Garmin GDL 88, Installation Manual

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GDL 88 TSO Installation Manual Page 1-5
190-01122-00 Rev. A
1.3.7 UAT/1090 Requirements
The GDL 88 requires UHF antenna(s) meeting the following specifications:
Vertically polarized
The VSWR produced by the antenna does not exceed 1.7:1 at 978 MHz and 1.5:1 at 1090 MHz.
TSO-C66, TSO-C74, or TSO-C112 antennas that also meet the VSWR specification.
NOTE
Certain types of transponder antennas that utilize very thin radiator elements are only
intended for use at 1030 and 1090 MHz. These types of antennas should be evaluated on
a model-by-model basis to determine their suitability as UAT data link antennas.
CAUTION
Operating the GDL 88 without RF terminations on the top or bottom UAT antenna ports
can result in equipment damage. Always operate the GDL 88 with the top and bottom
UAT antenna ports terminated with a VSWR ration of 3.0:1 or less.
1.3.8 GPS Antenna Requirements
Antenna performance is critical to the GPS/SBAS operation. The antennas listed in Table 1-8 provide
acceptable performance with the GDL 88.
Table 1-8. Approved GPS/SBAS Antennas
Model/Description Conn Type Mfr Part Number
Garmin
Order
Number
GA 35, GPS/WAAS
[1]
TNC
Garmin 013-00235-( )
013-00235-( )
Aero Antenna AT575-93G( )-TNCF-000-RG-27-NM
GA 36, GPS/WAAS TNC
Garmin 013-00244-( )
013-00244-( )
Aero Antenna AT575-126G( )-TNCF-000-RG-27-NM
GA 37, GPS/WAAS/XM TNC
Garmin 013-00245-( )
013-00245-( )
Aero Antenna AT2300-126G( )-TNCF-000-RG-27-NM
A33W, WAAS Antenna TNC
Garmin 013-00261-( )
013-00261-( )
Aero Antenna AT575-332G( )- TNCF-000-RG-27-NM
GPS/VHF Antenna
TNC/BNC
[2]
Comant CI-2580-200 N/A
GPS/VHF Antenna
TNC/BNC
[2]
Comant CI-2728-200 N/A
GPS/XM/VHF Antenna
TNC/TNC/BNC
[3]
Comant CI-2580-410 N/A
GPS/XM/VHF Antenna
TNC/TNC/BNC
[3]
Comant CI-2728-410 N/A
GPS/WAAS Antenna TNC Comant CI-428-200 N/A
GPS/XM Antenna TNC/TNC Comant CI-428-410 N/A
[1] Same mounting hole pattern as GA 56, but GA 35 antenna has a physically larger footprint.
[2] The antenna connector is a TNC type. The VHF connector is a BNC type.
[3] The antenna connector is a TNC type. The XM connector is a TNC type. The VHF connector is a
BNC type.