In 1952, the Amplifier Corporation of America launched one of the first clockwork-driven tape recorders, ushering in a new era of battery-operated, small, and lightweight portable magnetic tape recorders. When they first appeared, the machines had no competitors, and the model enjoyed great success in the United States and beyond among semi-professional and serious hobbyist recordists. Originally, the Magnemite was designed for scientific work, in close cooperation with Peter Paul Kellogg, professor of ornithology and biological acoustics at Cornell University. Kellogg designed the recorder to be compatible with the demands and practices of sound recording in the field (that is, recording bird calls). However, the Magnemite was also used by prominent postwar sound documentary-makers such as Tony Schwartz (who traveled the streets of New York in the 1950s to record folk and street songs and document the urban soundscape); on expeditions by ethnomusicologists at the American Museum of Natural History, Johns Hopkins University, the University of Michigan, and many more; and finally by reporters at radio stations such as CBC, Radio Free Europe, and Radio Tokyo.

(source: Schellin, Roland. History of Clockwork-driven Tape Recorders. Dessau: Funk Verlag Bernhard Hein, 2009)