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Guglielmo
Marconi was born in Bologna
on 25th April 1874, the son of an Italian country gentleman who
married a young Irish girl, Annie Jameson.Guglielmo
received no formal education, and showed little interest in his studies, except
in physics, and the course at technical school was not finished, but he studied
physics in Livorno at home of the Prof. Vincenzo Rosa.
At
the age of twenty the young genius began, as an amateur, experiments
which in about a year led to the invention of radiotelegraphy. These
experiments took place in the attic room of "Villa Griffone",
in Pontecchio, the country house of his father, in the borough of SASSO.
Following
the earlier mathematical work of Clerk Maxwell and the experiments of Heinrich
Hertz, Marconi realized a practical system of communicating intelligence without
the use of connecting wires. He first transmitted signals inside the attic
room, which, had a range of only a few meters. Then the distances
were increased, using a sensitive "coherer" in the receiver, in which
Marconi had an original mixture of powders. Batteries a bell were inserted in
series with the coherer. Guglielmo was persistent and experiments went on
throughout the winter of 1894, regardless of food or sleep. With
subsequent modifications Marconi progressively increased the range of
communication. In the spring of 1895 his experiments were transferred to
the garden, and it was here in the summer, that Marconi made his crucial
discoveries. By increasing the "capacity" of his equipment with the use
of sheet-iron slabs, the length of waves was brought from the original 40-80
cm to the band of high frequencies (about 50 m).
Thus
Marconi had invented the antenna-earth system. Signals were successfully
received at a distance of 2400 m, and finally , at the end of September,
transmission was obtained beyond a hill; this historical experiment
concluded with the famous rifle shot, celebrating the "birth of
radio".
Marconi's
invention was offered to the Ministry of Posts and Telegraphs in Roma; but they
politely declined.
On
the 12th February 1896 Guglielmo and his mother left for London,
to be received by his cousin Henry Jameson Davis.
Marconi
was introduced to William Preece, Engineer in Chief of the Post Office. The
invention gave rise to great interest and Mr. Preece offered the young Italian
full support, placing laboratories and engineers of the Post Office at Marconi's
disposal. A period of public demonstration began, each carefully prepared, with
great publicity. Marconi was followed in his experiments by crowds of curious
people and admirers.
Marconi
delivered lectures and had meetings with scientists, politicians and journalists.
He was received by Ministers, and later by Kings. He was soon to became very
popular, a front page man, loved by people all over the world, and grateful, in
view of the value of radio to human civilization and the safety of lives.
Marconi
registered his inventions but always allowed Italy to take free advantage of his
patents; he was a great patriot. In the sphere of application, each one of
Marconi's experiments represented a novelty, a stage in the progress of radio,
and a new record. After the demonstration at the Post Office, in
London, 1896 and Salisbury Plain 1896-1897, QRB 15 km; and the
Bristol Channel 1897, QRB 13 km; came the experiments in Roma and the
Gulf of La Spezia, July 1897, QRB 16 km.
In
1897 three stations were set up, at The Needles, Alum Bay, Isle of
Wight; at Bournemouth; then at the nearby village of Poole. A receiver
installed aboard a tug-boat could pick up signals at a distance of 30 km.
The
3rd June 1898 saw Marconi opening the first public commercial
radiotelegraph service between The Needles and Bournemouth, QRB 30 km.
Then
followed radiotelegraphy aboard ships and at a lighthouse; the commission of Lloyds
1898; the journalistic service at Kingstown Regatta 1898, QRB 36 km;
the station at Osborne House and the Royal Yacht 1898. In the same year
Marconi opened the world's first radio factory at Chelmsford, Essex. In
1899 the transmissions over the Channel, Vimereux-Dover 51 km; Vimereux-Harwich
and Chelmsford 130 km; and the Royal Navy exercises July 1899, QRB 140 km.
The
first trip to U.S.A. and the service at America's Cup, October 1899;
experiments for the American Navy; the transmissions between The Needles and
the Lizard 1900, QRB 300 km; the link France-Corsica, 1901.
It
was in Poldhu, near HELSTON, Cornwall, that in 1901,
Marconi constructed a big station of 25 kW which represented the last
word in the radio communication field for a number of years: tuned circuits were
employed and the antenna supported by towers of 69 m .
From
Poldhu came the famous "S" over the Atlantic to St. John's,
Newfoundland, 12th December 1901, QRB 3400 km; at Poldhu the messages to His
Majesty were received from Canada on 20th December 1902, QRB 4000 km; and from
U.S.A. 18th January 1903, QRB 5000 km. The news of the great conquest "the
first DX" was incredulous to many a renowned scientist, witness how much the
inventions were ahead of other researchers in the field.
Marconi
experimented with his apparatus aboard ships. From June to September 1902 tests
were made on the Italian warship "Carlo Alberto" from Italy to the North
Sea; then to Kronstadt, near St.Petersburg, and messages were exchanged with
Poldhu. At night time the signals reached beyond high mountains and over
the European Continent. Propagation was investigated by Marconi during
numerous trips; in his life he crossed the Atlantic 65 times ! In 1903,
during a trip to U.S.A. he received news from his stations in Europe and
America, and for the first time a daily news paper was printed aboard ship.
