Media, Information and Technoculture 2000F/G Lecture Notes - Lecture 6: Dxing, Erik Larsen, Canadian Content
22 Dec 2016
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Bi-directional: one to one: telegraph and telephone is bi-direction, telegraph takes way longer than telephone, first radio was original bi-directional (one message sent one message received) Uni-directional: by 1920s, radio became uni-directional, central transmitter to passive receivers (cid:862)(cid:271)road(cid:272)asti(cid:374)g(cid:863) One company communicating to a vast number of people. Radio waves: electro-magnetic energy, radiating in waves, circle at speed of light, travel hundreds of miles, first was 5 metres apart, sent as morse code (telegraph w/o the wires) Heinrich hertz (1888: lab experiments (cid:862)telegraph (cid:449)ithout (cid:449)ires(cid:863) (hertzian waves) Transmit electromagnetic waves (no longer wires, its through an atmosphere) Use morse code by sending messages through signals. Marconi wireless telegraph & signal co: trans-atlantic, first commercial service, signal hill: st. johns (newfoundland) sent trans landing signal which established sending wireless messages thousands of kms, he has a monopoly for radios. First voice transmission (cid:862) adiotelepho(cid:374)e(cid:863) (1900) influenced by alexander graham bell to do voice transmission.
