Tagged: tape

Dictaphone Dictet (1957 – early 1960s)

The Dictaphone Dictet was a portable dictation device introduced by the Dictaphone Corporation in 1957. It was perhaps the earliest magnetic tape dictation system – at the time of its introduction, most office dictation systems were using discs or belts onto which grooves were pressed, such as the SoundScriber, Audograph, or Dictaphone’s own Dictabelt system. An earlier portable system, the Protona Minifon used wire recording.

The Dictet was fully transistorised and weighed 1.2kg. The cassette had a metal shell and could record up to 60 minutes (30 minutes per side) on ¼-inch tape that ran at 2½ inches per second. Using special mercury batteries, the Dictet could operate for 20 hours.

The Dictet lasted until at least 1962, but it is unclear how much longer it lasted against newer competitors such as the Compact Cassette of 1963.

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Philips EL 3581 (1958 – early 1960s)

The Philips EL 3851 was an office dictation machine introduced by Philips (known as Norelco in the US) in 1958 and was one of the earliest magnetic tape dictation systems (the Dictaphone Dictet was launched shortly before it). At the time of its introduction, most dictation systems were using discs or belts onto which grooves were pressed, such as the Dictabelt, SoundScriber and Audograph systems.

Although the EL 3851 uses a cartridge so no threading is required, the tape is housed on two separate 3-inch reels with ¼-inch tape and cine spindle holes suitable for domestic open reel tape recorders. Removing a clip from the cartridge shell allows the reels to be removed.

Like some other dictation machines, the microphone also doubles as a speaker, and contains some tape controls. A foot pedal and external speaker were also available.

Philips later introduced the much smaller Compact Cassette format in 1963, followed by the mini-cassette in 1967 and it doesn’t appear the EL 3851 was produced for long.

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MPEG IMX (2001 – 2016)

MPEG IMX (also known as D10) was a standard-definition digital video cassette format introduced by Sony in 2001 and was part of the Betacam family of professional video formats. It was priced between Sony’s Betacam SX and the more expensive Digital Betacam, and was intended to compete with the Panasonic DVCPRO 50 system. As the name suggests, MPEG IMX recorded in MPEG video format, in case MPEG-2 using only I-frames and 8 channel audio.

Like other Betacam formats, tape width was ½ inch and cassettes were available in small or large form factors, with the S size holding up to 60 minutes of video, and the L size up to 184 minutes. To distinguish MPEG IMX tapes from other Betacam formats, the shells were coloured green. Metal particle tape was used.

All IMX video recorders could playback Betacam SX tapes, and some could playback Digital Betacam as well as analogue Betacam and Betacam SP tapes, the video from which could be encoded into MPEG-2 format. Only IMX tapes could be used for recording in IMX video recorders.

Like all Betacam formats, no new MPEG IMX video recorders are being made, having been discontinued in 2016.

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Exatron Stringy Floppy (1978 – 1986)

The Exatron String Floppy was introduced in 1978, and was an endless loop tape cartridge system for microcomputers. At the time, floppy disk systems were still expensive, and cassette tapes were very slow. Despite the name, so-called stringy floppy systems are unrelated to floppy disks.

The tape cartridges, called wafers, contained a 1/16-inch loop of mylar-based chrome dioxide tape, in different lengths according to the capacity of the wafer. The smallest wafer contained 5 feet of tape and could hold 4 KB of data, and the longest was 75 foot and, capable of holding 64 KB of data. A 16 KB file took just 24 seconds to load.

The Exatron Stringy Floppy system was most commonly used with the TRS-80 range of computers, and did not require an expansion interface. By 1982, the price has fallen to $99.50. As well as being used to save data, software, including programs and games, was available on Stringy Floppy wafers.

Although popular with TRS-80 owners, the system could be unreliable, and as the price of faster and more reliable floppy disk drives fell they became less attractive. They continued to be advertised until 1986.

Similar stringy floppy tape systems were available during the 1980s, including the Sinclair ZX Microdrive, and the Rotronics Wafadrive.

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1-inch Type B (1975 – 1980s)

1-inch Type B (also known as B-Format) was an open reel magnetic tape format for professional analogue video recording.

It was introduced by Bosch in 1976 for use in its BCN line of video recorders and although it found success in continental Europe, 1-inch Type C was more successful in the UK and US. Unlike Type C, Type B in its standard form could not perform trick-play operations such as slow-motion or frame step play, due to the way the each field was segmented over 5 or 6 tracks (Type C recorded one frame per helical scan). An expensive digital framestore was needed to perform trick-play operations.

Type B had a standard capacity of 96 minutes on a reel, although later this was increased to 120 minutes. Long play versions eventually became available that could fit up to 6 hours on one reel.

Video quality was excellent, and as well as standard recording/playback machines, portable and random access cart machines were available.

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Preservation / Migration

media stability 5obsolescence 5

HDCAM SR (2003 – 2016)

HDCAM SR (Superior Resolution) was a professional high-definition digital video cassette format, introduced by Sony in 2003 as a higher quality variant of its existing HDCAM system.

Like other Betacam-related formats, HDCAM SR cassettes were available in large and small sizes, and had the same tape lengths as Digital Betacam (up to 40 minutes for S and 124 minutes for L tapes).

