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Learning about gps, O learn about gps, refer to – Garmin GPSMAP 296 User Manual

Page 146

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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

.

Common GPS Terms

Initialize—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 location more quickly.
Location—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 want to navigate them.
Waypoint—a location you store in your GPS.

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 to receive DGPS signals: A beacon receiver

compatible with the RTCM format sentences supported by your

Garmin GPS is needed to use DGPS.
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 shows one of the following conditions:

None—no optional beacon receiver is attached or enabled

on the Interface sub tab on the Main Menu or WAAS is

turned off.

Searching for WAAS—WAAS is enabled and the receiver is

searching for WAAS signal.

Using WAAS—WAAS capability is enabled and the unit is

receiving WAAS corrections.

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GPSMAP 296 Pilot’s Guide

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EARNING

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