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Wire recording or magnetic wire recording was the first
magnetic recording Magnetic storage or magnetic recording is the storage of data on a magnetized medium. Magnetic storage uses different patterns of magnetisation in a magnetizable material to store data and is a form of non-volatile memory. The information is ac ...
technology, an
analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use analog ...
type of
audio storage Sound recording and reproduction is the electrical, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recording te ...
in which a magnetic recording is made on a thin
steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
wire Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is c ...
. The first crude magnetic recorder was invented in 1898 by
Valdemar Poulsen Valdemar Poulsen (23 November 1869 – 23 July 1942) was a Danish engineer who made significant contributions to early radio technology. He developed a magnetic wire recorder called the telegraphone in 1898 and the first continuous wave rad ...
. The first magnetic recorder to be made commercially available anywhere was the Telegraphone, manufactured by the American Telegraphone Company, Springfield, Massachusetts in 1903. The wire is pulled rapidly across a recording head which magnetizes each point along the wire in accordance with the intensity and polarity of the electrical
audio signal An audio signal is a representation of sound, typically using either a changing level of electrical voltage for analog signals, or a series of binary numbers for digital signals. Audio signals have frequencies in the audio frequency range of r ...
being supplied to the recording head at that instant. By later drawing the wire across the same or a similar head while the head is not being supplied with an electrical signal, the varying magnetic field presented by the passing wire induces a similarly varying electric current in the head, recreating the original signal at a reduced level. Magnetic wire recording was replaced by
magnetic tape 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 magne ...
recording by the 1950s, but devices employing one or the other of these media had been more or less simultaneously under development for many years before either came into widespread use. The principles and electronics involved are nearly identical.


History

The first wire recorder was invented in 1898 by Danish engineer
Valdemar Poulsen Valdemar Poulsen (23 November 1869 – 23 July 1942) was a Danish engineer who made significant contributions to early radio technology. He developed a magnetic wire recorder called the telegraphone in 1898 and the first continuous wave rad ...
, who gave his product the trade name Telegraphone. Wire recorders for dictation and telephone recording were made almost continuously by multiple companies (mainly the American Telegraphone Company) through the 1920s and 1930s, but use of this new technology was extremely limited.
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 ...
and
Ediphone Phonograph cylinders are the earliest commercial medium for recording and reproducing sound. Commonly known simply as "records" in their era of greatest popularity (c. 1896–1916), these hollow cylindrical objects have an audio recording engra ...
recorders, which still employed
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 ...
as the recording medium, were the devices normally used for these applications during this period. The peak of wire recording lasted from approximately 1946 to 1954. It resulted from technical improvements and the development of inexpensive designs licensed internationally by the Brush Development Company of Cleveland, Ohio and the Armour Research FoundationMorton (1998) (journal article), p. 213. of the Armour Institute of Technology (later the
IIT Research Institute IIT Research Institute (IITRI),Greenbaum & Wheeler (1967), cover sheet (technical paper).McCormac; et al. (1967), p. i (book)."IITRI" (or "iiTRi") is used on cover sheets of technical paper documents in prior decades. also known historically and ...
of the
Illinois Institute of Technology Illinois Institute of Technology (IIT) is a private research university in Chicago, Illinois. Tracing its history to 1890, the present name was adopted upon the merger of the Armour Institute and Lewis Institute in 1940. The university has prog ...
). The two organizations (Brush and Armour) licensed dozens of manufacturers in the U.S., Japan, and Europe. Examples are Wilcox-Gay, Peirce, Webcor, and Air King. Sales elsewhere encouraged
Sears Sears, Roebuck and Co. ( ), commonly known as Sears, is an American chain of department stores founded in 1892 by Richard Warren Sears and Alvah Curtis Roebuck and reincorporated in 1906 by Richard Sears and Julius Rosenwald, with what began a ...
to provide a model, and some authors to prepare specialized manuals. These improved wire recorders were not only marketed for office use, but also as home entertainment devices that offered advantages over the home acetate disc recorders which were increasingly sold for making short recordings of family and friends and for recording excerpts from radio broadcasts. Unlike home-cut phonograph records, the steel wire could be reused for new recordings and allowed much longer uninterrupted recordings to be made than the few minutes of audio per side possible with disc recorders. The earliest magnetic
tape recorder An audio tape recorder, also known as a tape deck, tape player or tape machine or simply a tape recorder, is a sound recording and reproduction device that records and plays back sounds usually using magnetic tape for storage. In its present ...
s, not commercially available in the United States until 1948, were too expensive, complicated, and bulky to compete with these consumer-level wire recorders.Morton (1998) (journal article). During the first half of the 1950s, however, tape recorders which were sufficiently affordable, simple, and compact to be suitable for home and office use started appearing and they rapidly superseded wire recorders in the marketplace. Exceptionally, the use of wire for
sound recording Sound recording and reproduction is the electrical, mechanical, electronic, or digital inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects. The two main classes of sound recording te ...
continued into the 1960s in Protona's Minifon miniature recorders, in which the importance of maximizing recording time in a minimum of space outweighed other considerations. For any given level of audio quality, the nearly hair-thin wire had the advantage that it was a much more compact storage medium than tape. The Minifon wire recorder was designed for stealth use and its accessories included a microphone disguised as a wristwatch. Wire recording was also used in some aircraft flight recorders beginning in the early 1940s, mainly for recording radio conversations between crewmen or with ground stations. Because steel wire was more compact, robust, and heat-resistant than magnetic tape (which is plastic-based), wire recorders continued to be manufactured for this purpose through the 1950s and remained in use somewhat later than that. There were also wire recorders made to record data in
satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ...
s and other unmanned spacecraft of the 1950s to perhaps the 1970s.


