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1 Marconi, Marchese Guglielmo
[br]b. 25 April 1874 Bologna, Italyd. 20 July 1937 Rome, Italy[br]Italian radio pioneer whose inventiveness and business skills made radio communication a practical proposition.[br]Marconi was educated in physics at Leghorn and at Bologna University. An avid experimenter, he worked in his parents' attic and, almost certainly aware of the recent work of Hertz and others, soon improved the performance of coherers and spark-gap transmitters. He also discovered for himself the use of earthing and of elevated metal plates as aerials. In 1895 he succeeded in transmitting telegraphy over a distance of 2 km (1¼ miles), but the Italian Telegraph authority rejected his invention, so in 1896 he moved to England, where he filed the first of many patents. There he gained the support of the Chief Engineer of the Post Office, and by the following year he had achieved communication across the Bristol Channel.The British Post Office was also slow to take up his work, so in 1897 he formed the Wireless Telegraph \& Signal Company to work independently. In 1898 he sold some equipment to the British Army for use in the Boer War and established the first permanent radio link from the Isle of Wight to the mainland. In 1899 he achieved communication across the English Channel (a distance of more than 31 miles or 50 km), the construction of a wireless station at Spezia, Italy, and the equipping of two US ships to report progress in the America's Cup yacht race, a venture that led to the formation of the American Marconi Company. In 1900 he won a contract from the British Admiralty to sell equipment and to train operators. Realizing that his business would be much more successful if he could offer his customers a complete radio-communication service (known today as a "turnkey" deal), he floated a new company, the Marconi International Marine Communications Company, while the old company became the Marconi Wireless Telegraph Company.His greatest achievement occurred on 12 December 1901, when Morse telegraph signals from a transmitter at Poldhu in Cornwall were received at St John's, Newfoundland, a distance of some 2,100 miles (3,400 km), with the use of an aerial flown by a kite. As a result of this, Marconi's business prospered and he became internationally famous, receiving many honours for his endeavours, including the Nobel Prize for Physics in 1909. In 1904, radio was first used to provide a daily bulletin at sea, and in 1907 a transatlantic wireless telegraphy service was inaugurated. The rescue of 1,650 passengers from the shipwreck of SS Republic in 1909 was the first of many occasions when wireless was instrumental in saving lives at sea, most notable being those from the Titanic on its maiden voyage in April 1912; more lives would have been saved had there been sufficient lifeboats. Marconi was one of those who subsequently pressed for greater safety at sea. In 1910 he demonstrated the reception of long (8 km or 5 miles) waves from Ireland in Buenos Aires, but after the First World War he began to develop the use of short waves, which were more effectively reflected by the ionosphere. By 1918 the first link between England and Australia had been established, and in 1924 he was awarded a Post Office contract for short-wave communication between England and the various parts of the British Empire.With his achievements by then recognized by the Italian Government, in 1915 he was appointed Radio-Communications Adviser to the Italian armed forces, and in 1919 he was an Italian delegate to the Paris Peace Conference. From 1921 he lived on his yacht, the Elettra, and although he joined the Fascist Party in 1923, he later had reservations about Mussolini.[br]Principal Honours and DistinctionsNobel Prize for Physics (jointly with K.F. Braun) 1909. Russian Order of S t Anne. Commander of St Maurice and St Lazarus. Grand Cross of the Order of the Crown (i.e. Knight) of Italy 1902. Freedom of Rome 1903. Honorary DSc Oxford. Honorary LLD Glasgow. Chevalier of the Civil Order of Savoy 1905. Royal Society of Arts Albert Medal. Honorary knighthood (GCVO) 1914. Institute of Electrical and Electronics Engineers Medal of Honour 1920. Chairman, Royal Society of Arts 1924. Created Marquis (Marchese) 1929. Nominated to the Italian Senate 1929. President, Italian Academy 1930. Rector, University of St Andrews, Scotland, 1934.Bibliography1896, "Improvements in transmitting electrical impulses and in apparatus thereof", British patent no. 12,039.1 June 1898, British patent no. 12,326 (transformer or "jigger" resonant circuit).1901, British patent no. 7,777 (selective tuning).1904, British patent no. 763,772 ("four circuit" tuning arrangement).Further ReadingD.Marconi, 1962, My Father, Marconi.W.J.Baker, 1970, A History of the Marconi Company, London: Methuen.KFBiographical history of technology > Marconi, Marchese Guglielmo
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2 Braun, Karl Ferdinand
[br]b. 6 June 1850 Fulda, Hesse, Germanyd. 20 April 1918 New York City, New York, USA[br]German physicist who shared with Marconi the 1909 Nobel Prize for Physics for developments in wireless telegraphy; inventor of the cathode ray oscilloscope.[br]After obtaining degrees from the universities of Marburg and Berlin (PhD) and spending a short time as Headmaster of the Thomas School in Berlin, Braun successively held professorships in theoretical physics at the universities of Marburg (1876), Strasbourg (1880) and Karlsruhe (1883) before becoming Professor of Experimental Physics at Tübingen in 1885 and Director and Professor of Physics at Strasbourg in 1895.During this time he devised experimental apparatus to determine the dielectric constant of rock salt and developed the Braun high-tension electrometer. He also discovered that certain mineral sulphide crystals would only conduct electricity in one direction, a rectification effect that made it possible to detect and demodulate radio signals in a more reliable manner than was possible with the coherer. Primarily, however, he was concerned with improving Marconi's radio transmitter to increase its broadcasting range. By using a transmitter circuit comprising a capacitor and a spark-gap, coupled to an aerial without a spark-gap, he was able to obtain much greater oscillatory currents in the latter, and by tuning the transmitter so that the oscillations occupied only a narrow frequency band he reduced the interference with other transmitters. Other achievements include the development of a directional aerial and the first practical wavemeter, and the measurement in Strasbourg of the strength of radio waves received from the Eiffel Tower transmitter in Paris. For all this work he subsequently shared with Marconi the 1909 Nobel Prize for Physics.Around 1895 he carried out experiments using a torsion balance in order to measure the universal gravitational constant, g, but the work for which he is probably best known is the addition of deflecting plates and a fluorescent screen to the Crooke's tube in 1897 in order to study the characteristics of high-frequency currents. The oscilloscope, as it was called, was not only the basis of a now widely used and highly versatile test instrument but was the forerunner of the cathode ray tube, or CRT, used for the display of radar and television images.At the beginning of the First World War, while in New York to testify in a patent suit, he was trapped by the entry of the USA into the war and remained in Brooklyn with his son until his death.[br]Principal Honours and DistinctionsNobel Prize for Physics (jointly with Marconi) 1909.Bibliography1874, "Assymetrical conduction of certain metal sulphides", Pogg. Annal. 153:556 (provides an account of the discovery of the crystal rectifier).1897, "On a method for the demonstration and study of currents varying with time", Wiedemann's Annalen 60:552 (his description of the cathode ray oscilloscope as a measuring tool).Further ReadingK.Schlesinger \& E.G.Ramberg, 1962, "Beamdeflection and photo-devices", Proceedings of the Institute of Radio Engineers 50, 991.KF -
