Heinrich Hertz gathered evidence in Karlsruhe to prove that electromagnetic rays expand in free space. To that end, he had to generate the waves necessary to verify his experiment. For this purpose, he developed the first transmitter, a “Hertz dipole with sphere gap”. A frame aerial was used to receive waves. He was thus able to translate theory into practice, becoming the founding father of radio in the process.

Radio is still one of the best-loved mass media, even if aerials and electromagnetic waves are steadily being replaced by digital technology.