Garmin GPS III - Manual (Page 13)

Once the GPS III has calculated a position fix, you’ll usually have anywhere from
five to twelve satellites in view. The receiver will then 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 three-dimensional
(3D) fix, it can maintain a two-dimensional (2D) fix with only three satellites. A
three-dimensional fix means the unit knows its latitude, longitude, and altitude, while
a two-dimensional fix means the unit knows only its latitude and longitude.
Initializing Your GPS III
To initialize the GPS III, take the receiver outside and find an open area where the
antenna has a clear view of the sky. You may either hold the receiver at a comfortable
height with the antenna pointing up (see page 4), or mount the receiver on the dash of
a vehicle (Appendix A) or on a bike. (Likewise, when you use your GPS III in a
vehicle, make sure the antenna is pointing up.)
To turn the GPS III on, press and hold the red power key.
The Welcome Page will be displayed while the unit conducts a self test. Once
testing is complete, the Welcome Page will be replaced by a warning page, then by the
Satellite Status Page. A message will inform you to “select initialization method”. (If the
initialization prompt has not automatically appeared, press MENU and highlight
‘Initialize Position’.)
To initialize your unit:
1. Press ENTER to acknowledge the message and see a list of initialization options.
2. Use the rocker keypad to highlight ‘Use Map’, and press ENTER.
3. Use the rocker keypad to point the map cursor to your approximate location (within 250
miles). You may also wish to use the IN and OUT zoom keys to make it easier to identify
your approximate position.
4. Press ENTER to select the position and begin searching for satellites.
Check the Satellite Status
Page for ‘2D Navigation’ or
‘3D Navigation’ to verify a
position fix.
The Welcome Page is
displayed when the GPS III is
first turned on. During this
time the receiver is conducting
a self test.
5
GETTING STARTED
Initialization
GPS III A 7/21/98 8:51 AM Page 5