Characteristics


Magnetic format

Poulsen's original Telegraphone and other very early recorders placed the two poles of the record/replay head on opposite sides of the wire. The wire is thus magnetised transversely to the direction of travel. This method of magnetization was quickly found to have the limitation that as the wire twisted during playback, there were times when the magnetization of the wire was at right angles to the position of the two poles of the head and the output from the head fell to almost zero. The recorder was improved by placing the two poles on the same side of the wire so that the wire was magnetised along its length or longitudinally. Additionally, the poles were shaped into a "V" so that the head wrapped around the wire to some extent. This increased the magnetising effect and also increased the sensitivity of the head on replay because it collected more of the magnetic flux from the wire. This system was not entirely immune to twisting but the effects were far less marked.


Media capacity and speed

Compared to tape recorders, wire recording devices have a high media speed, made necessary because of the use of the solid metal medium. Standard postwar wire recorders use a nominal speed of 24 inches per second (610 mm/s), making a typical one-hour spool of wire 7,200 feet (approx. 2200 m) long. This enormous length is possible on a spool less than in diameter because the wire was very fine, having a diameter of for later models, an improvement over Poulsen's Telegraphone of 1898 which used wire. Smaller 30- and 15-minute lengths of wire were employed by the majority of recorders made after 1945. Some heavy-duty recorders use the larger Armour spools, which can contain enough wire to record continuously for several hours. Because the wire is pulled past the head by the take-up spool, the actual wire speed slowly increases as the effective diameter of the take-up spool increases. Standardization prevented this peculiarity from having any impact on the playback of a spool recorded on a different machine, but audible consequences can result from substantially altering the original length of a recorded wire by excisions or by dividing it up onto multiple spools.


Fidelity

The audio
fidelity Fidelity is the quality of faithfulness or loyalty. Its original meaning regarded duty in a broader sense than the related concept of ''fealty''. Both derive from the Latin word ''fidēlis'', meaning "faithful or loyal". In the City of London fin ...
of a wire recording made on one of these post-1945 machines is comparable to a contemporary phonograph record or one of the early tape recorders, given a microphone or other signal source of equal quality. Because of its homogeneous nature and very high speed, wire is relatively free of the noticeable background hiss which characterized tape recordings before the advent of noise reduction systems. The Magnecord Corp. of Chicago briefly manufactured a high-fidelity wire recorder intended for studio use, but soon abandoned the system to concentrate on tape recorders.


