A Level >Radio< Digital Simple Receiver | Extras Non Exam Radio Simple TRF Superhet |
Radio |
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1842 - radio waves were observed but it took a long time for any scientist to realise that these waves might be useful.
1864 - James Clerk Maxwell worked out mathematical equations representing radio waves or electromagnetic radiation long before anyone transmitted or received a meaningful signal.
1895 - Marconi attempts to use radio for Telegraphy (Morse code).
1901 - Marconi made the first trans-Atlantic transmission.
1919 - The first AM voice/music transmission. Before this it was all Morse code or other keyed on/off transmissions.
1941 - The first commercial TV transmitter was established. Many experimental TV transmissions came before this.
1953 - The first non-experimental colour TV transmissions began.
1954 - The transistor became cheap enough for mass produced portable radios.
1962 - The first communications satellite.
1970 - Early fibre-optic communications.
1974 - The first computer network using wireless / radio was set up. This was ALOHAnet at the University of Hawaii.
1999 - Early WiFi.
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