Guglielmo Marconi
	Born: Died: Known for: Notable prizes:	April 25, 1874(1874-04-25) Palazzo Marescalchi, Bologna, Italy July 20, 1937 (aged 63)   Radio Nobel Prize for Physics (1909)

Early Years

Marconi was born near Bologna, Italy, the second son of Giuseppe Marconi, an Italian landowner, and his Irish wife, Annie Jameson, granddaughter of the founder of the Jameson Whiskey distillery. Marconi was educated in Bologna, Florence and, later, in Livorno.

During his early years, 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 who had done research on Hertz's work.

Marconi began to conduct experiments, building much of his own 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"’Äîi.e. the transmission of telegraph messages without connecting wires as used by the electric telegraph. This was not a new idea’Äînumerous investigators had been exploring wireless telegraph technologies for over 50 years, but none had proven commercially successful. Marconi did not discover any new and revolutionary principle in his wireless-telegraph system, but rather 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.

Similar configurations using spark-gap transmitters plus coherer-receivers had been tried by others, but many were unable to achieve transmission ranges of more than a few hundred metres. This was not the case for all researchers in the field of the wireless arts, though.

At first, Marconi could only signal over limited distances. In the summer of 1895 he moved his experimentation outdoors. 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. (Although Marconi may not have understood until later the reason, the "ground connections" allowed the earth to act as a waveguide resonator for the surface wave signal.) Soon he was able to transmit signals over a hill, a distance of approximately 1.5 kilometres (1 mile). 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.

Finding limited interest in his work in Italy, in early 1896 at the age of 21, Marconi traveled to London, England, accompanied by his mother to seek support for his work. (Marconi spoke fluent English in addition to Italian.) While there, he gained the interest and support of William Preece, the Chief Electrical Engineer of the British Post Office. The apparatus that Marconi possessed at that time was strikingly similar to that of one in 1882 by A. E. Dolbear, of Tufts College, which used a spark coil generator and a carbon granular rectifier for reception. A series of demonstrations for the British government followed’Äîby March, 1897, Marconi had transmitted Morse code signals over a distance of about 6 kilometres (4 miles) across the Salisbury Plain. On 13 May 1897, Marconi sent the first ever wireless communication over water. It transversed the Bristol Channel from Lavernock Point (South Wales) to Flat Holm Island, a distance of 14 kilometres (8.7 miles). The message read "Are you ready".

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 "Signalling through Space without Wires", given to the Royal Institute 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, Ireland, was conducted on 6 July 1898. The English channel was crossed on 27 March 1899, from Wimereux, France to South Foreland Lighthouse, England, and in the fall of 1899, the first demonstrations in the United States took place, with the reporting of the America's Cup international yacht races at New York. According to the Proceedings of the United States Naval Institute by the United States Naval Institute, the Marconi instruments were tested around 1899 and the tests concerning his wireless system found that the "[...] coherer, principle of which was discovered some twenty years ago, [was] the only electrical instrument or device contained in the apparatus that is at all new".

Marconi watching associates raise kite antenna at St. John's, December, 1901

Around the turn of the century, Marconi began investigating the means to signal completely across the Atlantic, in order to compete with the transatlantic telegraph cables. Marconi soon made the announcement that on 12 December 1901, using a 152.4 m (500 foot) kite-supported antenna for reception, the message was received at Signal Hill in St John's, Newfoundland (now part of Canada) signals transmitted by the company's new high-power station at Poldhu, Cornwall. The distance between the two points was about 3,500 kilometres (2,100 miles). Heralded as a great scientific advance, there was -- and continues to be -- some skepticism about this claim, partly because the signals had been heard faintly and sporadically. There was no independent confirmation of the reported reception, and the transmission, consisting of the Morse code letter S sent repeatedly were difficult to discern 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. The first stage operated at lower voltage and provided the energy for the second stage to spark at a higher voltage. Nikola Tesla, a rival in transalantic transmission, stated after being told of Marconi's reported transmission that "Marconi [... was] using seventeen of my patents."

Feeling challenged by skeptics, Marconi prepared a better organized 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 2,496 kilometres (1,551 miles), and audio reception up to 3,378 kilometres (2,099 miles). Interestingly, the maximum distances were achieved at night, and these tests were the first to show that for mediumwave and longwave transmissions, radio signals travel much farther at night than in the day. During the daytime, signals had only been received up to about 1,125 kilometres (700 miles), 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's belief they were essentially limited to line-of-sight distances.

On 17 December 1902, a transmission from the Marconi station in Glace Bay, Nova Scotia, Canada, became the first radio message to cross the Atlantic from North America. On 18 January 1903, a Marconi station built near Wellfleet, Massachusetts in 1901 sent a message of greetings from Theodore Roosevelt, the President of the United States, to King Edward VII of the United Kingdom, marking the first transatlantic radio transmission originating in the United States. 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 radiotelegraph service was finally announced in 1907, but even after this the company struggled for many years to provide reliable communication.

Titanic

The two radio operators aboard the Titanic were not employed by the White Star Line but by the Marconi International Marine Communication Company. Following the sinking of the ocean liner, survivors were rescued by the Carpathia. When it docked in New York, Marconi went aboard with a reporter from the New York Times. On 18 June 1912, Marconi gave evidence to the Court of Inquiry into the loss of the Titanic regarding the marine telegraphy's functions and the procedures for emergencies at sea.

Over the years, the Marconi companies gained a reputation for being technically conservative, in particular by continuing to use inefficient spark-transmitter technology, which could only be used for radiotelegraph operations, long after it was apparent that the future of radio communication lay with continuous-wave transmissions, which were more efficient and could be used for audio transmissions. Somewhat belatedly, the company did begin significant work with continuous-wave equipment beginning in 1915, after the introduction of the oscillating vacuum tube (valve). In 1920, employing a vacuum tube transmitter, the Chelmsford Marconi factory was the location for the first entertainment radio broadcasts in the United Kingdom’Äîone of these featured Dame Nellie Melba. In 1922 regular entertainment broadcasts commenced from the Marconi Research Centre at Writtle.