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Vision Electronic Recording Apparatus

From Wikipedia, the free encyclopedia

Vision Electronic Recording Apparatus (VERA)
Media typeMagnetic tape
EncodingSystem A
Developed byBBC
UsageVideo production

Vision Electronic Recording Apparatus (VERA) was an early analog recording videotape format developed from 1952 by the BBC under project manager Dr Peter Axon.

History

In order to record high frequencies, a tape must move rapidly with respect to the recording or playback head. The frequencies used by video signals are so high that the tape/head speed is on the order of several meters per second (tens of feet per second), an order of magnitude faster than professional analog audio tape recording. The BBC solved the problem by using 52-centimetre (20 in) reels of magnetic tape that passed static heads at a speed of 5.08 metres per second (16.7 ft/s).

VERA was capable of recording about 15 minutes (e.g. 4,572 meters) of 405-line black-and-white video per reel, and the picture tended to wobble because of some jitter (uneven speed) of the tape transport. Later videorecorders used a time base corrector to remove this jitter and make synchronization with the studio house sync. possible.

In order to cope with 625-line PAL or SECAM colour transmissions VERA would likely have required an even faster, and possibly unfeasible, tape speed.

Development began in 1952, but VERA was not perfected until 1958. It was given a live demonstration on-air in Panorama on April 14, 1958; Richard Dimbleby, seated by a clock, talked for a couple of minutes about the new method of vision recording with an instant playback, and then the tape was wound back and replayed. The picture was slightly watery, but reasonably watchable,[1] and instant playback was something completely new.

However, by this time it had already been rendered obsolete by the Ampex quadruplex video recording system. This used 5-centimetre (2.0 in) wide tapes running at a speed of 38 cm (15 in) per second. The rapid tape-to-head speed of quadruplex videotape was achieved by spinning the heads rapidly on a drum: the system used, with variations, on all video tape systems ever since, as well as DAT.

The BBC scrapped VERA and quickly adopted the Ampex system. It has been suggested that the BBC only continued to develop VERA as a bargaining tool, so it would be offered some of the first Ampex machines produced in unstated exchange for abandoning further work on a potential rival.

See also

Notes

  1. ^ Description from seeing the original transmission. Part of it can be seen on YouTube.

External links

This page was last edited on 10 September 2020, at 15:49
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