Trent Wolbe writes for The Verge: Before Facebook, before the internet, before cellphones and TV and even FM radio, there was AM radio.
Entire families would gather around elaborate refrigerator-sized receivers and bask in the warm glow of vacuum tubes as news, music, and entertainment poured from the only source of broadcast content in existence — NBC, ABC, and CBS were all on AM before they were on TV. Amplitude modulation operated at the very core of American culture.
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