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during daylight hours. The wireless weather station will search for a signal every night
when reception is best.
The WWVB radio station receives the time data from the NIST Atomic clock in Boulder,
Colorado. A team of atomic physicists is continually measuring every second, of every
day, to an accuracy of ten billionths of a second per 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 detail, visit http://www.boulder.nist.gov/timefreq.htm. To
listen to the NIST time, call (303)499-7111. This number will connect you to an
automated time, announced at the top of the minute in “Coordinated Universal Time”,
which is also known as Greenwich Mean Time (GMT). This time does not follow Daylight
Saving Time changes. After the top of the minute, a tone will sound for every second. It is
possible that your wireless weather station may not be exactly on the second due to the
variance in the quartz. However, the clock will adjust the quartz timing over the course of
several days to be very accurate; under 0.10 seconds per day.
