Garmin NavTalk Pilot - Manual (Page 88)

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Section 6
GPS Receiver
Reference
Introduction
3D Navigation - at least four satellites with good
geometry have been locked onto, and your position
is now being calculated in latitude, longitude and
altitude. ‘3D Diff’ will appear when you are
receiving DGPS corrections in 3D mode.
Poor GPS Coverage - the receiver isn’t tracking
enough satellites for a 2D or 3D fix due to bad
satellite geometry.
Not Usable - the receiver is unusable, possibly due
to incorrect initialization or abnormal satellite
conditions. Turn the unit off and back on to reset,
and re-initialize the receiver if necessary.
Simulating Nav - the receiver is in simulator mode.
The status bar displays ‘Sim’ on all main pages.
‘Need to Select Initialization’ Prompt
If no satellites are received for several minutes or an
insufficient number of satellites are received to determine
a position fix, a message will appear, prompting you to
initialize the receiver. This allows you to specify a starting
location from which to search for satellites, or to enable
the AutoLocate feature. It is also useful if you have
traveled over 500 miles with the receiver off. This
message will automatically appear when you first use your
NavTalk Pilot. The prompt may also appear during
normal use if the antenna is shaded or the unit is used
indoors.
EPE and DOP
The Satellite Status Page also indicates the accuracy of
the position fix, using Estimated Position Error (EPE) and
Dilution of Precision (DOP) figures. DOP measures
satellite geometry quality (i.e., number of satellites
received and where they are relative to each other) on a
scale from one to ten. The lowest numbers are the best
accuracy and the highest numbers are the worst. EPE
uses DOP and other factors to calculate an estimated
position error, in feet or meters.
Using the Map to
Initialize