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 and neighbour of Marconi who had done research on Hertz's work.
Marconi Rock, Salvan, Switzerland, site of 1895 experiments
Marconi began to conduct experiments, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio, Italy, with the help of his butler Mignani. 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. This was not a new idea—numerous investigators had been exploring wireless telegraph technologies for over 50 years, but none had proven technically and commercially successful. Marconi's system had the following components:
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.
Marconi, just twenty years old, began his first experiments working on his own with the help of his butler Mignani. In the summer of 1894, he built a storm alarm made up of a battery, a coherer, and an electric bell, which went off if there was lightning. Soon after he was able to make a bell ring on the other side of the room by pushing a telegraphic button on a bench.
One night in December, Guglielmo woke his mother up and invited her into his secret workshop and showed her the experiment he had created. The next day he also showed his work to his father, who, when he was certain there were no wires, gave his son all of the money he had in his wallet so Guglielmo could buy more materials.
In the summer of 1895 Marconi moved his experimentation outdoors and continued to experiment on his father's estate in Bologna. After increasing the length of the transmitter and receiver antennas, 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 2.4 kilometres (1.5 mi). 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 wrote to the Ministry of Post and Telegraphs, then under the direction of the honorable 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.
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 copyrights. 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; Marconi spoke fluent English in addition to Italian. Marconi arrived at Dover and at Customs the Customs officer opened his case to find various contraptions and 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 apparatus that Marconi possessed at that time was 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 plaque on the outside of BT Centre commemorates Marconi's first public transmission of wireless signals from that site. 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 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, 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 autumn 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.
Marconi sailed to the United States at the invitation of the New York Herald newspaper to cover the America's Cup races off Sandy Hook, NJ. The transmission was done aboard the SS Ponce, a passenger ship of the Porto Rico Line. Marconi left for England on 8 November 1899 on the American Line's SS St. Paul, and he and his assistants installed wireless equipment aboard during the voyage. On 15 November the St. 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 sixty-six 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 and Clifden in Co. Galway. He soon made the announcement that on 12 December 1901, using a 500-foot (150 m) 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 2,200 miles (3,500 km). Heralded as a great scientific advance, there was—and continues to be—considerable skepticism about this claim. The exact wavelength used is not known, but it is fairly reliably determined to have been in the neighborhood of 350 meters. The tests took place at a time of day during which the entire transatlantic path was in daylight. We now know (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 operating apparatus similar to that used by him to transmit the first wireless signal across the Atlantic Ocean, 1901
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 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 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 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 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 world's first radio message to cross the Atlantic from North America. In 1901, Marconi built a station near South Wellfleet, Massachusetts that on 18 January 1903 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. This station also was one of the first to receive the distress signals coming from the RMS Titanic. 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.
The two radio operators aboard the RMS Titanic—Jack Phillips and Harold Bride—were not employed by the White Star Line, but by the Marconi International Marine Communication Company. After the sinking of the ocean liner on 15 April 1912, survivors were rescued by the RMS Carpathia of the Cunard Line. Also employed by the Marconi Company was David Sarnoff, who would later head RCA. Wireless communications were reportedly maintained for 72 hours between Carpathia and Sarnoff, but Sarnoff's involvement has been questioned by some modern historians. When Carpathia docked in New York, Marconi went aboard with a reporter from The New York Times to talk with Bride, the surviving operator. On 18 June 1912, Marconi gave evidence to the Court of Inquiry into the loss of Titanic regarding the marine telegraphy's functions and the procedures for emergencies at sea. Britain's postmaster-general summed up, referring to the Titanic disaster, "Those who have been saved, have been saved through one man, Mr. Marconi...and his marvelous invention." Marconi was offered free passage on Titanic before she sank, but had taken Lusitania three days earlier. As his daughter Degna later explained, he had paperwork to do and preferred the public stenographer aboard that vessel.
Have I done the world good, or have I added a menace?
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 New Street Works factory in Chelmsford was the location for the first entertainment radio broadcasts in the United Kingdom, featuring Dame Nellie Melba. In 1922 regular entertainment broadcasts commenced from the Marconi Research Centre at Great Baddow, forming the prelude to the BBC.