3 Popov, Aleksandr Stepanovich
[br]b. 16 March 1859 Bogoslavsky, Zamod, Ural District, Russiad. 13 January 1906 St Petersburg, Russia[br]Russian physicist and electrical engineer acclaimed by the former Soviet Union as the inventor of radio.[br]Popov, the son of a village priest, received his early education in a seminary, but in 1877 he entered the University of St Petersburg to study mathematics. He graduated with distinction in 1883 and joined the faculty to teach mathematics and physics. Then, increasingly interested in electrical engineering, he became an instructor at the Russian Navy Torpedo School at Krondstadt, near St Petersburg, where he later became a professor. On 7 May 1895 he is said to have transmitted and received Morse code radio signals over a distance of 40 m (130 ft) in a demonstration given at St Petersburg University to the Russian Chemical Society, but in a paper published in January 1896 in the Journal of the Russian Physical and Chemical Society, he in fact described the use of a coherer for recording atmospheric disturbances such as lightning, together with the design of a modified coherer intended for reception at a distance of 5 km (3 miles). Subsequently, on 26 November 1897, after Marconi's own radio-transmission experiments had been publicized, he wrote a letter claiming priority for his discovery to the English-language journal Electrician, in the form of a translated précis of his original paper, but neither the original Russian paper nor the English précis made specific claims of either a receiver or a transmitter as such. However, by 1898 he had certainly developed some form of ship-to-shore radio for the Russian Navy. In 1945, long after the Russian revolution, the communist regime supported his claim to be the inventor of radio, but this is a matter for much debate and the priority of Marconi's claim is generally acknowledged outside the USSR.[br]Bibliography1896, Journal of the Russian Physical and Chemical Society (his original paper in Russian).1897, Electrician 40:235 (the English précis).Further ReadingC.Susskind, 1962, "Popov and the beginnings of radio telegraphy", Proceedings of the Institute of Radio Engineers 50:2,036.——1964, Marconi, Popov and the dawn of radiocommunication', Electronics and Power, London: Institution of Electrical Engineers, 10:76.KFBiographical history of technology > Popov, Aleksandr Stepanovich
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4 Sarnoff, David
[br]b. 27 February 1891 Uzlian, Minsk (now in Belarus)d. 12 December 1971 New York City, New York, USA[br]Russian/American engineer who made a major contribution to the commercial development of radio and television.[br]As a Jewish boy in Russia, Sarnoff spent several years preparing to be a Talmudic Scholar, but in 1900 the family emigrated to the USA and settled in Albany, New York. While at public school and at the Pratt Institute in Brooklyn, New York, he helped the family finances by running errands, selling newspapers and singing the liturgy in the synagogue. After a short period as a messenger boy with the Commercial Cable Company, in 1906 he became an office boy with the Marconi Wireless Telegraph Company of America (see G. Marconi). Having bought a telegraph instrument with his first earnings, he taught himself Morse code and was made a junior telegraph operator in 1907. The following year he became a wireless operator at Nantucket Island, then in 1909 he became Manager of the Marconi station at Sea Gate, New York. After two years at sea he returned to a shore job as wireless operator at the world's most powerful station at Wanamaker's store in Manhattan. There, on 14 April 1912, he picked up the distress signals from the sinking iner Titanic, remaining at his post for three days.Rewarded by rapid promotion (Chief Radio Inspector 1913, Contract Manager 1914, Assistant Traffic Manager 1915, Commercial Manager 1917) he proposed the introduction of commercial radio broadcasting, but this received little response. Consequently, in 1919 he took the job of Commercial Manager of the newly formed Radio Corporation of America (RCA), becoming General Manager in 1921, Vice- President in 1922, Executive Vice-President in 1929 and President in 1930. In 1921 he was responsible for the broadcasting of the Dempsey-Carpentier title-fight, as a result of which RCA sold $80 million worth of radio receivers in the following three years. In 1926 he formed the National Broadcasting Company (NBC). Rightly anticipating the development of television, in 1928 he inaugurated an experimental NBC television station and in 1939 demonstrated television at the New York World Fair. Because of his involvement with the provision of radio equipment for the armed services, he was made a lieutenant-colonel in the US Signal Corps Reserves in 1924, a full colonel in 1931 and, while serving as a communications consultant to General Eisenhower during the Second World War, Brigadier General in 1944.With the end of the war, RCA became a major manufacturer of television receivers and then invested greatly in the ultimately successful development of shadowmask tubes and receivers for colour television. Chairman and Chief Executive from 1934, Sarnoff held the former post until his retirement in 1970.[br]Principal Honours and DistinctionsFrench Croix de Chevalier d'honneur 1935, Croix d'Officier 1940, Croix de Commandant 1947. Luxembourg Order of the Oaken Crown 1960. Japanese Order of the Rising Sun 1960. US Legion of Merit 1946. UN Citation 1949. French Union of Inventors Gold Medal 1954.KFSee also: Zworykin, Vladimir Kosma -
5 Shoenberg, Isaac
[br]b. 1 March 1880 Kiev, Ukrained. 25 January 1963 Willesden, London, England[br]Russian engineer and friend of Vladimir Zworykin; Director of Research at EMI, responsible for creating the team that successfully developed the world's first all-electronic television system.[br]After his initial engineering education at Kiev Polytechnic, Shoenberg went to London to undertake further studies at the Royal College of Science. In 1905 he returned to Russia and rose to become Chief Engineer of the Russian Wireless Telegraphy Company. He then returned to England, where he was a consultant in charge of the Patent Department and then joint General Manager of the Marconi Wireless Telegraphy Company (see Marconi). In 1929 he joined the Columbia Graphophone Company, but two years later this amalgamated with the Gramophone Company, by then known as His Master's voice (HMV), to form EMI (Electric and Musical Industries), a company in which the Radio Corporation of America (RCA) had a significant shareholding. Appointed Director of the new company's Research Laboratories in 1931, Shoenberg gathered together a team of highly skilled engineers, including Blumlein, Browne, Willans, McGee, Lubszynski, Broadway and White, with the objective of producing an all-electronic television system suitable for public broadcasting. A 150-line system had already been demonstrated using film as the source material; a photoemissive camera tube similar to Zworykin's iconoscope soon followed. With alternate demonstrations of the EMI system and the mechanical system of Baird arranged with the object of selecting a broadcast system for the UK, Shoenberg took the bold decision to aim for a 405-line "high-definition" standard, using interlaced scanning based on an RCA patent and further developed by Blumlein. This was so successful that it was formally adopted as the British standard in 1935 and regular broadcasts, the first in the world, began in 1937. It is a tribute to Shoenberg's vision and the skills of his team that this standard was to remain in use, apart from the war years, until finally superseded in 1985.[br]Principal Honours and DistinctionsKnighted 1954. Institution of Electrical Engineers Faraday Medal 1954.Further ReadingA.D.Blumlein et al., 1938, "The Marconi-EMI television system", Journal of the Institution of Electrical Engineers 83:729 (provides a description of the development of the 405-line system).For more background information, see Proceedings of the International Conference on the History of Television. From Early Days to the Present, November 1986, Institution of Electrical Engineers Publication No. 271.KF -
