VHS
VHS is a discontinued standard for consumer-level analog video recording on tape cassettes, introduced in 1976 by JVC. It was the dominant home video format throughout the tape media period of the 1980s through the 1990s and into the early 2000s.
Magnetic tape video recording was adopted by the television industry in the 1950s in the form of the first commercialized video tape recorders, but the devices were expensive and used only in professional environments. In the 1970s, videotape technology became affordable for home use, and widespread adoption of videocassette recorders began; the VHS became the most popular media format for VCRs as it would win the "format war" against Betamax and a number of other competing tape standards.
The cassettes themselves use a 0.5-inch magnetic tape between two spools and typically offer a capacity of at least two hours. The popularity of VHS was intertwined with the rise of the video rental market, when films were released on pre-recorded videotapes for home viewing. Newer improved tape formats such as S-VHS were later developed, as well as the earliest optical disc format, LaserDisc; the lack of global adoption of these formats increased VHS's lifetime, which eventually peaked and started to decline in the late 1990s after the introduction of DVD, a digital optical disc format. VHS rentals were surpassed by DVD in the United States in 2003, which eventually became the preferred low-end method of movie distribution. For home recording purposes, VHS and VCRs were surpassed by digital video recorders in the 2000s. Production of all VHS equipment ceased by 2016, although the format has since gained some popularity amongst collectors.
History
Before VHS
In 1956, after several attempts by other companies, the first commercially successful VTR, the Ampex VRX-1000, was introduced by Ampex Corporation. At a price of US$50,000 in 1956 and US$300 for a 90-minute reel of tape, it was intended only for the professional market.Kenjiro Takayanagi, a television broadcasting pioneer then working for JVC as its vice president, saw the need for his company to produce VTRs for the Japanese market at a more affordable price. In 1959, JVC developed a two-head video tape recorder and, by 1960, a color version for professional broadcasting. In 1964, JVC released the DV220, which would be the company's standard VTR until the mid-1970s.
In 1969, JVC collaborated with Sony Corporation and Matsushita Electric to build a video recording standard for the Japanese consumer. The effort produced the U-matic format in 1971, which was the first cassette format to become a unified standard for different companies. It was preceded by the reel-to-reel " EIAJ format.
The U-matic format was successful in businesses and some broadcast television applications, such as electronic news-gathering, and was produced by all three companies until the late 1980s, but because of cost and limited recording time, very few of the machines were sold for home use. Therefore, soon after the U-Matic release, all three companies started working on new consumer-grade video recording formats of their own. Sony started working on Betamax, Matsushita started working on VX, and JVC released the CR-6060 in 1975, based on the U-matic format.
VHS development
In 1971, JVC engineers Yuma Shiraishi and Shizuo Takano put together a team to develop a VTR for consumers.By the end of 1971, they created an internal diagram, "VHS Development Matrix", which established twelve objectives for JVC's new VTR:
- The system must be compatible with any ordinary television set.
- Picture quality must be similar to a normal air broadcast.
- The tape must have at least a two-hour recording capacity.
- Tapes must be interchangeable between machines.
- The overall system should be versatile, meaning it can be scaled and expanded, such as connecting a video camera, or dubbing between two recorders.
- Recorders should be affordable, easy to operate, and have low maintenance costs.
- Recorders must be capable of being produced in high volume, their parts must be interchangeable, and they must be easy to service.
Competition with Betamax
In 1974, the Japanese Ministry of International Trade and Industry, desiring to avoid consumer confusion, attempted to force the Japanese video industry to standardize on just one home video recording format. Later, Sony had a functional prototype of the Betamax format, and was very close to releasing a finished product. With this prototype, Sony persuaded the MITI to adopt Betamax as the standard, and allow it to license the technology to other companies.JVC believed that an open standard, with the format shared among competitors without licensing the technology, was better for the consumer. To prevent the MITI from adopting Betamax, JVC worked to convince other companies, in particular Matsushita, to accept VHS, and thereby work against Sony and the MITI. Matsushita agreed, primarily out of concern that Sony might become the leader in the field if its proprietary Betamax format was the only one allowed to be manufactured. Matsushita also regarded Betamax's one-hour recording time limit as a disadvantage.