At
Poldhu many historical experiments were carried out, with the use of ever
new and revolutionary devices invented by Marconi; beam antennas and the
magnetic detector etc. until 1933, when the installation was
completely pulled down.
In
1907 the Marconi Company set up a new station at Clifden, Ireland,
with a power of 300 kW, using a new invention of the great man, the disc
discharger, and a new kind of beam antenna. Clifden handled
the traffic between the new and the old world, while Poldhu controlled
marine communication. For a long time the Marconi Company led the coasts
stations equipped with the Marconi system. In 1905 there were 110
war-ships and 70 merchant ships with 50 coast stations. By 1914, more
than 1500 ships. Numerous radio-beacons were set up by Marconi, and he had
invented a radio-compass.
In
addition to the Marconi Wireless Telegraph Company of England, other companies
were founded by Marconi in Argentina, U.S.A., France, Spain, Russia, Australia,
Belgium and Italy. Also, the International Marine Company and the Wireless Press
Company.
In
1912 the network of Marconi stations comprised Aden, Algeria, Australia,
Azores, Belgium, Brazil, Burma, China, Curacao, France, French Guyana, Germany,
India, Japan, Jamaica, Mexico, Morocco, Netherlands, Norway, Romania,
Russia, Senegal, South Africa, Sweden, Tobago, Trinidad, Uruguay, Zanzibar, and
4 stations in the Pacific Ocean and 13 stations in Italy.
The
contribution by Marconi and his assistants was great in the use of valves,
continuous waves, and radiotelephony. An absolute record was the conquest of
distance, that Marconi made in 1918, with transmissions from England
to Australia.
Big
stations with incredible powers were realized by the Marconi Company, at Rugby
in England, 1400 kW, and waves of 18700 m; Buenos Aires, 800 kW, 12000 and 16000
m .
Then
started the era of "broadcasting". The first station in England was
at Marconi's factory at Chelmsford, with the call 2MT; regular
programmes were transmitted in 1922. In the same year a broadcasting
station was born in London, 2LO installed at Marconi House in the Strand.
Marconi
showed great interest in HF from early times. In the period 1916-1926 he
investigated the propagation of those frequencies and proved the possibility
offered by HF to great distances and with low power. In 1919 he
bought a yacht of 72m called "Elettra", which became his laboratory
ship. In 1922 the cruise of Elettra in the Atlantic marked a turning
point of radio communication. Poldhu transmitted on the bands of 32,
47, 60 and 90 m, with a power of 12 kW or less. Marconi on the
Elettra at the Cape Verde Islands had incredible results. But signals
were received also in New York, Rio de Janeiro, Buenos Aires, Montreal and
Australia !
Elettra
arrived in New York and Marconi made his famous lecture to the American
Institute of Electrical Engineers, illustrating the properties of HF and
announcing a new system of short wave beam stations.
With
intuition, Marconi, once again had revolutionized the field of radio; he
signaled the end of the big stations of great power and low frequencies. All
this just when other companies, which always interfered with the work of Marconi,
were engaged in super-powered stations in LF. But the Italian genius was
to carry out his biggest accomplishment; The Imperial Wireless Scheme in HF
1926-1927, London, Cairo, Pretoria, Aden, Bangalore, Singapore, Glace Bay,
Buenos Aires, Cape Town, Calcutta, Sydney; The Portuguese Colonial Network,
Lisbon, Azores, Madeira, Cape Verde, Mozambique. Goa, Macao, Timor; and the
stations in Madrid and Argentina.
Well
known is the event of 26th March 1930 when Marconi sent out, from his
yacht in Genova, telegraphic impulses which switched on the lamps of the
Town Hall in Sydney 17 000 km.
On
12th October from Roma, Marconi illuminates the statue of the
Corcovado in Rio de Janeiro by the same method.
A
triumphal journey of Marconi took place, around the world, in 1933-1934.
On 2nd October 1933 the "Marconi Day" was celebrated in Chicago
at which the great man was present, and signals were transmitted around the
world, to rebound through his stations at New York, London, Roma, Bombay,
Manila, Honolulu, San Francisco and Chicago, in 3 minutes and 25 seconds.
Marconi
was decorated with the Nobel Prize for Physics in 1909 at the age of 35.
He received 15 degrees from different Universities; Senator of Italy; a
Marquis; President of the Italian Academy; President of C.N.R.; Professor of
Electromagnetic Waves at Roma University; Knight Grand Cross of the Royal
Victorian Order, by which he could be called Sir Guglielmo or Sir William.
Marconi
spent his last years in Italy, interested in the advanced field of
electromagnetic waves; microwaves, radiolocation, and medical applications
(Marconiterapia).
He
died in Roma on 20th July 1937.
At
an agreed time on the day after he died, the radio transmitters all over the
world closed down, simultaneously, for two minutes, in memory of the man
whose institutions and inventions had nullified distances with the conquest of
the aether.
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