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Guglielmo Marconi: Application of Radio Waves to Communication, 1918

Electromagnetic Radiation

Heinrich Hertz experimentally confirmed Maxwell's prediction of electromagnetic radiation traveling at the speed of light. His Oscillator (transmitter) used the electric charge from a Leyden jar to create a spark between conductors and powerful electrical waves in the area around the spark.

The Hertz Resonator, consisting of separated conductors attached to copper sheets, completed the experiment by detecting radiation through the air from the sparking Oscillator. The quick electric surge of each spark created a changing electromagnetic radiation that induced an electric current in the Resonator.