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21 Berliner, Emile
SUBJECT AREA: Recording[br]b. 20 May 1851 Hannover, Germanyd. 3 August 1929 Montreal, Canada[br]German (naturalized American) inventor, developer of the disc record and lateral mechanical replay.[br]After arriving in the USA in 1870 and becoming an American citizen, Berliner worked as a dry-goods clerk in Washington, DC, and for a period studied electricity at Cooper Union for the Advancement of Science and Art, New York. He invented an improved microphone and set up his own experimental laboratory in Washington, DC. He developed a microphone for telephone use and sold the rights to the Bell Telephone Company. Subsequently he was put in charge of their laboratory, remaining in that position for eight years. In 1881 Berliner, with his brothers Joseph and Jacob, founded the J.Berliner Telephonfabrik in Hanover, the first factory in Europe specializing in telephone equipment.Inspired by the development work performed by T.A. Edison and in the Volta Laboratory (see C.S. Tainter), he analysed the existing processes for recording and reproducing sound and in 1887 developed a process for transferring lateral undulations scratched in soot into an etched groove that would make a needle and diaphragm vibrate. Using what may be regarded as a combination of the Phonautograph of Léon Scott de Martinville and the photo-engraving suggested by Charles Cros, in May 1887 he thus demonstrated the practicability of the laterally recorded groove. He termed the apparatus "Gramophone". In November 1887 he applied the principle to a glass disc and obtained an inwardly spiralling, modulated groove in copper and zinc. In March 1888 he took the radical step of scratching the lateral vibrations directly onto a rotating zinc disc, the surface of which was protected, and the subsequent etching created the groove. Using well-known principles of printing-plate manufacture, he developed processes for duplication by making a negative mould from which positive copies could be pressed in a thermoplastic compound. Toy gramophones were manufactured in Germany from 1889 and from 1892–3 Berliner manufactured both records and gramophones in the USA. The gramophones were hand-cranked at first, but from 1896 were based on a new design by E.R. Johnson. In 1897–8 Berliner spread his activities to England and Germany, setting up a European pressing plant in the telephone factory in Hanover, and in 1899 a Canadian company was formed. Various court cases over patents removed Berliner from direct running of the reconstructed companies, but he retained a major economic interest in E.R. Johnson's Victor Talking Machine Company. In later years Berliner became interested in aeronautics, in particular the autogiro principle. Applied acoustics was a continued interest, and a tile for controlling the acoustics of large halls was successfully developed in the 1920s.[br]Bibliography16 May 1888, Journal of the Franklin Institute 125 (6) (Lecture of 16 May 1888) (Berliner's early appreciation of his own work).1914, Three Addresses, privately printed (a history of sound recording). US patent no. 372,786 (basic photo-engraving principle).US patent no. 382,790 (scratching and etching).US patent no. 534,543 (hand-cranked gramophone).Further ReadingR.Gelatt, 1977, The Fabulous Phonograph, London: Cassell (a well-researched history of reproducible sound which places Berliner's contribution in its correct perspective). J.R.Smart, 1985, "Emile Berliner and nineteenth-century disc recordings", in WonderfulInventions, ed. Iris Newson, Washington, DC: Library of Congress, pp. 346–59 (provides a reliable account).O.Read and W.L.Welch, 1959, From Tin Foil to Stereo, Indianapolis: Howard W.Sams, pp. 119–35 (provides a vivid account, albeit with less precision).GB-N -
22 De Forest, Lee
SUBJECT AREA: Broadcasting, Electronics and information technology, Photography, film and optics, Recording, Telecommunications[br]b. 26 August 1873 Council Bluffs, Iowa, USAd. 30 June 1961 Hollywood, California, USA[br]American electrical engineer and inventor principally known for his invention of the Audion, or triode, vacuum tube; also a pioneer of sound in the cinema.[br]De Forest was born into the family of a Congregational minister that moved to Alabama in 1879 when the father became President of a college for African-Americans; this was a position that led to the family's social ostracism by the white community. By the time he was 13 years old, De Forest was already a keen mechanical inventor, and in 1893, rejecting his father's plan for him to become a clergyman, he entered the Sheffield Scientific School of Yale University. Following his first degree, he went on to study the propagation of electromagnetic waves, gaining a PhD in physics in 1899 for his thesis on the "Reflection of Hertzian Waves from the Ends of Parallel Wires", probably the first US thesis in the field of radio.He then joined the Western Electric Company in Chicago where he helped develop the infant technology of wireless, working