The system requires three satellites in order to determine a position. This is called a 2D fix. It takes four satellites to determine both position and elevation (your height above sea level - also called altitude.) This is called a 3D fix.
Remember, the unit must have a clear view of the satellites in order to receive their signals. Unlike radio or television, GPS works at very high frequencies. The signals can be blocked easily by trees, covered docks, even your body.
Never use this GPS receiver while operating a vehicle!
Like most GPS receivers, this unit doesn’t have a compass or any other navigation aid built inside. It relies solely on the signals from the satellites to calculate a position. Speed, direction of travel, and distance are all calculated from position information. Therefore, in order for it to determine direction of travel, you must be moving and the faster, the better. This is not to say that it won’t work at trolling speeds - it will. There will simply be more “wandering” of the data shown on the display.
If you want better performance, many manufacturers (including Lowrance) sell a DGPS receiver that attaches to your GPS receiver. The DGPS sys- tem transmits correction signals that increase the accuracy to about 10 meters. The DGPS receiver takes signals from these
Generally, you find that using your GPS receiver without DGPS 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 available, such as a 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 camp, for example. It’s up to you to safely navigate around obstacles, no matter how you’re using this product.
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