About the Invention of Radio

Radio has come a long way since original AM stations, first with the invention of FM radio stations. The most recent development is satellite radio, which are analog or digital radio signals that are sent out from one or more satellites. The satellite signal can be received in a larger geographical area when compared to traditional stations. Many scientists and a series of inventions lead to the development of radio.

Michael Faraday

In the late 1820’s and 1830’s, a physicist, Michael Faraday, experimented with electromagnetic induction. He concluded that to produce a current, a conductor had to break the lines of magnetic force. These experiments provided the foundation for radio, telephony, wireless telegraphy and television.  

James Clerk Maxwell 

Some scientists had realized the potential of wireless telegraphy, but could transmit for only a couple of miles in the late 1820’s based on the findings of Faraday. James Clerk Maxwell, a Scottish mathematician and physicist, built on the foundations of Michael Faraday's electromagnetic induction findings. He concluded that invisible electromagnetic waves spread and propagate similar to light and travel through a luminarious aether similar to ripples on a pond.

Heinrich Rudolf Hertz 

Heinrich Rudolf Hertz, a German physicist, believed that electromagnetic radiation was possible, but did not believe in the aether theory. In 1887, he used an induction coil, a capacitor and two spheres to discharge high voltage. This enabled the physicist to tune the oscillation enough to exude energy that was collected by a loop of wire with a spark gap, which confirmed the earlier findings of electromagnetic waves. The unit for electrical frequency was named “hertz,” which is one revolution per second. 

Guglielmo Marconi, Reginald Aubrey Fessenden, Charles Herrold and Other Scientists

Nicola Tesla, Oliver Joseph Lodge, Alexander Stepanovich Popov, Adolph Karl Heinrich Slaby and Jagadish Chandra Bose contributed findings that lead to the development of radio. Guglielmo Marconi built upon the coils and couplings designed by Karl Ferdinand Braun and the findings of Bose to send Morse code across the English Channel. Reginald Aubrey Fessenden conducted wireless transmissions of voice and music. Charles Herrold transmitted the first radio broadcasts licensed as KQW in 1921.