Learning About Gps; Common Gps Terms; What Is Differential Gps (Dgps); Differential Field - Garmin West Marine 276C Plus Owner's Manual

Learning about GPS

The Global Positioning System (GPS) is a satellite-based navigation
system made up of a network of 24 satellites placed into orbit by the
United States Department of Defense.
GPS was originally intended for military applications, but in the
1980s, the government made the system available for civilian use.
GPS works in any weather conditions, anywhere in the world, 24
hours a day. There are no subscription fees or setup charges to use
GPS. For more information, refer to the Garmin Web site at www.
garmin.com and also read the GPS Guide for Beginners, which can
be found on the Web site at http://www.garmin.com/aboutGPS/
manual.html.

Common GPS Terms

Initialization—the first time a GPS receiver orients itself to its
current location and collects data. After the receiver is initialized, it
remembers its location and acquires a position more quickly.
Position—an exact, unique location based on geographic
coordinates (Latitude and Longitude).
Route—A group of waypoints entered into the GPS receiver in the
sequence you desire to navigate them.
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Waypoint—a location you store in your GPS. It may be a
checkpoint on a route or a significant ground feature, such as your
campsite or favorite fishing spot.

What is Differential GPS (DGPS)?

The United States and Canadian governments (among others) have
set up Differential GPS (DGPS) stations to transmit correction
signals. They are operational in coastal areas and on many navigable
river systems.
The DGPS system is available for use without a fee, but you do need
additional equipment (a beacon receiver compatible with the RTCM
format sentences supported by your Garmin GPS) to receive DGPS
signals.
Refer to the United States Coast Guard's Web site (http://www.
navcen.uscg.gov/) for locations and status of the differential stations.

Differential Field

Differential receiver status is indicated in the bottom left field of the
GPS page and will show one of the following conditions:
• None: No optional beacon receiver is attached or enabled in
the Com 1 or 2 tab of the Main Menu or WAAS is turned Off.
• Searching for WAAS: WAAS is enabled and the receiver is
searching for WAAS signals.
A > L GPS
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