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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The practical possibility of transmitting sound via air, or “radio telephony”, is linked to the development of amplification techniques. It was the American inventor Lee De Forest who gave the decisive stimulus in 1906-7 by devising the triode, a vacuum tube capable of amplifying, in a controllable manner, the signal (voltage) detected: it was an improvement of the diode, introduced in 1905 by the English inventor Ambrose Fleming. De Forest quickly caught on that the principal application for his invention was in the audio field, so much so that he named his most evolved version “Audion”. However, it was the Canadian inventor Reginald Aubrey Fessenden who carried out, always in 1906, the first experiments in radiotelephony, not only with the objective of transmitting sound, as with the Morse code, but to send through the air complete audio signals. At the root of these developments lies another important invention, the microphone, introduced by Thomas Edison in the early 1880's as an evolution and improvement of communication via telephone. Radio telephony quickly found its place in the fields that were dominated by wireless telegraphy (communication between vehicles in motion, communication in the military) but in no more than a few years it developed into something that even Marconi had not foreseen, broadcasting, in other words the radio as a means of mass communication. Beginning in the Fifties the triode vacuum tube was progressively substituted with a new instrument for amplification, the transistor, which allowed for the miniaturization of the radio, and made it become portable.
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Following the celebrations of the 90 years from its foundation in 1923, the Liceo Righi in Bologna and the Marconi Foundation organized from February to April 2014 a scientific-historical workshop for the students of the last three years. The workshop dealt with the relations between the two famous Bolognese physicists, Augusto Righi and Guglielmo Marconi, and focused on the analysis of the Righi Collection, preserved at the Marconi Foundation. The workshop was coordinated by professor Elisabetta Golinelli and Barbara Valotti. Mario Giorgi was the students’ tutor during the project, while Maurizio Bigazzi worked as a technical consultant for the devices created by the two scientists. The meetings took place part at the Liceo Righi and part at Villa Griffone.
The activity was mainly focused on examining the various newspaper articles belonging to the Collection. Such articles and clippings had all been selected, preserved and sometime annotated by Augusto Righi himself , and later on by his son Aldo. At first such material was briefly divided in “entries”, afterwards it was compared with other sources of the period and with the relevant critical writings, it was then evaluated and selected, and finally organized in the following subjects: • Righi and Marconi biographical notes All these subjects were inevitably seen through the lenses of the Italian and foreign press of the period. Divided in subgroups, the students analyzed the various subjects in details and prepared a final presentation including a choice of materials (photographs and scans) and full of data, annotations and remarks, which was illustrated by all students in turn.
The workshop ended on Saturday 12 April, with a public conference at the Liceo Righi Lecture Hall. The students presented the results of their work, which in the end was welcomed by Gabriele Falciasecca as a positive model to be used on future occasions. The students involved in the project were Tommaso Branzaglia, Federico Brunello, Ulisse Caputo, Filippo Frabetti, Alessandro Fusco, Matteo Lanzarini, Francesco Pipi, Michele Proni, Michele Raspanti, Federico Rinaldi, Riccardo Tinti.
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| In 1945 Arthur Clarke, one of the most renowned science fiction writers (author also of 2001: A Space Odyssey), was still a young English physicist: he published an article, relatively unnoticed, in which he hypothesized the possibility of launching a “geostationary” satellite, that is to say one that revolves at the same velocity of the earth and thus in a stable position with respect to the planet, and to make of this satellite an instrument for telecommunications, obviously via radio, at long-distance.
In 1962 the first satellite for intercontinental telecommunications was launched: the Telstar, which guaranteed both television broadcasts between Europe and America as well as a continental telephone channel in alternative to the costly and unsafe underwater cables. By 1966 a system of three geostationary satellites was in place, capable of connecting all continents and allowing for a simultaneous “worldwide vision”. Beginning in the early Seventies, some countries with vaster territories, first and foremost USA and USSR, introduced the use of the satellite to simultaneously transmit the same television signal in areas that were very distant from one to the other. By mid decade, broadcasts via satellite began and they were received by homes with special antennas (parabolic satellite dishes); today the satellite is, with the traditional broadcasting systems via air and via cable, the third channel for diffusing television signals. Beginning in the Eighties, the use of satellites for telecommunications noticeably increased, thanks also to the growing request on the one hand of instruments for managing global telephone traffic, on the other of instruments for real time monitoring of vehicles in motion.
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© 2013 - Fondazione Guglielmo Marconi - Villa Griffone - via Celestini 1 - 40037 Pontecchio Marconi (BO) - C.F 80063250379