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Guglielmo Marconi, an Italian inventor and electrical engineer


Guglielmo Marconi, was an Italian inventor and electrical engineer known for his pioneering work on long-distance radio transmissionand for his development of Marconi’s law and a radio telegraph system. He is credited as the inventor of radio,[7] and he shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun “in recognition of their contributions to the development of wireless telegraphy”.

Marconi was also an entrepreneur, businessman, and founder of The Wireless Telegraph & Signal Company in the United Kingdom in 1897 (which became the Marconi Company). He succeeded in making an engineering and commercial success of radio by innovating and building on the work of previous experimenters and physicists. In 1929, Marconi was ennobled as a Marchese (marquis) by King Victor Emmanuel III of Italy and, in 1931, he set up the Vatican Radio for Pope Pius XI.

Marconi was born into the Italian nobility as Guglielmo Giovanni Maria Marconi in Bologna on 25 April 1874, the second son of Giuseppe Marconi (an Italian aristocratic landowner from Porretta Terme) and his Irish/Scot wife Annie Jameson (daughter of Andrew Jameson of Daphne Castle in County Wexford, Ireland and granddaughter of John Jameson, founder of whiskey distillers Jameson & Sons). Between the ages of two and six, Marconi and his elder brother Alfonso were brought up by his mother in the English town of Bedford.After returning to Italy, and at the age of 18 Marconi became a neighbour of University of Bologna physicist Augusto Righi, who had done research on Heinrich Hertz’s work. Righi permitted Marconi to attend lectures at the university and also to use the University’s laboratory and library.Marconi received further education in Florence at the Istituto Cavallero and, later, in Livorno.[not in citation given] Marconi did not do well in school, according to Robert McHenry, though historian Giuliano Corradi characterizes him in his biography as a true genius.[20] He was baptised as a Catholic but had been brought up as a member of the Anglican Church, being married into it (although this marriage was later annulled). Marconi was confirmed in the Catholic faith and became a devout member of the Church before his marriage to Maria Cristina in 1927.

Radio work
During his early years, Marconi had an interest in science and electricity and in the early 1890s he began working on the idea of “wireless telegraphy”—i.e., the transmission of telegraph messages without connecting wires as used by the electric telegraph. This was not a new idea; numerous investigators and inventors had been exploring wireless telegraph technologies and even building systems using electric conduction, electromagnetic induction and optical (light) signalling for over 50 years, but none had proven technically and commercially successful. A relatively new development came from Heinrich Hertz, who in 1888 demonstrated that one could produce and detect electromagnetic radiation, at the time commonly called “Hertzian” waves, and now generally referred to as radio waves.

There was a great deal of interest in radio waves in the physics community, but the interest was in radio as a scientific phenomenon, not in its potential as a communication method. Physicists generally looked on radio waves as an invisible form of light, a short range phenomenon that could travel only along a line of sight path, and thus its range was limited to the visual horizon like existing forms of visual signaling, making it unsuitable for long distance communication. Hertz’s death in 1894 brought published reviews of his earlier discoveries including a demonstration on the transmission and detection of radio waves by the British physicist Oliver Lodge and an article about Hertz’s work by Marconi’s teacher, Augusto Righi. Righi’s article renewed Marconi’s interest in developing a wireless telegraphy system based on radio waves, a line of inquiry that Marconi noted that other inventors did not seem to be pursuing.

Marconi, then twenty years old, began to conduct experiments in radio waves, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio (now an administrative subdivision of Sasso Marconi), Italy with the help of his butler Mignani. He built on Hertz’s original experiments and, at the suggestion of Righi, began using a coherer, an early detector based on the 1890 findings of French physicist Edouard Branly and used in Lodge’s experiments, that changed resistance when exposed to radio waves. In the summer of 1894, he built a storm alarm made up of a battery, a coherer, and an electric bell, which went off when it picked up the radio waves generated by lightning.

