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General
We do NOT sell tapes. Technova Computing only offers duplication service and conversion
service. For that we will supply the necessary tapes if needed. We can only handle
data tape services. Audio or Video is not our expertise, so we cannot help you
with those products.
4mm (DAT)
We support the following 4mm DAT formats:
- DDS1
- DDS1-DCLZ
- DDS2
- DDS2-DCLZ
- DDS3
- DDS3-DCLZ
- DDS4
- DDS4-DCLZ
The abbreviation DAT means "Digital Audio Tape". As the name indicates,
the tape was developed to record music (and other analogue sources, for that matter)
as digital data. The version derived for computers uses the so-called Digital
Data Storage (DDS) format, which was defined by Sony and Hewlett-Packard. This
format uses the same basic audio format as the DAT, but also includes several
levels of error detection and correction to increase reliability.
Two different versions of the DAT exist for computers:
- DATADAT, which was used by JVC
- DAT as used by Archive, Hewlett-Packard, Sony and others
The
recording technology used is called "Helical Scan" and is derived from
the video cassette recorder. With "Helical Scan", two tracks are written
/ read simultaneously and are closely spaced for high data density. The recording
/ reading is performed by a slightly tilted rotating head, so the tracks are written
to the tape at an angle. Sub-codes that are written to each track during recording
make fast access to any position on the tape possible.
Hardware data compression (DCLZ) is often used in all the DDS formats. DCLZ has
a positive influence on both speed and capacity.
8mm (Exabyte)
We support the following 8mm formats:
- Exabyte 2501 *
- Exabyte 8200
- Exabyte 8200C
- Exabyte 8500
- Exabyte 8500C
- Exabyte 8505XL
- Exabyte 8700
- Exabyte Eliant 820
- Exabyte Mammoth-LT
- Exabyte Mammoth
For many years now, 8mm tapes have been used in the computer industry. Especially
their high storage to price ratio, made this a very popular choice for small to
medium size companies.
Most
of the well known 8mm drives are manufactured by Exabyte Corporation. There is
however, yet another protocol for 8mm drives: the Advanced Intelligent Tape (AIT).
This protocol was developed by Seagate and Sony.
All 8mm drives use a coding technique that was originally developed for Video-8
media. The technique has been modified for computer use, to perform with maximum
data reliability. This technique is called 'Helical Scan'.
QIC (Quarter Inch Cartridge)
We support the following QIC formats:
The Quarter-Inch Cartridge was developed by 3M and introduced in the early 1970s.
The technology is simple, robust and very reliable. Nevertheless, QIC has never
been able to gain a dominant market position. The sheer number of standards (well
over 120 different logical formats are known to exist) developed by a great number
of manufacturers leads to incompatibility.
In an effort to bring order in the format chaos, the "Quarter-Inch Cartridge
Standards Inc." was founded. Representatives of 12 companies involved in
manufacturing ¼-inch drives and ¼-inch media formed a committee.
This group and the standards they promote are called QIC. Apart from these 12
companies, at least 30 other companies are involved with the QIC standard.
We only support the DC600 family of tapes; we do not support the DC2000 type mini-cartridge.
The newer "multi channel" versions, the SLR/MLR, are discussed below.
All QIC formats in the following table use a recording technique called "Group
Coded Recording" (GCR).
SLR/MLR
We support the following SLR/MLR formats:
- SLR24/SLR6 (12-24GB)
- MLR1/QIC-5010 (13-26GB)
- SLR32/MLR2 (16-32GB)
- SLR50/MLR3 (25-50GB)
Since the introduction of the "multi channel" versions of the QIC drives,
the nomenclature of both the drives and the medium has been changed. The new name,
"SLRx", is according to the new type referral of these QIC formats.
"SLR" means "Scalable Linear Recording", sometimes also referred
to as "Serpentine Linear Recording".
