Radio Waves

In 1887, Heinrich Rudolph Hertz, a German physicist, performed the first real-world experiments to demonstrate the theories of British physicist James Maxwell. Hertz proved that electricity could be transmitted through the air in electromagnetic waves and travel at the speed of light. This work laid the foundation for Guglielmo Marconi, an Italian electrical engineer, to invent a wireless telegraph system that he used in 1899 to send Morse Code messages across the English Channel. In 1906, Reginald Fessenden, a Canadian electrician and chemist, became the first person to broadcast human speech over radio waves.

By the 1920s, AM radios were commonplace in cars. In the late 1970s, companies such as IBM, HP, and Motorola began experimenting ...

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