Marconi Museum |
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visits: Sunday at 10 am
working days on reservation
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 info visits
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Before the invention of the transistor, for almost half a century from the beginning of the 1900's, radios as well as many other electronic devises were basically valve sets. It was John Ambrose Fleming who invented the diode or thermionic valve. Fleming was born in Lancaster in 1849. He studied under the famous James Clerk Maxwell and then worked as a researcher and professor of electrical engineering in Cambridge, Nottingham and London. He also invented the right-hand rule of electromagnetism. In 1899, at the age of fifty, Fleming was already a famous scientist. He accepted Marconi's proposal to work with him and became his scientific consultant. He was immediately involved in the technical breakthrough that many people thought impossible – the wireless transmission across the Atlantic Ocean. Fleming played a key role in planning the stations that allowed Marconi, on 12 December 1901, to establish his historic wireless connection across the Atlantic. The relationship between Marconi and Fleming continued for years and although they did not always get along very well Marconi never interfered with Fleming's personal research. In 1904 Fleming devised the first prototype thermionic valve. Although its application was not yet clear, Marconi decided to produce it as a new electromagnetic detector in his Chelmsford factory. Marconi’s Nobel lecture held at the Swedish Royal Academy proves how much he trusted and valued Fleming. When talking about the development of his experiments, Marconi cited a long extract from Fleming’s book The Principles of Electric Wave Telegraphy, published in London in 1906. He referred to the book several times and also recalled Fleming’s contribution to the transatlantic adventure. Marconi held Fleming in great esteem, even though they had different opinions – for instance on the relationship between daylight and wavelength. Fleming worked as a scientific consultant for the Marconi Company until 1931 and died aged ninety-six in 1945.
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Karl Ferdinand Braun, who in 1909 shared the Nobel Prize for Physics with Marconi, was born in Tulda, Germany in 1850. He taught at the universities of Würzburg, Marburg and Strassburg, the latter becoming his principal seat of activity. Around 1895 he carried out important research on the cathode ray, much of it using the tube he had invented (the so-called "Braun tube"), a prototype which would later develop into the modern-day cathode-ray tube. Braun left many writings on the electromagnetic theory of light. From 1898, after researching hydrotelegraphy, he devoted himself to wireless telegraphy and invented a system similar to Marconi's, but with some improvements. This equipment, called the Braun-Siemens system, began to compete with the A.E.G.-Slaby-Arco system in the race to develop an independent German wireless telegraphy system which was promoted by Emperor Wilhelm II. The race was concluded on 27 May 1903 by the union of the two systems and a new company was formed in order to protect the national interest from the overpowering success of the Marconi system. Like Adolf Slaby, Braun concentrated mainly on the development of ever more efficient and competitive devices although his contribution to the field of wireless telegraphy was not as important as that for the cathode-ray tube technology. When in 1909 at Stockholm, Braun was awarded the Nobel Prize together with Marconi, he was fifty-nine, more than two decades older than his Italian colleague. Although he had an outstanding background, many other scientists deserved the prize too and it is highly probable that his nomination at Marconi's side was political. Marconi at first refused to receive "half a prize", but finally decided to accept and went to Stockholm. However, when he gave his speech at the Swedish Royal Academy, he only cited Braun once, when he explained that part of his work on condensers in association with radiating antennae had been carried out simultaneously by Braun, without either of them knowing anything of the other's work. Some years later, Braun went to the United States to testify in court on the property of a patent and in 1918 he died in New York. He had not undertaken any new research for at least ten years.
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© 2013 - Fondazione Guglielmo Marconi - Villa Griffone - via Celestini 1 - 40037 Pontecchio Marconi (BO) - C.F 80063250379