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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 *Storage Technology Corporation Storage Technology Corporation (StorageTek or STK, earlier STC) was a data storage technology company headquartered in Louisville, Colorado. New products include data retention systems, which it calls "information lifecycle management" (ILM). It ... Storage media {{Compu-hardware-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Storage Media
In communications and computing a machine-readable medium, or computer-readable medium, is a medium capable of storing data in a format readable by a mechanical device (rather than human readable). Examples of machine-readable media include magnetic media such as magnetic disks, cards, tapes, and drums, punched cards and paper tapes, optical discs, barcodes and magnetic ink characters. Common machine-readable technologies include magnetic recording, processing waveforms, and barcodes. Optical character recognition (OCR) can be used to enable machines to read information available to humans. Any information retrievable by any form of energy can be machine-readable. Examples include: *Acoustics *Chemical **Photochemical *Electrical **Semiconductor used in volatile RAM microchips ** Floating-gate transistor used in non-volatile memory cards **Radio transmission *Magnetic storage *Mechanical ** Tins And Swins *** Punched card *** Paper tape **** Music roll *** Music box cyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Corporation
Quantum Corporation is a data storage, management, and protection company that provides technology to store, manage, archive, and protect video and unstructured data throughout the data lifecycle. Their products are used by enterprises, media and entertainment companies, government agencies, big data companies, and life science organizations. Quantum is headquartered in San Jose, California and has offices around the world, supporting customers globally in addition to working with a network of distributors, VARs, DMRs, OEMs and other suppliers. History Quantum was founded in 1980 as Quantum Software Systems Inc. By 1984, it led the market for mid-capacity 5.25-inch drives. That year, a subsidiary was launched called Plus Development to focus on the development of hardcards. Plus Development became a successful designer of 3.5-inch drives with Matsushita Kotobuki Electronics (now Panasonic) as the contract manufacturer. By 1989, Quantum led the compact drive market. The company ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azimuth Recording
Azimuth recording is the use of a variation in angle between two recording heads that are recording data so close together on magnetic tape that crosstalk would otherwise likely occur. Normally, the head is perpendicular to the movement of the tape, and this is considered zero degrees. However, if the heads are mounted at slightly different angles (such as ±7 degrees in VHS), destructive interference will occur at high frequencies when reading data recorded in the cross-talking channel but not in the channel that is intended to be read. At low frequencies relative to the maximum allowed by the head gap, however, this technique is ineffective. Thus one head is slanted slightly leftwards and the magnetic gap of the other head slanted slightly rightwards. To look at it another way, channel A sees the channel B data stretched out in time, hence the technique has a low-pass effect on noise intruding from another channel. Every videotape system was designed to put as much video as pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Equipment Corporation
Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until forced to resign in 1992, after the company had gone into precipitous decline. The company produced many different product lines over its history. It is best known for the work in the minicomputer market starting in the mid-1960s. The company produced a series of machines known as the PDP line, with the PDP-8 and PDP-11 being among the most successful minis in history. Their success was only surpassed by another DEC product, the late-1970s VAX "supermini" systems that were designed to replace the PDP-11. Although a number of competitors had successfully competed with Digital through the 1970s, the VAX cemented the company's place as a leading vendor in the computer space. As microcomputers improved in the late 1980s, especially w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Linear Tape
Digital Linear Tape (DLT; previously called CompacTape) is a magnetic-tape data storage technology developed by Digital Equipment Corporation (DEC) from 1984 onwards. In 1994, the technology was purchased by Quantum Corporation, who manufactured drives and licensed the technology and trademark. A variant with higher capacity is called Super DLT (SDLT). The lower cost "value line" was initially manufactured by Benchmark Storage Innovations under license from Quantum. Quantum acquired Benchmark in 2002. In 2007 Quantum stopped developing DLT drives, shifting its strategy to LTO. History DEC launched the TK50 tape drive for the MicroVAX II and PDP-11 minicomputers in 1984. This used 22-track CompacTape I cartridges, storing 94 MB per cartridge. The TK50 was superseded in 1987 by the TK70 drive and the 48-track CompacTape II cartridge, capable of storing 294 MB. In 1989, the CompacTape III (later DLTtape III) format was introduced, increasing the number of tracks to 128 and cap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linear Tape-Open
