English: This is a full drawing by Hertz about his setup on the experiment of EM waves published in 1888.
A, A' are two metal plates of 40cm in the side, used as the capacitors. They are connected by wire with a gap in the middle. When the AA' are charged up through the induction coil J, the high voltage will produce sparks in the gap. Thus it generates electromagnetic waves. This part of the experimental setup can be seen as the radio wave transmitter.
Square wire B and circle wire C are receiving circuits. They both have spark-gaps. Hertz adjusted them to be in resonance state with the EM wave generator.
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ON THE FINITE VELOCITY OF PROPAGATION OF ELECTROMAGNETIC ACTIONS
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