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ABOUT WWVB
The NIST (National Institute of Standards and Technology—Time
and Frequency Division) radio station, WWVB, is located in Ft.
Collins, Colorado and transmits the exact time signal continuously
throughout the United States at 60 kHz. The signal can be
received up to 2,000 miles away through the internal antenna in the
Weather Station. However, due to the nature of the Earth’s
Ionosphere, reception is very limited during daylight hours. The
Weather Station will search for a signal every night when reception
is best. The WWVB radio station derives its signal from the NIST
Atomic clock in Boulder, Colorado. A team of atomic physicists
continually measure every second of every day to an accuracy of
ten billionths of a second a day. These physicists have created an
international standard, measuring a second as 9,192,631,770
vibrations of a Cesium 133 atom in a vacuum. For more
information about WWVB please see the NIST website at
http://www.boulder.nist.gov/timefreq/stations/wwvb.htm
