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Videocassette recorder

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A VHS VCR manufactured by Metz
The inside of a VCR
Not all video tape recorders use a cassette to contain the magnetic recording video tape. Early models of consumer video tape recorders VTRs, and most professional broadcast analog videotape machines (e.g. 1-inch Type C) use reel to reel tape spools that require hand-threading of the tape. (This is the first portable video recorder, the 1967 Ampex quadruplex.) Reel-to-reel VTRs quickly vanished from the consumer market, but were standard in the broadcast industry as long as analog tape was.

The videocassette recorder (or VCR, also known as the video recorder), is a type of electro-mechanical device that uses removable videocassettes that contain magnetic tape for recording analog audio and analog video from broadcast television so that the images and sound can be played back at a more convenient time. This facility afforded by a VCR machine is commonly referred to as television program Timeshifting. Most domestic VCRs are equipped with a television broadcast receiver (tuner) for TV reception, and a programmable clock (timer) for unattended recording of a certain television channel at a particular time. These features began as simple mechanical counter-based single event timers, but were later replaced by multiple event digital clock timers that afforded greater flexibility to the user. In later models the multiple timer events could be programmed through a menu interface that was displayed on the playback TV screen. This allowed multiple programs to be recorded easily, and this particular feature of the video recorder quickly became a major selling point and benefit to people working unsociable hours who usually missed many television broadcasts.

A VCR operates in a different way from a video tape recorder. VTRs originated as individual tape reels, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. VTRs are reel-to-reel devices that require hand-threading of the tape from a single supply reel, through the recording mechanism and onto a separate take-up reel. VCRs tend to be lower maintenance than reel-to-reel VTRs, since the tape path is usually fully enclosed to keep dust out of the mechanism, and the tape is almost never touched by the user except when malfunctions occur.[disputed ]

Contents

History

Early machines and formats

The history of the videocassette recorder follows the history of videotape recording in general. In 1952 the Vision Electronic Recording Apparatus high speed multi-track machine was built and trialed by the BBC.[1] This machine used a thin steel tape on a 21 inch (53.5 cm) reel travelling at over 200 inches (510 cm) per second. Despite 6 years of research and improvements the machine became obsolete when Ampex introduced the Ampex VRX-1000. This model became the world's first commercially successful videotape recorder in 1956. It used the 2" Quadruplex format, using two-inch (5.1 cm) tape.[2] Due to its US$50,000 price, the Ampex VRX-1000 could be afforded only by the television networks and the largest individual stations.[3]

In 1963, Philips introduced their EL3400 1" helical scan recorder (aimed at the business and domestic user) and Sony marketed the 2" PV-100, their first reel-to-reel VTR intended for business, medical, airline, and educational use.[4]

First home video recorders

The Telcan, produced by the Nottingham Electronic Valve Company in 1963, was the first home video recorder. It could be bought as a unit or in kit form for £60. However, there were several drawbacks: it was expensive, not easy to put together and could only record 20 minutes output at a time in black-and-white.[5][6][7]

The Sony model CV-2000, first marketed in 1965, was their first VTR intended for home use and was based on half inch tape.[8] Ampex and RCA followed in 1965 with their own reel-to-reel monochrome VTRs priced under US $1,000 for the home consumer market.

The EIAJ format was a standard half-inch format used by various manufacturers. EIAJ-1 was an open reel format. EIAJ-2 used a cartridge that contained a supply reel, but not the take-up reel. As the take-up reel was part of the recorder, the tape had to be fully rewound before removing the cartridge, a slow procedure.

The development of the videocassette followed the replacement by cassette of other open reel systems in consumer items: the Stereo-Pak 4-track audio cartridge in 1962, the compact audio cassette and Instamatic film cartridge in 1963, the 8-track cartridge in 1965, and the Super 8 home movie cartridge in 1966.