Handling and editing

To facilitate handling as the user threaded the wire across the recording head and affixed it to the take-up spool, some manufacturers attached a strip of plastic to each end of the wire. This was designed to press-fit snugly into either spool. To prevent the wire from piling up unevenly on the spool as it was recorded, played or rewound, on the majority of machines the head assembly slowly oscillates up and down or back and forth to distribute the wire evenly. On some machines, moving wire guides perform this function. These are similar to mechanisms that distribute line across a
fishing reel A fishing reel is a hand- cranked reel used in angling to wind and stow fishing line, typical mounted onto a fishing rod, but may also be used to retrieve a tethered arrow when bowfishing. Modern recreational fishing reels usually have fitting ...
. After recording or playback, the wire has to be rewound before any further use can be made of the machine. Unlike reel-to-reel tape recorders, the take-up reel on most wire recorders is not removable. A break in the wire is repaired by tying the ends together and trimming. When such a repair is made to an existing recording, a jump in the sound results during playback, but because of the high speed of the wire the loss of an inch due to tying and trimming is trivial and might pass unnoticed. Unfortunately, if the wire breaks it can easily become tangled, and snarls are extremely difficult to fix. Sometimes the only practical solution is to carefully cut the tangled portion away from the spool—an operation which runs the risk of endlessly enlarging the problem—and discard it. The difficulty of handling the wire itself when necessary is arguably the only serious shortcoming, among several definite advantages, of steel wire as a monophonic recording medium. Editing is accomplished by cutting and splicing. As the knot of each splice passes through the head during playback, a very brief loss of normal contact is inevitable and the resulting dropouts can make editing musical recordings problematic. Although wire is not as suitable for editing as magnetic tape (a plastic-based material) would prove to be, in the field of radio broadcasting it offered tremendous advantages over trying to edit material recorded on
transcription disc Electrical transcriptions are special phonograph recordings made exclusively for radio broadcasting,Browne, Ray B. and Browne, Pat, Eds. (2001). ''The Guide to United States Popular Culture''. The University of Wisconsin Press. . P. 263. which wer ...
s, which was usually accomplished by dubbing to a new transcription disc with the aid of multiple turntables and stopwatches. The first regularly scheduled network radio program produced and edited on wire was
CBS CBS Broadcasting Inc., commonly shortened to CBS, the abbreviation of its former legal name Columbia Broadcasting System, is an American commercial broadcast television and radio network serving as the flagship property of the CBS Entertainm ...
' ''
Hear It Now ''Hear It Now'', an American radio program on CBS, began on December 15, 1950, ending in June 1951. It was hosted by Edward R. Murrow and produced by Murrow and Fred W. Friendly. It ran for one hour on Fridays at 9 pm Eastern Time. The show's be ...
'' with
Edward R. Murrow Edward Roscoe Murrow (born Egbert Roscoe Murrow; April 25, 1908 – April 27, 1965) was an American broadcast journalist and war correspondent. He first gained prominence during World War II with a series of live radio broadcasts from Europe f ...
.


