A Super DLT I tape cartridge

Digital Linear Tape (DLT) (previously called CompacTape) is a magnetic tape data storage technology developed by Digital Equipment Corporation from 1984 onwards. In 1994 the technology was purchased by Quantum Corporation, who currently manufactures drives and licenses 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. Download high resolution version (800x644, 63 KB)Description: Photograph of a Super DLT I tape cartridge (capacity 160 GB). ... Download high resolution version (800x644, 63 KB)Description: Photograph of a Super DLT I tape cartridge (capacity 160 GB). ... Magnetic tape has been used for data storage for over 50 years. ... The DEC logo Digital Equipment Corporation was a pioneering American company in the computer industry. ... Quantum Corporation is a manufacturer of tape drive products, based in San Jose, California. ... For album titles with the same name, see 2002 (album). ...

History

DEC launched the TK50 tape drive for the MicroVAX II minicomputer 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 The TK50 was superseded in 1987 by the TK70 drive and the 48-track CompacTape II cartridge, capable of storing 294 MB.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 capacity to 2.6 GB. Later drives improved the data density of the DLTtape III cartridge into the early 1990s, up to 10 GB. The DLTtape IV cartridge was introduced by Quantum in 1994, with increased tape length and data density, initially offering 20 GB per tape. Super DLTtape, originally capable of up to 110 GB, was launched in 2001. save Y100!!!!!!!!!!!!!!!! ... Minicomputer (colloquially, mini) is a largely obsolete term for a class of multi-user computers which make up the middle range of the computing spectrum, in between the largest multi-user systems (traditionally, mainframe computers) and the smallest single-user systems (microcomputers or personal computers). ...

Technology

DLT uses linear serpentine recording with multiple tracks on half-inch (12.7 mm) wide tape. The cartridges contain a single reel and the tape is pulled out of the cartridge by means of a leader tape attached to the takeup reel inside the drive. The drive leader tape is buckled to the cartridge leader during the load process. Tape speed and tension are controlled electronically via the reel motors; there is no capstan. The tape is guided by 4 to 6 rollers that touch only the back side of the tape. Tape material is metal particle tape (MP/AMP.) In various types of electronic equipment, a cartridge can refer one method of adding different functionality or content (e. ... This movie film reel has film wrapped around it. ... Compact audio cassette Magnetic tape is a non-volatile storage medium consisting of a magnetic coating on a thin plastic strip. ... Capstans are found in the mechanisms of tape recorders in which they have a similar function to nautical capstans. ...

SDLT adds an optical servo system that reads servo patterns on the back of the tape, in order to keep the data tracks on the front of the tape correctly aligned with the read/write heads. This is important for newer tape media, which have very thin dense data tracks; 256, 384 and 768 data tracks on a half inch wide tape are now common. Small R/C servo mechanism 1. ...

DLT7000 and 8000 tilt the head forward and backward to reduce crosstalk between adjacent tracks through azimuth; this is called Symmetric Phase Recording. Azimuth is the horizontal component of a direction (compass direction), measured around the horizon, from the north toward the east (i. ... Tape recording technology developed by Quantum Corporation packs data across a tapes recording surface by writing adjacent tracks in a herringbone pattern: track 0 = , track 1 = /////, track 2 = , track 3 = /////, etc. ...

All (S)DLT drives support hardware data compression. The often-used compression factor of 2:1 is optimistic and generally only achievable for text data; a more realistic factor across a file system is 1.3:1 to 1.5:1. In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. ...

Media are guaranteed for 30 years of data retention under specified environmental conditions; however, they are easily damaged by mishandling (dropping or improper packaging during shipment.)

Current manufacturers of cartridges for the DLT/SDLT market are Fujifilm, Hitachi/Maxell and Imation. VStape is made by Sony. All other companies/brands (even Quantum) are contractors and/or resellers of these companies. Fujifilm Holdings Corporation, or Fujifilm, is a Japanese company known for its photographic film and cameras. ... Maxell is a Japanese company, which manufactures consumer electronics. ... An Imation USB Flash Drive and CD-R Imation Corporation NYSE: IMN is an American corporation spun off from 3M, with a worldwide presence that produces mainly data storage products. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $68. ...

A new naming convention took effect in 2005, calling the performance line DLT-S and the value line DLT-V. Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ...

In February 2007, Quantum stopped developing the next generations of DLT drives (S5 and V5) after insufficient market acceptance of the S4 and V4 drives, shifting its drive strategy to LTO. Year 2007 (MMVII) is now the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... Linear Tape-Open (or LTO) is a magnetic tape data storage technology developed as an open alternative to the proprietary Digital Linear Tape (DLT). ...

Generations

Drives

DSSI is also an early variant of the SCSI disk drive interface, manufactured by DEC and appearing in many late 80s and early 90s VAX and DECsystem servers. ... This article or section does not cite any references or sources. ... DSSI is also an early variant of the SCSI disk drive interface, manufactured by DEC and appearing in many late 80s and early 90s VAX and DECsystem servers. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not adequately cite its references or sources. ... Gigabit Ethernet (GbE) is a term describing various technologies for transmitting Ethernet packets at a rate of a gigabit per second, as defined by the IEEE 802. ... “FTP” redirects here. ... HTTP (for HyperText Transfer Protocol) is the primary method used to convey information on the World Wide Web. ... This article or section does not cite any references or sources. ... This article or section does not adequately cite its references or sources. ... 2. ... Gigabit Ethernet (GbE) is a term describing various technologies for transmitting Ethernet packets at a rate of a gigabit per second, as defined by the IEEE 802. ... “FTP” redirects here. ... HTTP (for HyperText Transfer Protocol) is the primary method used to convey information on the World Wide Web. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... This article or section does not cite any references or sources. ... First generation (1. ...

Media

Tapes written in value series drives can typically be read (and often written) in higher end drives of a similar vintage. Check the specs for your specific drive to find out its interoperability options.

External links

• History of DLTtape™ Technology, from TK50 1984 to SDLT1 2001
• A list of SDLT tapes and some info
• DLTtape™ Handbook, 8th ed. (Quantum 2001) (PDF)
• DLT Roadmap at dlttape.com
• Quantum Corp. DLT drive page
• Obituary of Dr. Fred Hertrich, "father" of DLT

Standards

• ECMA 197 Specification of DLT 2. [1]
• ECMA 209 Specification of DLT 3. [2]
• ECMA 231 Specification of DLT 4. [3]
• ECMA 258 Specification of DLT 3-XT. [4]
• ECMA 259 Specification of DLT 5. [5]
• ECMA 286 Specification of DLT 6. [6]
• ECMA 320 Specification of SDLT-1. [7]