Brunton GeoTransit, Operator'S Manual

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8. Read azimuth where the " N " end of the needle points at
graduated circle. (Fig 13)
3.3 Azimuth Measurement Waist-Level
This method is often used when object is above or below
the observer.
3.3.a Using "N" End of Needle
Use this method when the object lies as much as 45°
above, or 15° below the observer.
1. Hold transit waist high and in your left hand.
2. Open cover toward your body . (Fig 14)
3. Open large sight, until perpendicular to the body.
(Fig 14)
4. Press left forearm against
your waist and steady with
right hand.
5. Level compass using round
bubble level.
6. In the mirror’s reflection, bisect the object with the mirror center
line. (Fig 15)
•
Check that the bubble is centered in the round level.
7. Read azimuth where the " N " end of needle points at the graduated
circle.
If object is more than 45° above you, open mirror further toward your
body, and adjust large sight so that it leans over the bottom case.
3.3.b Using "S" End of Needle
Use this method when object is more than 15° below the observer.
1. Hold transit waist high and in your left hand.
2. Open cover away from your body. (Fig 16)
3. Open large sight until it leans over the body.
4. Press left forearm against your waist and steady with
right hand.
5. Look just over the large sight, and at the object
through window opening on mirror. (Fig 16)
•
Adjust mirror and large sight so that the image of
the large peep sight are bisected by the mirror
center line.
6. Level compass using round bubble level.
7. Read azimuth where the "
S " end of needle points at
the graduated circle. (Fig 17)
3.4 Using as a Prismatic Compass
Occasionally, objects may interfere with sighting using meth-
ods previously mentioned, or users may encounter circum-
stances which require the GEO be held at eye-level to sight
an object. If this is the case, follow the procedures below.
1. Open cover away from your body to approximately 45°, and open small sight. (Fig 18)
2. Lift large sight until perpendicular to the transit body, or leans slightly away from the base.
3. Hold instrument at eye-level, with large sight toward you.
4. Align large sight and small sight on top of the cover with
object.
• OR - Sight object through the lower portion of large sight
and the window in the mirror.
5. Level round bubble level using the reflection of the mirror.
6. Read azimuth in the reflection of the mirror where the "
S "
end of needle points at the graduated circle.
Figure 18
TO EYE
Figure 17
10 9
Figure 15
Figure 16
Figure 13
Figure 14
TO
EYE