Video Cassette Recording

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This article is about the VCR ('Video Cassette Recording') videocassette format from Philips. This should not be confused with the later (and incompatible) VCC format ('Video Compact Cassette', more commonly known as Video 2000). For the generic article covering all videocassette recorders (VCRs), see Videocassette recorder.


Video Cassette Recording (VCR) was an early domestic video format designed by Philips. It was the first successful home videocassette recorder system. Later variants included the VCR-LP and Super Video (SVR) formats.

The VCR format was introduced in 1972, just after the Sony U-matic format in 1971. Although at first glance the two might appear to have been competing formats, they were aimed at very different markets. U-matic was introduced as a professional format, whilst VCR was targeted particularly at educational but also domestic users.

Home video systems had previously been available, but they were open reel systems (most notably made by Sony) and were expensive to both buy and operate. They were also unreliable and often only recorded in black and white. The VCR system was easy to use and recorded in colour but was still expensive: the N1500 recorder cost nearly £600 in the United Kingdom when it was introduced in 1972, the equivalent of more than £4500 today.

An N1500 video recorder, with wooden cabinet.
An N1500 video recorder, with wooden cabinet.

The VCR format used large square cassettes with 2 co-axial reels, one on top of the other, containing half inch wide chrome dioxide magnetic tape. Three playing times were available: 30, 45 and 60 minutes. The 60-minute cassettes proved very unreliable, suffering numerous snags and breakages due to the very thin tape. The mechanically complicated recorders themselves also proved somewhat unreliable. One particularly common failing occurred should tape slack develop within the cassette; the tape from the top (takeup) spool may droop into the path of the bottom (supply) spool and become entangled in it if rewind was selected. The cassette would then completely jam and require dismantling to clear the problem, and the tape would then be creased and damaged.

The system predated the development of the slant azimuth technique to prevent crosstalk between adjacent video tracks, so it had to use an unrecorded guard band between tracks. This required the system to run at a high tape speed of around 11.5 inches per second.

Despite its limitations, the Philips VCR system was groundbreaking and brought together many advances in video recording technology to produce the first truly practical home video cassette system.

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[edit] Variants

The rare Grundig SVR format machine.
The rare Grundig SVR format machine.

VCR later evolved into a related format known as VCR-LP. This exploited slant azimuth to greatly increase the recording time. Although both formats used identical VCR cassettes, the recordings were incompatible between the two systems, and no dual-format recorders ever existed. Philips N1700, released in 1977, supported the VCR-LP format.

A later even longer-playing variant, Super Video (SVR) was manufactured by Grundig exclusively. SVR was designed to exclusively use BASF and Agfa -manufactured chrome-dioxide tape in cassettes that were identical to the earlier Philips ones, with the exception of a small actuator added to the bottom of the cassette. This meant that only the BASF/Agfa tapes would work in SVR machines, but that such tapes could also be used in the older VCR and VCR-LP machines. Just as VCR-LP recordings are incompatible with VCR, so SVR recordings are incompatible with both VCR and VCR-LP. The only model to be built was the Grundig SVR4004, with a few detail variations including optional audio/video inputs and outputs.

[edit] Model Numbers

The First Philips machine was model number N1500, after which the format is also known. This had "first generation" mechanics including magnetic braking servo systems applied to relatively large mains voltage induction motors. The later model N1502 had a totally different mechanism using DC motors and more advanced electronics, and was somewhat more reliable. A later version again was still called N1502 but had further significant mechanical and electronic advances, and can be easily identified by having figure-8 mains power socket rather than a captive power cable. The N1512 model offered composite video input and output connectors, but was otherwise the same as the N1502. The VCR-LP model N1700 was closely related to the later N1502 variant.

[edit] Replacement

In the late 1970s, the VCR formats were superseded altogether by Video 2000 (also known as 'Video Compact Cassette' or VCC). Due to the similar initialisms, and the fact that both were designed by Philips, the 'VCC' and 'VCR' formats are often confused. However, the two systems are incompatible, and there are significant differences between them. Some Video 2000 machines carry a modified version of the "VCR" logo, as N1500 and N1700 machines, adding further to this confusion.

[edit] External links