Congratulations upon your selection of this CASIO watch. To get the most out of your
purchase, be sure to read this manual carefully.
Keep the watch exposed to bright light
• The watch continues to operate, even when it is not exposed to light. Leaving the
watch in the dark can cause the battery to run down, which will result in some watch
functions to be disabled. If the battery goes dead, you will have to re-configure watch
settings after recharging. To ensure normal watch operation, be sure to keep it
exposed to light as much as possible.
Battery charges in the light.
(Converts light to
• Press C to change from mode to mode.
• In any mode (except when a setting screen is on the display), press B to illuminate
the display for about one second.
Radio-controlled Atomic Timekeeping
Month – Day
(Hour : Minutes
• When using the watch outside the areas covered by the time signal transmitters, you
will have to adjust the current time setting manually as required. See "Timekeeping"
for more information about manual time settings.
• The U.S. time calibration signal can be picked up by the watch while in North
America. The term "North America" in this manual refers to the area that consists of
Canada, the continental United States, and Mexico.
To specify your Home City
3. Press A to exit the setting screen.
Operation Guide 3107
The electricity generated by the solar cell of the watch is
stored by a built-in battery. Leaving or using the watch where
it is not exposed to light causes the battery to run down.
Make sure the watch is exposed to light as much as possible.
• When you are not wearing the watch on your wrist,
position the face so it is pointed at a source of bright light.
• You should try to keep the watch outside of your sleeve
as much as possible. Charging is reduced significantly if
the face is only partially covered.
Battery discharges in the dark.
This watch receives a time calibration signal and updates
its time setting accordingly.
• Supported time calibration signals: Germany
(Mainflingen), England (Anthorn), United States (Fort
Current Time Setting
This watch adjusts its time setting automatically in
accordance with a time calibration signal. You can also
perform a manual procedure to set the time and date,
• The first thing you should do after purchasing this watch
is to specify your Home City (the city where you
normally will use the watch). For more information, see
"To specify your Home City".
1. In the Timekeeping Mode, hold down A the city code
starts to flash. This is the setting screen.
2. Press D(east) and B(west) to select the city code you
want to use as your Home City.
• Time calibration signal reception is supported when
any one of the city codes shown in the table below is
selected as your Home City.
• The actual level at which some functions are disabled depends on the watch model.
• Frequent display illumination can run down the battery quickly and require charging.
The following guidelines give an idea of the charging time required to recover from a
single illumination operation.
Approximately 5 minutes exposure to bright sunlight coming in through a window
Approximately 50 minutes exposure to indoor fluorescent lighting
• Be sure to read "Power Supply" for important information you need to know
when exposing the watch to bright light.
If the display of the watch is blank...
If the display of the watch is blank, it means that the watch's Power Saving function
has turned off the display to conserve power.
• See "Power Saving Function" for more information.
Note that CASIO COMPUTER CO., LTD. assumes no responsibility for any damage
or loss suffered by you or any third party arising through the use of this product or
About This Manual
Some or all
• Normally, your watch should show the correct time as soon as you select your Home
City code. If it does not, it should adjust automatically after the next auto receive
operation (in the middle of the night). You can also perform manual receive or you
can set the time manually.
• The watch will receive the time calibration signal automatically from the applicable
transmitter (in the middle of the night) and update its settings accordingly. For
information about the relationship between city codes and transmitters, see "Home
City Codes and Transmitters".
• Under factory default settings, auto receive is turned off for all of the following city
codes: MOW (Moscow), HKG (Hong Kong), BJS (Beijing), HNL (Honolulu), and
ANC (Anchorage). For details about turning on auto receive for these city codes, see
"To turn auto receive on and off".
• You can disable time signal reception, if you want. See "To turn auto receive on and
off" for more information.
• See the maps under "Approximate Reception Ranges" for information about the
reception ranges of the watch.
• If you are in an area that does not use Daylight Saving Time (summertime), turn off
the DST setting.
Time Calibration Signal Reception
There are two different methods you can use to receive the time calibration signal:
auto receive and manual receive.
• Auto Receive
With auto receive, the watch receives the time calibration signal automatically up to
six times a day. When any auto receive is successful, the remaining auto receive
operations are not performed. For more information, see "About Auto Receive".
• Manual Receive
Manual receive lets you start a time calibration receive operation with the press of a
button. For more information, see "To perform manual receive".
• When getting ready to receive the time calibration signal, position the watch as
shown in the nearby illustration, with its 12 o'clock side facing towards a window.
This watch is designed to receive a time calibration signal late at night. Because of
this, you should place the watch near a window as shown in the illustration when you
take it off at night. Make sure there are no metal objects nearby.
• Make sure the watch is facing the right way.
• Depending on the model of your watch, display text
appears either as dark figures on a light background, or
light figures on a dark background. All sample displays
in this manual are shown using dark figures on a light
• Button operations are indicated using the letters shown
in the illustration.
• Each section of this manual provides you with the
information you need to perform operations in each
mode. Further details and technical information can be
found in the "Reference" section.
World Time Mode
Countdown Timer Mode