On This Day…

On the 6th October 1866 Reginald Fessenden was born in Canada

Fessenden was an early pioneer of AM radio/ wireless telephony.



  • In 1900 he discovered the radio-frequency alternator that produces AM signals.
  • In 1901 he discovered the hetrodyne principle (that when two radio signals are combined in a receiver, a third signal is created that is equal to the difference in the two received signals).
  • In 1904 he demonstrated the transmission of speech by modulating a radio wave and developed a depth finder using electromagnetic waves.
  • In 1906 he used his high frequency alternator to transmit voice and music via radio waves to ships at sea.
  • In 1907 together with Ernst Alexanderson he inverted a high frequency electric generator that produced radio waves with a frequency of 100 kHz. 

Roger So Far

The illustrated Corps Centenary book

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