Brunton ECLIPSE 8099, Инструкция по эксплуатации

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5. Sight a field bearing to
landmark ‘1’ – 320° ( green
scale), this example.
· See Section 4.1, Forward
Mirror Sighting, for help.
6. With both covers open to
180°, place clear base of
compass next to landmark
‘1’, on the map.
7. With green scale set to
320°, pivot compass around
landmark ‘1’ until
blue
orienting circle outlines red
circled "N" (figure 23).
8. Draw the 320° map bearing
line using the side of the
base, passing through
landmark ‘1’.
· Your position is some
where along this line
(figure 23).
9. Repeat process for
landmarks ‘2’ (50°) and
‘3’ (90°).
Either a point or a small
triangle will form at the
intersection of the three
lines. Your position is at
the point, or within the
small triangle (figure 24).
9. Keeping the clear base stationary on the map,
rotate azimuth ring until blue orienting circle
points in a northerly direction, and the red lines
on graduated circle are aligned with the drawn
true north-south lines (figure 21).
10.Read bearing from the green scale in magnified
index lens (figure 21).
If using a map other than a USGS or BLM map,
check that the map’s margin is aligned to true
north. If not aligned, it is necessary to draw true
north-south lines from the true north indicator
(indicated by an arrow with an "N" or a star).
Then, find map bearing.
8 -- Triangulation
In this section, you will determine field bearings to
three visible landmarks and plot them as map bearings.
The intersection of the bearing lines indicate your approximate position. A landmark can be a
mountain peak, a cliff, or any visible object displayed on your map. The following example uses a
USGS topo-map, and forward mirror sighting for bearing determination.
1. Adjust for magnetic declination.
2. Find three prominent landmarks in the field.
3. Orient the map to true north.
· See Section 7.1, Map Alignment, for help.
4. Find all three landmarks on the map, place an ‘X’ at the positions and label them ‘1’, ‘2’ & ‘3’
(figure 22).
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Figure 21
Figure 22
Figure 23
Figure 24
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