Sony U-matic

Sony demonstrated a videocassette prototype in October 1969, then set it aside to work out an industry standard by March 1970 with seven fellow manufacturers. The result, the Sony U-matic system, introduced in Tokyo in September 1971, was the world's first commercial videocassette format. Its cartridges, resembling larger versions of the later VHS cassettes, used 3/4-inch (1.9 cm) tape and had a maximum playing time of 60 minutes, later extended to 90 minutes. Sony also introduced two machines (the VP-1100 videocassette player and the VO-1700 videocassette recorder) to use the new tapes. U-matic, with its ease of use, quickly made other consumer videotape systems obsolete in Japan and North America, where U-matic VCRs were widely used by television newsrooms, schools and businesses. But the cost—US$1,395 for a combination TV/VCR, or $7,069 in 2007 dollars—kept it out of most homes.[9]

Philips "VCR" format

An N1500 video recorder, with wooden cabinet.

In 1970 Philips developed a home videocassette format. Confusingly, Philips named this format "VCR" (although it is also referred to as "N1500", after the first recorder's model number). The format was also supported by Grundig and Loewe. It used square cassettes and half-inch (1.3 cm) tape, mounted on co-axial reels, giving a recording time of one hour. The first model, available in the United Kingdom in 1972, was equipped with a crude timer that used rotary dials. At nearly £600 ($2087), it was expensive and the format was relatively unsuccessful in the home market. This was followed by digital timer version in 1975, the N1502. In 1977 a new (and incompatible) long-play version ("VCR-LP") or N1700, which could use the same tapes, sold quite well to schools and colleges.

Avco Cartrivision

The Avco Cartrivision system, a combination television set and VCR from Cartridge Television Inc. that sold for US $1,350, was the first videocassette recorder to have pre-recorded tapes of popular movies available for rent. Like Philips' VCR format, the square Cartrivision cassette had the two reels of half-inch tape mounted on top of each other, but it could record up to 114 minutes. It did so using a crude form of video compression that recorded only every third video field and played it back three times. Cassettes of major movies such as The Bridge on the River Kwai and Guess Who's Coming to Dinner were ordered via catalog at a retailer, delivered by parcel mail, and then returned to the retailer after viewing. Other cassettes on sports, travel, art, and how-to topics were available for purchase. An optional monochrome camera could be bought to make home videos. Cartrivision was first sold in June 1972, mainly through Sears, Macy's, and Montgomery Ward department stores in the United States. It was abandoned thirteen months later after poor sales.

The late 1970s: mass-market success

It was not until the late 1970s, when European and Japanese companies developed more technically advanced machines with more accurate electronic timers and greater tape duration, that the VCR started to become a mass market consumer product. By 1979 there were three competing technical standards, with different, physically incompatible tape cassettes.

VHS vs. Betamax

A Betamax cassette

The two major standards were Sony's Betamax (also known as Betacord or just Beta), and JVC's VHS [Video Home System], which competed for sales in what became known as the format war.

Betamax was first to market in November 1975, and was argued by many to be technically more sophisticated in recording quality,[10] although many users did not perceive a visual difference. The first machines required an external timer, and could only record one hour. The timer was later incorporated within the machine as a standard feature.

The rival VHS format, introduced in Japan by JVC in September 1976 (and introduced in the United States in July 1977 by RCA) boasted a longer two-hour recording time with a T-120 tape, with four hours using a "long play" mode (RCA SelectaVision models, introduced in September 1977).

In 1978 the majority of consumers in the U.K. chose to rent rather than purchase this new expensive home entertainment technology. JVC introduced the HR3300 model[11] with E-30, E-60, E-120, E-180 minute cassette tapes with up to three hours recording time, a thinner 4 hour length E240 tape soon followed.

The rental market was a contributing factor for acceptance of the VHS home system. 2 hours and 4 hours recording times were considered ideal for recording movies and sports-games. Although Sony later introduced L-500 (2 hour) and L-750 (3 hour) tapes in addition to the L-250 (1 hour) tape the consumer market had swiftly moved toward the VHS system as a preferred choice. During the 80s dual speed (long play) models of both BETA and VHS recorders were introduced allowing for much longer recording times.

