400W Series Installation Manual Page 4-7190-00356-02 Rev. E4.4 Main Indicator4.4.1 Main Indicator FunctionThe Main Indicator displays both lateral and vertical deviation from selected course, To/Fromindications, lateral and vertical flags and superflags.The “CDI” key on the bezel of the GNS 430W takes the place of remote “NAV/GPS” switches, and isused to toggle between display of GPS and VOR/ILS navigation display on a remote indicator. TheNavigation source is annunciated on the display above the ‘CDI’ key. The Navigation method isoptionally annunciated externally by connecting to the VLOC ANNUNCIATE output (P4001-1) andGPS ANNUNCIATE output (P4001-2). GPS and VOR/ILS navigation may be toggled externally whenthe CDI SOURCE SELECT input (P4001-73) is momentarily grounded. See section 4.5 for moreinformation on the external annunciators and switches.An OBS resolver connection to the GPS is preferred, but not required. For the GNS 430W, an OBSresolver typically is connected to the MAIN OBS inputs for use with the GNS 430W VOR receiver.4.4.2 Main Indicator Electrical Characteristics4.4.2.1 DeviationPin Name Connector Pin I/OMAIN +LEFT P4001 21 OutMAIN +RIGHT (1.65V COMMON) P4001 22 OutMAIN +UP (1.65V COMMON) P4001 27 OutMAIN +DOWN P4001 28 OutThe deviation output is capable of driving up to three 1000 Ω meter loads with ±150 mVDC ±10% forfull-scale deflection. The drive circuit provides for more than full-scale deflection with a maximumcourse deviation output voltage of ±300 mVDC ±10%.4.4.2.2 TO/FROMPin Name Connector Pin I/OMAIN +TO (1.65V COMMON) P4001 25 OutMAIN +FROM P4001 26 OutThe output is capable of driving up to three 200 Ω meter loads. When indicating TO, MAIN +TO is +190±40 mVDC with respect to MAIN +FROM. When indicating FROM, MAIN +TO is -190 ±40 mVDCwith respect to MAIN +FROM. When invalid information is present (Flag IN VIEW) the TO/FROMoutput is 0 ±10 mVDC.4.4.2.3 FlagsPin Name Connector Pin I/OMAIN LATERAL +FLAG P4001 23 OutMAIN LATERAL -FLAG (GROUND) P4001 24 OutMAIN VERTICAL +FLAG P4001 29 OutMAIN VERTICAL -FLAG (GROUND) P4001 30 OutThe Flag output is capable of driving up to three 1000 Ω meter loads. When valid information is present(Flag OUT OF VIEW) the Flag output is 375 ±80 mVDC. When invalid information is present (Flag INVIEW) the Flag will have an output is 0 ±25 mVDC.
