Guglielmo Marconi (April 25th 1874 - July 20th 1937) is a physicist and Italian business man . Being based on the discoveries of Hertz, Popov, Branly and Lodge, it carries out many experiments on the propagation of the hertzian Onde S. He is regarded wrongly as the promoter of the transmissions by radio or TSF. In 1943, the supreme court of the United States recognizes the anteriority of work on the radio with Nicolas Tesla.

Born with Bologna (Italy) on April 25th, 1874 in an easy family, it begins her studies with Florence (Italy) where appears its passion for the Physique and the experimentation. Admitted in the capacity as listener at the University of Bologna, it follows some courses of Augusto Righi

• 1895 Expériences on the waves discovered by Hertz seven years before. It reproduces the material used by Hertz by improving it with a coherer of Branly to increase the sensitivity and the antenna of Popov. It carries out in the Swiss Alps with Salvan Valais a connection of 1,5 km during the summer 1895. Foundation Marconi
• 1896 Fault of being followed by its Compatriot S, it leaves for the England, continues its experiments and deposits a Brevet.
• May 1897 First communication in Morse with more than 13 km between Lavernock (Wales) and Brean (England) over the Channel of Bristol-board.
• July 1897, return in Italy or the Italian royal Marine enables him to carry out tests between a fixed transmitter located in the arsenal of San Bartolomeo at Spezia (Italy) and a receiver on board the tug boat San Martino . The antenna used was 34 m length. A range of 18 km was reached. Creation of the company Wireless Telegraph and Signal Company
• 1898 Opening of the first Factory of the world of the radios with Chelmsford, England.
• 1899 First connection transmanche by radio. The transmitted message is a telegram of homage to Edouard Branly, inventor of the coherer, without which this connection would not have been possible.
• 1900 Name change of the company which becomes the Marconi Wireless Telegraph Company . Deposit of the patent n°7777 on the use of circuit tuned allowing the use of several frequencies.
• 1901 Connection between the Corsica and the continent. First transatlantic connection between Poldhu (Cornouailles) and Newfoundland with (Canada). In addition to its spectacular character, this experiment made it possible to highlight the phenomena of propagation at long distance by reflection on the layers ionized of high the atmosphere (Couches of Kennelly-Heaviside)
• 1902 Invention of a magnetic detector
• 1904 Expériences on the directivity of the antenna S and use of the Diode of Fleming as a detector.
• 1909 Nobel Prize of physics with Karl Ferdinand Braun.
• April 15th 1912 Shipwreck of the Titanic. “All those which were saved it were thanks to a man, M.  Marconi… and with its marvellous invention” .
• 1918 Franklin Medal for the application of the radio waves to the communications.
• 1920 First radio broadcast of Chelmsford, England.
• 1922 First radiophonic regular emissions in the world since Writtle, close to the Chelmsford, England.
• 1922 Foundation of BBC by a consortium including G. Marconi in particular.
• 1924 Development of the world radiocommunications on short waves
• 1932 Developed of telephony on ultra-short waves
• July 20th 1937 Death of Marconi to Rome, birth of the RADAR.

See too

• Jagadish Chandra Bump