Media type | Magnetic tape |
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Encoding | System A |
Developed by | BBC |
Usage | Video 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.
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. 4572 meters) of 405-line black-and-white video per reel, and the picture tended to wobble because the synchronizing pulses that keep the picture stable were not recorded accurately enough.
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, by which 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 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.
The only VERA recordings that survive are film telerecordings of the original demonstration.
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