The Dictabelt, in early years and much less commonly also called a Memobelt, is an
analog audio recording medium commercially introduced by the
American
American(s) may refer to:
* American, something of, from, or related to the United States of America, commonly known as the "United States" or "America"
** Americans, citizens and nationals of the United States of America
** American ancestry, pe ...
Dictaphone
Dictaphone was an American company founded by Alexander Graham Bell
that produced dictation machines. It is now a division of Nuance Communications, based in Burlington, Massachusetts.
Although the name "Dictaphone" is a trademark, it has bec ...
company in 1947. Having been intended for
recording dictation and other speech for later transcription, it is a
write-once-read-many medium consisting of a thick transparent
vinyl
Vinyl may refer to:
Chemistry
* Polyvinyl chloride (PVC), a particular vinyl polymer
* Vinyl cation, a type of carbocation
* Vinyl group, a broad class of organic molecules in chemistry
* Vinyl polymer, a group of polymers derived from vinyl m ...
(according to a 1960s Dictaphone user manual: cellulose acetate butyrate) plastic belt wide and around. The belt is loaded onto a pair of metal cylinders, put under tension, then rotated like a
tank tread. It is inscribed with an audio-signal-modulated
helical
Helical may refer to:
* Helix, the mathematical concept for the shape
* Helical engine, a proposed spacecraft propulsion drive
* Helical spring, a coilspring
* Helical plc, a British property company, once a maker of steel bar stock
* Helicoil
A t ...
groove by a
stylus
A stylus (plural styli or styluses) is a writing utensil or a small tool for some other form of marking or shaping, for example, in pottery. It can also be a computer accessory that is used to assist in navigating or providing more precision w ...
which is slowly moved across the rotating belt. Unlike the stylus of a record cutter, the Dictabelt stylus is blunt and in recording mode it simply impresses a groove into the plastic rather than engraving it and throwing off a thread of waste material. The Dictabelt system was popular, and by 1952, made up 90% of Dictaphone's sales.
Dictabelts were more convenient and provide better audio quality than the reusable
wax cylinders
Phonograph cylinders are the earliest commercial medium for Sound recording and reproduction, recording and reproducing sound. Commonly known simply as "records" in their era of greatest popularity (c. 1896–1916), these hollow cylinder, cylind ...
they replaced. The belts can be folded for storage and will fit into an ordinary letter-size envelope. However, the plastic loses flexibility as it ages. If a belt is stored sharply folded for a long time, it will become permanently creased and unplayable without special treatment. Dictabelts were red until 1964, blue from 1964 to 1975, then purple until they were discontinued around 1980. Each has a capacity of about 15 minutes at the standard speed. At least one Dictaphone model featured a half-speed, low-fidelity 30-minute option.
In the 1960s,
Virginia
Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth ar ...
required that all of
its circuit courts be outfitted with Dictabelt machines.
Along with a
Gray Audograph
The Gray Audograph was a dictation machine format introduced in 1945. It recorded sound by pressing grooves into soft vinyl discs, like the competing, but incompatible, SoundScriber. It was manufactured by the Gray Manufacturing Company of Hartf ...
sound recorder, a Dictabelt recorded the police department radio channels in Dallas, Texas, during the
John F. Kennedy assassination
John F. Kennedy, the 35th president of the United States, was Assassination, assassinated on Friday, November 22, 1963, at 12:30 p.m. Central Time Zone, CST in Dallas, Dallas, Texas, while riding in a presidential motorcade through Deale ...
.
These recordings were reviewed by the
United States House Select Committee on Assassinations
The United States House of Representatives Select Committee on Assassinations (HSCA) was established in 1976 to investigate the assassinations of John F. Kennedy and Martin Luther King, Jr. in 1963 and 1968, respectively. The HSCA completed its i ...
(HSCA).
See also
*
John F. Kennedy assassination Dictabelt recording
The John F. Kennedy assassination Dictabelt recording was a Dictabelt recording from a motorcycle police officer's radio microphone stuck in the open position that became a key piece of evidence cited by the House Select Committee on Assassinati ...
References
External links
Image- ''History of the Dictation Equipment'' Industry (archived)
Funny, That Doesn’t Sound Like Me- Article with several images
Vintage Tech: Dictaphone Dictabelt 800 Record Cutter ''databits'' via YouTube, uploaded on 2 July 2016
Audiovisual introductions in 1947
Audio storage
1947 in technology
Products introduced in 1947
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