Operation Guide 2607 2637 2687
4
T o turn the auto light switch on and off
In any mode, hold down L for about tw o seconds to toggle the auto light switch on
(auto light switch on indicator displayed) or off (auto light s witch on indicator not
display ed).
• The auto light switch on indicator is on the display in all modes while the auto light
switch is turned on.
Battery
This watch is equipped with a solar cell and a rechargeab le battery (secondar y
battery) that is charged by the electrical power produced by the solar cell. The
illustration shown below sho ws how you should position the w atch for charging.
Example: Orient the watch so its face
is pointing at a light source.
• Note that charging efficiency drops
when any part of the solar cell is
block ed by clothing, etc.
• The illustration shows how to position
a watch with a resin band.
Important!
• Stor ing the watch for long periods in an area where there is no light or wearing it in
such a wa y that it is block ed from exposure to light can cause rechargeab le battery
power to run down. Be sure that the watch is normally exposed to bright light
whenever possib le.
Solar cell
• 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 v ery long use over a number of years, the rechargeab le
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 rechargeab le battery replaced.
• The rechargeable batter y should be replaced with a CASIO-specified CTL1616
battery only . Other rechargeable batteries can cause damage to the w atch.
• All data stored in memor y is deleted, and the current time and all other settings
return to their initial factory defaults whenev er battery power drops to Lev el 4 and
when you hav e the battery replaced.
• T urn on the watch’s P ower Saving function and k eep it in an area nor mally exposed
to bright light when storing it for long periods. This helps to keep the rechargeable
battery from going dead.
Battery Po wer Indicator
The battery power indicator on the display sho ws you the current status of the
rechargeable battery’ s po wer.
Battery power
indicator
Recover
indicator
Level
1
2
3
4
Battery Po wer 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 2607 2637 2687
• The Level 3 charge warning indicator tells you that battery power is v ery low , and
that exposure to bright light f or 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 Le vel 3
from Lev el 4. Y ou will not be able to configure any of the other settings until the
battery reaches Level 2 after dropping to Le vel 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 fe w minutes.
• If you use the backlight or the alarms a number of times during a shor t period, the
recover indicator (R
/RECO VER ) appears on the display and the f ollowing
operations become disabled until battery power reco vers.
Backlight
Beeper tone
Calibration reception
After some time, battery power will recov er and the recover indicator ( R /
RECO VER
) will disappear, indicating that the abo ve functions are enab led again.
Charging Precautions
Cer tain charging conditions can cause the watch to become v ery hot. Av oid leaving
the watch in the areas described below whene ver charging its rechargeable battery .
Also note that allowing the watch to become v ery hot can cause its liquid cr ystal
display to b lack out. The appearance of the LCD should become normal again when
the watch returns to a lower temper ature.
W arning!
Leaving the watch in bright light to c harge its rechargeable battery can cause it
to become quite hot. T ake care when handling the watch to avoid burn injury .
The watch can become particularly hot when exposed to the f ollowing
conditions for long periods.
• On the dashboard of a car par ked in direct sunlight
• T oo close to an incandescent lamp
• Under direct sunlight
Charging Guide
After a full charge, timekeeping remains enabled f or up to about six months, while the
watch is used under the conditions described below .
Operating Conditions
•
W atch is not exposed to light
•
Display on 18 hours per da y , sleep state 6 hours per day
•
1 backlight operation (1.5 seconds) per da y
•
10 seconds of alarm operation per day
•
4 times calibration reception per da y
Charge Times
Exposing the watch to light for the periods sho wn below each day restores the po wer
used by the abov e operating conditions.
• Stable operation is promoted by frequent charging.
Recovery Times
The table below sho ws the amount exposure that is required to tak e the battery from
one lev el to the next.
Exposure Level (Brightness) Appro ximate
Exposure Time
Outdoor Sunlight (50,000 lux) 5 minutes
Sunlight Through a Windo w (10,000 lux) 24 minutes
Daylight Through a Window on a Cloudy Da y (5,000 lux) 48 minutes
Indoor Fluorescent Lighting (500 lux) 8 hours
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)
Appro ximate Exposure Time
Lev el 4 Lev el 3 Lev el 2 Lev el 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 f or reference only . Actual required exposure
times depend on lighting conditions.
Reference
This section contains more detailed and technical information about watch oper ation.
It also contains important precautions and notes about the various features and
functions of this watch.
A uto Return Features
• If you leave the watch in the Time Recorder Mode or Alar m Mode for tw o or three
minutes without performing any oper ation, it automatically returns to the
Timekeeping Mode.
• If you leave a screen with flashing digits on the displa y for two or three min utes
without performing any operation, the w atch automatically saves anything y ou hav e
input up to that point and exits the setting screen.
Data and Setting Scrolling
The B and D buttons are used in v arious modes and setting screens to scroll
through data on the display . In most cases , holding down these buttons during a scroll
operation scrolls through the data at high speed.
Initial Screens
When you enter the Alarm or W orld Time Mode, the data you w ere viewing when you
last exited the mode appears first.
Time Calibration Signal Reception Precautions
• Reception is best when the antenna built into the 12 o'clock edge of the watch is
facing in the gener al direction of the signal transmitter . Note, howe ver, that mo ving
the watch while the time calibration signal receiv e operation is taking place will make
stable reception impossible .
• Proper signal reception can be difficult or even impossible under the conditions listed
below .
• Radio interference can make signal reception impossible.
• Strong electrostatic charge can result in the wrong time being set.
• Even when the watch is within the reception range of the transmitter , signal
reception is impossible if the signal is bloc ked by mountains or other geological
formations between the watch and signal source.
Inside or
among
buildings
Inside a
vehicle
Near
household
appliances or
office
equipment
Near a
construction
site, airpor t, or
other sources
of electrical
noise
Near high-
tension
power lines
Among or
behind
mountains
• Signal reception is affected by weather , atmospher ic conditions, and seasonal
changes.
• The time calibration signal is bounced off the ionosphere. Because of this, such
factors as changes in the reflectivity of the ionosphere, as w ell as mov ement of the
ionosphere to higher altitudes due to seasonal atmospheric changes or the time of
day ma y change the reception range of the signal and make reception temporarily
impossible.
• The watch is designed to automatically update the date and day of the week for the
period January 1, 2000 to December 31, 2099. Setting of the date b y the time
calibration signal cannot be performed starting from January 1, 2100.
• This watch can receive signals that differentiate between leap y ears and non-leap
years.
• If you are in an area where proper time calibration signal reception is impossible, the
watch keeps time within ±15 seconds a month at normal temperature.