Guglielmo Giovanni Maria Marconi, (25 April 1874-20 July 1937) was an Italian inventor and electrical engineer, known for his creation of a practical radio wave-based wireless telegraph system. This led to Marconi being credited as the inventor of radio, 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.
In 1929, Marconi was ennobled as a Marchese (marquis) by King Victor Emmanuel III of Italy, and, in 1931, he set up Vatican Radio for Pope Pius XI.
Marconi was born into the Italian nobility as Guglielmo Giovanni Maria Marconi in Palazzo Marescalchi in Bologna on 25 April 1874, the second son of Giuseppe Marconi (an Italian aristocratic landowner from Porretta Terme) and his Irish 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).
Marconi had a brother, Alfonso, and a stepbrother, Luigi. Between the ages of two and six, Marconi and his elder brother Alfonso lived with their mother in the English town of Bedford.
More information: Heritage Newfoundland & Labrador
From youth, Marconi was interested in science and electricity. 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, based on the work of James Clerk Maxwell. At the time, this radiation was commonly called Hertzian waves, and is now generally referred to as radio waves.
There was a great deal of interest in radio waves in the physics community, but this interest was in the scientific phenomenon, not in its potential as a communication method. Physicists mainly looked on radio waves as an invisible form of light that could only travel along a line of sight path, limiting its range to the visual horizon like existing forms of visual signalling.
More information: NPS
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 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 other inventors did not seem to be pursuing.
At the turn of the 20th century, Marconi began investigating a means to signal across the Atlantic to compete with the transatlantic telegraph cables.
Marconi established a wireless transmitting station at Marconi House, Rosslare Strand, County Wexford, in 1901 to act as a link between Poldhu in Cornwall, England, and Clifden in Connemara, County 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 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 3,500 km.
More information: ETHW
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 sky wave 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.
More information: EWH
thought itself will be transmitted by radio.
Guglielmo Marconi
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