G-Shock GWN1000-9A - Manual (Page 8)

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• The direction indicated by the Digital Compass is magnetic north.
You can use Magnetic Declination Correction to confi gure the watch to indicate true north, if you want.
For details, see “Magnetic Declination Correction” below, “To perform magnetic declination correction”
(page E-58), and “Magnetic North and True North” (page E-60).
Calibrating the Bearing Sensor
You should calibrate the bearing sensor whenever you feel that the direction readings being produced by
the watch are off. You can use any one of two different bearing sensor calibration methods: bidirectional
calibration or magnetic declination correction.
• Bidirectional Calibration
Bidirectional calibration calibrates the bearing sensor in relation to magnetic north. Use bidirectional
calibration when you want to take readings within an area exposed to magnetic force. This type of
calibration should be used if the watch becomes magnetized for any reason.
Important!
• To ensure correct direction readings by this watch, be sure to perform bidirectional calibration before
using it. The watch may produce incorrect direction readings if you do not perform bidirectional
calibration.
• Magnetic Declination Correction
With magnetic declination correction, you select a declination angle direction and input a magnetic
declination angle (difference between magnetic north and true north), which allows the watch to indicate
true north. You can perform this procedure when the magnetic declination angle is indicated on the map
you are using.
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Precautions about bidirectional calibration
• You can use any two opposing directions for bidirectional calibration. You must, however, make sure
that they are 180 degrees opposite each other. Remember that if you perform the procedure
incorrectly, you will get wrong bearing sensor readings.
• Do not move the watch while calibration of either direction is in progress.
• You should perform bidirectional calibration in an environment that is the same as that where you plan
to be taking direction readings. If you plan to take direction readings in an open fi eld, for example,
calibrate in an open fi eld.
To perform bidirectional calibration
1. In the Digital Compass Mode, pull out the crown.
• This will cause 1 to appear on the digital display, with up arrow ( )
fl ashing.
• The timekeeping (hour, minute, second) hands will move to
2 o’clock.
2. While keeping the watch horizontal, press A.
• WAIT will be shown on the digital display while calibration is
in progress. OK, Turn180° will appear on the digital display if
calibration is successful, and then 2 will appear.
• If ERR appears on the display, press A again to restart the
direction reading operation.
3. Rotate the watch 180 degrees.
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4. Press A again to calibrate the second direction.
• WAIT is shown on the display while calibration is being performed.
When calibration is successful, the display will show OK and then change to the Digital Compass
Mode screen.
If ERR appears on the display, go back to step 1 of this procedure.
5. After calibration is complete, push the crown back in.
To perform magnetic declination correction
1. In the Digital Compass Mode, pull out the crown.
• This will cause 1 to appear on the digital display, with up arrow ( )
fl ashing.
• The timekeeping (hour, minute, second) hands will move to
2 o’clock.
2. Press B.
• This will cause DEC and the current magnetic declination setting
to appear on the digital display.
Magnetic declination angle
direction value (E, W)
Magnetic declination
angle value
Magnetic declination angle
direction value (E, W)
Magnetic declination
angle value
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3. Rotate the crown to change the magnetic declination direction and angle setting as required.
North Setting Setting
Magnetic North 0°
True North
E 90° to W 90°
E: East declination (Magnetic north is east of true north.)
W: West declination (Magnetic north is west of true north.)
• Note that you can input the declination angle in whole degree units only, so you may need to round
off the value specifi ed on the map. If your map indicates the declination angle as 7.4°, you should
input 7°. In the case of 7.6° input 8°, for 7.5° you can input 7° or 8°.
• You can also use HS1 high-speed movement (page E-6) to change this setting.
• You can return the setting to 0° by press A and C at the same time.
• The illustration, for example, shows the value you should input and the direction setting you should
select when the map shows a magnetic declination of 1° west.
4. After calibration is complete, push the crown back in.
Setting a map and fi nding your current location
Having an idea of your current location is important when mountain climbing or hiking. To do this, you
need to “set the map”, which means to align the map so the directions indicated on it are aligned with the
actual directions of your location. Basically what you are doing is aligning north on the map with north as
indicated by the watch.