6 Cockerell, Christopher Sydney
[br]b. 4 June 1910 Cambridge, England[br]British designer and engineer who invented the hovercraft.[br]He was educated at Gresham's School in Holt and at Peterhouse College, Cambridge, where he graduated in engineering in 1931; he was made an Honorary Fellow in 1974. Cockerell entered the engineering firm of W.H.Allen \& Sons of Bedford as a pupil in 1931, and two years later he returned to Cambridge to engage in radio research for a further two years. In 1935 he joined Marconi Wireless Telegraph Company, working on very high frequency (VHF) transmitters and direction finders. During the Second World War he worked on airborne navigation and communication equipment, and later he worked on radar. During this period he filed thirty six patents in the fields of radio and navigational systems.In 1950 Cockerell left Marconi to set up his own boat-hire business on the Norfolk Broads. He began to consider how to increase the speed of boats by means of air lubrication. Since the 1870s engineers had at times sought to reduce the drag on a boat by means of a thin layer of air between hull and water. After his first experiments, Cockerell concluded that a significant reduction in drag could only be achieved with a thick cushion of air. After experimenting with several ways of applying the air-cushion principle, the first true hovercraft "took off" in 1955. It was a model in balsa wood, 2 ft 6 in. (762 mm) long and weighing 4½ oz. (27.6 g); it was powered by a model-aircraft petrol engine and could travel over land or water at 13 mph (20.8 km/h). Cockerell filed his first hovercraft patent on 12 December 1955. The following year he founded Hovercraft Ltd and began the search for a manufacturer. The government was impressed with the invention's military possibilities and placed it on the secret list. The secret leaked out, however, and the project was declassified. In 1958 the National Research and Development Corporation decided to give its backing, and the following year Saunders Roe Ltd with experience of making flying boats, produced the epoch-making SR N1, a hovercraft with an air cushion produced by air jets directed downwards and inwards arranged round the periphery of the craft. It made a successful crossing of the English Channel, with the inventor on board.Meanwhile Cockerell had modified the hovercraft so that the air cushion was enclosed within flexible skirts. In this form it was taken up by manufacturers throughout the world and found wide application as a passenger-carrying vehicle, for military transport and in scientific exploration and survey work. The hover principle found other uses, such as for air-beds to relieve severely burned patients and for hover mowers.The development of the hovercraft has occupied Cockerell since then and he has been actively involved in the several companies set up to exploit the invention, including Hovercraft Development Ltd and British Hovercraft Corporation. In the 1970s and 1980s he took up the idea of the generation of electricity by wavepower; he was Founder of Wavepower Ltd, of which he was Chairman from 1974 to 1982.[br]Principal Honours find DistinctionsKnighted 1969. CBE 1955. FRS 1967.LRDBiographical history of technology > Cockerell, Christopher Sydney
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7 Poulsen, Valdemar
[br]b. 23 November 1869 Copenhagen, Denmarkd. 23 July 1942 Gentofte, Denmark[br]Danish engineer who developed practical magnetic recording and the arc generator for continuous radio waves.[br]From an early age he was absorbed by phenomena of physics to the exclusion of all other subjects, including mathematics. When choosing his subjects for the final three years in Borgedydskolen in Christianshavn (Copenhagen) before university, he opted for languages and history. At the University of Copenhagen he embarked on the study of medicine in 1889, but broke it off and was apprenticed to the machine firm of A/S Frichs Eftf. in Aarhus. He was employed between 1893 and 1899 as a mechanic and assistant in the laboratory of the Copenhagen Telephone Company KTAS. Eventually he advanced to be Head of the line fault department. This suited his desire for experiment and measurement perfectly. After the invention of the telegraphone in 1898, he left the laboratory and with responsible business people he created Aktieselskabet Telegrafonen, Patent Poulsen in order to develop it further, together with Peder Oluf Pedersen (1874– 1941). Pedersen brought with him the mathematical background which eventually led to his professorship in electronic engineering in 1922.The telegraphone was the basis for multinational industrial endeavours after it was demonstrated at the 1900 World's Exhibition in Paris. It must be said that its strength was also its weakness, because the telegraphone was unique in bringing sound recording and reproduction to the telephone field, but the lack of electronic amplifiers delayed its use outside this and the dictation fields (where headphones could be used) until the 1920s. However, commercial interest was great enough to provoke a number of court cases concerning patent infringement, in which Poulsen frequently figured as a witness.In 1903–4 Poulsen and Pedersen developed the arc generator for continuous radio waves which was used worldwide for radio transmitters in competition with Marconi's spark-generating system. The inspiration for this work came from the research by William Duddell on the musical arc. Whereas Duddell had proposed the use of the oscillations generated in his electric arc for telegraphy in his 1901 UK patent, Poulsen contributed a chamber of hydrogen and a transverse magnetic field which increased the efficiency remarkably. He filed patent applications on these constructions from 1902 and the first publication in a scientific forum took place at the International Electrical Congress in St Louis, Missouri, in 1904.In order to use continuous waves efficiently (the high frequency constituted a carrier), Poulsen developed both a modulator for telegraphy and a detector for the carrier wave. The modulator was such that even the more primitive spark-communication receivers could be used. Later Poulsen and Pedersen developed frequency-shift keying.The Amalgamated Radio-Telegraph Company Ltd was launched in London in 1906, combining the developments of Poulsen and those of De Forest Wireless Telegraph Syndicate. Poulsen contributed his English and American patents. When this company was liquidated in 1908, its assets were taken over by Det Kontinentale Syndikat for Poulsen Radio Telegrafi, A/S in Copenhagen (liquidated 1930–1). Some of the patents had been sold to C.Lorenz AG in Berlin, which was very active.The arc transmitting system was in use worldwide from about 1910 to 1925, and the power increased from 12 kW to 1,000 kW. In 1921 an exceptional transmitter rated at 1,800 kW was erected on Java for communications with the Netherlands. More than one thousand installations had been in use worldwide. The competing systems were initially spark transmitters (Marconi) and later rotary converters ( Westinghouse). Similar power was available from valve transmitters only much later.From c. 1912 Poulsen did not contribute actively to further development. He led a life as a well-respected engineer and scientist and served on several committees. He had his private laboratory and made experiments in the composition of matter and certain resonance phenomena; however, nothing was published. It has recently been suggested that Poulsen could not have been unaware of Oberlin Smith's work and publication in 1888, but his extreme honesty in technical matters indicates that his development was indeed independent. In the case of the arc generator, Poulsen was always extremely frank about the inspiration he gained from earlier developers' work.