Garmin G3X Touch, Maintenance Manual

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Maintenance Manual 190-02472-02
G3X Touch EFIS Part 23 AML STC Revision 2
Page B-15
B.8 Antennas
This section contains general information for interfaced GPS, GPS/WAAS, SXM, and ADS-B antennas.
This STC provides installation approval only for the Garmin glareshield-mounted GPS Antenna (011-
04036-00), refer to the
G3X Touch EFIS Part 23 AML STC Installation Manual (190-02472-01) for
installation guidance. All other antennas are approved as interface only and require separate installation
approval.
A minimum of one GPS antenna is required for G3X installations as the connected GDU (PFD) will share
GPS data with the second GDU (if installed). Additional GPS antennas may be used for redundancy but
are not required.
Table B-7 – Supported GPS & SXM Antennas
Make & Model P/N
Approved G3X
Function
LRU
Connection
Mounting
Comant 2480-201
(GPS/VHF Com) CI 2480-201 GPS GDU 4X0 Blade antenna, external
Garmin Glareshield GPS
Antenna 011-04036-
00 GPS GDU 4X0 Glareshield mounted via hook &
loop or screws
Garmin GA 56 011-00134-
00 GPS GDU 4X0 Stud mount, teardrop, external
Garmin GA 37
(GPS/SXM) 013-00245-
00 SXM GDL 51R/52R ARINC 743, external
Garmin GA 55 011-01033-
00 SXM GDL 51R/52R Stud-mount, teardrop, external
Garmin GA 55A 011-01153-
00 SXM GDL 51R/52R Through-mount, ARINC 743,
external
The GPS antenna interface on the GDL 5XR is not used in this STC.
Only the SXM connection to the GA 37 antenna is approved in this STC. The GPS connection to the GA
37 is not compatible with any G3X LRUs but might be used for other installed equipment under their
respective interface approvals.
Also note that if a previously installed G5 is connected to a GPS antenna mounted externally on the
airframe, that antenna must be disconnected when the G5 is used as a standby instrument for G3X. It
may be possible to repurpose the external antenna for other avionics if it is compatible under their
respective interface approvals.
The GPS antenna should provide a gain of 16 to 25 dB. The GDU 4X0 supplies power to the antenna at
4.5-5.5 VDC with a maximum current of 50 mA.
The following information describes antenna performance requirements for proper system functionality.
Table B-8 – GPS or GPS/WAAS Antenna Minimum Requirements
Characteristics
Specifications
Frequency Range 1565 to 1585 MHz
Gain 16 to 25 dB typical, 40 dB max.
Noise Figure <4.00 dB
Nominal Output Impedance 50 Ω
Supply Voltage 4.5 to 5.5 VDC
Supply Current up to 50 mA
Output Connector BNC or TNC