Philips V2000 format video cassette recorder

Philips Video 2000

A third format, Video 2000, or V2000 (also marketed as "Video Compact Cassette") was developed and introduced by Philips in 1978, and was sold only in Europe. Grundig developed and marketed their own models based on the V2000 format. Most V2000 models featured piezoelectric head positioning to dynamically adjust the tape tracking. V2000 cassettes had two sides, and like the audio cassette had to be flipped over halfway through their recording time. User switchable record protect levers were used instead of the breakable lugs found on VHS/Beta cassettes. The half-inch tape used contained two parallel quarter-inch tracks, one for each side. It had a recording time of 4 hours per side, later extended to 8 hours per side on a few models. V2000 hit the market after its two rivals in early 1979. The last models produced by Philips in 1985 were felt by many to be superior machines to anything else on the market at the time but the poor reputation gained through the limited features and poor reliability of early models, and the by now dominant market share of VHS/Betamax, ensured only limited sales before the system was scrapped shortly after.

Other early formats

Some less successful consumer videocassette formats include:

Legal challenges

In the early 1980s, the film companies in the US fought to suppress the device in the consumer market, citing concerns about copyright violations. In Congressional hearings, Motion Picture Association of America head Jack Valenti decried the "savagery and the ravages of this machine" and likened its effect on the film industry and the American public to the Boston strangler:

We are going to bleed and bleed and hemorrhage, unless this Congress at least protects one industry that is able to retrieve a surplus balance of trade and whose total future depends on its protection from the savagery and the ravages of this machine. ... I say to you that the VCR is to the American film producer and the American public as the Boston strangler is to the woman home alone.
—Hearings before the Subcommittee on Courts, Civil Liberties and the Administration of Justice of the Committee of the Judiciary, House of Representatives, Ninety-seventh Congress, Second Session on H.R. 4783, H.R. 4794 H.R. 4808, H.R. 5250, H.R. 5488, and H.R. 5705, Serial No 97, Part I, Home Recording of Copyrighted Works, April 12, 1982. US Government Printing Office.[12]

In the case Sony Corp. of America v. Universal City Studios, Inc., the Supreme Court of the United States ruled that the device was allowable for private use, thereby guaranteeing market acceptance. In the years following, the film companies found that selling professionally-produced video recordings of their products had become a major income source.

Product flaws

The video cassette recorder is known to have glitches and common bugs. The most common problem was temperature and humidity changes, if the machine (or tape) was moved from a cold to a hotter environment condensation would occur on the internal parts, such as the rotating video head drum. Most models were later equipped with a Dew warning indicator which was intended to prohibit operation. This device however could not detect moisture on the surface of any cold tape inserted. Users often experienced the magnetic tape to be 'chewed' or 'eaten' when ejected from the machine due to this moisture. Other causes of malfunction occurred when the rubber drive belts or rubber rollers hardened with age.[13] Faults such as these rendered the tape unusable, and if valuable footage (such as a wedding) was involved this loss could be traumatic for users. VHS tapes recorded in LP or EP/SLP mode tend to not play back very well on other machines due to record / replay head alignment tolerances, and tapes recorded on a machine made before 1995 tend to not play well on newer machines due to slight changes in helical scanning head technology design. Most machines no longer have control switches linked to mechanical parts, but rely on solenoids and motor driven mechanisms to perform changes of function.

Decline

A typical VCR toward the end of its popularity. After decades of refinement in design and production, models similar to this were available for under US$50

In the early 2000s, DVD gradually overtook VHS as the most popular consumer format for playback of prerecorded video. DVD recorders and other digital video recorders such as TiVo have recently begun to drop in price in developed countries, which some consider to be the end for VCRs in those markets. DVD rentals in the United States first exceeded those of VHS in June 2003, and in 2005 the president of the Video Software Dealers Association predicted that 2006 would be the last year for major releases on VHS.[14] Most consumer electronics retailers in North America (such as Best Buy) carry only a few VCRs (often VCR/DVD-recorder hybrids). Due to economies of scale and simpler construction, DVD players became cheaper than VCRs.[citation needed]

Because of lack of sales, most manufacturers slowly reduced their VCR lineups to only basic consumer models (phasing out professional models and S-VHS models) or stopped production completely.[citation needed] The models that were produced often lacked features considered standard in an earlier era, such as front panel controls or a built-in digital clock.

