Spectra Precision FAST Survey - Manual (Page 65)

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Known Base Position
Unknown Base Position
Using a
background Map
in FAST Survey
Click on the link below to read a tutorial on how to use an
image file as a background map:
http://update.carlsonsw.com/
kbase_main.php?action=display_topic&topic_id=477
Choice Case of Use
Previously Sur-
veyed Point
Choose this option if the base is installed on a point you sur-
veyed earlier and the latitude, longitude and ellipsoidal height
of this point are saved in the open job. In this case, select this
point from the job’s point list or select it graphically on the map
of the working area.
Use Local Coor-
dinates
Choose this option if the coordinates of the point where the
base is installed are known and expressed in the projection
system used in the job.
You can enter the local coordinates either manually or by
choosing a point from the job’s points list. In this case, and
unlike the previous choice, the point from the points list is
defined with local instead of geographical (lat, lon, height)
coordinates.
Read from File
Choose this option if the geographical coordinates of the base
were saved earlier to a REF file. Then select this file to load
the position held in this file as the base position.
Choice Case of Use
Read from GPS
Choose this option if you want the base receiver to determine
its own WGS84 coordinates.
The coordinates will be determined to within 1-3 meters as the
autonomous GPS or S-DGPS mode is used in this case. To
improve the accuracy of the computation, FAST Survey
prompts you to take several readings (typically 10 readings or
x readings over a certain period of time) so that all these read-
ings can be averaged to provide a more accurate position
solution for the base.
Enter Lat/Lon
Choose this option if you know and want to enter manually the
latitude, longitude and ellipsoidal height of the base location,
rather than ask the receiver to compute them by itself.
The coordinates should be entered in the “dd.mmssss” format
for latitude and longitude.
Enter Grid Sys-
tem Coordinates
Choose this option to freely enter base coordinates expressed
in the projection system used in the job. You may enter them
manually or derive them from a point in the points list or a
point you select on the map of the working area.