Today in History; Nov. 30
Every minute on the minute, twenty-four hours a day, every day, a chime is heard and an unidentified male voice announces the time. This is the bulk of a day’s programming for radio station WWV, which operates on five radio bands: 2.5, 5, 10, 15 and 20 MHz. A ticking sound is also heard throughout the day; this sound is an audio version of a clock’s second hand. This audio clock is calibrated to the U.S. government’s atomic clocks so that anyone tuning in to WWV can set their own clocks by the radio broadcast.
WWV is the oldest continuously operated radio station in the United States; it was launched in May 1920. Its operations are a part of the National Institute of Standards and Technology, the branch of our government that measures things. Until 50 years ago today, the radio station and transmitter were headquartered in Maryland, but at precisely midnight December 1, 1966, WWV switched its broadcast to a new transmitter in Fort Collins, Colorado, a location that every device in America that sets its own time knows intimately. This new location brought the station transmitter so much closer to our nation’s atomic oscillators that its time measurements and announcements were brought ten times closer to true time.
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