9-33190-01007-03 Rev. B Garmin GTN 725/750 Pilot’s GuideForewordGettingStartedAudio &Xpdr CtrlCom/NavFPLDirect-ToProcChartsWpt InfoMapTrafficTerrainWeatherNearestMusicUtilitiesSystemMessagesSymbolsAppendixIndex9.4 Cdi (GTn 750 only)The GTN 750's CDI key is used to couple the GPS or VLOC receiver to theexternal CDI (or HSI). When the external CDI (or HSI) is connected to the GPSreceiver, “GPS” appears below the CDI key in the annunciation bar. When theexternal CDI (or HSI) is being driven by the VLOC receiver, “VLOC” appearsinstead.NOTE: The external CDI (or HSI) must be coupled to the VLOC receiver forapproaches which are not approved for GPS. See the ILS example in theProcedures section for more information.NOTE: GPS phase of flight annunciations (LPV, ENR, etc.) are not applicableto the external CDI (or HSI) when VLOC is active.NOTE: The internal on-screen CDI information is based on GPS data andcannot be used for primary navigation.NOTE: If the unit is not configured for a CDI key, then the “activate GPS missedapproach” will only resume automatic waypoint sequencing. The user mustswitch to GPS navigation, if desired, by using their external source selectionmethod (this is typical an EFIS system).1. The navigation source is annunciated under the CDI key.Touch CDI Key To ToggleNavigation SourceNavigation SourceAnnunciationFigure 9-38 Navigation Source Selection2. Touch the CDI key to toggle between sources.