[br]Bibliography1899, British patent no. 8,961 (the first British telegraphone patent). 1903, British patent no. 15,599 (the first British arc-genera tor patent).His scientific publications are few, but fundamental accounts of his contribution are: 1900, "Das Telegraphon", Ann. d. Physik 3:754–60; 1904, "System for producing continuous oscillations", Trans. Int. El. Congr. St. Louis, Vol. II, pp. 963–71.Further ReadingA.Larsen, 1950, Telegrafonen og den Traadløse, Ingeniørvidenskabelige Skrifter no. 2, Copenhagen (provides a very complete, although somewhat confusing, account of Poulsen's contributions; a list of his patents is given on pp. 285–93).F.K.Engel, 1990, Documents on the Invention of Magnetic Re cor ding in 1878, New York: Audio Engineering Society, reprint no. 2,914 (G2) (it is here that doubt is expressed about whether Poulsen's ideas were developed independently).GB-N -
8 Preece, Sir William Henry
[br]b. 15 February 1834 Bryn Helen, Gwynedd, Walesd. 6 November 1913 Penrhos, Gwynedd, Wales[br]Welsh electrical engineer who greatly furthered the development and use of wireless telegraphy and the telephone in Britain, dominating British Post Office engineering during the last two decades of the nineteenth century.[br]After education at King's College, London, in 1852 Preece entered the office of Edwin Clark with the intention of becoming a civil engineer, but graduate studies at the Royal Institution under Faraday fired his enthusiasm for things electrical. His earliest work, as connected with telegraphy and in particular its application for securing the safe working of railways; in 1853 he obtained an appointment with the Electric and National Telegraph Company. In 1856 he became Superintendent of that company's southern district, but four years later he moved to telegraph work with the London and South West Railway. From 1858 to 1862 he was also Engineer to the Channel Islands Telegraph Company. When the various telegraph companies in Britain were transferred to the State in 1870, Preece became a Divisional Engineer in the General Post Office (GPO). Promotion followed in 1877, when he was appointed Chief Electrician to the Post Office. One of the first specimens of Bell's telephone was brought to England by Preece and exhibited at the British Association meeting in 1877. From 1892 to 1899 he served as Engineer-in-Chief to the Post Office. During this time he made a number of important contributions to telegraphy, including the use of water as part of telegraph circuits across the Solent (1882) and the Bristol Channel (1888). He also discovered the existence of inductive effects between parallel wires, and with Fleming showed that a current (thermionic) flowed between the hot filament and a cold conductor in an incandescent lamp.Preece was distinguished by his administrative ability, some scientific insight, considerable engineering intuition and immense energy. He held erroneous views about telephone transmission and, not accepting the work of Oliver Heaviside, made many errors when planning trunk circuits. Prior to the successful use of Hertzian waves for wireless communication Preece carried out experiments, often on a large scale, in attempts at wireless communication by inductive methods. These became of historic interest only when the work of Maxwell and Hertz was developed by Guglielmo Marconi. It is to Preece that credit should be given for encouraging Marconi in 1896 and collaborating with him in his early experimental work on radio telegraphy.While still employed by the Post Office, Preece contributed to the development of numerous early public electricity schemes, acting as Consultant and often supervising their construction. At Worcester he was responsible for Britain's largest nineteenth-century public hydro-electric station. He received a knighthood on his retirement in 1899, after which he continued his consulting practice in association with his two sons and Major Philip Cardew. Preece contributed some 136 papers and printed lectures to scientific journals, ninety-nine during the period 1877 to 1894.[br]Principal Honours and DistinctionsCB 1894. Knighted (KCB) 1899. FRS 1881. President, Society of Telegraph Engineers, 1880. President, Institution of Electrical Engineers 1880, 1893. President, Institution of Civil Engineers 1898–9. Chairman, Royal Society of Arts 1901–2.BibliographyPreece produced numerous papers on telegraphy and telephony that were presented as Royal Institution Lectures (see Royal Institution Library of Science, 1974) or as British Association reports.1862–3, "Railway telegraphs and the application of electricity to the signaling and working of trains", Proceedings of the ICE 22:167–93.Eleven editions of Telegraphy (with J.Sivewright), London, 1870, were published by 1895.1883, "Molecular radiation in incandescent lamps", Proceedings of the Physical Society 5: 283.1885. "Molecular shadows in incandescent lamps". Proceedings of the Physical Society 7: 178.1886. "Electric induction between wires and wires", British Association Report. 1889, with J.Maier, The Telephone.1894, "Electric signalling without wires", RSA Journal.1898, "Aetheric telegraphy", Proceedings of the Institution of Electrical Engineers.Further ReadingJ.J.Fahie, 1899, History of Wireless Telegraphy 1838–1899, Edinburgh: Blackwood. E.Hawkes, 1927, Pioneers of Wireless, London: Methuen.E.C.Baker, 1976, Sir William Preece, F.R.S. Victorian Engineer Extraordinary, London (a detailed biography with an appended list of his patents, principal lectures and publications).D.G.Tucker, 1981–2, "Sir William Preece (1834–1913)", Transactions of the Newcomen Society 53:119–36 (a critical review with a summary of his consultancies).GW / KFBiographical history of technology > Preece, Sir William Henry
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9 Baird, John Logie
[br]b. 13 August 1888 Helensburgh, Dumbarton, Scotlandd. 14 June 1946 Bexhill-on-Sea, Sussex, England[br]Scottish inventor of mechanically-based television.[br]Baird attended Larchfield Academy, then the Royal Technical College and Glasgow University. However, before he could complete his electrical-engineering degree, the First World War began, although poor health kept him out of the armed services.Employed as an engineer at the Clyde Valley Electrical Company, he lost his position when his diamond-making experiment caused a power failure in Glasgow. He then went to London, where he lived with his sister and tried manufacturing household products of his own design. To recover from poor health, he then went to Hastings and, using scrap materials, began experiments with imaging systems. In 1924 he transmitted outline images over wires, and by 1925 he was able to transmit recognizable human faces. In 1926 he was able to transmit moving images at a resolution of thirty lines per image and a frequency of ten images per second over an infrared link. Also that year, he started the world's first television station, which he named 2TV. In 1927 he transmitted moving images from London to Glasgow, and later that year to a passenger liner. In 1928 he demonstrated colour television.In 1936, when the BBC wanted to begin television service, Baird's system lost out in a competition with Marconi Electric and Musical Industries (EMI). In 1946 Baird reported that he had successfully completed research on a stereo television system.[br]Further ReadingR.Tiltman, 1933, Baird of Television, London: Seeley Service; repub. 1974, New York: Arno Press.J.Rowland, 1967, The Television Man: The Story of John Logie Baird, New York: Roy Publishers.F.Macgregor, 1984, Famous Scots, Gordon Wright (contains a short biography on Baird).HO -
