2-69Viper Chart Plotting InstructionsMap ScreenThis section will attempt to familiarize the operator with the features and functions of thissystem. The Medallion Navigation system uses GPS (Global Positioning System)satellites, and a map database to calculate and display route directions. The GPS is basedon satellites which orbit the earth and continuously emit signals. The GPS receiverlocated on the boat receives those signals and calculates, based on the signals, its distancefrom the respective satellites. This information is used to calculate your currentgeographic position. The signals of at least three satellites are needed to determine thecurrent location. When entering the Navigation system, the screen below is the firstscreen that is displayed.Main Map ScreenWhen entering the Navigation area, this is the first screen that comes up. Each section ofthe screen is highlighted above and described below.CURRENT LOCATION — This image shows the current location of the boat.ZOOM LEVEL — This bar shows the zoom distance across the screen. In the exampleabove the distance from the left of the screen to the right of the screen is 1 nautical mile.This can be adjusted from 0.1 to 4000 nautical miles by pressing the + or – buttons.GPS LOCATION — This area of the screen shows the coordinates from the GPSantenna. This can be configured to display 1. Degrees, 2. Degrees, Minutes, 3. Degrees,Minutes, Seconds.GAUGE SCREEN — This area of the screen shows up to seven informational gaugescreens. This gauge screen section can be turned on or off in the SETUP menu(FULL/GAUGE).