Notable uses

In 1944–1945, the 3132 Signal Service Company Special of the
U.S. Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cl ...
's top secret
Ghost Army The Ghost Army was a United States Army tactical deception unit during World War II officially known as the 23rd Headquarters Special Troops. The 1100-man unit was given a unique mission: to deceive Hitler's forces and mislead them as to the ...
used wire recorders to create
sonic deception Sonic deception refers to a deception tactic on the battlefield that involves the projection of sounds to produce noises intended to mislead hearers. The recorded noises target the enemy's sound-ranging equipment, as well as the human ear. It is ...
on the Western Front in the
Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. Multiple battlefield scenarios were recreated using military sounds recorded at
Fort Knox Fort Knox is a United States Army installation in Kentucky, south of Louisville and north of Elizabethtown. It is adjacent to the United States Bullion Depository, which is used to house a large portion of the United States' official gold res ...
,
Kentucky Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia to ...
. The wire-recorded audio, which was played back through powerful amplifiers and speakers mounted on vehicles, was used to conceal real
Allied An alliance is a relationship among people, groups, or states that have joined together for mutual benefit or to achieve some common purpose, whether or not explicit agreement has been worked out among them. Members of an alliance are called ...
deployments, locations and operations. In 1944 at the Middle East Radio Station of Cairo, Egyptian composer
Halim El-Dabh Halim Abdul Messieh El-Dabh ( ar, حليم عبد المسيح الضبع, ''Ḥalīm ʻAbd al-Masīḥ al-Ḍab''ʻ; March 4, 1921 – September 2, 2017) was an Egyptian-American composer, musician, ethnomusicologist, and educator, who had ...
used wire recorders as a tool to compose music. In 1946, David Boder, a professor of psychology at Illinois Institute of Technology in Chicago, traveled to Europe to record long interviews with "displaced persons"—most of them
Holocaust The Holocaust, also known as the Shoah, was the genocide of European Jews during World War II. Between 1941 and 1945, Nazi Germany and its collaborators systematically murdered some six million Jews across German-occupied Europe; a ...
survivors. Using an early wire recorder from the Armour Research Foundation, Boder came back with the first recorded Holocaust testimonials and in all likelihood the first recorded oral histories of significant length. In 1946,
Norman Corwin Norman Lewis Corwin (May 3, 1910 – October 18, 2011) was an American writer, screenwriter, producer, essayist and teacher of journalism and writing. His earliest and biggest successes were in the writing and directing of radio drama during the ...
and his technical assistant, Lee Bland, took a wire recorder on their One World Flight, a round-the-world trip subsidized by friends of
Wendell Willkie Wendell Lewis Willkie (born Lewis Wendell Willkie; February 18, 1892 – October 8, 1944) was an American lawyer, corporate executive and the 1940 Republican nominee for President. Willkie appealed to many convention delegates as the Republican ...
and patterned after Willkie's own 1942 trip. Corwin documented the post-war world and used his recordings in a series of 13 broadcast documentaries on CBS—which were also among the first broadcast uses of recorded sound allowed by the radio networks. In 1947,
Maya Deren Maya Deren (born Eleonora Derenkowska, uk, Елеоно́ра Деренко́вська, links=no;
, an American experimental filmmaker, purchased a wire recorder from her
Guggenheim Fellowship Guggenheim Fellowships are grants that have been awarded annually since by the John Simon Guggenheim Memorial Foundation to those "who have demonstrated exceptional capacity for productive scholarship or exceptional creative ability in the ar ...
funds to record Haitian Vodou ceremonies for her documentary: ''Meditation on Violence''. In 1949 at Fuld Hall in
Rutgers University Rutgers University (; RU), officially Rutgers, The State University of New Jersey, is a Public university, public land-grant research university consisting of four campuses in New Jersey. Chartered in 1766, Rutgers was originally called Queen's ...
, Paul Braverman made a 75-minute recording of a
Woody Guthrie Woodrow Wilson Guthrie (; July 14, 1912 – October 3, 1967) was an American singer-songwriter, one of the most significant figures in American folk music. His work focused on themes of American socialism and anti-fascism. He has inspired ...
concert using a wire recorder. The recording only came to light in 2001, and appears to be the only surviving live recording of Woody Guthrie; it was restored over several years and released on CD in 2007. The CD, '' The Live Wire: Woody Guthrie in Performance 1949'', subsequently won the 2008
Grammy Award for Best Historical Album The Grammy Award for Best Historical Album has been presented since 1979 and recognizes achievements in audio restoration. Since this category's creation, the award had several minor name changes: *In 1979 the award was known as Best Historical Re ...
. One of the world's first stored-program computers, SEAC, built in 1950 at the U.S.
National Bureau of Standards The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical sci ...
, used wire recorders to store digital data. In 1952, the
Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...
physics department's musical variety show ''The Physical Revue'', written by
Tom Lehrer Thomas Andrew Lehrer (; born April 9, 1928) is an American former musician, singer-songwriter, satirist, and mathematician, having lectured on mathematics and musical theater. He is best known for the pithy and humorous songs that he recorded in ...