10 Branly, Edouard Eugène
[br]b. 23 October 1844 Amiens, Franced. 24 March 1940 Paris, France[br]French electrical engineer, who c.1890 invented the coherer for detecting radio waves.[br]Branly received his education at the Lycée de Saint Quentin in the Département de l'Aisne and at the Henri IV College of Paris University, where he became a Fellow of the University, graduating as a Doctor of Physics in 1873. That year he was appointed a professor at the College of Bourges and Director of Physics Instruction at the Sorbonne. Three years later he moved to the Free School in Paris as Professor of Advanced Studies. In addition to these responsibilities, he qualified as an MD in 1882 and practised medicine from 1896 to 1916. Whilst carrying out experiments with Hertzian (radio) waves in 1890, Branly discovered that a tube of iron filings connected to a source of direct voltage only became conductive when the radio waves were present. This early form of rectifier, which he called a coherer and which needed regular tapping to maintain its response, was used to operate a relay when the waves were turned on and off by Morse signals, thus providing the first practical radio communication.[br]Principal Honours and DistinctionsPapal Order of Commander of St George 1899. Légion d'honneur, Chevalier 1900, Commandeur 1925. Osiris Prize (jointly with Marie Curie) 1903. Argenteuil Prize and Associate of the Royal Belgian Academy 1910. Member of the Academy of Science 1911. State Funeral at Notre Dame Cathedral.BibliographyAmongst his publications in Comptes rendus were "Conductivity of mediocre conductors", "Conductivity of gases", "Telegraphic conduction without wires" and "Conductivity of imperfect conductors realised at a distance by wireless by spark discharge of a capacitor".Further ReadingE.Hawkes, 1927, Pioneers of Wireless, London: Methuen. E.Larien, 1971, A History of Invention, London: Victor Gollancz.V.J.Phillips: 1980, Early Radio Wave Detectors, London: Peter Peregrinus.KF -
11 Broadcasting
See also: INDEX BY SUBJECT AREA[br] -
12 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 -
13 Eccles, William Henry
[br]b. 23 August 1875 Ulverston, Cumbria, Englandd. 27 April 1966 Oxford, England[br]English physicist who made important contributions to the development of radio communications.[br]After early education at home and at private school, Eccles won a scholarship to the Royal College of Science (now Imperial College), London, where he gained a First Class BSc in physics in 1898. He then worked as a demonstrator at the college and studied coherers, for which he obtained a DSc in 1901. Increasingly interested in electrical engineering, he joined the Marconi Company in 1899 to work on oscillators at the Poole experimental radio station, but in 1904 he returned to academic life as Professor of Mathematics and Physics and Department Head at South West Polytechnic, Chelsea. There he discovered ways of using the negative resistance of galena-crystal detectors to generate oscillations and gave a mathematical description of the operation of the triode valve. In 1910 he became Reader in Engineering at University College, London, where he published a paper explaining the reflection of radio waves by the ionosphere and designed a 60 MHz short-wave transmitter. From 1916 to 1926 he was Professor of Applied Physics and Electrical Engineering at the Finsbury City \& Guilds College and a private consulting engineer. During the First World War he was a military scientific adviser and Secretary to the Joint Board of Scientific Societies. After the war he made many contributions to electronic-circuit development, many of them (including the Eccles-Jordan "flip-flop" patented in 1918 and used in binary counters) in conjunction with F.W.Jordan, about whom little seems to be known. Illness forced Eccles's premature academic retirement in 1926, but he remained active as a consultant for many years.[br]Principal Honours and DistinctionsFRS 1921. President, Institution of Electrical Engineers, 1926–7. President, Physical Society 1929. President, Radio Society of Great Britain.Bibliography1912, "On the diurnal variation of the electric waves occurring in nature and on the propagation of electric waves round the bend of the earth", Proceedings of the Royal Society 87:79. 1919, with F.W.Jordan, "Method of using two triode valves in parallel for generating oscillations", Electrician 299:3.1915, Handbook of Wireless Telegraphy.1921, Continuous Wave Wireless Telegraphy.Further Reading1971, "William Henry Eccles, 1875–1966", Biographical Memoirs of the Royal Society, London, 17.KF -
14 Edison, Thomas Alva
SUBJECT AREA: Architecture and building, Automotive engineering, Electricity, Electronics and information technology, Metallurgy, Photography, film and optics, Public utilities, Recording, Telecommunications[br]b. 11 February 1847 Milan, Ohio, USAd. 18 October 1931 Glenmont[br]American inventor and pioneer electrical developer.[br]He was the son of Samuel Edison, who was in the timber business. His schooling was delayed due to scarlet fever until 1855, when he was 8½ years old, but he was an avid reader. By the age of 14 he had a job as a newsboy on the railway from Port Huron to Detroit, a distance of sixty-three miles (101 km). He worked a fourteen-hour day with a stopover of five hours, which he spent in the Detroit Free Library. He also sold sweets on the train and, later, fruit and vegetables, and was soon making a profit of $20 a week. He then started two stores in Port Huron and used a spare freight car as a laboratory. He added a hand-printing press to produce 400 copies weekly of The Grand Trunk Herald, most of which he compiled and edited himself. He set himself to learn telegraphy from the station agent at Mount Clements, whose son he had saved from being run over by a freight car.At the age of 16 he became a telegraphist at Port Huron. In 1863 he became railway telegraphist at the busy Stratford Junction of the Grand Trunk Railroad, arranging a clock with a notched wheel to give the hourly signal which was to prove that he was awake and at his post! He left hurriedly after failing to hold a train which was nearly involved in a head-on collision. He usually worked the night shift, allowing himself time for experiments during the day. His first invention was an arrangement of two Morse registers so that a high-speed input could be decoded at a slower speed. Moving from place to place he held many positions as a telegraphist. In Boston he invented an automatic vote recorder for Congress and patented it, but the idea was rejected. This was the first of a total of 1180 patents that he was to take out during his lifetime. After six years he resigned from the Western Union Company to devote all his time to invention, his next idea being an improved ticker-tape machine for stockbrokers. He developed a duplex telegraphy system, but this was turned down by the Western Union Company. He then moved to New York.Edison found accommodation in the battery room of Law's Gold Reporting Company, sleeping in the cellar, and there his repair of a broken transmitter marked him as someone of special talents. His superior soon resigned, and he was promoted with a salary of $300 a month. Western Union paid him $40,000 for the sole rights on future improvements on the duplex telegraph, and he moved to Ward Street, Newark, New Jersey, where he employed a gathering of specialist engineers. Within a year, he married one of his employees, Mary Stilwell, when she was only 16: a daughter, Marion, was born in 1872, and two sons, Thomas and William, in 1876 and 1879, respectively.He continued to work on the automatic telegraph, a device to send