Garmin GPSMAP 188C Owner's Manual page 47

Ocean, in a geo-stationary orbit over the equator. Effective use
of the WAAS satellite signal can be limited by your geographic
location in relation to those satellites, now in developmental
service. WAAS satellite signal reception requires an absolute
clear view of the sky and works best when there are no nearby
obstructions such as buildings or mountains.
WAAS satellites are numbered 33 or higher when viewing the sky
view on your GPSMAP 188/188C Sounder. Initial reception of
the WAAS signal can take up to 15-20 minutes, then 1-2 minutes
afterward. When WAAS differential correction has been received
for GPS satellites (numbers 32 or below), a D appears in the
signal bar of the sky view and 2D or 3D Differential appears in the
receiver status. To learn more about the WAAS system, its satellite
positions and current state of development, visit the FAA web site
(http://gps.faa.gov). Because WAAS requires CPU resources of the
GPSMAP 188/188C Sounder to search for and track the satellites,
you can disable the WAAS feature to improve unit performance
if WAAS reception is not available in your area. Refer to the
"Appendix" for more information.
GPSMAP 188/188C Sounder Owner's Manual
To Disable/Enable WAAS capability:
1. From the GPS tab, press MENU.
2. Use the ROCKER to highlight WAAS Off or WAAS On, and
press ENTER.
Highlight WAAS Off, and press ENTER
to disable the WAAS capabilities.
M M > GPS T
AIN ENU AB
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