It used higher particle density tape allowing an increased bit rate (a choice or 440 or 880 Mbps). Like HDCAM, it was commonly used in high-definition television production.

Sony HDCAM SR tapes were black with a cyan lid and contained a 1K memory chip to store metadata about the tape.

In 2016, Sony announced that it was ceasing production of its remaining ½-inch video tape recorders and players, including those for the HDCAM SR format.

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HDV (2003 – 2011)

HDV was a high-definition digital video format for camcorders. Because of its high quality, it has been used for broadcast television as well as amateur video recording. JVC was the first company to release a HDV camcorder in 2003, with Sony and Canon producing camcorders later.

HDV video can be recorded at 720p and 1080p, sometimes referred to as HDV1 and HDV2 respectively.

Although special HDV tapes are available, their use was not required as the tape formulation (Metal Evaporate) is the same as standard MiniDV cassettes. One Sony camera could also use the large DV cassette format. HDV devices could usually play and record in DV format as well as HDV.

Accessories were available to allow HDV camcorders to record to non-tape media such as CompactFlash cards.

By 2011, Canon, JVC and Sony had discontinued their HDV products, and invested instead in fully tapeless formats such as XDCAM.

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D-VHS (1998 – 2007)

D-VHS was a later variant of VHS that recorded digitally, and was introduced in 1998. It was developed by the originator of VHS, JVC, along with Hitachi, Matsushita, and Philips.

D-VHS used MPEG recording, and could record in standard or high-definition.  There were several different recording speeds available, so a tape could have a variety of different capacities, for example a DF-300 tape that could hold 300 minutes at standard speed, could hold as much as 2100 minutes (35 hours) at LS7 (low speed, one seventh of the standard speed) if the machine was capable of using the very slowest speed. High-definition recordings reduced the capacity of the tape by half. Standard speed recordings had a higher bandwidth than DVD.

D-VHS tapes had a second hole on their underside that identified them to the recorder as being D-VHS tapes, and to record in D-VHS mode. Where the hole was missing, the machine would record in VHS or S-VHS format. VHS and S-VHS tapes could be played in the machine.

Unfortunately, sales of D-VHS recorders were poor, and so the price of them never fell greatly.

In 2002, a small number of pre-recorded D-VHS tapes were released under the D-Theater brand by four film-studios. However, despite being virtually identical to D-VHS, D-Theater tapes could only be played on D-VHS players with the D-Theater logo. D-Theater did provide much better video quality than DVD, at a time when high-definition formats such as Blu-Ray and HD-DVD were yet to be introduced.

The last D-Theater title was released in 2004, but D-VHS recorders were listed on the JVC website until 2007.

ADAT (Alesis Digital Audio Tape) (1992 – 2003)

ADAT was a digital audio recording format, and was aimed at the professional studio market. It was introduced by Alesis and the first recorders were shipped in 1992.

ADAT could record up to 8 tracks, but multiple machines could be connected and synchronised to create recordings with up to 128 tracks. At the time, the only alternatives were 2 track DAT machines or very expensive digital open reel (DTRS was introduced a year later). ADAT was very sucessful, partly due to its affordability, and over 110,000 ADAT recorders were sold worldwide.

The recorder used S-VHS cassettes as the recording medium. Although intended for analogue video recording, these tapes were ideal for ADAT, with their width allowing for 8 tracks, good quality, and easy availability at the time. Although specially made S-VHS cassettes were available for the ADAT format, any premium-quality S-VHS video cassette could be used, though it was recommended to be no more than 120 minutes long (when used for ADAT, up to 40 minutes per tape was possible).

The first generation of ADAT recorders (also known as ‘Blackface’) recorded at 16 bits per sample (ADAT Type I). Later generations supported 20 bits per sample (ADAT Type II) but were backward compatible with recordings from the first generation.

ADAT was discontinued in 2003, but the name lived on in the ADAT HD24, a hard-drive based recorder.

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Coleco Adam High Speed Digital Data Pack (1983 – 1985)

The Coleco Adam was a home computer introduced by Coleco in 1983. It was available as a standalone computer, or could be bought as an expansion pack for the ColecoVision game console.

Like other home computers of the time, the Coleco Adam used a tape drive as one means to store programs and data, but this was not a standard Compact Cassette drive. The dual ‘Adam High Speed Digital Data Pack’ tape drives used a slightly modified type of Compact Cassette that ran at much higher speed than usual, had a different configuration of holes in the shell, and used thicker tape. These could store 256 KB, and ran at 20 inches per second (ips) when reading/writing and and 80 ips when rewinding. Blank Digital Data Packs  were supplied pre-formatted and could not be formatted by the user.

As well as the Digital Data Pack drives, the Adam had a ROM cartridge slot that accepted all ColecoVision cartridges as well as its own (it could play ColecoVision games even as a standalone computer). Later in production, a 5.25-inch disk drive was made available as an accessory.

The Coleco Adam had other unusual features such as a dedicated daisywheel printer (that also contained the power supply), built-in word-processing software, and the CP/M operating system as an option.

Unfortunately, delays in its introduction, and build quality issues led to it being discontinued in 1985. One particular problem was that tapes left in the drives or near the machine when it was turned on could suffer data loss.

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