2. Press and release the + key a second time. The display will now show the
indoor humidity,
seconds and outdoor temperature.
3. Press and release the + key a third time. The display will now show the indoor humidity, indoor
temperature and seconds.
4. Press and release the + key a fourth time. The display will now return to the normal display
mode,
indoor humidity, indoor temperature and outdoor temperature
.
WWVB RADIO CONTROLLED TIME
The NIST 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 atomic clock. However, due to the nature of
the Earth’s Ionosphere, reception is very limited during daylight hours. The atomic clock 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
measures 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. This atomic clock regulates the WWVB transmitter.
Once the outdoor temperature is displayed on the atomic clock, the WWVB tower icon in the
clock display will start flashing in the top center of the LCD. This indicates that the clock has
detected a radio signal and is trying to receive it. When the time code is received, the WWVB
tower becomes permanently lit and the time will be displayed.
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