Tagged: magnetic

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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Minifon wire reel (1959 – 1967)

The Minifon name was applied to a range of miniature wire recorders introduced initially by the German company Monske & Co GmbH in 1951, and then produced by Protona GmbH from 1952 until 1967, although they were also sold under the Telefunken, ITT and EMI brands.

The recorders ran on batteries, and could record over 2 hours on a single reel of wire (later models allowed for 5 hours of recording). As the reels turn, the recording/playback head moved up and down so the wire was spooled evenly on each reel.

They were popular for covert recordings, and an accessory microphone that was made to look like a wristwatch was available. Minifon recorders were sold in overseas markets such as the US and UK.

In 1959 the Minifon Ataché was introduced, using a tape cartridge for the first time, but the wire-based recorders continue to be produced until Protona ceased production of all Minifon models in 1967.

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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.

Iomega Zip 250 (2001 – 2003)

Zip was a high-capacity floppy disk format originally introduced in 1995 by Iomega. Initially, it had a capacity of 100 MB, later increased to 250 MB in 2001, and again to 750 MB in 2002.

The Zip 250 drives were available in a wide variety of interfaces; parallel port, USB 2.0 and FireWire for exernal drives and IDE or SCSI for internal drives.

Although the disks looked identical to Zip 100 disks, they could not be used in the smaller capacity drive and are automatically ejected. They could however be read and written to by the later Zip 750 drives. Zip 250 drives could read and write to the older Zip 100 disks. A variant on the Zip 250, the Zip U250 was also launched in 2001; the U250 disks contained titanium particles in the media to improve the operation of the drives, and were also self-cleaning. The U250 discs were full compatible with Zip 250 drives despite their different shape.

Even before the introduction of the Zip 250, sales of Zip drives had begun falling due to the falling cost of CD-R and CD-RW disks, followed by USB memory sticks.

All Zip variants were discontinued in 2003.

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Pye magnetic disc (1953 – late 1950s)

From around 1953 to the late 1950s the UK company Pye produced the Record Maker. This device allowed the user to record onto pre-grooved 12-inch discs that had a magnetic coating. Users could record to the disc at one of four different speeds (16⅔, 33⅓, 45 and 78rpm) but the slower the speed, the poorer the quality of recording.

The Pye Record Maker could also be used to play ordinary phonograph records, with an optional pick-up head attachment.

Telefunken also made a similar machine, but this could not play phonograph discs, used a larger centre hole, and had a single speed of 10rpm.

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