The
"old" QIC drives use a maximum density of 46 tracks; the "new"
SLR drives start off with track densities of 144. This is an increase of over
300% while the tape width remains unchanged. The SLR drives are capable of recording
/ reading multiple tracks simultaneously through the use of track sets. Track
sets are made up of 2 tracks on the SLR24 through SLR50 drives. The SLR100 even
uses 4-track-wide track sets. The speed obviously benefits greatly from this technique.
For a short period of time, these drives and tapes were called "MLR",
which stands for "Multi channel Linear Recording". One MLR type has
survived, however: the MLR1 (13-26 GB). This format is used only in IBM environments.
The recording format is known as QIC-5010.
DLT & TKxx
We support the following DLT formats:
- TK50/TZ30
- TK70
- TK85/T826
- TK86/T860
- TK87/DLT2000/DLT2000XT
- DLT4000
- DLT7000
- DLT8000
Digital Linear Technology (DLT) is the result of a steady development of Digital
Equipment Corporation's (DEC) own adaptation of the ½-inch magnetic tape.
DEC introduced its ½-inch tape drive (the TZ30 a.k.a. TK50) in the mid-1980s
as a backup solution for their successful DEC MicroVAX system. The first true
DLT system emerged in 1989. DLT technology is currently owned by Quantum Corporation,
which acquired it in 1994. A number of OEMs have licensed DLT technology. DLT
utilizes serial serpentine recording. Multiple tracks are combined into sets of
tracks, with each track set consisting of 2 or 4 tracks, depending on the drive
used. This way, multiple tracks are written / read simultaneously, resulting in
very high speeds. For instance, the DLT8000 reaches a maximum data transfer rate
of up to 40 GB per hour provided that data compression is active.
One of the characteristics of these drives is the loading mechanism. The tapes
are pulled out of the cartridge and loaded onto a second reel in the drive. That
loading mechanism is also the main weakness of these drives. Especially the tape
leader strip is prone to damage. The tape leader strip is the end of the tape
by which the tape is pulled out of the cartridge. When the leader strip gets damaged,
a skilled technician is required to recover the data from the tape.
9 Track (½ Inch Reel)
We support the following ½ Inch Reel formats:
- 800 bpi
- 1600 bpi
- 3200 bpi
- 6250 bpi
Ever since the mid-1950s, the magnetic ½-inch reel tape has been a reliable
medium for storage and exchange of computer data. By today's standards, however,
the size and capacity are unacceptable. Especially in environments where large
amounts of data are stored, both the reels and the robotics that handle the reels
require much too much space.
The
½-inch reel tape has developed from 200 bpi (bits per inch), through 556,
800, 1600 and 3200 bpi to 6250 bpi. The recording technology on those early 200-bpi
tapes was based on decimal coding; the concept of "bytes" had not yet
been introduced. The tape density developed from 4 tracks on the early machines
to 9 Tracks on the most recent models. The technique used to record on a 9-track
tape is simple. Each track records 1 bit to make up 1 byte of data. The 9th track
is used for parity checking. Some machines use odd parity, some use even parity.
The ½-inch reel tape has been superseded by newer ½-inch technologies
such as the 3480/3490 cartridge tape drive.
3480/3490
We support the following 3480/3490 formats:
IBM developed the 3480 ½-inch-cartridge format for the purpose of data
backup and exchange in minicomputer and mainframe environments. Most mainframe
sites are equipped with this type of drive, which has become a standard in enterprise
data storage solutions.
The 3480/3490E media are relatively inexpensive and provide capacities from 200
MB to 2.4 GB with IDRC compression. Younger generations and derived versions of
this ½-inch technology (such as 3590, 3590Ext, 9490, 9840 and SD3) are
capable of higher capacities and they are much faster because they write more
tracks simultaneously.
3480/3490
drives (and their successors) use very complex technologies, often including loaders
and even library systems with integrated robotics capable of managing thousands
of tapes. This complex technology makes these drives very expensive. They are
therefore used almost exclusively in really high-end computer environments like
mainframe sites.
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