Digital Compass Precautions - Casio 3071 Operation Manual

Operation Guide 3071 ( B )

Digital Compass Precautions

This watch features a built-in magnetic bearing sensor that detects terrestrial
magnetism. This means that north indicated by this watch is magnetic north,
which is somewhat different from true polar north. The magnetic north pole is
located in northern Canada, while the magnetic south pole is in southern
Australia. Note that the difference between magnetic north and true north as
measured with all magnetic compasses tends to be greater as one gets
closer to either of the magnetic poles. You should also remember that some
maps indicate true north (instead of magnetic north), and so you should make
allowances when using such maps with this watch.
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 direction readings are impossible while in a train, boat, air plane,
etc.
• Accurate readings are also impossible indoors, especially inside ferro-
concrete structures. This is because the metal framework of such structures
picks up magnetism from appliances, etc.
Storage
• The precision of the bearing sensor may deteriorate if the watch becomes
magnetized. Because of this, you should be sure to store the watch away
from magnets or any other sources of strong magnetism, including:
permanent magnets (magnetic necklaces, etc.) and household appliances
(TVs, personal computers, washing machines, freezers, etc.)
• Whenever you suspect that the watch may have become magnetized,
perform one of the calibration procedures under "Calibrating the Bearing
Sensor".
Calibrating the Bearing Sensor
You should calibrate the bearing sensor whenever you feel that the direction
readings being produced by the watch are off. There are three different
calibration methods available: magnetic declination correction, bidirectional
calibration, and northerly calibration.
• Magnetic Declination Correction
With magnetic declination correction, you 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.
Note that you can input the declination angle in degree units only, so you
may need to round off the value specified 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°.
• Bidirectional Calibration and Northerly Calibration
Bidirectional calibration and northerly calibration calibrate the accuracy of
the direction 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. With northerly calibration, you
"teach" the watch which way is north (which you have to determine with
another compass or some other means).
Important!
• If you want to perform both bidirectional and northerly calibration, be sure
to perform bidirectional calibration first, and then perform northerly
calibration. This is necessary because bidirectional calibration cancels any
existing northerly calibration setting.
• The more correctly you perform bidirectional calibration, the better the
accuracy of the bearing sensor readouts. You should perform bidirectional
calibration whenever you change environments where you use the bearing
sensor, and whenever you feel that the bearing sensor is producing
incorrect readings.
To perform magnetic declination correction
1. In the Digital Compass Mode, hold down E
Magnetic declination
for about two seconds until the magnetic
angle direction
declination angle value starts to flash. This is
the setting screen.
2. Use A (+) and C (–) to change the magnetic
declination angle value.
3. Press D to move the flashing to the magnetic
declination correction direction setting (OFF,
E, W).
• This will cause the magnetic declination
angle direction setting to flash.
Magnetic
declination
angle value
4. Use A to cycle the direction setting between the following options.
• OFF: No magnetic declination correction
• E: When magnetic north is to the east (east declination)
• W: When magnetic north is to the west (west declination)
• The illustration above, 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.
5. When the setting is the way you want, press E to exit the setting screen.
• Selecting OFF for the magnetic declination angle direction causes the
watch's magnetic declination angle value to change to
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.
• Make sure that you 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 field, for example, calibrate in an open
field.
To perform bidirectional calibration
1. In the Digital Compass Mode, hold down E
for about two seconds until the magnetic
declination angle value starts to flash. This is
the setting screen.
2. Press D twice to display the bidirectional
calibration screen.
• At this time, the north pointer flashes at the
12 o'clock position to indicate that the watch
is ready to calibrate the first direction.
3. Place the watch on a level surface facing any direction you want, and
press C to calibrate the first direction.
•
xxx is shown on the display while calibration is being performed.
When calibration of is successful, the display will show
and the north pointer flashes at the 6 o'clock position. This means that
the watch is ready for calibration of the second direction.
4. Rotate the watch 180 degrees.
5. Press C again to calibrate the second direction.
•
xxx is shown on the display while calibration is being performed. When
calibration is successful, the display will show
Mode (showing the angle value) screen.
• If
xxx appears and then changes to
screen, it means that there is something wrong with the sensor. When
ERR disappears after about one second, try performing the calibration
again. If ERR keeps appearing, contact your original dealer or nearest
authorized CASIO distributor to have the watch checked.
To perform northerly calibration
1. In the Digital Compass Mode, hold down E
for about two seconds until the magnetic
declination angle value starts to flash. This is
the setting screen.
2. Press D three times to display the northerly
calibration screen.
• At this time,
display.
3. Place the watch on a level surface, and position it so that its 12 o'clock
position points north (as measured with another compass).
4. Press C to start the calibration operation.
•
---
is shown on the display while calibration is being performed. When
calibration is successful, the display will show
°
Mode (with 0 shown as the angle value).
• If
--- appears and then changes to
screen, it means that there is something wrong with the sensor. When
ERR disappears after about one second, try performing the calibration
again. If ERR keeps appearing, contact your original dealer or nearest
authorized CASIO distributor to have the watch checked.
xx .
OK and ,
x2x
OK
and the Digital Compass
ERR
(error) on the calibration
-N- (north) appears on the
OK
and the Digital Compass
ERR (error) on the calibration
3