The first half century : milestones in radio

UNESCO Courier, Feb, 1997 by Bernard Blin

* Aleksandr S. Popov (Russia) invents the lightning-recording antenna. On 7 May he presents the first receiver of electromagnetic waves to the St. Petersburg Physical and Chemical Society.

* Near Bologna (Italy) Guglielmo Marconi carries out the first experimental transmission of wireless signals over a distance of 400, then 2,000 metres.

1896

* 2 June: In England, Marconi files a patent for a system of wireless communication, and later transmits and receives Morse code signals over a 3 km distance.

1897

* Eugene Ducretet (France) experiments with wireless telegraphy.

* Marconi founds the Wireless Telegraph and Signal Company, Ltd., in London.

* Karl Ferdinand Braun (Germany) invents a device which completes "the tuned circuit", matching the wavelength of transmitter and receiver, a procedure discovered by Sir Oliver Lodge (U.K.).

1898

* 5 November: Ducretet describes to the French Academy of Sciences transmissions between the Eiffel Tower and the Pantheon in Paris (4 km).

1899

* A 42-km link is established in France between two cruisers equipped with Ducretet-Popov devices.

* 28 March: Marconi makes a wireless transmission across the English Channel from Dover to Wimereux.

* Popov makes transmissions covering 50 km. from the shore to Russian ships.

1900

* Marconi obtains a patent for a process enabling an operator to select a wavelength. (The first receivers picked up all frequencies at the same time.) February: The first commercial wireless station is set up, on the island of Borkum (Germany).

1901

* 12 December: Marconi makes the first transatlantic wireless transmission, using Morse code, between Poldhu in Cornwall (U.K.) and St. John's, Newfoundland.

1903

* In Germany Siemens and Allgemeine Elektrizitats Gesellschaft create a joint affiliate, Telefunken.

* Valdemar Poulsen (Denmark) invents a means of producing continuous waves by "arc transmission", later used to construct high-frequency alternators for sending continuous radio waves.

* Gustave Ferrie sets up a long-distance telegraph station on the Eiffel Tower.

* The London Times and the New York Times receive information about the Russo-Japanese war via radio.

1904

* First experiments with telegraphic radio links in Spain.

* In France a commercial maritime radio network is set up under the control of the Ministry of Posts and Telegraphs.

* 16 November: John Fleming (U.K.) invents the thermionic two-electrode valve, or diode, making possible sound transmission.

* A radiotelegraphy station is built on the Adriatic coast in the principality of Montenegro.

1905

* In Canada, the Wireless Telegraph Act stipulates that a licence must be obtained for wireless telegraphy.

* First wireless communication in Spain, between El Ferrol del Caudillo and La Coruna.

* Discovery of the properties of galena (lead sulphide) as a detector of radio-electric signals.

1906

* Reginald Fessenden (U.S.A.) constructs a high-frequency alternator and succeeds in transmitting the human voice via radio.

* 25 October: Lee de Forest (U.S.A.) applies for a patent on the triode, a 3-electrode valve that makes possible the detection, transmission and amplification of radio signals.

1908

* 2 April: De Forest experiments with his triode in France by broadcasting from the Eiffel Tower.

1910

* 13 January: A broadcast from the Metropolitan Opera House in New York featuring Enrico Caruso is arranged by Lee de Forest and is heard 20 km away on a ship at sea.

1912

* 15 April: Radio amateurs pick up the SOS sent out by the Titanic.

1913

* Amateurs with galena-crystal radios listen in to the first regular weekly musical programmes broadcast from a wing of the Chateau de Laeken (Belgium).

* A federation of radio clubs, the Wireless Society of London (later the Radio Society of Great Britain) is founded in London.

1914

* March to August: a weekly concert is broadcast from the Chateau de Laeken (Belgium).

1915

* First international broadcasts, from Germany, of daily news reports.

* 25 October: The American Navy station in Arlington, Virginia(U.S.A.) establishes a link with the Eiffel Tower in Paris.

1917

* The Bolsheviks use radio to influence the Germans during negotiations for the Treaty of Brest-Litovsk.

* 8 November: A decree on the press establishes censorship that will last for 72 years in Russia.

1919

* 17 October: The Radio Corporation of America (RCA) is founded, absorbing the American subsidiary of the Marconi Company and amalgamating General Electric, Western Electric, AT&T (American Telephone and Telegraph) and Westinghouse.

* 16 November: In Germany Hans Bredow organizes political and economic news broadcasts for the press and industry.

* Many American radio amateurs receive on their crystal sets regular broadcasts from Pittsburgh (U.S.A.) by Frank Conrad. On Wednesday and Saturday evenings the station plays records chosen by the listeners. This marks the appearance of broadcasting as opposed to wireless telephony, where a connection is made from one point to another, between two correspondents.

1920

* Broadcasting on a regular daily basis was born in the United States.