Guglielmo Marconi

Guglielmo Marconi
Born Guglielmo Giovanni Maria Marconi
(1874-04-25)25 April 1874
Palazzo Marescalchi, Bologna, Italy
Died 20 July 1937(1937-07-20) (aged 63)
Rome, Italy
Residence Italy
Nationality Italian
Alma mater University of Bologna
Academic advisors Augusto Righi
Known for Radio
Notable awards

Signature

Guglielmo Marconi, 1st Marquis of Marconi (Italian: [ɡuʎˈʎɛlmo marˈkoːni]; 25 April 1874 – 20 July 1937) was an Italian inventor and electrical engineer known for his pioneering work on long-distance radio transmission[1] and for his development of Marconi's law and a radio telegraph system. He is often credited as the inventor of radio,[2] and he shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun "in recognition of their contributions to the development of wireless telegraphy".[3][4][5]

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.[6][7] In 1929, the King of Italy ennobled Marconi as a Marchese (marquis).

Biography

Early years

Marconi was born into the Italian nobility as Guglielmo Giovanni Maria Marconi[8] 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[9]). 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.[10][11] After returning to Italy, and at the age of 18 University of Bologna physicist Augusto Righi, neighbour of Marconi who had done research on Heinrich Hertz's work, permitted Marconi to attend lectures at the university and use the lab and library as well.[12] Marconi received further education in Florence at the Istituto Cavallero and, later, in Livorno.[13] Marconi did not do well in school, according to Robert McHenry,[14] though historian Giuliano Corradi characterizes him in his biography as a true genius.[15] 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 Christina in 1927.[16]

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.[17]

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 which could only travel 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.[18] 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,[19] a line of inquiry that Marconi noted other inventors did not seem to be pursuing.[6]

Developing radio telegraphy

Marconi's first transmitter incorporating a monopole antenna. It consisted of an elevated copper sheet (top) connected to a Righi spark gap (left) powered by an induction coil (center) with a telegraph key (right) to switch it on and off to spell out text messages in Morse code.

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.[20] 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.[21][20] 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,[6] turning what was essentially a laboratory experiment into a useful communication system.[22] Marconi came up with a functional system with many components:[23]

In the summer of 1895, Marconi moved his experimentation outdoors and continued to experiment on his father's estate in Bologna. He tried different arrangements and shapes of antenna but even with improvements he was able to transmit signals only up to one half mile, a distance Oliver Lodge had predicted in 1894 as the maximum transmission distance for radio waves.

Transmission breakthrough

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.[24][25] 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.[26][27][28]

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.[29]

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

British Post Office engineers inspect Marconi's radio equipment during demonstration on Flat Holm Island, 13 May 1897. The transmitter is at center, 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.[30] 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".[31] 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, 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, New Jersey. The transmission was done aboard the SS Ponce, a passenger ship of the Porto Rico Line.[32] 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.

Transatlantic transmissions

Marconi watching associates raising the kite (a "Levitor" by B.F.S. Baden-Powell[33]) used to lift the antenna at St. John's, Newfoundland, December 1901
Magnetic detector by Marconi used during the experimental campaign aboard a ship in summer 1902, exhibited at the Museo nazionale della scienza e della tecnologia Leonardo da Vinci of Milan.

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. 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.[35][36]

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 Spy 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[37][38] between Clifden, Ireland and Glace Bay, but even after this the company struggled for many years to provide reliable communication to others.

Titanic

The role played by Marconi Co. wireless in maritime rescues raised public awareness of the value of radio and brought fame to Marconi, particularly the sinkings of the RMS Titanic on 15 April 1912 and the RMS Lusitania on 7 May 1915.

