By Adam Stowell
• The following presentation will escort you
through the more recent history of storage
media. Starting with the introduction of
magnetic recording to what lies ahead in the
future.
• Also be on the lookout for the Gwyndolyn
Largebottom symbol to give you a little
more information and pictures.
• Toward the end of the Industrial Age is where our journey
begins with an American mechanical engineer named
Oberlin Smith. He came up with the idea of recording
electrical signals produced by the telephone on a steel
wire. The idea was presented to him after a visit to
Thomas A. Edison’s laboratory. After spending 10 months
on a reel-to-reel recording system, Smith filed a “patent
caveat”, but not a formal patent, deciding not to pursue the
idea. He did publish the concept in the journal, “Electrical
World”.
• Gwyndolyn
Largebottom says that
“Smith had 70 patents
ranging from devices
to extract boiling eggs
at a certain time to
inventing or
improving die
presses.”
• Picking up where Smith left off, Valdemar Poulsen started experimenting with
recording electrical signals on steel wire. By the end of 1898 he filed a patent
with the Danish Patent Office for the Telegraphone. In the UK the following
year a patent was file that foresaw the future of today’s disks and tapes.
"Instead of a cylinder with a helical steel wire there may be uses as a receiving
device a steel band, supported if necessary on an insulating material and
brought under the action of an electromagnet. Such an arrangement has the
advantage that a steel band of an desired length may be used. Instead of a
cylinder there may be used a disk of magnetisable material over which the
electromagnet may be conducted spirally; or a sheet or strip of some insulating
material such as paper may be cover with a magnetisable metallic dust and
may be used as the magnetisable surface. With the aid of such a strip which
may be folded, a message received at any place provided with the new
apparatus may be sent to another place where it may be repeated by passing
the strip through the apparatus at that place."
• Gwyndolyn
Largebottom says
“Poulsen also
designed spark
transmitters and other
inventions. He won
honors and medals
from institutions in his
native Denmark.”
• Williams tube • DECTape
• Core memory • Cassette and
• Plated wire memory cartridge tapes
• Delay line memory • Magnetic drum
storage
• Magnetic Tape
• English Electric
• Reel of 1/2" 9-Track Deuce Drum (1957)
Tape (1970)
• In 1955, commercial computers used tubes for logic, cores for short-
term memory, head-per-track drums for intermediate storage and tapes
on reels for longer-term memory.
• “The first functional prototype weighed in at one ton and took up 300
cubic feet. Fifty double-sided aluminum magnetic disks, each 24-
inches in diameter, rotated at 1200 revolutions per minute on a
common shaft, using externally pressurized air fed through the
read/write heads to support the heads over a set of 24-inch disks. The
drive's capacity was 5 megabytes, an unheard of accomplishment for
its time.”
• The prototype was called the IBM 305 RAMAC (Random Access
Method of Accounting and Control).
• In addition to his work on the
RAMAC, Rey Johnson also
distinguished himself in 1934 as
the inventor of the mark-sense
reader. The media for this
device is familiar to the
generations of students who
took tests by filling in the space
between the vertical dotted lines
on the test firm, using the
mandatory #2 pencil.
• Burroughs ILLIAC IV 80MB Disk Drive
(1972)
• Disk packs and cartridges
• IBM 1311 Disk pack drive (1963)
• Diablo Disk Cartridge (1973)
• Flexible Disk Drive:The IBM "Minnow"
• Magnetic cards
• Intel EPROM (1975-85)
• In 1969 IBM was the first to manufacture the diskette. It was used to
load programs into the controller of a rigid disk drive. It was released
publicly in 1971. It was given the nickname “floppy disk” due to its
ability to bend.
• “First designed to use 8" diameter media, 5.25" media (1976) and then
3.5" media (1981) became predominant as improved technology
increased storage capacity per unit area and form factors shrank.
Various other sizes were offered, but were not adopted by the
computer industry. The standards fights were brutal!
• When first introduced, capacity was about 100 kilobytes (KB) per disk
for the 8" diskette. Typical 5.25" diskettes offered 360 KB, then 1.2 or
1.6 megabytes (MB). The 3.5" units were typically .7 or 1.4 MB.
Higher capacity variants were available, but never caught on because
of expense and standards disputes.”
• “Optical disk drives use lasers to read and write on the disk surface.
Attempts to design optical drives began in the 1960s, but the CD-
ROM, which appeared in the 1980s, was the first successful optical
storage device for computers. Originally a read-only device, read-write
versions appeared in the early 1990s. The 500 to 700 MB capacity of
CD-ROM made it a success as a distribution medium for software,
which was undergoing explosive growth in memory requirements.”
• “DVD drives, also laser read and written, were the next major success.
With 4.7 GB per side, the disks were suitable for storing a digitized
feature-length movie. But standards disputes and royalty issues
delayed the introduction of writable DVD formats, and as of early
2002there is yet no universal format.”
• Flash memory
• Specialized Alphabets
and Symbol Sets
• Magnetic Ink Character
Recognition
• Automating storage
• Advanced magnetic recording media
• Magnetic Random Access Memory
• Atomic Force Microscopy (AFM) and
Thermomechanical Storage
• DNA Storage
• Holographic storage
• Quantum-level storage
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