To Specify The Illumination Duration; Questions And Answers - Casio 2825 Operation Manual

Moving the watch to a position that is parallel to the ground and then tilting
it towards you more than 40 degrees causes the backlight to turn on.
• Wear the watch on the outside of your wrist.
Parallel to
ground
Warning!
• Always make sure you are in a safe place whenever you are reading
the display of the watch using the auto light switch. Be especially
careful when running or engaged in any other activity that can result
in accident or injury. Also take care that sudden illumination by the
auto light switch does not surprise or distract others around you.
• When you are wearing the watch, make sure that its auto light switch
is turned off before riding on a bicycle or operating a motorcycle or
any other motor vehicle. Sudden and unintended operation of the auto
light switch can create a distraction, which can result in a traffic
accident and serious personal injury.
To turn the auto light switch on and off
In any mode except while a setting is flashing on the display, hold down L for
about two seconds to toggle the auto light switch on (
not displayed).
• The auto light switch on indicator (
the auto light switch is turned on.
• The auto light switch turns off automatically whenever battery power drops
to Level 3.
• The backlight may not light right away if you raise the watch to your face
while a barometric pressure operation is in progress.
• The auto light switch is always disabled, regardless of its on/off setting,
when any one of the following conditions exists.
While a direction measurement operation is being performed in the
Digital Compass Mode or Depth Gauge Mode
While a bearing sensor calibration operation is being performed in the
Digital Compass Mode

To specify the illumination duration

1. In the Timekeeping Mode, hold down A until
the seconds start to flash, which indicates the
setting screen.
2. Press B to toggle the illumination duration
setting between 2.5 seconds ( ) and 1.5
seconds (
3. After the setting is the way you want, press A
to exit the setting screen.
Questions & Answers
Question: What causes incorrect direction readings?
Answer:
• Incorrect bidirectional calibration. Perform bidirectional calibration.
• Nearby source of strong magnetism, such as a household appliance, a
large steel bridge, a steel beam, overhead wires, etc., or an attempt to
perform direction measurement on a train, boat, etc. Move away from large
metal objects and try again. Note that digital compass operation cannot be
performed inside a train, boat, etc.
Question: What causes different direction readings to produce different
results at the same location ?
Answer: Magnetism generated by nearby high-tension wires is interfering
with detection of terrestrial magnetism. Move away from the high-
tension wires and try again.
Question: Why am I having problems taking direction readings indoors ?
Answer: A TV, personal computer, speakers, or some other object is
interfering with terrestrial magnetism readings. Move away from
the object causing the interference or take the direction reading
outdoors. Indoor direction readings are particularly difficult inside
ferro-concrete structures. Remember that you will not be able to
take direction readings inside of trains, airplanes, etc.
Question: What do the numbers on the watch mean ?
Answer: The face of this watch is marked with values that
increase in a counter- clockwise direction.
These values represent degrees. When you take a
direction reading, you can use these values to find
out how many degrees the 12 o'clock position of
this watch (which is the direction indicated in the
display) differs from magnetic north.
For example, when the Magnetic North Pointer is
Pointing at 90 on the watch's face, it means that
the 12 o'clock position is 90 degrees from
magnetic north (which means that the 12 o'clock
pointing due east).
Operation Guide 2825
More than
40 °
displayed) or off (
) is on the display in all modes while
).
Question: How does the barometer work?
Answer: Barometric pressure indicates changes in the atmosphere, and by
monitoring these changes you can predict the weather with
reasonable accuracy. Rising atmospheric pressure indicates good
weather, while falling pressure indicates deteriorating weather
conditions.
The barometric pressures that you see in the newspaper and on
the TV weather report are measurements corrected to values
measured at 0 m sea level.
Question: How does the watch calculate depth values?
Answer: Water pressure increases with depth. In the case of sea water
(specific gravity=1.025), water pressure increases by 1 ATM
(1.03 kg/cm 2 ) with each 10 meters (33 feet) of depth.
The pressure sensor of this watch measures water pressure, and
then converts it to an underwater depth reading, based on the
relationship between pressure and depth.
Question: Is there anything I need to keep in mind when diving at high
altitudes or in fresh water?
Answer: The depth reading is automatically reset to "0.0 m (0 ft)" whenever
the Depth Gauge Mode is entered, so you can use this watch for
skin diving at altitudes. Note, however, that malfunctions occur
when skin diving at altitudes greater than approximately 4,000
meters (13,000 ft.). In addition, as this watch bases its
calculations on sea water, which has a specific gravity of 1.025,
readings will be incorrect during fresh-water skin diving. During
fresh-water dives, you must assume that you are approximately
2.5% deeper than the depth shown on the display.
Example: When displayed depth is 5 meters, actual depth is
5 × 1.025 = 5.1 meters.
Battery
This watch is equipped with a solar cell and a rechargeable battery
(secondary battery) that is charged by the electrical power produced by the
solar cell. The illustration shown below shows how you should position the
watch for charging.
Example: Orient the watch so its face is
pointing at a light source.
• The illustration shows how to position a
watch with a resin band.
• Note that charging efficiency drops when
any part of the solar cell is blocked by
clothing, etc.
• Normally, you should try to keep the
watch outside of your sleeve as much as
possible. Charging is significantly reduced
if the face is only partially covered.
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.
• 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. If you experience problems 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 and Recover Indicator
The battery power indicator on the display shows you the current status of the
rechargeable battery's power.
Level Battery Power
Indicator
1
2
3
Battery power
indicator
(Charge Soon Alert)
4
• The flashing CHARGE indicator at Level 3 tells you that battery power is
very low, and that exposure to bright light for charging is required as soon
as possible.
Solar cell
Function Status
All functions enabled.
All functions enabled.
Except for timekeeping and
battery power indicator, all
functions and display indicators
are disabled.
All functions disabled.
6