and performed by a cast including Lehrer, Lewis M. Branscomb and others, was recorded on wire by a later winner of the
Nobel Prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
,
Norman Foster Ramsey Jr. Norman Foster Ramsey Jr. (August 27, 1915 – November 4, 2011) was an American physicist who was awarded the 1989 Nobel Prize in Physics, for the invention of the separated oscillatory field method, which had important applications in the const ...
This recording was recently rediscovered and made available online. Wire recorders sometimes appear in motion pictures made during the time of their widest use. For example, in office scenes in the original 1951 version of '' The Thing'', a typical
Webster-Chicago The Webster Chicago Corporation was a maker of electronic equipment in Chicago, Illinois. Many products were sold under the brand name Webcor. The product line included record changers, wire recorders and reel to reel tape recorders. They also ...
unit is plainly visible on a small table by the window. In some shots (e.g., at 0:11:40 on the 2003 DVD release), its detached lid, carrying two extra spools of wire, is also visible. In this instance the recorder is simply "set dressing" and is not shown in operation.
Ann Robinson Ann Robinson (born May 25, 1929) is a former American actress and stunt horse rider, perhaps best known for her work in the science-fiction classic ''The War of the Worlds'' (1953) and in the 1954 film '' Dragnet'', in which she starred as a L ...
's character in the 1954 '' Dragnet'' feature film carried and used a Protona Minifon wire recorder to gather evidence in a pivotal scene.
Jack Webb John Randolph Webb (April 2, 1920 – December 23, 1982) was an American actor, television producer, Television director, director, and screenwriter, who is most famous for his role as Joe Friday, Sgt. Joe Friday in the Dragnet (franchise) ...
(1954).
Dragnet (1954 film) ''Dragnet'' is a 1954 American crime film directed by Jack Webb and written by Richard L. Breen. The film stars Webb, Ben Alexander, Richard Boone, Ann Robinson, Stacy Harris, Virginia Gregg and Vic Perrin. The film was adapted from the radi ...
. Los Angeles: Warner Bros.
The 1958 spy thriller ''Spy in the Sky!'' uses a wire recording as a plot device. In the episode "The Relaxed Informer" (S1E24) of ''
Danger Man ''Danger Man'' (retitled ''Secret Agent'' in the United States for the revived series, and ''Destination Danger'' and ''John Drake'' in other overseas markets) is a British television series that was broadcast between 1960 and 1962, and again b ...
'' the spy courier is smuggling a recording made on wire secreted inside the handle holding a puppet's strings. The recording wire is later shown being played in an office using a wire player. In episode 2.18 of '' Adventures of Superman'', "Semi-Private Eye", PI Homer Garrity has a wire recorder he uses to surreptitiously record his clients. The fictional Allied officers of '' Hogan's Heroes'' used a wire recorder to record a meeting in Kommandant Klink's office on a device that was disguised as a sewing box made of wooden thread spools. A wire recording was the subject of a 1966 ''
Mission Impossible ''Mission: Impossible'' is a multimedia franchise based on a fictional secret espionage agency known as the Impossible Missions Force (IMF). The 1966 TV series ran for seven seasons and was revived in 1988 for two seasons. It inspired a serie ...
'' episode titled " A Spool There Was". The '' Department S'' episode "A Cellar Full of Silence" revolves around a blackmail recording on a wire disguised as part of another object. A wire recorder is also used as a plot device in
Arthur Miller Arthur Asher Miller (October 17, 1915 – February 10, 2005) was an American playwright, essayist and screenwriter in the 20th-century American theater. Among his most popular plays are '' All My Sons'' (1947), ''Death of a Salesman'' ( ...
's 1949 play, ''
Death of a Salesman ''Death of a Salesman'' is a 1949 stage play written by American playwright Arthur Miller. The play premiered on Broadway in February 1949, running for 742 performances. It is a two-act tragedy set in late 1940s Brooklyn told through a montag ...
''. Similarly, in the 1990 film '' Dick Tracy'', set in the 1930s, Warren Beatty, in the title role, is shown manipulating a wire on which the voice of "Mumbles" (played by Dustin Hoffman) is recorded, in order to decipher the otherwise unintelligible speech of the fictitious criminal. In the 1990 film ''
The Two Jakes ''The Two Jakes'' is a 1990 American neo-noir mystery crime drama film and the sequel to the 1974 film ''Chinatown''. Directed by and starring Jack Nicholson, it also features Harvey Keitel, Meg Tilly, Madeleine Stowe, Richard Farnsworth, Fre ...
'', set in 1948, the plot centers around a wire recording made in a divorce-case-turned-homicide. In
Bones_(TV_series) ''Bones'' is an American crime procedural comedy-drama television series created by Hart Hanson for Fox. It premiered on September 13, 2005, and concluded on March 28, 2017, airing for 246 episodes over 12 seasons. The show is based on forensi ...
Series 10, Episode 2, "The Lance to the Heart", an old wire recording of
JFK John Fitzgerald Kennedy (May 29, 1917 – November 22, 1963), often referred to by his initials JFK and the nickname Jack, was an American politician who served as the 35th president of the United States from 1961 until his assassination i ...
is found in the house of a former agent of
J. Edgar Hoover John Edgar Hoover (January 1, 1895 – May 2, 1972) was an American law enforcement administrator who served as the first Director of the Federal Bureau of Investigation (FBI). He was appointed director of the Bureau of Investigation  ...
.