Linearity is the property of a mathematical relationship ('' function'') that can be graphically represented as a straight line. Linearity is closely related to '' proportionality''. Examples in physics include rectilinear motion, the linear relationship of voltage and current in an electrical conductor (Ohm's law), and the relationship of mass and weight. By contrast, more complicated relationships are ''nonlinear''. Generalized for functions in more than one dimension, linearity means the property of a function of being compatible with addition and scaling, also known as the superposition principle. The word linear comes from Latin ''linearis'', "pertaining to or resembling a line". In mathematics In mathematics, a linear map or linear function ''f''(''x'') is a function that satisfies the two properties: * Additivity: . * Homogeneity of degree 1: for all α. These properties are known as the superposition principle. In this definition, ''x'' is not necessarily a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Tape Format
Digital Tape Format is a magnetic tape data storage format developed by Sony. It uses a 1/2" wide tape, in a cassette with two reels, which is written and read with a helical scan process. The format is described by the ECMA 248 (adopted June 1998) and ISO/IEC 15731 standards. There are two sizes of tape cassettes, "S" and "L". Generations Notes: * Both used ALDC compression * DTF-2 used Fibre Channel or SCSI interfaces * The tape cassettes are similar to those of Sony Betacam Betacam is a family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, "Betacam" singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself. Al .... External links ECMA 248Specification of DTF-1ECMA 315Specification of DTF-2Brochure for DTF-1 drive with specs Computer storage tape media {{compu-storage-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Tape
Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic tape could with relative ease record and playback audio, visual, and binary computer data. Magnetic tape revolutionized sound recording and reproduction and broadcasting. It allowed radio, which had always been broadcast live, to be recorded for later or repeated airing. Since the early 1950s, magnetic tape has been used with computers to store large quantities of data and is still used for backup purposes. Magnetic tape begins to degrade after 10–20 years and therefore is not an ideal medium for long-term archival storage. Durability While good for short-term use, magnetic tape is highly prone to disintegration. Depending on the environment, this process may begin after 10–20 years. Over time, magnetic tape made in the 1970 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 7-track, later 9-track tape. Modern magnetic tape is most commonly packaged in cartridges and cassettes, such as the widely supported Linear Tape-Open (LTO) and IBM 3592 series. The device that performs the writing or reading of data is called a tape drive. Autoloaders and tape libraries are often used to automate cartridge handling and exchange. Compatibility was important to enable transferring data. Tape data storage is now used more for system backup, data archive and data exchange. The low cost of tape has kept it viable for long-term storage and archive. Open reels Initially, magnetic tape for data storage was wound on reels. This standard for large computer systems persisted through the late 1980s, with steadily increasing capacity due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Storage Technology Corporation
Storage Technology Corporation (StorageTek or STK, earlier STC) was a data storage technology company headquartered in Louisville, Colorado. New products include data retention systems, which it calls "information lifecycle management" (ILM). Its remaining product line is now part of Oracle Corporation, and marketed as Oracle StorageTek, with a focus on tape backup equipment and software to manage storage systems. History In 1969 four former IBM engineers— Jesse Aweida, Juan Rodriguez, Thomas S. Kavanagh, and Zoltan Herger—founded the Storage Technology Corporation. The headquarters was in Louisville, Boulder County, Colorado. In the 1970s, StorageTek launched its Disk Products division. After a failed attempt to develop an IBM-compatible mainframe, and an optical disk product line, the company filed for Chapter 11 bankruptcy protection in 1984. Starting in 1987, new management invested in an automated tape library product line that "picked" tapes from a silo-like con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
