It was aired in the form of electromagnetic wave just half an hour ago from Easy 97.2 FM radio station in Athens.
La Solitudine - Laura Pausini
https://m.youtube.com/watch?v=B5Ouhzax96M
It sounded nice.
97.2MHz means electrons go up and down the transmiter antenna and therefore the receiver antenna 97.2 million times per second, ie 97 million and 200 thousand times in a second!
The song signal modulates this frequency up and down so that the carrier 97.2MHz can carry the music signal or information. If 97.2MHz were constant no information could be transmited. Like someone lifting a flag up and down at constant rate. No information is conveyed for information requires something unexpected to happen.
It is the instateneous change of carier frequency by the music signal that makes the music information transmission possible. It is Frequency Modulation hence the term FM. Effectively the song's electrical signal controls the vibrato of the radio station 97.2MHz carrier. The average still remains 97.2MHz.
This process creates frequency spectrum sidebands.
It is precisely these sidebands that make FM keyboard synthesizers such as the Yamaha DX7 have their rich tone. This is called FM synthesis and obviously both carrier and modulator are at audio band so that we can hear the tone of the keyboard musical synthesizer.
It is very likely that the electric piano sound of the song had been created by an FM synthesizer.
So there are at least 2 FM processes. One at the creation of the song, it's record production and one at radio FM transmission.
FM radio had been invented by Edwin Armstrong.
FM synthesis had been discovered (as he likes to use this term) by John Chowning.
Both patents had initially great difficulties on their acceptance.
John Chowning had lost his university job and Edwin Armstring had lost his life.
Now everybody uses them many times in a day.
Whose fault is it?
Perhaps nobody's.
It may have to do with how we perceive the world. A view that creates no anger is by one of the last Hellenic philosophers, Epictetous. Pity he is not taught at school or university but this is changing.
Reference:
Enchiridion - Epictetous
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