RMS Titanic radio operators 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.[39] Also employed by the Marconi Company was David Sarnoff, who later headed RCA. Wireless communications were reportedly maintained for 72 hours between Carpathia and Sarnoff,[40] 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.[39]

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.[41] 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 marvellous invention."[42] 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.[43]

Continuing work

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 be used only for radio-telegraph 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). The New Street Works factory in Chelmsford was the location for the first entertainment radio broadcasts in the United Kingdom in 1920, employing a vacuum tube transmitter and featuring Dame Nellie Melba. In 1922, regular entertainment broadcasts commenced from the Marconi Research Centre at Great Baddow, forming the prelude to the BBC, and he spoke of the close association of aviation and wireless telephony in that same year at a private gathering with Florence Tyzack Parbury, and even spoke of interplanetary wireless communication.

Later years

Marconi with his wife c. 1910

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. In 1929, he was made a marquess by King Victor Emmanuel III.

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 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".[45] 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 honour. The British Post Office also sent a message requesting that all broadcasting ships honour Marconi with two minutes of broadcasting silence as well.[45] His remains are housed in the Villa Griffone at Sasso Marconi, Emilia-Romagna, which assumed that name in his honour in 1938.[46][47]

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.[48][49] The decision was not about Marconi's original radio patents[50] 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.[51] There are claims the high court was trying to nullify a World War I claim against the United States government by the Marconi Company via simply restoring the non-Marconi prior patent.[48]

Personal life

American electrical engineer Alfred Norton Goldsmith and Marconi on 26 June 1922.

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.[52] 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.[53] Beatrice Marconi married her second husband, Liborio Marignoli, Marchese di Montecorona, on 3 March 1924 and had a daughter, Flaminia.[54]

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 (1942–2016) 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.[55]

Later in life, Marconi was an active Italian Fascist[56] and an apologist for their ideology and actions such as the attack by Italian forces in Ethiopia.

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".[57]

Legacy and honours

Honours and awards

Tributes

Guglielmo Marconi Memorial in Washington, D.C.

Places and organizations named after Marconi

Outer space

The asteroid 1332 Marconia is named in his honour. A large crater on the far side of the moon is also named after him.

Europe

Italy

Oceania

Australia

North America

Canada

As of 2016 the Canadian Marconi Company and CMC Electronics no longer exist. Most bought up by Esterline in Ottawa. The Marine Service Group was acquired by MacKay Marine but many of the employees left the group at transition.

United States
California
Massachusetts
New Jersey
New York
Pennsylvania

Patents

British patents

  • 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. 10245 (1902)
  • 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.

US patents

Reissued (US)

  • U.S. Patent RE11,913 "Transmitting electrical impulses and signals and in apparatus, there-for". Filed 1 April 1901; Issued 4 June 1901.

