Science Project - Maxwell had theoretically established that light consisted of electromagnetic waves, or at least that electromagnetic waves should Exist. However, most physicists were quite skeptical for several years about its actual existence. Experimental evidence was needed before Maxwell's theory as a whole could be accepted.
To test Maxwell's predictions it was necessary to invent some kind of device that could produce and detect electromagnetic waves, preferably others other than visible light. The first to achieve this was Heinrich Hertz, who developed a system similar to the one shown in this video, after casual observation.
The Coesor Brandy was one of the first Radio Frequency detectors invented in the early 20th century.
Its electrical resistance greatly decreases when it detects an electromagnetic pulse.
It is connected to an antenna, usually a dipole.
Its main disadvantage is the need for a small tap to turn it off and make it ready for a new electromagnetic pulse.
Basically it is composed of two electrodes mounted on an insulating tube with some metal filings between them.
In our experiment I used balls made of aluminum foil.