MAGNETIC REEL TAPE

Magnetic Reel Tape■ What is it?A medium for magnetic recording, made of thin, magnetizable coating on a long, narrow strip of plastic film.

Oberlin Smith (1880)An American EngineerPublished one of the earliest works dealing with magnetic recording.“Some Possible Forms of the Phonograph”

Valdemar Poulsen (1898)A Danish Engineer

Developed the magnetic wire recorder

Fritz Pfleumer (1928)A German-Austrian engineerInvented magnetic tape for recording sound, based the invention of Valdemar Poulsen in 1898 and Oberlin Smith in 1888.Used a ferric oxide powder coating on a long strip of paper.

PropertiesType of storage Magnetic

Data access Serial accessCapacity Can be a terabyte or moreSpeed The slowest of all the storage media

from which to access dataPortability The magnetic tape is fairly small.

However, in order to be read, an external tape drive is required

Durability If used once it will last typically for 15 years.

If its used for saving data and erasing it for many times eventually the quality of

the storage will declineReliability It is a very reliable method of data

storage as long as it is not damaged

Types■Type 0 - This is the original ferric-oxide tape. ■Type 1 - This is standard ferric-oxide tape, also

referred to as "normal bias."■Type 2 - This is "chrome" or CrO2 tape. ■Type 4 - This is "metal" tape.

How it works■ Serial access

Types of Magnetic Reel

Tape

Tape RecorderAn analog device that records and plays back sounds.

Videotape

■Used for storing motion images and usually sound, as opposed to film or random-access digital media.

Data Storage■Record computer data in 1951 on the Eckert-

Mauchley UNIVAC1■Cartridges and Cassettes

Advantages and

Disadvantages

Advantages■ Cheap■ Can store large amounts of

data■ Can be set up to do the back

up overnight or over the weekend

■ Easy to edit using a traditional linear-editing system

Disadvantages■ Serial access■ Need a special place of

equipment to record and read the data on the tape

■ The data may be corrupted if the tape is placed near a strong magnetic field

■ Slow access compared to disc■ That each successive copy of

a tape loses quality compared to the original.

■ It has a tendency to stretch out over time, causing the quality of the data to deteriorate.

Causes of Magnetic

tape failure

Binder DegradationMagnetic Particle InstabilitiesSubstrate DeformationFormat Issues

Thank You

References■ http://www.tvhandbook.com/history/history_recording.htm (Tape recording

technology)■ http://www.tech-ict.com/gsc_new/computer (Magnetic tape)■ http://www.tpub.com/wets/book2397a.htm (Causes of magnetic tape failure)■ http://electronics.howstuffworks.com/gadgets/audio-music/cassette.htm (How

Tape Recorders Work)■ “Magnetic Materials”. Memory of the world. Safeguarding the documentary

heritage. A guide to standard, recommended practices and reference literature related to the presentation of documents of all kinds. ONESCO. 1998. C11. 98/W5/4

■ Radio Television Electronics, Popular Mechanics, April 1954, p.157