See also

References

  1. ↑ 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.
  2. ↑ Hong, p. 1
  3. 1 2 "Guglielmo Marconi: The Nobel Prize in Physics 1909". nobelprize.org
  4. ↑ 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 IEEE. 86: 259. doi:10.1109/5.658778.
  5. ↑ Roy, Amit (8 December 2008). "Cambridge 'pioneer' honour for Bose". The Telegraph. Kolkota. Retrieved 10 June 2010.
  6. 1 2 3 Icons of Invention: The Makers of the Modern World from Gutenberg to Gates. ABC-CLIO. 2009. p. 162. ISBN 978-0-313-34743-6.
  7. ↑ Mulvihill, Mary (2003). Ingenious Ireland: A County-by-County Exploration of the Mysteries and Marvels of the Ingenious Irish. Simon and Schuster. p. 313. ISBN 978-0-684-02094-5.
  8. ↑ Atti della Accademia di scienze, lettere e arti di Palermo: Scienze, Presso l'accademia, 1974, p. 11.
  9. ↑ Sexton, Michael (2005) Marconi: the Irish connection. Four Courts Press.
  10. ↑ Alfonso, not Guglielmo, was a pupil at Bedford School: 'It is not generally known that the Marconi family at one time lived in Bedford, in the house on Bromham Road on the western corner of Ashburnham Road, and that the elder brother of the renowned Marchese Marconi attended this School for four years.' The Ousel, June 1936, p. 78. From Alfonso's obituary.
  11. ↑ Bedfordshire Times. 23 July 1937, p. 9 (Marconi's obituary)
  12. ↑ Guglielmo Marconi (Fabrizio Bònoli, Giorgio Dragoni). Scienzagiovane.unibo.it. Retrieved on 10 June 2016.
  13. ↑ "Guglielmo Marconi and Early Systems of Wireless Communication" (PDF). Retrieved 15 February 2014.
  14. ↑ McHenry, Robert, ed. (1993). "Guglielmo Marconi". Encyclopædia Britannica.
  15. ↑ Corradi, Giuliano, "Guglielmo Marconi," Guglielmo Marconi. Tracce di un genio nel Tigullio, 2009.
  16. ↑ Marconi, Maria Christina (2001) Marconi My Beloved. Branden Books. pp. 19–24. ISBN 978-0-937832-39-4.
  17. ↑ "22. Word Origins". earlyradiohistory.us.
  18. ↑ Regal, Brian (2005) Radio: The Life Story of a Technology. Greenwood Publishing Group. p. 22. ISBN 0313331677
  19. ↑ Hong, p. 19
  20. 1 2 Brown, Antony. Great Ideas in Communications. D. White Co., 1969, page 141
  21. ↑ Guglielmo Marconi, padre della radio. Radiomarconi.com. Retrieved on 12 July 2012.
  22. ↑ Hong, p. 22
  23. ↑ Marconi delineated his 1895 apparatus in his Nobel Award speech. See: Marconi, "Wireless Telegraphic Communication: Nobel Lecture, 11 December 1909." Nobel Lectures. Physics 1901–1921. Amsterdam: Elsevier Publishing Company, 1967: 196–222. p. 198.
  24. ↑ Hong, pp. 20–22
  25. ↑ Marconi, "Wireless Telegraphic Communication: Nobel Lecture, 11 December 1909." Nobel Lectures. Physics 1901–1921. Amsterdam: Elsevier Publishing Company, 1967: 196–222. p. 206.
  26. ↑ The Saturday review of politics, literature, science and art, Volume 93. "THE INVENTOR OF WIRELESS TELEGRAPHY: A REPLY. To the Editor of the Saturday Review" Guglielmo Marconi and "WIRELESS TELEGRAPHY: A REJOINDER. To the Editor of the Saturday Review," Silvanus P. Thompson.
  27. ↑ Gualandi, Lodovico (26 June 2000). "MARCONI E LO STRAVOLGIMENTO DELLA VERITÀ STORICA SULLA SUA OPERA". radiomarconi.com.
  28. ↑ Proceedings of the Institution of Electrical Engineers, Volume 28 By Institution of Electrical Engineers. p. 294.
  29. ↑ Solari, Luigi (February 1948) "Guglielmo Marconi e la Marina Militare Italiana", Rivista Marittima
  30. ↑ "Flickr Photo".
  31. ↑ BBC Wales, Marconi's Waves at the Wayback Machine (archived 20 January 2007)
  32. ↑ Helgesen, Henry N. "Wireless Goes to Sea: Marconi's Radio and SS Ponce". Sea History (Spring 2008): 122.
  33. ↑ First Atlantic Ocean crossing by a wireless signal. Carnetdevol.org. Retrieved on 12 July 2012.
  34. ↑ Page, Walter Hines and Page, Arthur Wilson (1908) The World's Work. Doubleday, Page & Company. p. 9625
