ashtech Reliance FS/2, Operation Manual

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64 Reliance with FS/2 Field Operations Manual
Q: Can I log more than one feature at a time?
A: Yes, provided the features are different types. A point can be logged
simultaneously with a line or area, a line can be logged simultaneously with an area,
and a point, line, and area can all be logged simultaneously.
Q: How do I log point features which are obstructed?
A: After selecting the point feature, use the Point Offset screen to enter a bearing and
distance or Easting and Northing from your current position to the point of interest.
Q: How do I set the receiver to run for a long period on a point?
A: Time on Points up to 60 minutes can be entered on the Data Logging Setup screen.
For longer periods, enter 0.00 minutes. Stop the manual logging by pressing F4
(DONE) on the point logging progress screen.
Q: How do I create and navigate to waypoints?
A: Individual waypoints can be created either on the PC in Map View, or on the FS/2
in the New Point screen by entering the coordinates. To navigate to a waypoint, select
the waypoint on the Point Selection screen of the FS/2, and then press F3 (NAVT) to
call the course to target and distance to target navigation information.
Q: How do I know if I’m computing a good position?
A: The Position screen on the FS/2 provides several indications of the accuracy of the
position being computed. Most importantly, the number of satellites must be four or
greater for accurate post-processing of the data.
The PDOP, which indicates the satellite constellation geometry, should be 6 or less.
The HRMS indicates the stand-alone accuracy of a single receiver. This accuracy is
greatly improved by post-processing. If real-time corrections are used (RTCM), the
HRMS indicates the accuracy of the corrected position.
Q: How far away from the base station can I be and still get accurate positions?
A: As the distance to the base station increases, the post-processed accuracy
decreases by 1 ppm of the baseline length. Thus, for the Decimeter receiver with a
100 km distance between the rover and the base station, accuracy decreases by 10 cm.
Distances beyond 100 km will also become increasingly less accurate due to
differences in the ionospheric distortion of the satellite signals received by the base
and rover receivers.
The base and rover must simultaneously track the same four (or more) satellites.