Spectra Precision Survey Pro v5.1 - Manual (Page 32)

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3. If you choose New Point:
– Place a target at the unknown (new) backsight point.
– Aim the instrument at this point.
– Enter the known or an assumed value of azimuth along this direction.
– Enter the desired value of backsight circle for this direction (typically
“0” or true azimuth). If the Survey with True Azimuths setting is enabled,
then the circle value will automatically be set by Survey Pro.
– Tap Set Circle.
– Specify the type of target used at the backsight point ( Fixed Target or
Roving Target).
– Using , select the name of this target. As a result, the HR field is
updated to provide the height of this target. Update the height value if
necessary.
– Tap Measure Backsight.
– After making sure the instrument is sill pointed at the backsight point,
tap OK.
– Enter a name and description for the new backsight point.
– Tap to measure and store the point.
– Tap Finish. You can now start measuring new points.
Station Setup on Unknown Point, Resection Method
The resection method is illustrated below.
At least two known points should be observed to solve the station setup (e.g.
PT1, PT2). Other known points (PT3, PT4,..) may be added to refine the
computation.
PT1
PT3
PT2
PT4