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- On the first International Telegraph Convention was signed by the 20 participating countries and the International Telegraph Union (later ITU) was set up to enable subsequent amendments to this initial agreement to be agreed upon - First practical wireless by Marconi, 'Hertzian Waves' over two miles! When he read about the experiments of Heinrich Hertz and about Popov's suggestion, he saw the possibility of using these waves as a means of signaling.
Duddell's arc would only oscillate at audio frequencies, audible to human hearing, and it was dubbed the "singing arc."In 1902 Valdemar Poulsen, succeeded in making the arc oscillate at the higher frequencies by using electrodes operating in a sealed chamber, with hydrocarbon vapor, and a strong magnetic field.
DX is an early telephone term for distant exchange.
It is also defined in Funk & Wagnall's as Distance.
The arc became the first transmitter capable of generating pure, undamped waves.
Arc transmitters were widely used at both shore stations and on ships.