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Helical Scan
Helical scan is a method of recording high-frequency signals on magnetic tape. It is used in open-reel video tape recorders, video cassette recorders, digital audio tape recorders, and some computer tape drives. History Earl E Masterson from RCA patented the first helical scan method in 1950 after stealing it from German engineer Eduard Schüller. Eduard Schüller developed an actually working helical scan method of recording in 1953 while working at AEG. With the advent of television broadcasting in Japan in the early 1950s, they saw the need for magnetic television signal recording. Dr. Kenichi Sawazaki developed a prototype helical scan recorder in 1954. Gallery Bcn-scanner-head.jpg, Type B videotape video scanner head Vxa1-drive-nocover-nobezel-front.jpg, rotary head visible in a VXA computer tape drive Vxa1-drive-nocover-top-front.jpg, VXA tape drive, alternate view of rotary head and loading mechanism See also * Type A videotape * 1 inch type B videotape * 1 i ...
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Helical Tape Drive
Helical may refer to: * Helix, the mathematical concept for the shape * Helical engine, a proposed spacecraft propulsion drive * Helical spring, a coilspring * Helical plc, a British property company, once a maker of steel bar stock * Helicoil A threaded insert, also known as a threaded bushing, is a fastener element that is inserted into an object to add a threaded hole. They may be used to repair a stripped threaded hole, provide a durable threaded hole in a soft material, place a thr ..., a mechanical thread repairing insert * H-el-ical//, stage name for Hikaru, Japanese singer {{disambig ...
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1 Inch Type B Videotape
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest positive integer. It is also sometimes considered the first of the infinite sequence of natural numbers, followed by  2, although by other definitions 1 is the second natural number, following  0. The fundamental mathematical property of 1 is to be a multiplicative identity, meaning that any number multiplied by 1 equals the same number. Most if not all properties of 1 can be deduced from this. In advanced mathematics, a multiplicative identity is often denoted 1, even if it is not a number. 1 is by convention not considered a prime number; this was not universally accepted until the mid-20th century. Additionally, 1 is ...
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Film And Video Technology
A film also called a movie, motion picture, moving picture, picture, photoplay or (slang) flick is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, feelings, beauty, or atmosphere through the use of moving images. These images are generally accompanied by sound and, more rarely, other sensory stimulations. The word "cinema", short for cinematography, is often used to refer to filmmaking and the film industry, and to the art form that is the result of it. Recording and transmission of film The moving images of a film are created by photographing actual scenes with a motion-picture camera, by photographing drawings or miniature models using traditional animation techniques, by means of CGI and computer animation, or by a combination of some or all of these techniques, and other visual effects. Before the introduction of digital production, series of still images were recorded on a strip of chemically sensitize ...
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Audiovisual Introductions In 1953
Audiovisual (AV) is electronic media possessing both a sound and a visual component, such as slide-tape presentations, films, television programs, corporate conferencing, church services, and live theater productions. Audiovisual service providers frequently offer web streaming, video conferencing, and live broadcast services. Computer-based audiovisual equipment is often used in education, with many schools and universities installing projection equipment and using interactive whiteboard technology. Components Aside from equipment installation, two significant elements of audiovisual are wiring and system control. If either of these components are faulty or missing, the system may not demonstrate optimal performance. Wiring is a skill that not only requires proper cable rating selection based on a number of factors, including distance to the main rack, frequency and fire codes, but wires should also be out of sight, behind the walls and in the ceiling, when possible. Sys ...
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Experimental Television Center
The Experimental Television Center (ETC) (1969–2011) was a nonprofit electronic and media art center located in upstate New York. History The Experimental Television Center (ETC) was founded in 1971 by Ralph Hocking. The center was the result of the expansion of a media access program that Ralph Hocking established as professor of video and computer art at Binghamton University in 1969. Some years later, in July 1979, the center was moved from Binghamton to Owego, New York. The ETC, directed by Ralph Hocking and Sherry Miller Hocking, was devoted to the exploration and development of potential uses of new technology in video and media art. Artists, social, cultural and educational organizations and also interested individuals worked in innovative image processing tools, using all the equipment and the studio facilities with no charge. The Center for more than 40 years had provided a residency program that emphasized the aesthetic experimentation of electronic and media art th ...
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Symmetric Phase Recording
Symmetric Phase Recording is a tape recording (Computer storage media) technology developed by Quantum Corporation packs data across a tape's recording surface by writing adjacent tracks in a herringbone pattern: track 0 = \\\\\, track 1 = /////, track 2 = \\\\\, track 3 = /////, etc. This eliminates crosstrack interference and guard bands so that more tracks of data can be stored on a tape. References Further reading * * See also *Azimuth recording, Slant Azimuth recording *Digital Equipment Corporation *Digital Linear Tape *Linear Tape-Open *Digital Tape Format *Helical scan *Magnetic tape *Magnetic tape data storage Magnetic-tape data storage is a system for storing digital information on magnetic tape using digital recording. Tape was an important medium for primary data storage in early computers, typically using large open reels of IBM 7 track, 7-track, ... * Storage Technology Corporation Storage media {{Compu-hardware-stub ...
