If your PiranhaMAX model includes GPS (Global Positioning System), it will use GPS and sonar to determine your current track, display it on a grid, and provide detailed underwater information.
GPS uses a constellation of satellites that continually send radio signals to the earth. The GPS receiver on your boat receives signals from satellites that are visible to it. Based on time differences between each received signal, the GPS receiver determines its distance to each satellite. With distances known, the GPS receiver mathematically triangulates its own position. With 5 updates per second, the GPS receiver then calculates its velocity and bearing.
GPS was originally intended for military use; however, civilians may also take advantage of its highly accurate position capabilities, typically within +/- 4.5 meters, depending on conditions. This means that 95% of the time, the GPS receiver will read a location within +/- 4.5 meters of your actual position. Your GPS Receiver also uses information from WAAS (the Wide Area Augmentation System), EGNOS (the European Geostationary Navigation Overlay Service), and MSAS (the MTSAT Satellite Augmentation System) satellites if they are available in your area.
PiranhaMAX models that include GPS currently support the following GPS functionality:
•View current track (breadcrumb trail)•View precision speed and heading•Save waypoints. Your Fishfinder can store over 500 waypoints. See Track View for more information.
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