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Operation Guide 2608 2638 2688
4
Important!
• Storing the watch for long periods in an area where there is no light or wearing it in
such a way that it is blocked from exposure to light can cause rechargeable battery
power to run down. Be sure that the watch is normally exposed to bright light
whenever possible.
• This watch employs a solar cell that converts light into electricity that charges a built-
in rechargeable battery. Normally, the rechargeable battery should not need
replacement, but after very long use over a number of years, the rechargeable
battery may lose its ability to achieve a full charge. Should you notice problems with
getting the rechargeable battery to a full charge, contact your dealer or CASIO
distributor about having the rechargeable battery replaced.
• The rechargeable battery should be replaced with a CASIO-specified CTL1616
battery only. Other rechargeable batteries can cause damage to the watch.
• All data stored in memory is deleted, and the current time and all other settings
return to their initial factory defaults whenever battery power drops to Level 4 and
when you have the battery replaced.
• Turn on the watch’s Power Saving function and keep it in an area normally exposed
to bright light when storing it for long periods. This helps to keep the rechargeable
battery from going dead.
Battery Power Indicator
The battery power indicator on the display shows you the current status of the
rechargeable battery’s power.
Battery power
indicator
Recover
indicator
Level
1
2
3
4
Battery Power Indicator
Charge Soon Alert
Function Status
All functions enabled.
All functions enabled.
Beeper tone, backlight,
calibration signal
reception, display, and
buttons are disabled.
All functions, including
timekeeping, are
disabled.
Module 2608 2638 2688
• The Level 3 charge warning indicator tells you that battery power is very low, and
that exposure to bright light for charging is required as soon as possible.
• At Level 4, all functions are disabled and settings return to their initial factory
defaults. Functions are enabled once again after the rechargeable battery is
charged, but you need to set the time and date after the battery reaches Level 3
from Level 4. You will not be able to configure any of the other settings until the
battery reaches Level 2 after dropping to Level 4.
• Leaving the watch in direct sunlight or some other very strong light source can
cause the battery power indicator to temporarily show a reading that is actually
higher than the battery level. The correct battery power indicator should appear after
a few minutes.
• If you use the backlight or the alarms a number of times during a short period, the
recover indicator (R
/RECOVER ) appears on the display and the following
operations become disabled until battery power recovers.
Backlight
Beeper tone
Calibration reception
After some time, battery power will recover and the recover indicator (R /
RECOVER
) will disappear, indicating that the above functions are enabled again.
Charging Precautions
Certain charging conditions can cause the watch to become very hot. Avoid leaving
the watch in the areas described below whenever charging its rechargeable battery.
Also note that allowing the watch to become very hot can cause its liquid crystal
display to black out. The appearance of the LCD should become normal again when
the watch returns to a lower temperature.
Warning!
Leaving the watch in bright light to charge its rechargeable battery can cause it
to become quite hot. Take care when handling the watch to avoid burn injury.
The watch can become particularly hot when exposed to the following
conditions for long periods.
• On the dashboard of a car parked in direct sunlight
• Too close to an incandescent lamp
• Under direct sunlight
Charging Guide
After a full charge, timekeeping remains enabled for up to about six months, while the
watch is used under the conditions described below.
Operating Conditions
•
Watch is not exposed to light
•
Display on 18 hours per day, sleep state 6 hours per day
•
1 backlight operation (1.5 seconds) per day
•
10 seconds of alarm operation per day
•
4 times calibration reception per day
Charge Times
Exposing the watch to light for the periods shown below each day restores the power
used by the above operating conditions.
Exposure Level (Brightness) Approximate
Exposure Time
Outdoor Sunlight (50,000 lux) 5 minutes
Sunlight Through a Window (10,000 lux) 24 minutes
Daylight Through a Window on a Cloudy Day (5,000 lux) 48 minutes
Indoor Fluorescent Lighting (500 lux) 8 hours
• Stable operation is promoted by frequent charging.
Recovery Times
The table below shows the amount exposure that is required to take the battery from
one level to the next.
Exposure Level
(Brightness)
Outdoor Sunlight
(50,000 lux)
Sunlight Through a
Window (10,000 lux)
Daylight Through a
Window on a Cloudy
Day (5,000 lux)
Indoor Fluorescent
Lighting (500 lux)
Approximate Exposure Time
Level 4 Level 3 Level 2 Level 1
1 hour 14 hours 3 hours
3 hours 70 hours 14 hours
5 hours 143 hours 28 hours
57 hours ------------ ------------
▲
▲
▲
• The above exposure time values are all for reference only. Actual required exposure
times depend on lighting conditions.
Timekeeping
Use the Timekeeping Mode to set and view the current time and date. This section
also explains how to manually set the current date and time.
• The watch is equipped with a Time Recorder feature that lets you record the current
Home City time (month, day, hour, minutes, seconds, and DST on/off setting) with
the touch of a button. See “To record a Time Recorder time” for more information.
• All of the operations in this section are performed in the Timekeeping Mode, which
you can enter by pressing C.
Setting the Time and Date Manually
Make sure you select your Home City code before you change the current time and
date settings. World Time Mode times are all displayed in accordance with the
Timekeeping Mode settings. Because of this, World Time Mode times will not be
correct if you do not select the proper Home City code before setting the time and
date in the Timekeeping Mode.
To set the current time and date manually
1.In the Timekeeping Mode, hold down A until the city
code starts to flash, which indicates the setting screen.
2.Press A or C to move the flashing in the sequence
shown below to select other settings.
Last Signal Screen
▲
Press D.
Day of week
Receive time
Month – Day
Hour : Minutes Seconds
PM
indicator
▲
Receive date
City/Auto receive
Settings
Time/Date/Power
Saving Settings
Auto
Receive
DSTCity Code
Seconds
Hour
Minutes
12/24-Hour
Format
Day
Month Year
Power Saving
on/off
/ Press A.
Press C.
C
A
C
City code
3. When the setting you want to change is flashing, use B and/or D to change it as
described below.
Screen: To do this:
Change the city code
Cycle between Daylight Saving Time
(
ON), Standard Time (OFF), and
Auto DST (AUTO)
Toggle between auto receive on
(
ON) and off (OFF)
Do this:
Use D (east) and B (west).
Press D.
Press D.
City/Auto Receive Settings
• See “City Code Table” for a complete list of available city codes.
Screen: To do this:
Toggle between 12-hour (12H) and
24-hour (24H) timekeeping
Reset the seconds to 00
Change the hour or minutes
Change the month, day, or year
Toggle the Power Saving on (ON)
and off (OFF)
Do this:
Press D.
Press D.
Use D (+) and B (–).
Use D (+) and B (–).
Press D.
Time/Date/Power Saving Settings
4. Use A to exit the setting screen.
• If a City/Auto Receive Setting screen is displayed, press A twice.
• If a Time/Date/Power Saving Setting screen is displayed, press A once.
Note
• Auto DST (
AUTO) can be selected only while HNL, ANC, LAX, DEN, CHI, or
NYC is selected as the Home City code. For more information, see “Daylight Saving
Time (DST)” below.
• The auto receive setting is used for time calibration signal reception only. See
“About Auto Receive” for details.