Restarting the GPS
Restarting the GPS provides a means of giving the eXplorist information about its
approximate position. Long time GPS receiver users will know this option as initializing. To
understand when you would use this option, a brief explanation of how the eXplorist works
will be helpful.
The GPS constellation consists of 24 satellites and three spares that orbit the earth. At any
given time of the day a different collection of satellites will be overhead. To keep track of
which satellites are in view, the eXplorist has a built-in almanac that uses the present date
and time, along with its approximate position, to “look up” which satellites should be in view.
Every time you turn your eXplorist off, it records, in a special place in its memory, the last
position fix computed. Then when it is turned back on, it assumes that it is still in the same
approximate location and uses this last position fix when doing its “look up” in the almanac.
Now, if you turn your eXplorist off and fly across the country, the next time you turn it back
on it will think it is still at the location where it was turned off and will begin looking for the
satellites that it thinks are overhead. If the satellites are not there, the eXplorist begins
“polling” the skies, trying to determine which satellites are in view. This process can take
time and can appear as if the GPS portion of the eXplorist is not working. Under normal
conditions, the eXplorist will still be able to compute your position, but this can take longer
than normal.
Restart GPS gives you the ability to give the eXplorist its approximate location, hence
speeding up the time to acquire its first fix. Many eXplorist users will never need to use the
Restart GPS option, but it is available should the need arise.
When to use Restart GPS:
• When the eXplorist has been moved more than 500 miles (804.67 km) while turned off.
• When the eXplorist is sluggish and takes more than a few minutes to compute its first
position fix when turned on. (This really isn’t an option that you need to be concerned
about. Thanks to a built-in feature, the eXplorist, when it has trouble computing its
first position fix, automatically asks you to supply your approximate position.)
Restarting the GPS:
1. Press MENU.
2. Use the Arrow joystick to highlight Preferences.
3. Press ENTER.
4. Use the Arrow joystick to highlight Restart GPS.
5. Press ENTER.
Preferences
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