Spectra Precision Survey Pro v4.6 Ranger User Manual - Manual (Page 145)

Other Conventional Surveying Tutorials
135
Horizontal Angle Offset Screen
The Horizontal Angle Offset screen is used to store a new point that
lies on a line tangent to the rod and perpendicular to the line formed
between the total station and the rod. (See illustration.) The routine
requires two shots by the total station; one at the prism, located to
the side of the new point; and one in the direction of the new point.
This example explains how to store a point at the center of an
obstacle – such as a big tree.
1. From the Main Menu, tap . Survey , Horz Angle Offset . If you
have not already setup your backsight, you will need to do so
before the Horizontal Angle Offset Shot screen will open.
2. The rod person should position the prism to
the side of the location of the new point so
that the angle formed by the new point, the
prism, and total station form 90°. (See
illustration.)
3. With the total station aimed toward the
new point, tap the Aim Center button.
Only the horizontal angle is measure
during this shot so a prism does not need to
be used.
4. Aim the total station toward the prism
located at the side of the new point and tap Shoot Prism . The
new point will be stored as a side shot.
Note: The center shot and the prism shot can be taken in either
order.