The declining market combined with a Federal Communications Commission mandate effective March 1, 2007, that all new TV tuners be ATSC tuners have encouraged major electronics makers, including Funai, JVC, and Panasonic, to end production of standalone units for the US market. To avoid this costly mandate, most new standalone VCRs in the US today can only record from external baseband sources (usually composite video), including CECBs which (by NTIA mandate) all have composite outputs, as well as those ATSC tuners (including TVs) & cable boxes that come with composite outputs.

The new high definition optical disc format Blu-ray Disc may gradually replace the DVD format. Some analysts[who?] expect this change to take place like the VHS to DVD transition. However, with many homes still having a large supply of VHS tapes and with all Blu-ray players designed to play regular DVDs and CDs by default, some manufacturers are now making VCR/Blu-ray combo players.[15] Also, Blu-ray may be a short-lived format, as streaming video over the internet to a set top box like the Roku or a game console like the Nintendo Wii may replace physical media entirely.

Special features

Multi standard

One of the problems faced with the use of video recorders was especially the exchange of recordings between PAL and NTSC countries. Multi Standard video recorders and TV sets gradually overcame these incompatibility problems.[citation needed]

Stereo Sound and HiFi

The U-matic machines were always made with Stereo, and Beta and VHS started out splitting the audio track on the tape, but the slow tape speed of Beta and VHS limited the sound quality. This led to the introduction of HiFi, whose left and right sound tracks were modulated as FM on the video portion of the tape. The 8 mm format always used the video portion of the tape for sound, with an FM carrier between the band space of the chrominance and luminance on the tape. 8 mm could be upgraded to Stereo, by adding an extra FM signal for Stereo difference.[citation needed]

Copy protection

Introduced in 1983, Macrovision is a system that reduces the quality of recordings made from commercial video tapes, DVDs and pay-per-view broadcasts by adding random peaks of luminance to the video signal during vertical blanking. These confuse the automatic level adjustment of the recording VCR which causes the brightness of the picture to constantly change, rendering the recording unwatchable.

When creating a copy-protected videocassette, the Macrovision-distorted signal is stored on the tape itself by special recording equipment. By contrast, on DVDs there is just a marker asking the player to produce such a distortion during playback. All standard DVD players include this protection and obey the marker, though unofficially many models can be modified or adjusted to disable it.

Also, the Macrovision protection system may fail to work on older VCR's made before 1986 and some high end decks built afterwords, usually due to the lack of an AGC system. Newer VHS and S-VHS machines (and DVD recorders) are susceptible to this signal; generally, machines of other tape formats are unaffected, such as all 3 Betamax variants. VCRs designated for "professional" usage typically have an adjustable AGC system, a specific "Macrovision removing" circuit, or Time Base Corrector (TBC) and can thus copy protected tapes with or without preserving the protection. Such VCRs are usually overpriced and sold exclusively to certified professionals (linear editing using the 9-Pin Protocol, TV stations etc.) via controlled distribution channels in order to prevent their being used by the general public (however, said professional VCRs can be purchased reasonably by consumers on the second-hand/used market, depending on the VCR's condition). Nowadays, most DVDs still have copyright protection, but certain DVDs do not have it, usually pornography and bootlegs. However, some DVDs, such as certain DVD sets, do not have the protection against VHS copying, possibly due to the VHS format no longer used as a major retail medium for home video.

Flying erase heads

The flying erase head is a feature that may be found in some high end home VCRs as well as some broadcast grade VCRs to cleanly edit the video.

Normally, the tape is passed longitudinally through two fixed erase heads, one located just before the tape moves to the video head drum and the other right next to the audio/control head stack. Upon recording, the erase heads erases any old recording contained on the tape to prevent anything already recorded on it from interfering with what is being recorded.

However, when trying to edit footage deck to deck, portions of the old recording's video may be between the erase head and video recording heads. This results in a faint rainbow-like noise at and briefly after the point of the cut as the old video recording missed by the fixed erase head is never completely erased as the new recording is printed.

