EPE and DOPThe Satellite Status Page also indicates the accuracy of the position fix, usingEstimated Position Error (EPE) and Dilution of Precision (DOP) figures. DOP mea-sures satellite geometry quality (i.e., number of satellites received and where they arerelative to each other) on a scale from one to ten. The lowest numbers are the bestaccuracy and the highest numbers are the worst. EPE uses DOP and other factors tocalculate a horizontal position error, in feet or meters.Screen BacklightingThe GPS III Pilot’s backlight feature illuminates the display and keypad for auser-defined interval (the default is 15 seconds) after the last key press. There arethree levels of backlighting. When backlighting is on, a bulb icon will appear at thebottom left of the sky view. To adjust the duration of the screen backlighting, referto the operation setup section (see p. 79).To turn the screen backlighting on:1. Cycle through the three levels of backlight by repeatedly pressing the red power key.To turn the screen backlighting off:1. Press the red power key. Whenever the GPS III Pilot’s backlighting is off, the bulbicon disappears from the Satellite Status Page.Satellite Status Page OptionsMany features of the GPS III Pilot are menu driven. Each of the main pages hasan options menu, allowing you to custom tailor the corresponding page to your pref-erences and/or select special features which specifically relate to that page.To display the Satellite Status Page Options, press MENU (with theSatellite Status Page displayed).When screen backlighting ison, a bulb icon will appear inthe lower-left corner of theSatellite Status Page.The Satellite Status PageOptions allow you to enablethe built-in simulator, changethe sky view orientation orinitialize the receiver.30REFERENCESatellite Status Page