JDC Electronic SA Geos 11 - Manual (Page 25)

Magnetic Field in µTesla + Compass
Heading
Display
This mode is displayed as follows:
upper block: wind speed
large block : heading in degrees
middle block: indicates
, = degree (unit of the large
block) and = micro Tesla (unit of the lower block)
lower block: magnetic field in µTesla
Operation
The role of this mode is twofold:
1. allow a larger display of the heading in degrees
2. know the value of the magnetic field drift in µTesla in relation to the
calibration. This will give you an indication as to whether an external
element (steady magnetic field) is interfering with your compass; 0 µTesla
will indicate that no magnetic field is interfering with your compass and
that your instrument therefore offers you the highest level of accuracy.
To measure the value of an external magnetic field (a magnet for instance),
display 0 µT on the screen and bring the magnet close to the instrument:
the display shows the magnetic field output expressed in µT.
Calibration
Calibration is carried out as with the compass (please refer to relevant
section). If you already have calibrated the compass basic mode in the
standard screen, there is no need to do it again, unless you have just entered
a different environment. Please note that if you carry out a calibration in
this special mode, it will also be valid for the compass basic mode.
Magnetic declination
If you want the compass to indicate true North instead of the magnetic
North, enter the declination (in degrees) of the location where you are at.
To adjust this declination, access the special menu and then
display the Magnetic Field screen. While the
or
indication is flashing, keep the button pressed down,
starts flashing on the upper block. Once in the calibration
function (see opposite) release the button. Use the
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