his way up from a modest post in the production area to a position in the experimental laboratory. There, working alone after normal working hours, he developed a detector of electromagnetic waves based on an electrolytic device similar to that already invented by Fleming in England. Recognizing his talents, a number of financial backers enabled him to set up his own business in 1902 under the name of De Forest Wireless Telegraphy Company; he was soon demonstrating wireless telegraphy to interested parties and entering into competition with the American Marconi Company.Despite the failure of this company because of fraud by his partners, he continued his experiments; in 1907, by adding a third electrode, a wire mesh, between the anode and cathode of the thermionic diode invented by Fleming in 1904, he was able to produce the amplifying device now known as the triode valve and achieve a sensitivity of radio-signal reception much greater than possible with the passive carborundum and electrolytic detectors hitherto available. Patented under the name Audion, this new vacuum device was soon successfully used for experimental broadcasts of music and speech in New York and Paris. The invention of the Audion has been described as the beginning of the electronic era. Although much development work was required before its full potential was realized, the Audion opened the way to progress in all areas of sound transmission, recording and reproduction. The patent was challenged by Fleming and it was not until 1943 that De Forest's claim was finally recognized.Overcoming the near failure of his new company, the De Forest Radio Telephone Company, as well as unsuccessful charges of fraudulent promotion of the Audion, he continued to exploit the potential of his invention. By 1912 he had used transformer-coupling of several Audion stages to achieve high gain at radio frequencies, making long-distance communication a practical proposition, and had applied positive feedback from the Audion output anode to its input grid to realize a stable transmitter oscillator and modulator. These successes led to prolonged patent litigation with Edwin Armstrong and others, and he eventually sold the manufacturing rights, in retrospect often for a pittance.During the early 1920s De Forest began a fruitful association with T.W.Case, who for around ten years had been working to perfect a moving-picture sound system. De Forest claimed to have had an interest in sound films as early as 1900, and Case now began to supply him with photoelectric cells and primitive sound cameras. He eventually devised a variable-density sound-on-film system utilizing a glow-discharge modulator, the Photion. By 1926 De Forest's Phonofilm had been successfully demonstrated in over fifty theatres and this system became the basis of Movietone. Though his ideas were on the right lines, the technology was insufficiently developed and it was left to others to produce a system acceptable to the film industry. However, De Forest had played a key role in transforming the nature of the film industry; within a space of five years the production of silent films had all but ceased.In the following decade De Forest applied the Audion to the development of medical diathermy. Finally, after spending most of his working life as an independent inventor and entrepreneur, he worked for a time during the Second World War at the Bell Telephone Laboratories on military applications of electronics.[br]Principal Honours and DistinctionsInstitute of Electronic and Radio Engineers Medal of Honour 1922. President, Institute of Electronic and Radio Engineers 1930. Institute of Electrical and Electronics Engineers Edison Medal 1946.Bibliography1904, "Electrolytic detectors", Electrician 54:94 (describes the electrolytic detector). 1907, US patent no. 841,387 (the Audion).1950, Father of Radio, Chicago: WIlcox \& Follett (autobiography).De Forest gave his own account of the development of his sound-on-film system in a series of articles: 1923. "The Phonofilm", Transactions of the Society of Motion Picture Engineers 16 (May): 61–75; 1924. "Phonofilm progress", Transactions of the Society of Motion Picture Engineers 20:17–19; 1927, "Recent developments in the Phonofilm", Transactions of the Society of Motion Picture Engineers 27:64–76; 1941, "Pioneering in talking pictures", Journal of the Society of Motion Picture Engineers 36 (January): 41–9.Further ReadingG.Carneal, 1930, A Conqueror of Space (biography).I.Levine, 1964, Electronics Pioneer, Lee De Forest (biography).E.I.Sponable, 1947, "Historical development of sound films", Journal of the Society of Motion Picture Engineers 48 (April): 275–303 (an authoritative account of De Forest's sound-film work, by Case's assistant).W.R.McLaurin, 1949, Invention and Innovation in the Radio Industry.C.F.Booth, 1955, "Fleming and De Forest. An appreciation", in Thermionic Valves 1904– 1954, IEE.V.J.Phillips, 1980, Early Radio Detectors, London: Peter Peregrinus.KF / JW
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