Garmin GPS 90 - Manual (Page 71)

The first time you power up your new GPS 90 is an
i m p o rtant step in getting the best possible GPS perf o r-
mance. The receiver must be given an opportunity to
collect satellite almanac data and establish its present
position. This initialization process can take 7 1/2 to 15
minutes and is only necessary for first time operation or
after memory loss. Once your GPS 90 has been properly
initialized, you should acquire satellites and obtain a
position within a few minutes each time you power up.
Your GPS 90 is shipped in AutoLocate mode, which is
designed to let the receiver ‘find itself’ without using its
last known position (you don’t need to worry about
what lat/lon is currently displayed on the Position Page,
as the unit is not using that information to calculate your
present position). AutoLocate works best when:
• The unit’s portable antenna is in the proper orienta-
tion (see page 65) and has a clear view of the sky
from horizon to horizon in all directions. Stay away
from all buildings, heavy tree cover and other struc-
tures that may block satellite signals.
• The unit is not moving during initialization. Let the
receiver find an initial position before you take off.
• You wait for an initial position to be computed. If
you turn the unit off before acquiring a position, it
may increase the time to first fix the next time you
power the unit up.
If you want to speed up the initialization process, you
can manually enter your present position through the
initial position reference (see page 44) or on the Position
Page (see page 36). Keep in mind that manually entering
a latitude and longitude or position re f e rence will take
the unit out of AutoLocate mode, and rely on your entry
to look for the proper set of satellites (make sure you
enter the coordinates accurately).
If you experience trouble acquiring satellites or
obtaining a position fix, refer to the troubleshooting sec-
tion in Appendix D.
63
Appendix A
Initialization
Initializing Your
GPS 90
To initialize your unit
for first time use:
• Rotate the portable
antenna so it is per-
pendicular to the
ground (see page 64).
If you’re using the
suction cup mount,
position the antenna
so has the best possi-
ble view of the sky, as
perpendicular to the
ground as your wind-
screen will allow (see
page 65).
• Press and hold the
red power key for
two seconds.
• Remain in the same
location until the GPS
90 has calculated a
position (the Status
page will be replaced
by the Position page
if no other buttons
have been pressed
during acquisition).
gps 90 manual 8/6/98 10:01 AM Page 63