Congratulations upon your selection of this CASIO watch. To get the most out of your
purchase, be sure to read this manual carefully.
• This watch does not have a city code that corresponds to the UTC offset of –3.5
hours. Because of this, the radio-controlled atomic timekeeping function will not
display the correct time for Newfoundland, Canada.
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 B to change from mode to mode.
• In any mode, press A to illuminate the face of the watch.
• Holding down B for at least two seconds at any time will return directly to the
Switching the Display Screen
Each press of C changes the contents of the digital display.
Day of week
Radio-controlled Atomic Timekeeping
This watch receives a time calibration signal and updates its time setting accordingly.
• This watch is designed to pick up the time calibration signals transmitted in Germany
(Mainflingen), England (Anthorn), the United States (Fort Collins), China (Shangqiu),
and Japan (Fukushima, Fukuoka/Saga).
Current Time Setting
This watch adjusts its time setting automatically in accordance with a time calibration
signal. You also can perform a manual procedure to set the time and date, when
• 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".
• 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.
• As of March 2010, China does not use Daylight Saving Time (DST). If China does go
to the Daylight Saving Time system in the future, some functions of this watch may
no longer operate correctly.
• Using this watch in a country covered by a time calibration that is different from the
countries it supports may result in incorrect time indication due to local application of
summer time, etc.
Operation Guide 5135
The electricity generated by the solar cell of the watch is
stored by a rechargeable 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
• You should try to keep the watch outside of your sleeve
as much as possible. Charging is reduced significantly if
the face is covered only partially.
Battery discharges in the dark.
Appears when reception
Hour : Minutes
• 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 about 8 hours 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
• 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 background.
• 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.
Some or all
World Time Mode
Countdown Timer Mode
To specify your Home City
1. In the Timekeeping Mode, hold down A for about three
seconds. You can release the button after "ADJ"
appears on the display.
• At this time, "12H" (12-hour timekeeping) or "24H" (24-
hour timekeeping) also will be flashing on the display.
2. Press B.
• The city code of the current Home City will flash,
which indicates the setting screen.
3. Press C (east) to select the city code you want to use
as your Home City.
LON : London
PAR : Paris
ATH : Athens
HKG : Hong Kong
TYO : Tokyo
HNL : Honolulu
ANC : Anchorage
LAX : Los Angeles
DEN : Denver
CHI : Chicago
NYC : New York