Marconi died in Rome on 20 July 1937 at age 63, following a series of heart attacks, and Italy held a state funeral for him. As a tribute, shops on the street where he lived were "Closed for national mourning". In addition, at 6 pm the next day, the time designated for the funeral, all BBC transmitters and wireless Post Office transmitters in the British Isles observed two minutes of silence in his honor. The British Post Office also sent a message requesting that all broadcasting ships honor Marconi with two minutes of broadcasting silence as well. His remains are housed in the Villa Griffone at Sasso Marconi, Emilia-Romagna, which assumed that name in his honour in 1938.
In 1943, the Supreme Court of the United States handed down a decision on Marconi's radio patents restoring some of the prior patents of Oliver Lodge, John Stone Stone, and Nikola Tesla. The decision was not about Marconi's original radio patents and the court declared that their decision had no bearing on Marconi's claim as the first to achieve radio transmission, just that since Marconi's claim to certain patents were questionable, he could not claim infringement on those same patents. (There are claims the high court was trying to nullify a World War I claim against the U.S. government by the Marconi Company via simply restoring the non-Marconi prior patent.)
Marconi had a brother, Alfonso, and a stepbrother, Luigi.
On 16 March 1905, Marconi married the Hon. Beatrice O'Brien (1882–1976), a daughter of Edward O'Brien, 14th Baron Inchiquin, having met her in Poole in 1904. They had three daughters, Degna (1908–1998), Gioia (1916–1996), and Lucia (born and died 1906), and a son, Giulio, 2nd Marchese Marconi (1910–1971).
In 1913, the Marconis returned to Italy and became part of Rome society. Beatrice served as a lady-in-waiting to Queen Elena. The Marconis divorced in 1924, and, at Marconi's request, the marriage was annulled on 27 April 1927, so he could remarry. Beatrice Marconi married her second husband, Liborio Marignoli, Marchese di Montecorona, on 3 March 1924 and had a daughter, Flaminia.
On 12 June 1927 (religious 15 June), Marconi married Maria Cristina Bezzi-Scali (1900–1994), only daughter of Francesco, Count Bezzi-Scali. They had one daughter, Maria Elettra Elena Anna (born 1930), who married Prince Carlo Giovannelli (born 1942) in 1966; they later divorced. For unexplained reasons, Marconi left his entire fortune to his second wife and their only child, and nothing to the children of his first marriage.
Marconi wanted to personally introduce in 1931 the first radio broadcast of a Pope, Pius XI, and did announce at the microphone: "With the help of God, who places so many mysterious forces of nature at man's disposal, I have been able to prepare this instrument which will give to the faithful of the entire world the joy of listening to the voice of the Holy Father".
The premier collection of Marconi artifacts was held by The General Electric Company, p.l.c. (GEC) of the United Kingdom which later renamed Marconi plc and Marconi Corporation plc. In December 2004 the extensive Marconi Collection, held at the former Marconi Research Centre at Great Baddow, Chelmsford, EssexUK was donated to the nation by the Company via the University of Oxford. This consisted of the BAFTA award-winning MarconiCalling website, some 250+ physical artifacts and the massive ephemera collection of papers, books, patents and many other items. The artifacts are now held by The Museum of the History of Science and the ephemera Archives by the nearby Bodleian Library. The latest release, following three years work at the Bodleian, is the Online Catalogue to the Marconi Archives, released in November 2008.
The 'Marconi's Wireless Telegraph Company of Canada', of Montreal, Canada, was created in 1903 by Guglielmo Marconi. In 1925 the company was renamed to the 'Canadian Marconi Company', which was acquired by English Electric in 1953. The company name changed again to CMC Electronics Inc. (French: CMC Électronique) in 2001.
British patent No. 12,039 (1897) "Improvements in Transmitting Electrical impulses and Signals, and in Apparatus therefor". Date of Application 2 June 1896; Complete Specification Left, 2 March 1897; Accepted, 2 July 1897 (later claimed by Oliver Lodge to contain his own ideas which he failed to patent).
British patent No. 7,777 (1900) "Improvements in Apparatus for Wireless Telegraphy". Date of Application 26 April 1900; Complete Specification Left, 25 February 1901; Accepted, 13 April 1901.
British patent No. 5113 (1904) "Improvements in Transmitters suitable for Wireless Telegraphy". Date of Application 1 March 1904; Complete Specification Left, 30 November 1904; Accepted, 19 January August 1905.
