or Polyester) ribbon substrate coated with a thin layer of magnetic particles, usually Ferric oxide (Fe2O3) along with small amounts of Chromium dioxide (CrO2). The electrical signal is fixed as a magnetic imprint on the audiotape which can later be read and converted back into an electrical signal. Recordings can be easily erased, permitting the tape to be reused many times without a loss in quality of recording. Prerecorded audiotapes were used in music studios in the 1950s and became popular for homes and autos by the mid 60s. By 1951, magnetic tapes were used as auxillary storage devices for the UNIVAC computers. Ampex Corporation introduced the first video recording device to use magnetic tape in 1956.

Synonyms and Related Terms

audio tape; video tape; magneetband (Ned.); bande magnétique (Fr.); Magnetband (Deut.); nastro magnetico (It.); banda magnética (Esp.); magnettape (Sven.)

Sources Checked for Data in Record

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998

• Encyclopedia Britannica, http://www.britannica.com Comment: "magnetic recording." Encyclopædia Britannica. 2005. Encyclopædia Britannica Premium Service 15 Mar. 2005 .

• Website address 1 Comment: Multilingual Glossary for Art Librarians at http://www.ifla.org/VII/s30/pub/mgl.htm