Garmin echoMAP 40 Series, Руководство пользователя и справочник

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Acquiring Satellite Signals
Because the GPS 40 relies on satellite signals to provide
you with navigation guidance, the receiver needs to have an
unobstructed, clear view of the sky for best performance.
What exactly does this mean? In a nutshell, the GPS receiv-
er’s view of the sky will generally determine how fast you
get a position fix, or if you get a fix at all. GPS signals are
relatively weak and do not travel through rocks, buildings,
people, mountains and other significant structures, so you
need to make sure that you’re not standing next to a tall
building or a wall of cliffs when acquiring satellites.
Once the GPS has calculated a position fix, you’ll usual-
ly have anywhere from four to eight satellites in view. The
GPS 40 will now continuously select the best satellites in
view to update your position. If some of the satellites in
view get blocked or “shaded” the receiver can simply use an
alternate satellite to maintain the position fix. Although a
GPS receiver needs four satellites to provide a 3D fix, the
GPS 40 can maintain a 2D fix with only three satellites.
6
Getting Started
Acquiring
Satellites&
Remote
Antenna
Remote Antenna
An optional remote
antenna may be used with
the GPS 40. The remote
antenna will improve the
receiving capabilities of the
unit by magnifying weaker
signals which the built-in
antenna may not be able to
use.
The remote antenna is
attached by plugging it into
the outlet on the back of the
receiver (see above).
To order an antenna use
the order form in Appendix
B or contact your local
GARMIN dealer for more
information.
Obstructed View of the Sky
Clear View of the Sky
GPS 40 XL 8/5/98 8:15 AM Page 6