Universal Sonar 2; How Gps And Cartography Work - Humminbird 797C2 Operation Manual

Universal Sonar 2

Your 700 Series™ Fishing System supports Universal Sonar 2, a state-of-the-
art, integrated and protected transducer that is built into the lower unit of
Minnkota trolling motors. With Universal Sonar 2, all wiring is concealed inside
the indestructible composite shaft—out of sight and out of harm's way, with
no clamps, ties, or exposed wires. Universal Sonar 2 features new temperature
sensing and the performance of DualBeam PLUS™ technology (available with
all Humminbird® DualBeam PLUS™ models). An expanded view and greater
bottom detail gives you a totally new perspective of the water below, along
with optimal sonar performance to help you find fish.

How GPS and Cartography Work

Your 700 Series™ Fishing System also supports GPS and chartplotting, and
uses GPS and sonar to determine your position, display it on a grid, and provide
detailed underwater information. The Global Positioning System (GPS) is a
satellite navigation system designed and maintained by the U.S. Department of
Defense. GPS was originally intended for military use; however, civilians may
also take advantage of its highly accurate position capabilities, typically within
+/- 10 meters, depending on conditions. This means that 95% of the time, the
GPS receiver will read a location within 10 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.
GPS uses a constellation of 24 satellites that
continually send radio signals to the earth. Your
present position is determined by receiving signals
from up to 16 satellites and measuring the
distance from the satellites.
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