Garmin GI 275 Pilot's Manual page 37

• 2D Diff Nav—At least three satellites have been acquired and a two-dimensional location fix
has been calculated, with SBAS corrections applied.
• 3D Nav—At least four satellites have been acquired and a three-dimensional fix has been
calculated.
• 3D Diff Nav—At least four satellites have been acquired and a three-dimensional fix has
been calculated, with SBAS corrections applied.
• Lost Satellite Reception—the receiver is no longer tracking enough satellites for a valid
position fix.
Acquiring Satellites
When the receiver is in the process of acquiring enough satellite signals for navigation, the
receiver uses satellite orbital data (collected continuously from the satellites) and last known
position to determine the satellites that should be in view. "Acquiring Satellites" is indicated as
the solution until a sufficient number of satellites have been acquired for computing a solution.
Satellite Information
Satellites currently in view are shown at their respective signal strengths accessed from the
GPS Signal Strength Button. The 'GPS Signal' Screen can be helpful in troubleshooting weak
(or missing) signal levels due to poor satellite coverage or installation problems. As the GPS
receiver locks onto satellites, a signal strength bar is displayed for each satellite in view, with
the appropriate satellite identification number adjacent to each bar. The progress of satellite
acquisition is shown as indicated by signal bar appearance:
• No bar—Receiver is looking for a satellite
• Green bar—Receiver has found the indicated satellite
190-02246-01 Rev. A
VFR GPS Satellite Signals
Garmin GI 275 Pilot's Guide
System Overview
15