He continued to work in the attic. Late one night in December 1894 he demonstrated a radio transmitter and receiver to his mother, a set-up that made a bell ring on the other side of the room by pushing a telegraphic button on a bench.Financed by his father, Marconi continued to read through the literature and picked up on the ideas of physicists who were experimenting with radio waves, but did a great deal to develop devices, such as portable transmitters and receiver systems, that could work over long distances, turning what was essentially a laboratory experiment into a useful communication system. Marconi came up with a functional system with many components:

A breakthrough came that summer when Marconi found that much greater range could be achieved after he raised the height of his antenna and, borrowing from a technique used in wired telegraphy, grounding his transmitter and receiver. With these improvements the system was capable of transmitting signals up to 2 miles (3.2 km) and over hills.[29][30] The monopole antenna reduced the frequency of the waves compared to the dipole antennas used by Hertz, and radiated vertically polarized radio waves which could travel longer distances. By this point, he concluded that a device could become capable of spanning greater distances, with additional funding and research, and would prove valuable both commercially and militarily. Marconi’s experimental apparatus proved to be the first engineering-complete, commercially successful radio transmission system.[31][32][33]

Marconi wrote to the Ministry of Post and Telegraphs, then under the direction of Pietro Lacava, explaining his wireless telegraph machine and asking for funding. He never received a response to his letter, which was eventually dismissed by the Minister, who wrote “to the Longara” on the document, referring to the insane asylum on Via della Lungara in Rome.[34]

In 1896, Marconi spoke with his family friend Carlo Gardini, Honorary Consul at the United States Consulate in Bologna, about leaving Italy to go to England. Gardini wrote a letter of introduction to the Ambassador of Italy in London, Annibale Ferrero, explaining who Marconi was and about these extraordinary discoveries. In his response, Ambassador Ferrero advised them not to reveal the results until after they had obtained the patents. He also encouraged him to come to England where he believed it would be easier to find the necessary funds to convert the findings from Marconi’s experiment into a practical use. Finding little interest or appreciation for his work in Italy, Marconi travelled to London in early 1896 at the age of 21, accompanied by his mother, to seek support for his work. (He spoke fluent English in addition to Italian.) Marconi arrived at Dover and the Customs officer opened his case to find various apparatus. The customs officer immediately contacted the Admiralty in London. While there, Marconi gained the interest and support of William Preece, the Chief Electrical Engineer of the British Post Office.

The British become interested

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British Post Office engineers inspect Marconi’s radio equipment during demonstration on Flat Holm Island, 13 May 1897. The transmitter is at centre, the coherer receiver below it, the pole supporting the wire antenna is visible at top.
Marconi made his first demonstration of his system for the British government in July 1896.[35] A further series of demonstrations for the British followed—by March 1897, Marconi had transmitted Morse code signals over a distance of about 6 kilometres (3.7 mi) across Salisbury Plain. On 13 May 1897, Marconi sent the world’s first ever wireless communication over open sea. The experiment, based in Wales, witnessed a message transversed over the Bristol Channel from Flat Holm Island to Lavernock Point in Penarth, a distance of 6 kilometres (3.7 mi). The message read “Are you ready”. The transmitting equipment was almost immediately relocated to Brean Down Fort on the Somerset coast, stretching the range to 16 kilometres (9.9 mi).

Plaque on the outside of BT Centre commemorates Marconi’s first public transmission of wireless signals.
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.

Numerous additional demonstrations followed, and Marconi began to receive international attention. In July 1897, he carried out a series of tests at La Spezia, in his home country, for the Italian government. A test for Lloyds between Ballycastle and Rathlin Island, Northern Ireland, was conducted on 6 July 1898. The English channel was crossed on 27 March 1899, from Wimereux, France to South Foreland Lighthouse, England. Marconi set up an experimental base at the Haven Hotel, Sandbanks, Poole Harbour, Dorset, where he erected a 100-foot high mast. He became friends with the van Raaltes, the owners of Brownsea Island in Poole Harbour, and his sailing boat, the Elettra, was often moored on Brownsea or at the Haven Hotel, when he was not conducting experiments at sea.

In December 1898, the British lightship service authorized the establishment of wireless communication between the South Foreland lighthouse at Dover and the East Goodwin lightship, twelve miles distant. On 17 March 1899 the East Goodwin lightship sent a signal on behalf of the merchant vessel Elbe which had run aground on Goodwin Sands. The message was received by the radio operator of the South Foreland lighthouse, who summoned the aid of the Ramsgate lifeboat.

