Lowrance electronic LMS-339cDF iGPS GPS Receiver User Manual


 
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this by broadcasting correction signals on GPS frequencies. Your unit
automatically receives both GPS and WAAS signals.
However, there are some fringe areas of the U.S., including parts of
Alaska, that do not yet receive robust WAAS coverage. Continued
WAAS development is planned to extend WAAS coverage in the years
to come.
WAAS boosts the accuracy of land GPS navigation, but the system is
designed for aircraft. The satellites are in a fixed orbit around the
Equator, so they appear very low in the sky to someone on the ground
in North America. Aircraft and vessels on open water can get consis-
tently good WAAS reception, but terrain, foliage or even large man-
made structures can sometimes block the WAAS signal from ground
receivers.
You'll find that using your GPS receiver is both easy and amazingly
accurate. It’s easily the most accurate method of electronic navigation
available to the general public today. Remember, however, that this
receiver is only a tool. Always have another method of navigation avail-
able, such as a map or chart and a compass.
Also remember that this unit will always show navigation information
in the shortest line from your present position to a waypoint, regardless
of terrain! It only calculates position, it can’t know what’s between you
and your destination, for example. It’s up to you to safely navigate
around obstacles, no matter how you’re using this product.
Free Training Aids Available
Now that you know something about the technology that makes this
unit possible, you are ready to start learning how to use that technol-
ogy. This manual will guide you through the process of setting up and
running your unit, but that is only one of many resources available.
If you or a friend has Internet access, visit our web site. Find us at
WWW.LOWRANCE.COM. The site is packed with additional information
on using our products.
For instance, you can learn more about interpreting what you see on
your sonar screen with our free Sonar Tutorial. The tutorial includes
animated illustrations and more pictures of actual sonar returns, all
described in detail. There's even a printer friendly version of the tuto-
rial available on our web. It makes a great supplement to this manual.