VHS

The Video Home System, better known by its abbreviation VHS, is a recording and playing standard for analog video cassette recorders (VCRs), developed by Victor Company of Japan, Limited, aka JVC, and launched in September 1976. more...

Home
Amplifiers
Audio Accessories & Cables
Cable TV
DVD Players & Recorders
Digital Video Recorders, PVR
Gadgets & Other Electronics
Home Audio
Home Theater Projectors
Home Theater in a Box
Radios: CB, Ham & Shortwave
Satellite Radio
Satellite TV
Telephones & Pagers
Televisions
VCRs
Beta
VHS
Standard
Other Brands
Panasonic
Philips, Magnavox
Stereo, Hi-Fi
JVC
Other Brands
Panasonic
Sony
Vintage Electronics

By the 1990s, VHS became a standard format for consumer recording and viewing, after competing in a fierce format war with Sony Corporation's Betamax and, to a lesser extent, Philips' Video 2000. VHS initially offered a longer playing time than the Betamax system, and it also had the advantage of a far less complex tape transport mechanism. Although VHS and Betamax were competing formats, several of VHS' critical technology are licensed from Sony. Early VHS machines could rewind and fast forward the tape considerably faster than a Betamax VCR since they unthreaded the tape from the playback heads before commencing any high-speed winding. Most newer VHS machines do not perform this unthreading step, as head-tape contact is no longer an impediment to fast winding, due to improved engineering.

The week of 15 June 2003 marked the first time the DVD format (which was launched in the late 1990s) became more popular than VHS in the USA. Although still popular for home recording, the VHS tape has largely been replaced by DVD for pre-recorded home video content.

As of July 2006, most major film studios have stopped releasing new movie titles in VHS format, opting for DVD-only releases. VHS prerecorded cassettes, however, are still popular with many collectors, mainly because there are thousands of titles that are still unavailable on DVD or other newer formats.

Technical details

A VHS cassette contains a ½ inch (12.7 mm) wide magnetic tape wound between two spools, allowing it to be slowly passed over the various playback and recording heads of the video cassette recorder. The tape speed is 3.335 cm/s for NTSC, 2.339 cm/s for PAL. A cassette holds a maximum of about 430 m of tape at the lowest acceptable tape thickness, giving a maximum playing time of about 3.5 hours for NTSC and 5 hours for PAL at "standard" (SP) quality. Most cassettes have lower recording times because they use thicker tape, which helps avoid jams; careful users generally avoid the thinnest tapes. More recent machines usually allow the selection of longer recording times by lowering the tape speed: LP mode (for PAL and some NTSC machines) halves the tape speed and doubles the recording time, while EP mode (for NTSC and some newer PAL machines, aka SLP mode) drops the tape speed to one-third, for triple the recording time. Of course, these speed reductions cause corresponding reductions in video quality; also, tapes recorded at the lower speed often exhibit poor playback performance on recorders other than the one they were produced on. Because of this, commercial prerecorded tapes were almost always recorded in SP mode. The only exceptions were "discount" tapes, usually containing children's cartoons or older shows, usually recorded at SLP speed but sometimes including Hi-Fi audio to help enhance sound quality. An unofficial LP mode with half the standard speed exists on some NTSC machines, but is not part of the VHS standard.

Read more at Wikipedia.org