Guglielmo Marconi - Designed and constructed the first Wireless telegraph

Born: 25th Apr 1874 | Died: 14th May 1937 | category: innovators | Hits: 3885
Guglielmo Marconi

Guglielmo Marconi born April 25, 1874 in Bologna son of wealthy Italian father and Irish mother.
Known to be very clever, Marconi was educated in Bologna in the lab of Augusto Righi, in Florence at the Istituto Cavallero, and, later, in Livorno.


Marconi had an interest in science and electricity. One of the scientific developments during this era came from Heinrich Hertz, who, beginning in 1888, demonstrated that one could produce and detect electromagnetic radiation—now generally known as "radio waves", at the time more commonly called "Hertzian waves" or "aetheric waves".


Hertz's death in 1894 brought published reviews of his earlier discoveries, and a renewed interest on the part of Marconi. He was permitted to briefly study the subject under Augusto Righi, a University of Bologna physicist and neighbour of Marconi who had done research on Hertz's work.


He repeated Heinrich Hertz's experiments and rapidly extended the range of detection. He mostly used his own self-built equipment in the attic of his home at the Villa Griffone in Pontecchio, Italy. His goal was to use radio waves to create a practical system of "wireless telegraphy" i.e. the transmission of telegraph messages without connecting wires as used by the electric telegraph.


Marconi is known to have improved wireless-telegraph system “kind of revolutioned it” He assembled and improved an array of facts, unified and adapted them to his system. Marconi's system had the following components:



  • A relatively simple oscillator, or spark producing radio transmitter, which was closely modeled after one designed by Righi, in turn similar to what Hertz had used;

  • A wire or capacity area placed at a height above the ground;

  •  A coherer receiver, which was a modification of Edouard Branly's original device, with refinements to increase sensitivity and reliability;

  • A telegraph key to operate the transmitter to send short and long pulses, corresponding to the dots-and-dashes of Morse code; and

  • A telegraph register, activated by the coherer, which recorded the received Morse code dots and dashes onto a roll of paper tape.


Moving out of doors in 1895, he introduced a transmitter sparking between an elevated aerial and earth. After increasing the length of the transmitter and receiver antennas, and arranging them vertically, and positioning the antenna so that it touched the ground, the range increased significantly. Soon he was able to transmit signals over a hill, a distance of approximately 1.5 kilometres (0.93 miles). By this point he concluded that with additional funding and research, a device could become capable of spanning greater distances and would prove valuable both commercially and militarily.


Marconi was unable to interest the Italian government in wireless, so in 1896 he went to England, where he aroused official interest and received support from the British Post Office.  While there, he gained the interest and support of William Preece, the Chief Electrical Engineer of the British Post Office.


A series of demonstrations for the British government followed—by March 1897, Marconi had transmitted Morse code signals over a distance of about 6 kilometres (3.7 miles) across the Salisbury Plain. On 13 May 1897, Marconi sent the first ever wireless communication over open sea. It transversed the Bristol Channel from Lavernock Point (South Wales) to Flat Holm Island, a distance of 6 kilometres (3.7 miles). The message read "Are you ready".  The receiving equipment was almost immediately relocated to Brean Down Fort on the Somerset coast, stretching the range to 16 kilometres (9.9 miles).


Impressed by these and other demonstrations, Preece introduced Marconi's ongoing work to the general public at two important London lectures: "Telegraphy without Wires", at the Toynbee Hall on 11 December 1896; and "Signaling through Space without Wires", given to the Royal Institution on 4 June 1897.
Marconi’s instrument helped him to demonstrate quickly, to 8 miles and then 25 miles and more. In 1899 signals across the English Channel, between Boulogne and Dover, caused a sensation, though the distance was less than that covered by other transmissions.


In 1900 Marconi determined to try sending wireless signals across the Atlantic, despite the theoretical conflict between rectilinear propagation of Hertz radiation and the curvature of the earth. He had, however, already received signals at 250-mile range. Using the Poldhu transmitter, an established station in southwestern England, and a temporary aerial supported by a kite on Signal Hill, St. John's, Newfoundland, nearly 1,800 miles away, he received the first transatlantic wireless signals on Dec. 12, 1901.


Also in 1901 Marconi patented his "four-circuit" tuning system. Thus multiplex wireless telegraphy became possible, and the interference of one signal with another was minimized. In 1902 Marconi patented a sensitive magnetic radiodetector to replace the coherer and, in 1905, the horizontal directional aerial, which at once brought improvements in signal strengths and allowed the development of long-distance commercial wireless.


After 1905 Marconi spent much of his time as an entrepreneur, surrounded by a talented staff of engineers and administrators, developing wireless telegraphy. Attempts to introduce a transatlantic wireless press service in 1903 had been premature, but in 1907 commercial communication was established between Marconi stations at Clifden in western Ireland and Glace Bay, Nova Scotia.


In 1914 Marconi was made a Senator in the Italian Senate and appointed Honorary Knight Grand Cross of the Royal Victorian Order in the UK. During World War I, Italy joined the Allied side of the conflict, and Marconi was placed in charge of the Italian military's radio service. He attained the rank of lieutenant in the Italian Army and of commander in the Italian Navy.


During World War I Marconi began experiments on shortwave radio and on aerials designed to transmit along narrow beams to minimize detection by an enemy. The year 1917 saw him as a member of the Italian mission to the United States on its entry into the war, and in 1919 he was a signatory to the Paris Treaty for Italy. He spent much of the next decade continuing the shortwave investigations begun in wartime, making useful discoveries, but none to compete with the great postwar expansion of the radio networks consequent on the development of radiotelephony and voice radio. He was hailed as the father of radio, but, especially in the United States, the real progress was made by a new generation.
Marconi joined the Italian Fascist party in 1923. In 1930, Italian dictator Benito Mussolini appointed him President of the Royal Academy of Italy, which made Marconi a member of the Fascist Grand Council.


Marconi died in Rome in 1937 at age 63 following a series of heart attacks, and Italy held a state funeral for him. As a tribute, all radio stations throughout the world observed two minutes of silence. His remains are housed in the Villa Griffone at Sasso Marconi, Emilia-Romagna, which assumed that name in his honour in 1938.


 


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