  35. ↑ "Marconi and the History of Radio". IEEE Antennas and Propagation Magazine. 46 (2): 130. 2004. doi:10.1109/MAP.2004.1305565.
  36. ↑ Belrose, John S. (5 September 1995) "Fessenden and Marconi: Their Differing Technologies and Transatlantic Experiments During the First Decade of this Century". International Conference on 100 Years of Radio.
  37. ↑ "The Clifden Station of the Marconi Wireless Telegraph System". Scientific American. 23 November 1907.
  38. ↑ Second Test of the Marconi Over-Ocean Wireless System Proved Entirely Successful. Sydney Daily Post. 24 October 1907.
  39. 1 2 Eaton, John P. and Haas, Charles A. (1994) Titanic – Triumph and Tragedy, A Chronicle in Words and Pictures. ISBN 0857330241.
  40. ↑ Herron, Edward A. (1969). Miracle of the Air Waves: A History of Radio. Messner. ISBN 0-671-32079-3.
  41. ↑ Court of Inquiry Loss of the S.S. Titanic 1912
  42. ↑ "Titanic's Wireless Connection". Wireless History Foundation. April 2012. Retrieved 7 October 2013.
  43. ↑ Daugherty, Greg (March 2012). "Seven Famous People Who Missed the Titanic". Smithsonian Magazine.
  44. ↑ William John (1972) History Of The Marconi Company 1874–1965. p. 296
  45. 1 2 "Radio falls silent for death of Marconi". Theguardian.com. Retrieved on 10 June 2016.
  46. ↑ VILLA GRIFFONE, NEAR BOLOGNA, ITALY. markpadfield.com
  47. ↑ Guglielmo Marconi at Find a Grave
  48. 1 2 Redouté, Jean-Michel; Steyaert, Michiel (2009). EMC of Analog Integrated Circuits. Springer Science & Business Media. p. 3. ISBN 978-90-481-3230-0.
  49. ↑ Meadow, Charles T. (2002). Making Connections: Communication through the Ages. Scarecrow Press. p. 193. ISBN 978-1-4617-0691-5.
  50. ↑ White, Thomas H. (1 November 2012). "Nikola Tesla: The Guy Who DIDN'T "Invent Radio". Earlyradiohistory.us.
  51. ↑ Sobot, Robert (2012). Wireless Communication Electronics: Introduction to RF Circuits and Design Techniques. Springer Science & Business Media. p. 4. ISBN 978-1-4614-1116-1.
  52. ↑ Padfield, Mark. "Beatrice O'Brien". Marconi Calling.
  53. ↑ Marconi, Degna (2001) My Father, Marconi. Guernica Editions. pp. 218–227. ISBN 1550711512.
  54. ↑ Kelly's Handbook to the Titled, Landed, and Official Classes (Kelly's, 1969), p. 623
  55. ↑ Degna Marconi (2001), My Father, Marconi (Guernica Editions), p. 232. ISBN 1550711512.
  56. ↑ Physicsworld.com, "Guglielmo Marconi: radio star", 2001 Archived 14 July 2007 at the Wayback Machine.
  57. ↑ "80 Years of Vatican Radio, Pope Pius XI and Marconi. .. and Father Jozef Murgas?". Saint Benedict Center.
  58. ↑ National Broadcasters Hall of Fame. Accessed 10 February 2009
  59. ↑ "Pioneer: Guglielmo Marconi". radiohof.org. Retrieved 30 May 2012.
  60. ↑ Italy 2000 lira banknote (1990) Banknote Museum (banknote.ws). Retrieved on 17 March 2013.
  61. ↑ "Milestones:Marconi's Early Wireless Experiments, 1895". IEEE Global History Network. IEEE. Retrieved 29 July 2011.
  62. ↑ "List of IEEE Milestones". IEEE Global History Network. IEEE. Retrieved 29 July 2011.
  63. ↑ New Jersey to Bon Jovi: You Give Us a Good Name. accesshollywood.com (2 February 2009).
  64. ↑ UK | England | Berkshire | Marconi archives move to Oxford. BBC News (6 December 2004). Retrieved on 2016-06-10.
  65. ↑ Catalogue of the Marconi Archive now available online. bodleian.ox.ac.uk (7 November 2008)
  66. 1 2 "CMC Electronics' Profile". CMC Electronics Inc. Retrieved 12 January 2007.
  67. ↑ "Chatham Marconi Maritime Center". www.arrl.org. Retrieved 9 November 2015.

Sources

Further reading

Relatives and company publications
Other
Wikimedia
General achievements
Foundations and academics
Multimedia and books
Transatlantic "signals" and radio
Keys and "signals"
Priority of invention

vs Tesla

Personal
Other
Academic offices
Preceded by
Jan Smuts		 Rector of the University of St Andrews
1934–1937 		Succeeded by
Robert MacGregor Mitchell
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