1950

The technology is based on the magnetic wire recording system developed by Valdemar Poulsen in 1898.
Sound is stored magnetically on a thin steel wire.
An electromagnetic recording head converts sound waves into magnetic signals.
These signals are stored as magnetic variations along the wire.
During playback they are converted back into electrical signals and audible sound.
Wire recorders become popular for dictation machines, office work and speech recording.
They are also used by journalists, the military and research institutions.
A key advantage is the long recording time and the ability to reuse the wire.
However, the wire is fragile and can easily tangle or break.
Soon the technology is replaced by magnetic tape recording on plastic tape.
Nevertheless, wire recorders represent an important step in the development of magnetic audio technology.