Matsushita's backing of JVC persuaded Hitachi, Mitsubishi, and Sharp to back the VHS standard as well. Sony's release of its Betamax unit to the Japanese market in 1975 placed further pressure on the MITI to side with the company. However, the collaboration of JVC and its partners was much stronger, which eventually led the MITI to drop its push for an industry standard. JVC released the first VHS machines in Japan in late 1976, and in the United States in mid-1977.
Sony's Betamax competed with VHS throughout the late 1970s and into the 1980s. Betamax's major advantages were its smaller cassette size, theoretical higher video quality, and earlier availability, but its shorter recording time proved to be a major shortcoming.
Originally, Beta I machines using the NTSC television standard were able to record one hour of programming at their standard tape speed of 1.5 inches per second . The first VHS machines could record for two hours, due to both a slightly slower tape speed and significantly longer tape. Betamax's smaller cassette limited the size of the reel of tape, and could not compete with VHS's two-hour capability by extending the tape length. Instead, Sony had to slow the tape down to 0.787 ips in order to achieve two hours of recording in the same cassette size. Sony eventually created a Beta III speed of 0.524 ips, which allowed NTSC Betamax to break the two-hour limit, but by then VHS had already won the format battle.
Additionally, VHS had a "far less complex tape transport mechanism" than Betamax, and VHS machines were faster at rewinding and fast-forwarding than their Sony counterparts.
VHS eventually won the war, gaining 60% of the North American market by 1980.
Initial releases of VHS-based devices
The first VCR to use VHS was the Victor HR-3300, and was introduced by the president of JVC in Japan on September 9, 1976. JVC started selling the HR-3300 in Akihabara, Tokyo, Japan, on October 31, 1976. Region-specific versions of the JVC HR-3300 were also distributed later on, such as the HR-3300U in the United States, and the HR-3300EK in the United Kingdom. The United States received its first VHS-based VCR, the RCA VBT200, on August 23, 1977. The RCA unit was designed by Matsushita and was the first VHS-based VCR manufactured by a company other than JVC. It was also capable of recording four hours in LP mode. The UK received its first VHS-based VCR, the Victor HR-3300EK, in 1978.Quasar and General Electric followed-up with VHS-based VCRs – all designed by Matsushita. By 1999, Matsushita alone produced just over half of all Japanese VCRs. TV/VCR combos, combining a TV set with a VHS mechanism, were also once available for purchase. Combo units containing both a VHS mechanism and a DVD player were introduced in the late 1990s, and at least one combo unit, the Panasonic DMP-BD70V, included a Blu-ray player.
Technical details
VHS has been standardized in IEC 60774–1.Cassette and tape design
The VHS cassette is a 187 mm wide, 103 mm deep, and 25 mm thick plastic shell held together with five Phillips-head screws. The flip-up cover, which allows players and recorders to access the tape, has a latch on the right side, with a push-in toggle to release it. The cassette has an anti-despooling mechanism, consisting of several plastic parts between the spools, near the front of the cassette. The spool latches are released by a push-in lever within a 6.35 mm hole at the bottom of the cassette, 19 mm in from the edge label. The tapes are made, pre-recorded, and inserted into the cassettes in cleanrooms, to ensure quality and to keep dust from getting embedded in the tape and interfering with recordingThere is a clear tape leader at both ends of the tape to provide an optical auto-stop for the VCR transport mechanism. In the VCR, a light source is inserted into the cassette through the circular hole in the center of the underside, and two photodiodes are on the left and right sides of where the tape exits the cassette. When the clear tape reaches one of these, enough light will pass through the tape to the photodiode to trigger the stop function; some VCRs automatically rewind the tape when the trailing end is detected. Early VCRs used an incandescent bulb as the light source: when the bulb failed, the VCR would act as if a tape were present when the machine was empty, or would detect the blown bulb and completely stop functioning. Later designs use an infrared LED, which has a much longer life.
The recording medium is a Mylar magnetic tape, 12.7 mm wide, coated with metal oxide, and wound on two spools. VHS tapes stored next to magnetic materials can become damaged or distorted due to the disruption of the oxide particles.
The tape speed for "Standard Play" mode is 3.335 cm/s for NTSC, 2.339 cm/s for PAL—or just over 2.0 and 1.4 metres per minute respectively. The tape length for a T-120 VHS cassette is 247.5 metres.