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North Reference
‘Reference’ refers to the orientation of a map’s grid. Map makers try to align the vertical
lines on a map with True North. True North is the direction from any location on the
earth’s surface to the ‘north pole’. Maps are typically referenced to true north. Because a
compass points to magnetic north, not true north, maps indicate the difference between
true and magnetic north with a measurement called ‘declination’. The amount of declina-
tion changes as you move around the earth. Magnetic North is the direction in which a
compass needle points.
The Geko 101 bearings will correspond to the compass if the Geko 101 is set to
magnetic north. Due to errors introduced when map makers fl atten the earth’s sphere onto
paper, not all of the grid lines drawn on the map point exactly to the north pole, so the
north indicated by the grid lines is called ‘Grid North’. The difference, however, is usually
small enough that ‘Grid’ north can be considered the same as True North for travelling on
land. If necessary, manually correct for the difference between Grid North and True North.
To change the North Reference:
1. From the MENU Page press the UP or DOWN button to highlight ‘UNITS’ and then
press the OK button to display the UNITS page.
2. Press the UP or DOWN button to highlight the ‘NORTH REF’ fi eld and press the OK
button.
3. Press the UP or DOWN button to highlight your selection and then press the OK
button.
4. Press the PAGE button to return to the MENU page.
When you select the ‘DEFAULTS’ fi eld and press
the OK button
to return the UNITS
page to the factory settings.
Menu Page
‘MAGNETIC’ north is the
default north reference
setting.
Units Page
190-00297-00_0C.indd 18 10/1/2003, 12:59:15 PM