out messages faster than they could be tapped out by hand: that is, over fifty words per minute or so. An earlier machine by Alexander Bain worked at up to 400 words per minute, but was not good over long distances. Edison agreed to work on improving this feature of Bain's machine for the Automatic Telegraph Company (ATC) for $40,000. He improved it to a working speed of 500 words per minute and ran a test between Washington and New York. Hoping to sell their equipment to the Post Office in Britain, ATC sent Edison to England in 1873 to negotiate. A 500-word message was to be sent from Liverpool to London every half-hour for six hours, followed by tests on 2,200 miles (3,540 km) of cable at Greenwich. Only confused results were obtained due to induction in the cable, which lay coiled in a water tank. Edison returned to New York, where he worked on his quadruplex telegraph system, tests of which proved a success between New York and Albany in December 1874. Unfortunately, simultaneous negotiation with Western Union and ATC resulted in a lawsuit.Alexander Graham Bell was granted a patent for a telephone in March 1876 while Edison was still working on the same idea. His improvements allowed the device to operate over a distance of hundreds of miles instead of only a few miles. Tests were carried out over the 106 miles (170 km) between New York and Philadelphia. Edison applied for a patent on the carbon-button transmitter in April 1877, Western Union agreeing to pay him $6,000 a year for the seventeen-year duration of the patent. In these years he was also working on the development of the electric lamp and on a duplicating machine which would make up to 3,000 copies from a stencil. In 1876–7 he moved from Newark to Menlo Park, twenty-four miles (39 km) from New York on the Pennsylvania Railway, near Elizabeth. He had bought a house there around which he built the premises that would become his "inventions factory". It was there that he began the use of his 200- page pocket notebooks, each of which lasted him about two weeks, so prolific were his ideas. When he died he left 3,400 of them filled with notes and sketches.Late in 1877 he applied for a patent for a phonograph which was granted on 19 February 1878, and by the end of the year he had formed a company to manufacture this totally new product. At the time, Edison saw the device primarily as a business aid rather than for entertainment, rather as a dictating machine. In August 1878 he was granted a British patent. In July 1878 he tried to measure the heat from the solar corona at a solar eclipse viewed from Rawlins, Wyoming, but his "tasimeter" was too sensitive.Probably his greatest achievement was "The Subdivision of the Electric Light" or the "glow bulb". He tried many materials for the filament before settling on carbon. He gave a demonstration of electric light by lighting up Menlo Park and inviting the public. Edison was, of course, faced with the problem of inventing and producing all the ancillaries which go to make up the electrical system of generation and distribution-meters, fuses, insulation, switches, cabling—even generators had to be designed and built; everything was new. He started a number of manufacturing companies to produce the various components needed.In 1881 he built the world's largest generator, which weighed 27 tons, to light 1,200 lamps at the Paris Exhibition. It was later moved to England to be used in the world's first central power station with steam engine drive at Holborn Viaduct, London. In September 1882 he started up his Pearl Street Generating Station in New York, which led to a worldwide increase in the application of electric power, particularly for lighting. At the same time as these developments, he built a 1,300yd (1,190m) electric railway at Menlo Park.On 9 August 1884 his wife died of typhoid. Using his telegraphic skills, he proposed to 19-year-old Mina Miller in Morse code while in the company of others on a train. He married her in February 1885 before buying a new house and estate at West Orange, New Jersey, building a new laboratory not far away in the Orange Valley.Edison used direct current which was limited to around 250 volts. Alternating current was largely developed by George Westinghouse and Nicola Tesla, using transformers to step up the current to a higher voltage for long-distance transmission. The use of AC gradually overtook the Edison DC system.In autumn 1888 he patented a form of cinephotography, the kinetoscope, obtaining film-stock from George Eastman. In 1893 he set up the first film studio, which was pivoted so as to catch the sun, with a hinged roof which could be raised. In 1894 kinetoscope parlours with "peep shows" were starting up in cities all over America. Competition came from the Latham Brothers with a screen-projection machine, which Edison answered with his "Vitascope", shown in New York in 1896. This showed pictures with accompanying sound, but there was some difficulty with synchronization. Edison also experimented with captions at this early date.In 1880 he filed a patent for a magnetic ore separator, the first of nearly sixty. He bought up deposits of low-grade iron ore which had been developed in the north of New Jersey. The process was a commercial success until the discovery of iron-rich ore in Minnesota rendered it uneconomic and uncompetitive. In 1898 cement rock was discovered in New Village, west of West Orange. Edison bought the land and started cement manufacture, using kilns twice the normal length and using half as much fuel to heat them as the normal type of kiln. In 1893 he met Henry Ford, who was building his second car, at an Edison convention. This started him on the development of a battery for an electric car on which he made over 9,000 experiments. In 1903 he sold his patent for wireless telegraphy "for a song" to Guglielmo Marconi.In 1910 Edison designed a prefabricated concrete house. In December 1914 fire destroyed three-quarters of the West Orange plant, but it was at once rebuilt, and with the threat of war Edison started to set up his own plants for making all the chemicals that he had previously been buying from Europe, such as carbolic acid, phenol, benzol, aniline dyes, etc. He was appointed President of the Navy Consulting Board, for whom, he said, he made some forty-five inventions, "but they were pigeonholed, every one of them". Thus did Edison find that the Navy did not take kindly to civilian interference.In 1927 he started the Edison Botanic Research Company, founded with similar investment from Ford and Firestone with the object of finding a substitute for overseas-produced rubber. In the first year he tested no fewer than 3,327 possible plants, in the second year, over 1,400, eventually developing a variety of Golden Rod which grew to 14 ft (4.3 m) in height. However, all this effort and money was wasted, due to the discovery of synthetic rubber.In October 1929 he was present at Henry Ford's opening of his Dearborn Museum to celebrate the fiftieth anniversary of the incandescent lamp, including a replica of the Menlo Park laboratory. He was awarded the Congressional Gold Medal and was elected to the American Academy of Sciences. He died in 1931 at his home, Glenmont; throughout the USA, lights were dimmed temporarily on the day of his funeral.[br]Principal Honours and DistinctionsMember of the American Academy of Sciences. Congressional Gold Medal.Further ReadingM.Josephson, 1951, Edison, Eyre \& Spottiswode.R.W.Clark, 1977, Edison, the Man who Made the Future, Macdonald \& Jane.IMcN -
15 Eisler, Paul
