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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«Mr. Marconi sends to Mr. Branly his regards over the Channel through the wireless telegraph, this nice achievement being partly the result of Mr. Branly's remarkable work.» With this telegram, sent from Dover on March 29th 1899, soon after the first wireless communication was made between France and England, the young Marconi paid homage to his illustrious colleague. Branly's contribution is briefly accounted for by Marconi ten years later, in his Nobel Lecture, where he explains to have used, in his early experiments, a Branly coherer as a detector, which he slightly modified to increase its stability. The crossbreed is interesting: the term “coherer” was coined by Lodge, Branly always rejected the concept, preferring “radioconductor”. Marconi, it seems, adopted Lodge's term/concept (quite diffused by then), but utilized Branly's apparatus. Branly was born in Amiens in 1844. He studied at the Sorbonne and at the Ecole Normale Supérieure. For more than 50 years he was professor of Physics at the Catholic University in Paris, becoming a scientific celebrity, especially in France, where for a long time he was considered the true inventor of wireless. In 1890 he published the first results of his researches that showed that the electric spark had the power at a distance to change the conductivity of the powdered conductors: this is his discovery, hotly contested by Calzecchi Onesti, who also greatly underestimated the importance of power at a distance. Having devised his “radioconductor”, Branly continued his research on electrical conductivity, with little participation in the future developments of wireless telegraphy. He thought of himself, above all, as an experimenter, and even if in some instances he served as a consultant and collaborator, he was never seriously attracted to carrying out applied research, to the point that when in 1912 Marconi offered him a job as a technical consultant of his Company (by then well established), Branly kindly refused. With a degree also in medicine, as of 1896, for about twenty years, he practiced electrotherapy in his own laboratory. He became interested in the “psychic sciences” and telemechanics. In 1900 he was nominated Chevalier of the Legion of Honor and in 1911 became a member of the Academy of Sciences. He died in Paris in 1940, after having dedicated his entire life to scientific studies.
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Born in New York in 1890, Edwin Armstrong graduated in engineering from Columbia University, and later served in France during the First World War, enlisted in the U.S. Army Signal Corps. There he patented the superheterodyne circuit, that he had been developing for quite some time, but was obliged to face a lawsuit, which he lost to Lucien Lévy. Upon his return home, he faced a wearing legal battle (1922-1934) with De Forest for the rights over the feedback or regenerative circuit. Even in this case, after varying sentences, Armstrong was not able to obtain full recognition for his original contribution. In the meantime, he was perfecting a system of frequency-modulated (FM) transmission, in place of amplitude-modulated (AM) transmission, a system which he patented in 1933, after years of experimentation in the laboratories of Columbia University. In 1937 he financed the construction of the first FM radio station in Alpine (New Jersey). But the FM system encountered much resistance, on the one hand because it challenged an industrial organization founded on the AM system and, on the other hand, because it presented itself as an eligible candidate in the competitive tender for the wave band allocation, in which the newly born television was also participating. In 1945, the frequency allocations established by the FCC (Federal Communications Commission), under the influence of David Sarnoff's RCA (Radio Corporation of America), penalized the FM system and Armstrong, who could have obtained significant rights from his patent. Rights, however, that the RCA did not want to recognize, resulting in another legal battle. Armstrong, who had also collaborated with the U.S. Army in the Second World War, making improvements to the long distance FM system and to continuous wave radar, patented in 1953 the Multiplexing FM, a system of multiple transmissions on the same wavelength. Forced to negotiate with the RCA because he was no longer able to sustain the legal fees, Armstrong fell into a deep depression and, on January 31st 1954, committed suicide, jumping to his death from the thirteenth floor of his New York apartment. Marion, the widow, took up the case again against RCA and, after a long process, finally obtained justice. Armstrong's career, marked and almost jinxed by the trials of the patent disputes, came to a tragic conclusion. On the contrary, the successive developments in radio transmission proved all of his merits, so much so that today we still enjoy some of his precious intuitions.
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© 2013 - Fondazione Guglielmo Marconi - Villa Griffone - via Celestini 1 - 40037 Pontecchio Marconi (BO) - C.F 80063250379