Quadruplex (2-inch Quad) video tape (1956 – early 1980s)

Quadruplex (or Quad) was the first commercial video tape format, introduced in the US by Ampex in 1956. Although the BBC had been experimenting with its own  video tape format, VERA, since 1952, it was not perfected until 1958 and abandoned soon afterwards.

Prior to the introduction of video tape, broadcasters used kinescopes to film television images for replay. The use of video tape allowed broadcasters to record programmes for later viewing in different time zones, or for resale, much more easily.

Quadruplex used four recording and playback heads that spun at high speed to put the video signals in transverse stripes across the tape, and this meant that the tape could move relatively slowly (7.5 or 15-inches per second). Tape reels were up to 14-inches in diameter, usually metal, and used a NAB hub. A reel containing 4,800 foot of tape could record for one hour at 15-inches per second. Audio, control, and  cue tracks were still recorded in a linear fashion near the edges of the tape.

Over the course of its life, high-band and super high-band versions of Quadruplex were introduced.

Because of its quality, Quadruplex remained the standard for broadcasting until the 1980s when it superseded by smaller (but still analogue) formats like 1-inch-Type B, 1-inch Type C, U-matic and Betacam that used helical scanning.

Smaller, 8-inch, reels were used in a portable Quadruplex recorder, the Ampex VR-3000, which was released in 1967 and could be carried on the back of a camera operator for up to 20 minutes recording time.

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