[br]b. 1907 Vienna, Austria[br]Austrian engineer responsible for the invention of the printed circuit.[br]At the age of 23, Eisler obtained a Diploma in Engineering from the Technical University of Vienna. Because of the growing Nazi influence in Austria, he then accepted a post with the His Master's Voice (HMV) agents in Belgrade, where he worked on the problems of radio reception and sound transmission in railway trains. However, he soon returned to Vienna to found a weekly radio journal and file patents on graphical sound recording (for which he received a doctorate) and on a system of stereoscopic television based on lenticular vertical scanning.In 1936 he moved to England and sold the TV patent to Marconi for £250. Unable to find a job, he carried out experiments in his rooms in a Hampstead boarding-house; after making circuits using strip wires mounted on bakelite sheet, he filed his first printed-circuit patent that year. He then tried to find ways of printing the circuits, but without success. Obtaining a post with Odeon Theatres, he invented a sound-level control for films and devised a mirror-drum continuous-film projector, but with the outbreak of war in 1939, when the company was evacuated, he chose to stay in London and was interned for a while. Released in 1941, he began work with Henderson and Spalding, a firm of lithographic printers, to whom he unwittingly assigned all future patents for the paltry sum of £1. In due course he perfected a means of printing conducting circuits and on 3 February 1943 he filed three patents covering the process. The British Ministry of Defence rejected the idea, considering it of no use for military equipment, but after he had demonstrated the technique to American visitors it was enthusiastically taken up in the US for making proximity fuses, of which many millions were produced and used for the war effort. Subsequently the US Government ruled that all air-borne electronic circuits should be printed.In the late 1940s the Instrument Department of Henderson and Spalding was split off as Technograph Printed Circuits Ltd, with Eisler as Technical Director. In 1949 he filed a further patent covering a multilayer system; this was licensed to Pye and the Telegraph Condenser Company. A further refinement, patented in the 1950s, the use of the technique for telephone exchange equipment, but this was subsequently widely infringed and although he negotiated licences in the USA he found it difficult to license his ideas in Europe. In the UK he obtained finance from the National Research and Development Corporation, but they interfered and refused money for further development, and he eventually resigned from Technograph. Faced with litigation in the USA and open infringement in the UK, he found it difficult to establish his claims, but their validity was finally agreed by the Court of Appeal (1969) and the House of Lords (1971).As a freelance inventor he filed many other printed-circuit patents, including foil heating films and batteries. When his Patent Agents proved unwilling to fund the cost of filing and prosecuting Complete Specifications he set up his own company, Eisler Consultants Ltd, to promote food and space heating, including the use of heated cans and wallpaper! As Foil Heating Ltd he went into the production of heating films, the process subsequently being licensed to Thermal Technology Inc. in California.[br]Bibliography1953, "Printed circuits: some general principles and applications of the foil technique", Journal of the British Institution of Radio Engineers 13: 523.1959, The Technology of Printed Circuits: The Foil Technique in Electronic Production.1984–5, "Reflections of my life as an inventor", Circuit World 11:1–3 (a personal account of the development of the printed circuit).1989, My Life with the Printed Circuit, Bethlehem, Pennsylvania: Lehigh University Press.KF -
16 Electronics and information technology
See also: INDEX BY SUBJECT AREA[br]Byron, Ada AugustaNapier, JohnRiche, Gaspard-Clair-François-MarieSchickhard, WilhelmBiographical history of technology > Electronics and information technology
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17 Kennelly, Arthur Edwin
[br]b. 17 December 1871 Colaba, Bombay, Indiad. 18 June 1939 Boston, Massachusetts, USA[br]Anglo-American electrical engineer who predicted the ionosphere and developed mathematical analysis for electronic circuits.[br]As a young man, Kennelly worked as office boy for a London engineering society, as an electrician and on a cable-laying ship. In 1887 he went to work for Thomas Edison at West Orange, New Jersey, USA, becoming his chief assistant. In 1894, with Edwin J.Houston, he formed the Philadelphia company of Houston and Kennelly, but eight years later he took up the Chair of Electrical Engineering at Harvard, a post he held until his retirement in 1930. In 1902 he noticed that the radio signals received by Marconi in Nova Scotia from the transmitter in England were stronger than predicted and postulated a reflecting ionized layer in the upper atmosphere. Almost simultaneously the same prediction was made in England by Heaviside, so the layer became known as the Kennelly-Heaviside layer. Throughout most of his working life Kennelly was concerned with the application of mathematical techniques, particularly the use of complex theory, to the analysis of electrical circuits. With others he also contributed to an understanding of the high-frequency skin-effect in conductors.[br]Principal Honours and DistinctionsPresident, American Institute of Electrical Engineers 1898–1900. President, Institution of Electrical Engineers 1916. Institute of Electrical and Electronics Engineers Medal of Honour 1932; Edison Medal 1933.Bibliography1915, with F.A.Laws \& P.H.Pierce "Experimental research on the skin effect in conductors", Transactions of the American Institute of Electrical Engineers 34:1,953.1924, Hyperbolic Functions as Applied to Electrical Engineering.1924, Check Atlas of Complex Hyperbolic \& Circular Functions (both on mathematics for circuit analysis).Further ReadingK.Davies, 1990, Ionospheric Radio, London: Peter Peregrinus. See also Appleton, Sir Edward Victor.KF -
18 Lodge, Sir Oliver Joseph
[br]b. 12 June 1851 Penkhull, Staffordshire, Englandd. 22 August 1940 Lake, near Salisbury, Wiltshire, England[br]English physicist who perfected Branly's coherer; said to have given the first public demonstration of wireless telegraphy.[br]At the age of 8 Lodge entered Newport Grammar School, and in 1863–5 received private education at Coombs in Suffolk. He then returned to Staffordshire, where he assisted his father in the potteries by working as a book-keeper. Whilst staying with an aunt in London in 1866–7, he attended scientific lectures and became interested in physics. As a result of this and of reading copies of English Mechanic magazine, when he was back home in Hanley he began to do experiments and attended the Wedgewood Institute. Returning to London c. 1870, he studied initially at the Royal College of Science and then, from 1874, at University College, London (UCL), at the same time attending lectures at the Royal Institution.In 1875 he obtained his BSc, read a paper to the British Association on "Nodes and loops in chemical formulae" and became a physics demonstrator at UCL. The following year he was appointed a physics lecturer at Bedford College, completing his DSc in 1877. Three years later he became Assistant Professor of Mathematics at UCL, but in 1881, after only two years, he accepted the Chair of Experimental Physics at the new University College of Liverpool. There began a period of fruitful studies of electricity and radio transmission and reception, including development of the lightning conductor, discovery of the "coherent" effect of sparks and improvement of Branly's coherer, and, in 1894, what is said to be the first public demonstration of the transmission and reception (using a coherer) of wireless telegraphy, from Lewis's department store to the clock tower of Liverpool University's Victoria Building. On 10 May 1897 he filed a patent for selective tuning by self-in-ductance; this was before Marconi's first patent was actually published and its priority was subsequently upheld.In 1900 he became the first Principal of the new University of Birmingham, where he remained until his retirement in 1919. In his later years he was increasingly interested in psychical research.