Happy National Radio Day!! Many people contributed to the theory, inventions, and technology of what became radio. It’s generally recognized that Guglielmo Marconi made the first radio transmission from a temporary station on the Isle of Wight in 1895. The first public radio broadcast was made from the top of the Eiffel Tower in 1908. And here in the U.S., radio broadcasting began in 1910 when a program was produced from the Metropolitan Opera House in New York City.
Have you ever wondered why radio stations in the U.S. start with either K or W? Call letters predate the invention of radio, and were first used as part of landline telegraph communications. It was standard practice among telegraph operators to assign identifying letters to individual offices located along a line. Early radio stations employed former telegraph operators, who continued the practice. Today, all AM and FM stations are assigned their call letters by the FCC. International agreements determine the initial letters assigned to specific countries. In 1912, K and W were chosen at random for the U.S., and no particular reason was given for their selection. Since 1923, radio stations east of the Mississippi River start with W, and west of the river start with K.
The first car radio was introduced in 1922, but it was very large and took up too much space in the car. By the 1950s, car radios became more affordable and sleeker, and by the mid-60s, almost every new car came with a radio standard.
The origin of the term “disc jockey” goes back to 1935, when radio news commentator Walter Winchell used it to describe radio announcer Martin Block. It first appeared in print in a 1941 issue of Variety magazine.
In 1923, just 1% of U.S. households owned at least one radio receiver. By 1937, 75% did. Today, 68% of homes have at least one radio, and 82% of people 12 and older listen to terrestrial radio in a given week.
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