Many of us take the radio for granted. But the concept of being able to listen to music over the radio has only been a phenomenon of this century. And radio on the Internet even newer.

The radio itself and its technology came about due to the contribution of numerous people and their inventions over the years. There are varying disputed claims about who invented radio, which in the beginning was called “wireless telegraphy”. Names like Marconi, Tesla, and more come to mind when one thinks of this phenomena. Marconi first equipped ships with lifesaving wireless communications and established the first transatlantic radio service while Tesla developed means to reliably produce radio frequency electrical currents, publicly demonstrated the principles of radio, and transmitted long distance signals.

It wasn’t until 1904 that the U.S. Patent Office awarded Marconi a patent for the invention of radio, possibly influenced by Marconi’s financial backers in the States, who included Thomas Edison and Andrew Carnegie. This also allowed the U.S. government (among others) to avoid having to pay the royalties that were being claimed by Tesla for use of his patents.

The invention of AM radio or amplitude-modulated came from Reginald Fessenden and Lee de Forest. Having AM radio allowed radios to transmit more than one station. An AM receiver detects amplitude variations in the radio waves at a particular frequency. It then amplifies changes in the signal voltage to drive a loudspeaker or earphones. Fessenden gave his first broadcast on Christmas Eve of 1906 and used the concept of AM radio to transmit small-scale voice and music broadcasts up until World War I.

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