[br]Principal Honours and DistinctionsKnighted 1902. FRS 1887. Royal Society Council Member 1893. President, Society for Psychical Research 1901–4, 1932. President, British Association 1913. Royal Society Rumford Medal 1898. Royal Society of Arts Albert Medal 1919. Institution of Electrical Engineers Faraday Medal 1932. Fourteen honorary degrees from British and other universities.Bibliography1875, "The flow of electricity in a plane", Philosophical Magazine (May, June and December).1876, "Thermo-electric phenomena", Philosophical Magazine (December). 1888, "Lightning conductors", Philosophical Magazine (August).1889, Modern Views of Electricity (lectures at the Royal Institution).10 May 1897, "Improvements in syntonized telegraphy without line wires", British patent no. 11,575, US patent no. 609,154.1898, "Radio waves", Philosophical Magazine (August): 227.1931, Past Years, An Autobiography, London: Hodder \& Stoughton.Further ReadingW.P.Jolly, 1974, Sir Oliver Lodge, Psychical Resear cher and Scientist, London: Constable.E.Hawks, 1927, Pioneers of Wireless, London: Methuen.See also: Hertz, Heinrich RudolphKFBiographical history of technology > Lodge, Sir Oliver Joseph
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19 Pierce, John Robinson
[br]b. 27 March 1910 Des Moines, Iowa, USA[br]American scientist and communications engineer said to be the "father" of communication satellites.[br]From his high-school days, Pierce showed an interest in science and in science fiction, writing under the pseudonym of J.J.Coupling. After gaining Bachelor's, Master's and PhD degrees at the California Institute of Technology (CalTech) in Pasadena in 1933, 1934 and 1936, respectively, Pierce joined the Bell Telephone Laboratories in New York City in 1936. There he worked on improvements to the travelling-wave tube, in which the passage of a beam of electrons through a helical transmission line at around 7 per cent of the speed of light was made to provide amplification at 860 MHz. He also devised a new form of electrostatically focused electron-multiplier which formed the basis of a sensitive detector of radiation. However, his main contribution to electronics at this time was the invention of the Pierce electron gun—a method of producing a high-density electron beam. In the Second World War he worked with McNally and Shepherd on the development of a low-voltage reflex klystron oscillator that was applied to military radar equipment.In 1952 he became Director of Electronic Research at the Bell Laboratories' establishment, Murray Hill, New Jersey. Within two years he had begun work on the possibility of round-the-world relay of signals by means of communication satellites, an idea anticipated in his early science-fiction writings (and by Arthur C. Clarke in 1945), and in 1955 he published a paper in which he examined various possibilities for communications satellites, including passive and active satellites in synchronous and non-synchronous orbits. In 1960 he used the National Aeronautics and Space Administration 30 m (98 1/2 ft) diameter, aluminium-coated Echo 1 balloon satellite to reflect telephone signals back to earth. The success of this led to the launching in 1962 of the first active relay satellite (Telstar), which weighed 170 lb (77 kg) and contained solar-powered rechargeable batteries, 1,000 transistors and a travelling-wave tube capable of amplifying the signal 10,000 times. With a maximum orbital height of 3,500 miles (5,600 km), this enabled a variety of signals, including full bandwidth television, to be relayed from the USA to large receiving dishes in Europe.From 1971 until his "retirement" in 1979, Pierce was Professor of Electrical Engineering at CalTech, after which he became Chief Technologist at the Jet Propulsion Laboratories, also in Pasadena, and Emeritus Professor of Engineering at Stanford University.[br]Principal Honours and DistinctionsInstitute of Electrical and Electronics Engineers Morris N.Liebmann Memorial Award 1947; Edison Medal 1963; Medal of Honour 1975. Franklin Institute Stuart Ballantine Award 1960. National Medal of Science 1963. Danish Academy of Science Valdemar Poulsen Medal 1963. Marconi Award 1974. National Academy of Engineering Founders Award 1977. Japan Prize 1985. Arthur C.Clarke Award 1987. Honorary DEng Newark College of Engineering 1961. Honorary DSc Northwest University 1961, Yale 1963, Brooklyn Polytechnic Institute 1963. Editor, Proceedings of the Institute of Radio Engineers 1954–5.Bibliography23 October 1956, US patent no. 2,768,328 (his development of the travelling-wave tube, filed on 5 November 1946).1947, with L.M.Field, "Travelling wave tubes", Proceedings of the Institute of RadioEngineers 35:108 (describes the pioneering improvements to the travelling-wave tube). 1947, "Theory of the beam-type travelling wave tube", Proceedings of the Institution ofRadio Engineers 35:111. 1950, Travelling Wave Tubes.1956, Electronic Waves and Messages. 1962, Symbols, Signals and Noise.1981, An Introduction to Information Theory: Symbols, Signals and Noise: Dover Publications.1990, with M.A.Knoll, Signals: Revolution in Electronic Communication: W.H.Freeman.KF -
20 Telecommunications
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См. также в других словарях:
Marconi — may refer to: Contents 1 People 2 Businesses 3 Places 4 Other uses People Guglielmo Marconi, Italian born radio p … Wikipedia
Marconi — ist ein ehemals börsengehandelter britischer Telekommunikations Ausrüster mit Sitz in London, der im Januar 2006 von Ericsson aufgekauft wurde, aber noch als rechtlich selbständiges Unternehmen existiert. Das Unternehmen entwickelt, produziert… … Deutsch Wikipedia
marconi — [ markɔni ] adj. inv. • déb. XXe ; de Marconi, n. pr. ♦ Mar. Gréement marconi, caractérisé par une grand voile triangulaire hissée au moyen d une drisse unique sur un mât à pible haubané. ● marconi nom masculin (de G. Marconi, nom propre)… … Encyclopédie Universelle
MARCONI (G.) — MARCONI GUGLIELMO (1874 1937) Physicien et inventeur italien né à Bologne et mort à Rome. Dans l’histoire de la télégraphie sans fil, Guglielmo Marconi intervient au moment où des découvertes fragmentaires mais capitales n’attendent plus que… … Encyclopédie Universelle
Marconi — Marconi, Guglielmo Marchese (seit 1929), italienischer Ingenieur und Physiker, * Bologna 25. 4. 1874, ✝ Rom 20. 7. 1937. Ab 1896 in England tätig, widmete sich Marconi als Geschäftsmann vorwiegend der Leitung seines 1897 gegründeten… … Universal-Lexikon
Marconi — Mar*co ni, prop. a. [After Guglielmo Marconi (b. 1874), Italian inventor.] Designating, or pert. to, Marconi s system of wireless telegraphy; as, Marconi a[ e]rial, coherer, station, system, etc. [archaic] [Webster 1913 Suppl.] … The Collaborative International Dictionary of English
Marconi® — /mär kōˈni/ adjective Relating to the Italian physicist Guglielmo Marconi (1874–1937), or his system of wireless telegraphy transitive verb and intransitive verb (without cap) to communicate by wireless telegraphy marcōˈnigram noun A message so… … Useful english dictionary
Marcōni — Marcōni, Guilelmo, Erfinder der drahtlosen Telegraphie, geb. 25. April 1874 in Griffone bei Bologna, studierte in Livorno und Bologna, beschäftigte sich seit 1895 mit Versuchen, die Hertzschen elektrischen Wellen zur Übertragung von Nachrichten… … Meyers Großes Konversations-Lexikon
Marconi — Marcōni, Guilelmo, Erfinder der Telegraphie ohne Draht, geb. 25. April 1874 in Griffone bei Bologna, ging 1896 nach England; unterstützt das. von der Wireless Telegraph Company, gelang es ihm 1902 von der irischen zur kanad. Küste Zeichen zu… … Kleines Konversations-Lexikon
Marconi — Marchese Guglielmo … Scientists
Marconi's — Marconi , Marchese Guglielmo … Scientists