British patent No. 21640 (1904) "Improvements in Apparatus for Wireless Telegraphy". Date of Application 8 October 1904; Complete Specification Left, 6 July 1905; Accepted, 10 August 1905.
British patent No. 14788 (1904) "Improvements in or relating to Wireless Telegraphy". Date of Application 18 July 1905; Complete Specification Left, 23 January 1906; Accepted, 10 May 1906.
^Bondyopadhyay, Prebir K. (1995). "Guglielmo Marconi – The father of long distance radio communication – An engineer's tribute". "25th European Microwave Conference, 1995". p. 879. doi:10.1109/EUMA.1995.337090.
^Bondyopadhyay, P.K. (1998). "Sir J.C. Bose diode detector received Marconi's first transatlantic wireless signal of December 1901 (the 'Italian Navy Coherer' Scandal Revisited)". Proceedings of the IEEE86: 259. doi:10.1109/5.658778.
Marconi's Wireless Telegraph Company, Year book of wireless telegraphy and telephony, London: Published for the Marconi Press Agency Ltd., by the St. Catherine Press / Wireless Press. LCCN 14017875 sn 86035439
Baker, W. J., A History of the Marconi Company, 1970.
Brodsky, Ira. "The History of Wireless: How Creative Minds Produced Technology for the Masses" (Telescope Books, 2008)
Cheney, Margaret, "Tesla: Man Out of Time" Laurel Publishing, 1981. Chapter 7, esp pp 69, re: published lectures of Tesla in 1893, copied by Marconi.
Clark, Paddy, "Marconi's Irish Connections Recalled," published in ";100 Years of Radio," IEE Conference Publication 411, 1995.
Coe, Douglas and Kreigh Collins (ills), Marconi, pioneer of radio, New York, J. Messner, Inc., 1943. LCCN 43010048
Garratt, G. R. M., The early history of radio: from Faraday to Marconi, London, Institution of Electrical Engineers in association with the Science Museum, History of technology series, 1994. ISBN 0-85296-845-0 LCCN gb 94011611
Geddes, Keith, Guglielmo Marconi, 1874–1937, London : H.M.S.O., A Science Museum booklet, 1974. ISBN 0-11-290198-0 LCCN 75329825 (ed. Obtainable in the U.S.A. from Pendragon House Inc., Palo Alto, California.)
Hancock, Harry Edgar, Wireless at sea; the first fifty years: A history of the progress and development of marine wireless communications written to commemorate the jubilee of the Marconi International Marine Communication Company, Limited, Chelmsford, Eng., Marconi International Marine Communication Co., 1950. LCCN 51040529 /L
Hong, Sungook, Wireless: From Marconi’s Black-Box to the Audio, Cambridge, Mass.: MIT Press, 2001. ISBN 0-262-08298-5.
Janniello, Maria Grace, Monteleone, Franco and Paoloni, Giovanni (eds) (1996), One hundred years of radio: From Marconi to the future of the telecommunications. Catalogue of the extension, Venice: Marsilio.
Jolly, W. P., Marconi, 1972.
Larson, Erik, Thunderstruck, New York: Crown Publishers, 2006. ISBN 1-4000-8066-5 A comparison of the lives of Hawley Harvey Crippen and Marconi. Crippen was a murderer whose Transatlantic escape was foiled by the new invention of shipboard radio.
MacLeod, Mary K., Marconi: The Canada Years – 1902–1946, Halifax, Nova Scotia: Nimbus Publishing Limited, 1992, ISBN 1551093308
Masini, Giancarlo, Guglielmo Marconi, Turin: Turinese typographical-publishing union, 1975. LCCN 77472455 (ed. Contains 32 tables outside of the text)
Mason, H. B. (1908). Encyclopaedia of ships and shipping, Wireless Telegraphy. London: Shipping Encyclopaedia. 1908.
Weightman, Gavin, Signor Marconi's magic box: the most remarkable invention of the 19th century & the amateur inventor whose genius sparked a revolution, 1st Da Capo Press ed., Cambridge, MA : Da Capo Press, 2003. ISBN 0-306-81275-4
Winkler, Jonathan Reed. Nexus: Strategic Communications and American Security in World War I. (Cambridge, MA: Harvard University Press, 2008). Account of rivalry between Marconi's firm and the U.S. government during World War I.