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Ampex 2 Inch Helical VTR
From 1963 to 1970, Ampex manufactured several models of VTR 2-inch helical VTRs, capable of recording and playing back analog black and white video. Recording employed non-segmented helical scanning, with one wrap of the tape around the video head drum being a little more than 180 degrees, using two video heads. One video drum rotation time was two fields of video. The units had two audio tracks recorded on the top edge of the tape, with a control track recorded on the tape's bottom edge. The 2-inch-wide video tape used was one mil (0.001 in or 0.0254 mm) thick. The VTRs were mostly used by industrial companies, educational institutions, and a few for in-flight entertainment. The capstan tape speed is 3.7 inches per second, which provided a long record time of up to five hours on large reels. The units were 100% solid state. The Ampex 2-inch helical VTRs were popular, as they were priced much less than the 2-inch quadruplex videotape recorders used in the broadcast ...
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Vision Electronic Recording Apparatus
Vision Electronic Recording Apparatus (VERA) was an early analog recording videotape format developed from 1952 by the BBC under project manager Dr Peter Axon. History 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 reels of magnetic tape that passed static heads at a speed of . VERA was capable of recording about 15 minutes (e.g. 4,572 meters) of 405-line black-and-white video per reel, and the picture tended to wobble because of some jitter (uneven speed) of the tape transport. Later video recorders used a time base corrector to remove this jitter and make synchronization with the studio house possible. In order to cope with 625-line PAL or SECAM colour transm ...
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Video Tape Recorder
A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material from magnetic tape. The early VTRs were open-reel devices that record on individual reels of 2-inch-wide (5.08 cm) tape. They were used in television studios, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. Beginning in 1963, videotape machines made instant replay during televised sporting events possible. Improved formats, in which the tape was contained inside a videocassette, were introduced around 1969; the machines which play them are called videocassette recorders. An agreement by Japanese manufacturers on a common standard recording format, which allowed cassettes recorded on one manufacturer's machine to play on another's, made a consumer market possible; and the first consumer videocassette recorder, which used the U-matic format, was introduced by Sony in 1971. History In early 195 ...
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IVC Videotape Format
IVC 2 inch Helical scan was a high-end broadcast quality helical scan analog recording VTR format developed by International Video Corporation (IVC), and introduced in 1975. Previously, IVC had made a number of 1 inch Helical VTRs. IVC saw a chance to make a VTR that would have the quality of the then-standard 2 inch Quadruplex videotape format but with the advantages of helical scan. They then developed a VTR using this technology, the IVC Model 9000. Versions *IVC made the Model 9000 in five versions: **IVC 9000 (NTSC and PAL unit, could record for 2 hours on one 10.5 inch reel) **IVC 9000-4 (4 ips tape speed, Long Play, could record and play back 4 hours on one 10.5 inch reel **IVC 9000-W (8 MHz record and playback for super bandwidth) **IVC 9000-M (could record and playback video in the 655-line/ 48 field per second (24 frame/s) video standard) **IVC 9000-W-M (An IVC 9000-M with options from the 9000-W added to it, enabling both 8 MHz wideband video ...
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1 Inch Type C Videotape
1–inch Type C (designated Type C by SMPTE) is a professional reel-to-reel analog recording helical scan videotape format co-developed and introduced by Ampex and Sony in 1976. It became the replacement in the professional video and broadcast television industries for the then-incumbent 2–inch quadruplex videotape (2–inch Quad for short) open-reel format. Additionally, it replaced the unsuccessful type A format, also invented by Ampex, and, primarily in mainland Europe, it supplemented the type B format, invented by the Fernseh division of Bosch, but it was replaced by type C format also there. Technical detail Compared to Quad, Type C had a smaller size, comparative ease of operation, and slightly higher video quality. 1–inch Type C is capable of "trick-play" functions such as still, shuttle, and variable-speed playback, including slow motion. 2–inch quadruplex videotape machines lacked these capabilities, due to the segmented manner in which it re ...
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Type A Videotape
1-inch type A (designated Type A by SMPTE) is a reel-to-reel helical scan analog recording videotape format developed by Ampex in 1965, that was one of the first standardized reel-to-reel magnetic tape formats in the 1–inch (25 mm) width; most others of that size at that time were proprietary. It was capable of 350 lines. Usage Type A was developed as mainly an industrial and institutional format, where it saw the most success. It was not widely used for broadcast television, since it did not meet Federal Communications Commission (FCC) specifications for broadcast videotape formats; the only format passing the FCC's muster at the time was the then-industry-standard 2-inch quadruplex. The Type A format received broad use by the White House Communications Agency from 1966 to 1969. The WHCA, under U.S. President Lyndon B. Johnson, used the format to videotape television broadcasts off the air or from direct White House feeds. The WHCA recorded progra ...
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