Magnetic tape

(Redirected from Magnetic tapes)

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.

7-inch reel of ¼-inch-wide audio recording tape, typical of consumer use in the 1950s70s.

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.[1] The exception is data tape formats like LTO which are specifically designed for long-term archiving.[2]

Durability edit

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.[1]

Over time, magnetic tape made in the 1970s and 1980s can suffer from a type of deterioration called sticky-shed syndrome. It is caused by hydrolysis of the binder in the tape and can render the tape unusable.[3]

Successors edit

Since the introduction of magnetic tape, other technologies have been developed that can perform the same functions, and therefore, replace it. Despite this, technological innovation continues. As of 2014 Sony and IBM continue to advance tape capacity.[4]

Uses edit

Audio edit

 
Compact Cassette

Magnetic tape was invented for recording sound by Fritz Pfleumer in 1928 in Germany.[5]

Because of escalating political tensions and the outbreak of World War II, these developments in Germany were largely kept secret. Although the Allies knew from their monitoring of Nazi radio broadcasts that the Germans had some new form of recording technology, its nature was not discovered until the Allies acquired German recording equipment as they invaded Europe at the end of the war.[6] It was only after the war that Americans, particularly Jack Mullin, John Herbert Orr, and Richard H. Ranger, were able to bring this technology out of Germany and develop it into commercially viable formats. Bing Crosby, an early adopter of the technology, made a large investment in the tape hardware manufacturer Ampex.[7]

A wide variety of audiotape recorders and formats have been developed since. Some magnetic tape-based formats include:

Video edit

 
A VHS helical scan head drum. Helical and transverse scans made it possible to increase the data bandwidth to the necessary point for recording video on tapes, and not just audio.

Some magnetic tape-based formats include:

Computer data edit

 
Small open reel of 9-track tape
 
On-scale comparison of an LTO Ultrium, Exatape, DSS-3, and D/CAS cartridges

Magnetic tape was first used to record computer data in 1951 on the Eckert-Mauchly UNIVAC I. The system's UNISERVO I tape drive used a thin strip of one-half-inch (12.65  mm) wide metal, consisting of nickel-plated bronze (called Vicalloy). The recording density was 100 characters per inch (39.37  characters/cm) on eight tracks.[8]

In 2002, Imation received a US$11.9 million grant from the U.S. National Institute of Standards and Technology for research into increasing the data capacity of magnetic tape.[9]

In 2014, Sony and IBM announced that they had been able to record 148 gigabits per square inch with magnetic-tape media developed using a new vacuum thin-film forming technology able to form extremely fine crystal particles, allowing true tape capacity of 185 TB.[4][10]

See also edit

Notes edit

References edit

  1. ^ a b Pogue, David (1 September 2016). "Digitize Those Memory-Filled Cassettes before They Disintegrate". Scientific American. Archived from the original on 19 August 2016. Retrieved 26 July 2022.
  2. ^ Coughlin, Tom. "LTO Tape Capacity Shipments Up In 2022". Forbes. Retrieved 19 December 2023.
  3. ^ "Magnetic Materials" (PDF). Memory of the World: Safeguarding the Documentary Heritage. A guide to Standards, Recommended Practices and Reference Literature Related to the Preservation of Documents of All Kinds. UNESCO. 1998. CII.98/WS/4. Retrieved 12 December 2017.
  4. ^ a b "Sony develops magnetic-tape technology with the world's highest*1 areal recording density of 148 Gb/in2". Sony Global. Archived from the original on 5 May 2014. Retrieved 4 May 2014.
  5. ^ Eric D. Daniel; C. Denis Mee; Mark H. Clark (1998). Magnetic Recording: The First 100 Years. Wiley-IEEE. ISBN 0-7803-4709-9.
  6. ^ "BBC World Service - The Documentary Podcast, A History of Music and Technology: Sound Recording". BBC. 18 June 2019. Archived from the original on 1 July 2019. Retrieved 1 July 2019.
  7. ^ Fenster, J.M. (Fall 1994). "How Bing Crosby Brought You Audiotape". Invention & Technology. Archived from the original on 4 April 2011.
  8. ^ Welsh, H. F. & Lukoff, H (1952). "The Uniservo - Tape Reader and Recorder" (PDF). American Federation of Information Processing Societies. Archived from the original (PDF) on 25 February 2015. Retrieved 21 January 2019.
  9. ^ "The Future of Tape: Containing the Information Explosion" (PDF). Archived from the original (PDF) on 13 December 2017. Retrieved 12 December 2017.
  10. ^ Fingas, Jon (4 May 2014). "Sony's 185TB data tape puts your hard drive to shame". Engadget. Archived from the original on 3 May 2014. Retrieved 4 May 2014.

External links edit