Videotape

Videotape is magnetic tape used to store video, and usually sound, as an analog or digital signal, read by a helical-scan or, in early formats, a transverse-scanning head, because a video signal's high bandwidth would otherwise require impossibly fast tape speeds. Bing Crosby Enterprises gave the world's first demonstration of videotape recording in Los Angeles on 11 November 1951, a device developed since 1950 by John T. Mullin and Wayne R. Johnson that produced images described at the time as blurred and indistinct on standard quarter-inch audiotape run at 360 inches per second. The BBC built its own experimental Vision Electronic Recording Apparatus from 1952 to 1958, and RCA demonstrated color and black-and-white magnetic recording at its Princeton laboratories on 1 December 1953, but neither reached broadcast quality. Ampex introduced the first commercial professional broadcast-quality machines, the two-inch Quadruplex or Quad format, on 14 April 1956 at the National Association of Broadcasters convention in Chicago. CBS Television first used an Ampex VRX-1000 at its Television City studios on 30 November 1956 to delay a Douglas Edwards newscast for the Pacific time zone, and on 22 January 1957 NBC's Truth or Consequences became the first program broadcast to every American time zone from prerecorded videotape. Quad remained the broadcast standard for roughly three decades until replaced by helical-scan formats, while consumer videocassette formats, led by Sony's Betamax in 1975 and JVC's VHS in 1976, later fought the videotape format war that VHS ultimately won.