In the autumn of 1899, the first demonstrations in the United States took place. Marconi had sailed to the U.S. at the invitation of the New York Herald newspaper to cover the America’s Cup international yacht races off Sandy Hook, New Jersey. The transmission was done aboard the SS Ponce, a passenger ship of the Porto Rico Line.[39] Marconi left for England on 8 November 1899 on the American Line’s SS Saint Paul, and he and his assistants installed wireless equipment aboard during the voyage. On 15 November Saint Paul became the first ocean liner to report her imminent return to Great Britain by wireless when Marconi’s Royal Needles Hotel radio station contacted her 66 nautical miles off the English coast.

At the turn of the 20th century, Marconi began investigating the means to signal completely across the Atlantic in order to compete with the transatlantic telegraph cables. Marconi established a wireless transmitting station at Marconi House, Rosslare Strand, Co. Wexford in 1901 to act as a link between Poldhu in Cornwall, England and Clifden in Co. Galway, Ireland. He soon made the announcement that the message was received at Signal Hill in St John’s, Newfoundland (now part of Canada) on 12 December 1901, using a 500-foot (150 m) kite-supported antenna for reception—signals transmitted by the company’s new high-power station at Poldhu, Cornwall. The distance between the two points was about 2,200 miles (3,500 km). It was heralded as a great scientific advance, yet there also was—and continues to be—considerable scepticism about this claim. The exact wavelength used is not known, but it is fairly reliably determined to have been in the neighbourhood of 350 meters (frequency ≈850 kHz). The tests took place at a time of day during which the entire transatlantic path was in daylight. It is now known (although Marconi did not know then) that this was the worst possible choice. At this medium wavelength, long distance transmission in the daytime is not possible because of heavy absorption of the skywave in the ionosphere. It was not a blind test; Marconi knew in advance to listen for a repetitive signal of three clicks, signifying the Morse code letter S. The clicks were reported to have been heard faintly and sporadically. There was no independent confirmation of the reported reception, and the transmissions were difficult to distinguish from atmospheric noise. A detailed technical review of Marconi’s early transatlantic work appears in John S. Belrose’s work of 1995. The Poldhu transmitter was a two-stage circuit.

Marconi demonstrating apparatus he used in his first long distance radio transmissions in the 1890s. The transmitter is at right, the receiver with paper tape recorder at left.

Marconi caricatured by Leslie Ward for Vanity Fair, 1905
Feeling challenged by skeptics, Marconi prepared a better organised and documented test. In February 1902, the SS Philadelphia sailed west from Great Britain with Marconi aboard, carefully recording signals sent daily from the Poldhu station. The test results produced coherer-tape reception up to 1,550 miles (2,490 km), and audio reception up to 2,100 miles (3,400 km). The maximum distances were achieved at night, and these tests were the first to show that radio signals for medium wave and longwave transmissions travel much farther at night than in the day. During the daytime, signals had been received up to only about 700 miles (1,100 km), less than half of the distance claimed earlier at Newfoundland, where the transmissions had also taken place during the day. Because of this, Marconi had not fully confirmed the Newfoundland claims, although he did prove that radio signals could be sent for hundreds of kilometres, despite some scientists’ belief that they were limited essentially to line-of-sight distances.

On 17 December 1902, a transmission from the Marconi station in Glace Bay, Nova Scotia, Canada became the world’s first radio message to cross the Atlantic from North America. In 1901, Marconi built a station near South Wellfleet, Massachusetts that sent a message of greetings on 18 January 1903 from United States President Theodore Roosevelt to King Edward VII of the United Kingdom. However, consistent transatlantic signalling was difficult to establish.

Marconi began to build high-powered stations on both sides of the Atlantic to communicate with ships at sea, in competition with other inventors. In 1904, a commercial service was established to transmit nightly news summaries to subscribing ships, which could incorporate them into their on-board newspapers. A regular transatlantic radio-telegraph service was finally begun on 17 October 1907 between Clifden, Ireland and Glace Bay, but even after this the company struggled for many years to provide reliable communication to others.

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