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Radio Controlled WWVB Clock
The NIST (National Institute of Standards and Technology—Time and Frequency Division)
WWVB radio station is located in Ft. Collins, Colorado, and transmits the exact time and date
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 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 information on the atomic
clock and WWVB please see the NIST website at
http://www.boulder.nist.gov/timefreq/stations/wwvb.htm.
The Radio Controlled WWVB Clock is normally controlled by the radio signal of the WWVB time
code transmitter and will thus set time and date automatically. Under bad reception conditions
however both can be set manually as follows:
Setting the Time
To set the time, touch the time display.
Next, touch the
٭
TIME
٭
field in the menu section (last two lines on the LCD).
Set the hours and minutes. Leave the mode with
٭
EXIT
٭
or wait for automatic time-out.
Setting the Date
To set the date, touch the date display.
Set the year, month and date of day. Leave the mode with
٭
NEXT
٭
.
Note:
By twice touching the DATE section the display will toggle between the following:
•
Date in MM.DD.YY format
•
Weekday (abbrev.), Date of Day, Month
•
Seconds
•
Set Alarm Time
Setting the Time Alarm
To set the Time Alarm, first touch the time field. Then touch the
٭
ALARM
٭
field in the menu
section (last two lines on the LCD).
Set hours and minutes for the time alarm. Exit time alarm mode with
٭
EXIT
٭
.
Note:
The time alarm is activated/deactivated by twice touching the TIME section. Here the alarm
symbol (((
•
))) will show or disappear after
٭
EXIT
٭
(or automatic time-out).
