Product Manual

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Masks: These define limits that determine when a satellite will be
used or not used.
 Elevation: This is the minimum angle above the horizon that a
satellite must be located before it is used. A value of zero
would essentially turn off the elevation mask. A value of
ninety would mask all satellites. A typical elevation mask
setting is between five and fifteen degrees to block tracking of
those satellites potentially affected by multipath error due to
obstructions (e.g. buildings or trees). Multipath error is error to
the GPS position from the satellite signal bouncing off of
objects before reaching the GPS receiver.
 PDOP: This is the maximum allowable Position Dilution of
Precision (PDOP), which is a combination of HDOP, VDOP
and Time Dilution of Precision. While exceeded, the GPS data
will not be used for position calculations. This setting is
advantageous when quality and reliability of your position are
of concern. Typically, PDOP values of six or greater are
considered ―suspect‖ and therefore resulting positions are less
reliable.
 HDOP: This is the maximum allowable Horizontal Dilution of
Precision (PDOP), which is a measure of the geometrical
quality of the solution. While exceeded, the GPS data will not
be used for position calculations.
NOTE: DOPs can not be displayed in Binary Mode, however, the
DOP masks are still in effect.
GPS status voice prompt: When checked, changes in GPS quality
will result in an audible message indicating the change.
Advanced: When tapped, opens the Advanced GPS screen described
on the following page.