• Note that map reading skills and experience are required to determine your current location and
destination on a map.
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Digital Compass Precautions
Magnetic North and True North
The northerly direction can be expressed either as magnetic north or true
north, which are different from each other. Also, it is important to keep in mind
that magnetic north moves over time.
• Magnetic north is the north that is indicated by the needle of a compass.
• True north, which is the location of the North Pole of the Earth’s axis, is the
north that is normally indicated on maps.
• The difference between magnetic north and true north is called the
“declination”. The closer you get to the North Pole, the greater the
declination angle.
Location
• Taking a direction reading when you are near a source of strong magnetism can cause large errors in
readings. Because of this, you should avoid taking direction readings while in the vicinity of the
following types of objects: permanent magnets (magnetic necklaces, etc.), concentrations of metal
(metal doors, lockers, etc.), high tension wires, aerial wires, household appliances (TVs, personal
computers, washing machines, freezers, etc.).
• Accurate readings are also impossible indoors, especially inside ferroconcrete structures. This is
because the metal framework of such structures picks up magnetism from appliances, etc.
• Accurate direction readings are impossible while in a train, boat, air plane, etc.
True north
Earth
Magnetic north
True north
Earth
Magnetic north
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Storage
• The precision of the bearing sensor may deteriorate if the watch becomes magnetized. Because of
this, you should store the watch away from magnets or any other sources of strong magnetism,
including: permanent magnets (magnetic necklaces, etc.), concentrations of metal (metal doors,
lockers, etc.), and household appliances (TVs, personal computers, washing machines, freezers, etc.).
• Whenever you suspect that the watch may have become magnetized, perform the procedure under “To
perform bidirectional calibration” (page E-57).
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Using the Altimeter Mode
The watch takes altitude readings and displays results based on air pressure measurements taken by a
built-in pressure sensor.
• The displayed altitude reading is a relative altitude that is calculated based on measurement of
changes in barometric pressure by the watch’s pressure sensor. This means that barometric pressure
changes can cause readings taken at different times at the same location to be different. Also note that
the value displayed by the watch may be different from the actual elevation and/or sea level elevation
indicated for the area where you are located.
• When using the altimeter of this watch for mountain climbing or other activities, it is highly
recommended that you check a map, local altitude indications, or some other source for your current
correct altitude and regularly calibrate the altimeter with the latest information.
Important!
• See “To specify a reference altitude value” (page E-66) and “Altimeter Precautions” (page E-72) for
information about how to minimize differences between readings produced by the watch and values
provided by local altitude (elevation) indications.
Getting Ready
Before actually taking an altitude reading you need to select an altitude reading interval.
Selecting the Altimeter Measurement Time and Interval
You can either of the two settings described below.
0'05": Readings for about one hour: every second for the fi rst three minutes, and then every fi ve
seconds for the remainder of the hour
2'00": Readings for about 12 hours; every second for the fi rst three minutes, and then every two
minutes for the remainder of the 12 hours
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To specify the altitude reading interval
1. In the Timekeeping Mode or any sensor mode, press A a number of
times until ALTI (Altimeter Mode) appears on the digital display.
• In a non-sensor mode, hold down B for about two seconds to
enter the Timekeeping Mode. Next, perform the above step.
2. Pull out the crown.
• This will cause the current altitude reading value to appear.
• The timekeeping (hour, minute, second) hands will move to 2
o’clock.
3. Press B.
• This will cause INT to appear on the digital display, along with the
fl ashing current reading interval setting.
4. Rotate the crown to select either fi ve second (0'05) or two minutes
(2'00) as the interval setting.
5. After the setting is the way you want, push the crown back in to exit the
setting screen.
Taking Altitude Readings
Use the procedure below to take basic altitude readings.
• See “Using Reference Altitude Values” (page E-65) for information about how to make altimeter
readings more accurate.
• See “How does the altimeter work?” (page E-71) for information about how the watch measures altitude.
Operation Guide 5371