Spectra Precision Survey Pro v4.5 Ranger User Manual - Manual (Page 303)

GPS Module
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• You will be prompted to set a conventional survey scale
factor. Tap Update Scale to set the proper scale factor now.
• Select Use Scale Factor and tap Compute Scale to open the
Scale Calculator wizard. Select point b54 as the reference and
tap Calc. Scale>. Use the point’s height to calculate the
Ellipsoid Scale Factor
, and tap Solve>. Review the calculated
combined scale factor to be used for ground to grid reductions.
Also notice that the inverse combined factor is what you used
for our Ground Coordinates system scale factor
• Tap OK to close the Job > Settings screen.
16. Examine the inverse between points to see the effects of scale
factor.
• Examine the inverse between PiD101 and 101; they should
still be at the same location.
• Examine the inverse between bChap and 101, notice the
horizontal distance is now less than 1000
17. Take more measurements in grid coordinates.
• Switch to Conventional mode, and go to the Survey >
Traverse/Sideshot screen.
• Tap Backsight, and setup on point b54 and backsight point
bChap.
• Tap Side Shot to point 200, enter 90-00-00 and 1000 ft.
• Tap Side Shot to point 201, enter 135-00-00 and 1000 ft.
• Review the Results tab and notice the horizontal distance is
scaled by the combined factor.
• Examine the inverse between 201 and 101; these two points
are at the same location.
18. Do some COGO in the grid system.
• Go to COGO > Point in Direction
• Select your occupy point as the From Point.
• Set the backsight azimuth as the Azimuth. You can enter b54
– bchap.