Hertz Discovery of Radio Waves

Hertz showed that radio waves are produced when high voltage sparks jump across an air gap and he showed that they could be detected with a wire loop with a small gap in it or a dipole detector.

He used a reflector to set up a stationary wave, which allowed him to calcualte the wavelength of the radiowaves.

He used a transmitter and a dipole detector to show that the radio waves could be polarised and were therefore transverse waves.

When the dipole detector was parallel to the trasmitter rods a maximum signal was detected.

When the dipole detector was perpendicular to the transmitter rods a zero signal was detected.