Sokkia B20, Operator'S Manual, Page: 44 / 60

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6.2 MEASURING HORIZONTAL ANGLE
The horizontal circle graduations are annotated every 10 °
(360
°
) or 10 gon (400 gon) in a clockwise direction. As a
result, sighting is performed from left to right.
1) Use the plumb bob to set up the instrument directly
above the surveying point. (Fig.6.3)
Fig.6.3
2) Sight point A, and set the horizontal circle to 0
°
by
turning the horizontal circle positioning ring . (Fig.6.4)
Fig.6.4
3) Sight point B and take the angle reading.
Example: 91.5
°
(or 91.5 gon) in (Fig.6.5) below.
Fig.6.5
15
12
11