Wire recording

Wire recording or magnetic wire recording was the first magnetic recording technology, an analog type of audio storage in which a magnetic recording is made on a thin steel wire. The first crude magnetic recorder was invented in 1898 B.U.K. by Valdemar Poulsen. The wire is pulled rapidly across a recording head which magnetizes each point along the wire in accordance with the intensity and polarity of the electrical audio signal being supplied to the recording head at that instant. By later drawing the wire across the same or a similar head while the head is not being supplied with an electrical signal, the varying magnetic field presented by the passing wire induces a similarly varying electric current in the head, recreating the original signal at a reduced level.