User's Manual

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After your unit has downloaded the current satellite information,
Assisted GPS (A-GPS) will retain a memory of the satellite paths
up to 72 hours. Therefore the GPS can lock on the satellites
quickly, in less than 20 seconds in an open sky.
SatViewer provides a way to quickly start using the GPS
functionality of the unit, but it is not a stand-alone mapping, GIS or
navigation program by itself. SatViewer is useful for checking the
GPS configuration and enabling advanced features of your unit GPS
receiver when these settings are not made available in other
applications. When changing any GPS settings or other settings, it is
important to wait a few moments after tapping on the desired option
to allow time for your GPS receiver to implement the requested
change. SatViewer communicates with the GPS receiver on your
unit to compute your current position, speed, direction (azimuth)
and height. This information is displayed at the top of the screen
along with other information about the satellite signals. Speed and
direction measurements are only useful when the GPS receiver is in
motion. Standing in one position with the GPS receiver may result
in inaccurate readings in direction and speed. If you are not moving,
direction is reported as ? and speed is reported as “0”. Height
calculations from a GPS receiver are typically not very accurate.
Vertical accuracy is about two to three times worse than the
horizontal accuracy). Units of measurement are only displayed in
U.S. feet and heights are only displayed in height above mean sea
level (MSL).
The pages of the application are accessed by tapping the various
tabs, which are laid out in index card format. The information in
each tab is described on the following pages.