background image

MODEL: WT-941  

 

WWVB—RADIO CONTROLLED WATCH 

 

ABOUT WWVB (Radio Controlled Time) 

 
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 signal continuously at 60 kHz.  The signal can be received up to 2,000 
miles away through the internal antenna in the watch.  However, due to the nature of 
the Earth’s Ionosphere, reception is very limited during daylight hours.  The Watch 
will search for a signal every night when reception is best.  The WWVB radio station 
derives its signal from the NIST Atomic clock in Ft. Collins, 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.  This watch is regulated by the WWVB transmitter. 

 

 

SET-UP GUIDE, FEATURES, AND OPERATION 

I. 

II. 

III. 

IV. 

V. 

TIME ZONE SELECTION 
 

The default Time Zone is Eastern Time (EST, also GMT-5).  There are 25 
Time Zones to choose from.  The selection will cycle from GMT-5 to GMT-
12, then GMT+12 to GMT +1, then GMT, then GMT-1 to GMT –5. 

 

1. 

Hold down the 

TIME ZONE

 button for 2 seconds, or until a Time 

Zone abbreviation and “ZONE” flash in the LCD, and release.

 

2. 

Repeatedly press the 

TIME ZONE 

button until the appropriate Time 

Zone is displayed.

 

3. 

Wait 6 seconds for the automatic time-out to exit the Time Zone 
selection mode. 
 

 

 

 

 

 

 

 
 
 

ACTIVATION 
 

The Radio-Controlled watch is programmed and shipped in a battery-saving 
mode.  The LCD (Liquid Crystal Display) displays “OFF” and must be 
activated before set-up can begin. Your watch may not be in this mode; if not 
all you need to do is set your time zone (the correct time may or not be 
shown).

 

DAYLIGHT SAVING TIME (DST) 
 

Through the WWVB signals, the watch automatically adjusts for Daylight 
Saving Time. 
 

SHUTDOWN AND RESETTING  
 

This procedure will clear all information.  Follow the above sections (I, II) to 
activate the watch again. 

 

1. Press 

the 

TIME ZONE

 button briefly to activate the WWVB reception 

search.  The LCD lights up briefly and will then display “-:--” and the 
watch will begin to search for the WWVB signal. If a signal is found, 
a “tower” icon will flash; if no signal is present, no icon will flash. 
 
 
 
 

1. 

Hold down the 

TIME ZONE

 button for 6 seconds.  The LCD will 

cycle from normal display, to Time Zone display, and back to normal 
display.  The final display will be “OFF.”  

 

2. 

Within six minutes, the watch will either set to the exact time and 
date (Eastern is the default), or will display “-:--”. 

TIME ZONE key 

Atlantic Time (ATL): GMT-4 

Alaska Time (ALA): GMT-9 

Eastern Time (EST): GMT-5 

Hawaii Time (HAW): GMT-10 

Central Time (CST): GMT-6 

 

Mountain Time (MST): GMT-7   
Pacific Time (PST): GMT-8 

Greenwich Mean Time (GMT): GMT 

“Hawaii Time displayed  
(GMT-10) 

MANUALLY ACTIVATING THE WWVB SEARCH 
 

At any time after the Time Zone has been selected, and during the normal 
operating mode: 

 

 

Do not press the 

TIME ZONE

 button while the watch is searching for the 

WWVB signal, which normally takes 6-10 minutes.  However, the optimal 
time for WWVB reception is between midnight and 6:00 a.m., reception may 
not occur until this time period.  When the WWVB search is complete the 
time and date will automatically be displayed in the LCD.  If the watch is not 
within range of WWVB signals for an extended period of time it will still 
continue to operate as a highly accurate quartz controlled clock. 
 

1. 

Hold down the 

TIME ZONE

 button for 4 seconds (the LCD will 

display the time zone then will revert back to normal view).  The 
WWVB tower icon will appear in the upper right corner of the LCD, 
indicating that the watch is searching for a WWVB signal. 
 

Note:

 It is important not to hold the TIME ZONE button down long 

enough to shutdown or reset the watch.

  

 

Reviews: