| THE HISTORY OF RADIO PART 1 |
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Have you ever wondered who developed Radio? This is the tale of the pioneers behind The History of Radio.
Michael Faraday and Joseph Henry had individually developed the theory that a current flowing in one wire could induce a current in another wire that was not physically connected to the first. In 1873 English Telegrapher Louis May, discovered the electrical resistance of selenium was lowered when the material was illuminated. In 1864 Scotsman James Clerk Maxwell published his first paper that showed by theoretical reasoning that an electrical disturbance resulting from a change in an electrical quantity, such as voltage or current, should propagate through space at the speed of light.
On the 21st July 1866 Dr Mahlon Loomis of Washington D.C. described a system of signalling by radio. Dr Loomis demonstrated his system by conveying messages over a distance of 14 miles between Catochin Ridge and Bears Den in Loudoun County, Virgina. US Senator Samuel C. Pomeroy of Kansas and US Representative John A. Binham of Ohio witnessed the demonstration.
During the late 1880’s Heinrich Hertz produced electromagnetic waves. He used oscillating circuits made from combinations of capacitors and inductors, to transmit and receive radio waves. By measuring the wavelength (designated by the Greek lower-case letter lambda) of the waves and knowing the frequency of oscillation (f), he was able to calculate the velocity (v) of the waves using the equation v = f x (lambda). In this way he verified Maxwell's theoretical prediction that electromagnetic waves travel at the speed of light.
In 1892 Nathan B. Stubblefield demonstrated the first radio transmission of the human voice. Guglielmo Marconi produced the first practical wireless telegraph system in Bologna, Italy in 1895. Marconi offered his telegraph system to the Italian Government, but they turned it down. In 1896 Marconi moved to London and commenced working for the Post Office, after being introduced to them by Mr. A. A. Campbell-Swinton. Marconi received the first wireless patent from the British Government. In part, it was based on the theory that communication range increases substantially as the height of the aerial above ground level increases. On the 12th December Marconi gave the first public demonstration of radio at Toynbee Hall, London.
In July 1897 Guglielmo Marconi opened the "Wireless Telegraph and Signal Company". This is the company that Marconi used to carry out all his offshore radio tests. In November The first permanent radio installation "Needles Hotel Wireless Station" was installed at Alum Bay, Isle of Wight by the Wireless Telegraph and Signal Company.
In 1898 Marconi set up radio equipment on the Royal Yacht Osbourne which was moored at Cowes, Isle of Wight, and in Osbourne house, also in the Isle of Wight. 150 messages were passed between Queen Victoria and Edward, (Prince of Wales, who later became King Edward VII). The Prince operated the equipment on the Royal Yacht while Marconi operated the equipment in Osbourne house.
In 1899 Captain Jackson, on board the HMS Defiant (an old wooden battle ship which had been converted into a Royal Navy torpedo school) gave orders to three cruisers in controlled manoeuvres, via radio for the first time. Marconi was on board as an observer. On the 27th March the first wireless telegraph message was sent across the English Channel (South Foreland, UK to Wimereux, France) by Marconi. The success of the demonstration resulted in lighthouses throughout the UK being fitted with wireless sets.
In November 1901 Marconi first attempted to send radio broadcasts across the Atlantic. The test failed when one of 2 balloons holding 600 feet of aerial wire broke it's mooring and floated away. On the 12th December Marconi received the first transatlantic communication, which involved sending the Morse-code signal for the letter "S", from Poldhu, Cornwall, England, to Signal Hill, Saint John's, Newfoundland. The aerial, 600 feet of wire, was held aloft by 6 kites flying at an altitude of 400 feet.
In 1905 Sir Ambrose Fleming invented the "diode valve" which permitted the detection of high-frequency radio waves. On the 24th December Professor Reginald Aubrey Fessenden’s National Electric Signalling Company at Brant Rock, Massachusetts, is credited as the first radio station when Reginald Aubrey spoke by radio to ships in the Atlantic Ocean.
In 1907 The British Admiralty authorised Lieutenant Quentin Crauford to set up an experimental radio station on board HMS Andromeda and to broadcast a programme for the benefit of the Royal Navy fleet in Chatham dockyard. American Lee De Forest invented the "audion" now known as the "triode valve" which was able to amplify radio and sound waves. In February the first regular experimental radio broadcasts were made by Lee De Forest Radio Telephone Company, from the top floor of the Parker Building on Fourth Avenue, New York.
In 1910 Charles D. Herrold commenced a daily schedule of radio broadcasts from his "School of Radio" housed in the City bank building at San José, California. In 1918 American Edwin Armstrong invented the Superheterodyne radio circuit.
In 1919 American Marconi, the US subsidiary of Marconi's successful British company, was bought by the newly formed Radio Corporation of America (RCA). Also in 1919 KDKA, an experimental radio station in America broadcast the first music programme designed to be listened to by an audience. In 1920 Marconi purchased the yacht SY Rovenska, and renamed it "Elettra". The yacht was fitted with radio equipment and was given the call sign 1CCM. When the Imperial Press Union went to Canada on the steam ship "Victorian" he made use of the trip to experiment with high power long wave broadcasts and low power short wave broadcasts to determine which was the best system for long distance broadcasting. On the 23rd February Marconi's company in Chelmsford, UK, commenced one hour test broadcasts consisting of songs and music each evening under the call sign of 2MT, usually referred to as "2 Emma Writtle". The tests last 14 days. In November Marconi's company, 2MT was forced to suspend their experimental broadcasts after complaints of interference to aircraft and ship radio communications.
Guglielmo Marconi
An early example of a Radio