The flying erase head is so-called because an erase head is mounted on the video head drum and rotates around in the same manner as the video heads. In the record mode, the erase head is active and erases the video precisely down to the recorded video fields. The flying erase head runs over the tape and the video heads record the signal virtually instantly after the flying erase head has passed.

Since the erase head erases the old signal right before the video heads write onto the tape, there is no remnants of the old signal to cause visible distortion at and after the moment a cut is made, resulting in a clean edit. In addition, the ability of flying erase heads to erase old video off the tape right before recording new video on it allows the ability to perform insert editing, where new footage can be placed within an existing recording with clean cuts at the beginning and end of the edit.

Variants

In addition to the standard home VCR, a number of variants have been produced over the years. These include combined "all-in-one" devices such as the televideo (a TV and VCR in one unit) and DVD/VCR units and even TV/VCR/DVD all-in-one units.

Dual-deck VCRs (marketed as "double-decker") have also been sold, albeit with less success.

Camcorders also feature an integrated VCR. Most of these use smaller format videocassettes, such as 8 mm, VHS-C, or MiniDV, although some early models supported full-size VHS and Betamax. Generally, they include neither a timer nor a TV tuner.

See also

References

  1. ^ "The History of Magnetic Recording". BBC 20 December 2004. http://www.bbc.co.uk/dna/h2g2/A3224936. Retrieved 15 March 2011. 
  2. ^ "Ampex VRX-1000 - The First Commercial Videotape Recorder in 1956". Cedmagic.com. 1956-04-14. http://www.cedmagic.com/history/ampex-commercial-vtr-1956.html. Retrieved 2010-05-31. 
  3. ^ Richard N. Diehl. "Labguy'S World: The Birth Of Video Recording". Labguysworld.com. http://www.labguysworld.com/VTR_BirthOf.htm. Retrieved 2010-05-31. 
  4. ^ "Sony Global - Sony History". Sony.net. http://www.sony.net/Fun/SH/1-11/h1.html. Retrieved 2010-05-31. [dead link]
  5. ^ "The quest for home video: Telcan home video recorder". Terramedia.co.uk. 2001-10-22. http://www.terramedia.co.uk/media/video/telcan.htm. Retrieved 2010-05-31. 
  6. ^ "Total Rewind". Total Rewind. http://www.totalrewind.org/revolution/R_telwes.htm. Retrieved 2010-05-31. 
  7. ^ "BBC History". Bbc.co.uk. 1963-06-24. http://www.bbc.co.uk/ahistoryoftheworld/objects/aNhfBgCgSByEMns5XPxXqA. Retrieved 2010-05-31. 
  8. ^ "Sony CV Series Video". Smecc.org. http://www.smecc.org/sony_cv_series_video.htm. Retrieved 2010-05-31. 
  9. ^ Sony sold 15,000 U-matic machines in the U.S. in its first year. "Television on a Disk," Time, September 18, 1972.
  10. ^ "Why is Beta better". Web.archive.org. 2007-06-08. Archived from the original on 2007-06-08. http://web.archive.org/web/20070608042149/http://www.betainfoguide.com/BetaBetter.html. Retrieved 2010-05-31. 
  11. ^ "JVC HR3300". Rewind museum company 2010. http://www.totalrewind.org/vhs/H_3300.htm. Retrieved 16 March 2011. 
  12. ^ "Jack Valenti Testimony at 1982 House Hearing on Home Recording of Copyrighted Works". Cryptome.org. http://cryptome.org/hrcw-hear.htm. Retrieved 2010-05-31. 
  13. ^ "VCR eats tapes". The Sci.Electronics.Repair (S.E.R) FAQ. http://www.repairfaq.org/REPAIR/F_vcrfaq4.html#VCRFAQ_001. Retrieved 16 March 2011. 
  14. ^ Jen Chaney, "Parting Words For VHS Tapes, Soon to Be Gone With the Rewind," The Washington Post, August 28, 2005; p. N01.
  15. ^ http://www.amazon.com/Panasonic-DMP-BD70V-Blu-ray-Multimedia-Player/dp/B001VZ1W5U/ref=sr_1_1?ie=UTF8&s=electronics&qid=1277226480&sr=8-1

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