Garmin GNC 420W Pilots Guide - Page 170

SECTION 9 AUX PAGES • 'Position/Map Datum' - Configures position readout information to the desired position format. The map datum used in the GNC 420 is WGS 84. Note that using a map datum that does not match the charts can result in significant differences in position information. When using the paper charts for reference only, the GNC 420 still provides correct navigation guidance to the waypoints contained in the database, regardless of datum differences. • 'Date/Time' - Provides settings for time format (local or UTC; 12- or 24-hour) and time offset. The time offset is used to define current local time. UTC (also called GMT or Zulu) date and time are calculated directly from the GPS satellites' signals and cannot be changed. To use local time, simply designate the offset by adding or subtracting the correct number of hours. Setup 1 Page: Airspace Alarms Setting the airspace warning messages or changing the altitude buffer: 1) Select 'Airspace Alarms' from the Setup 1 Page (Figure 9-55), using the steps described at the beginning of this section. Figure 9-55 Airspace Alarms Highlighted 2) Turn the large right knob to highlight the 'On'/'Off' field next to the desired airspace type. 'Other SUAs' includes alert, caution, danger, training, and warning areas. 3) Turn the small right knob to select 'On' or 'Off', as desired (Figure 9-56). Press the ENT Key to accept the selection. Figure 9-56 TWR/CTL Zone Alarm Window 9-22 GNC 420(A) Pilot's Guide and Reference 190-00140-20 Rev. K