See also

* Oberlin Smith *
Webster-Chicago The Webster Chicago Corporation was a maker of electronic equipment in Chicago, Illinois. Many products were sold under the brand name Webcor. The product line included record changers, wire recorders and reel to reel tape recorders. They also ...


References


Further reading

* Bannerman, R. LeRoy (1986) (book), ''On A Note of Triumph: Norman Corwin and the Golden Years of Radio''. University of Alabama Press. * Hickman, Reginald Elwick Beatty (1958) (book), ''Magnetic Recording Handbook: Theory, practice and servicing of domestic and professional tape and wire recorders'', hardcover, 176 pp., 2nd edition; George Newnes (publisher), London, England lso later edition, 1962 * Sams, Howard W. (1947) (book), ''Automatic Record Changer Service Manual: Including Wire, Ribbon, Tape and Paper Disc Recorders'', hardcover, 1st edition (1947); Sams, Indianapolis. * Ehrlich, Matthew C. (2006) (journal article), "A Pathfinding Radio Documentary Series: Norman Corwin's ''One World Flight'', ''American Journalism'', 23(4):35–59, 2006. . * * * Judge, G. R. (1950) (manual), ''Wire Recorder Manual'', Bernards Radio Manuals No. 88, softcover (cardstock covers), 48 pp.; Bernards Publishers Ltd., London, 1950. * Sears Roebuck Co. (c. 1949) (pamphlet manual), ''Parts List and Instructions for Installing & Operating Your Silvertone Superheterodyne Radio Receiver with Wire Recorder'', softcover, 14 pp., Sears Roebuck Co., circa 1949.


External links

* {{DEFAULTSORT:Wire Recording Audiovisual introductions in 1898 Audio storage Discontinued media formats Tape recording