Garmin GDL 90 User manual

GDL 90 UAT Data Link Sensor
Installation Manual
April 2004
560-1049-00 Rev B

2004 Garmin Ltd. or its subsidiaries. All rights reserved. Printed in the U.S.A.
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GDL 90 Installation Manual i
HISTORY OF REVISIONS
Revision Date Description
-- 3/17/04 Initial release
A 4/07/04 Update environmental categories (1.3.3, A.1), FCC waiver (1.4.3),
APM p/n (Table 1-3). Add missing lines (Figure 2-1), APM weight
(Table 2-6), APM environmental qualification form (A.2).
B 4/30/04 Remove “STC Pending watermark”. Clarify output of data (1.2). Add
transmitter caution (1.3.7.2, 2.1, 2.5.2, 2.6.2, 2.8.1, 3.2.2, 4.). Add
washer to install kit (Table 1-3). Limit APM wire length to 4 inches,
clarify APM tests, update lightning categories (2.5.2, 2.8.2, A.1, A.2,
Fig C-1). Add exploded-view diagrams (Fig. 2-4, 2-5). Correct MX20
manual refs (4.2.2, 4.3.1.2.2).
ORDERING INFORMATION
To receive additional copies of GDL 90 publications, order the following part numbers:
GDL 90 Installation Manual 560-1049-xx
UAT Antenna Installation Guide 560-0215-xx
A-33 GPS Antenna Installation Guide 560-0949-xx
A-34 GPS Antenna Installation Guide 560-5047-xx
GDL 90 Product CD 140-0063-xx

ii GDL 90 Installation Manual
List of Effective Pages
Page Rev Page Rev Page Rev Page Rev Page Rev
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2-6 B C-1 --
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2-12 B
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Table of Contents
GDL 90 Installation Manual 560-1049-00 Rev B iii
TABLE OF CONTENTS
1GENERAL INFORMATION ................................................................................................................................. 1-1
1.1 ABOUT THIS MANUAL .................................................................................................................................. 1-1
1.1.1 MANUAL ORGANIZATION......................................................................................................................... 1-1
1.1.2 SCOPE ...................................................................................................................................................... 1-1
1.2 EQUIPMENT DESCRIPTION............................................................................................................................. 1-2
1.2.1 FEATURES ................................................................................................................................................ 1-2
1.2.2 SYSTEM INTERFACES ............................................................................................................................... 1-2
1.3 SPECIFICATIONS ............................................................................................................................................ 1-4
1.3.1 ELECTRICAL............................................................................................................................................. 1-4
1.3.2 PHYSICAL................................................................................................................................................. 1-4
1.3.3 ENVIRONMENTAL..................................................................................................................................... 1-4
1.3.4 GPS/WAAS RECEIVER PERFORMANCE................................................................................................... 1-5
1.3.5 UAT PERFORMANCE ............................................................................................................................... 1-5
1.3.6 AVIONICS INTERFACES............................................................................................................................. 1-6
1.3.7 ANTENNA REQUIREMENTS....................................................................................................................... 1-7
1.4 REGULATORY COMPLIANCE.......................................................................................................................... 1-9
1.4.1 TSO AND ADVISORY CIRCULAR REFERENCES ......................................................................................... 1-9
1.4.2 TSO AUTHORIZATION.............................................................................................................................. 1-9
1.4.3 FCC GRANT OF EQUIPMENT AUTHORIZATION ......................................................................................... 1-9
1.4.4 GDL 90 STC AUTHORIZATION .............................................................................................................. 1-10
1.5 UNPACKING THE EQUIPMENT...................................................................................................................... 1-10
1.6 PACKAGE CONTENTS .................................................................................................................................. 1-10
1.7 DEFINITIONS &ACRONYMS ........................................................................................................................ 1-11
2INSTALLATION ................................................................................................................................................. 2-1
2.1 PRE-INSTALLATION INFORMATION................................................................................................................ 2-1
2.2 INSTALLATION OVERVIEW ............................................................................................................................ 2-1
2.3 MATERIALS NOT SUPPLIED........................................................................................................................... 2-1
2.3.1 MATERIALS REQUIRED BUT NOT SUPPLIED ............................................................................................. 2-1
2.4 SPECIAL TOOLS REQUIRED ........................................................................................................................... 2-2
2.5 EQUIPMENT MOUNTING................................................................................................................................2-3
2.5.1 CABLING AND WIRING ............................................................................................................................. 2-3
2.5.2 MOUNTING TRAY INSTALLATION ............................................................................................................. 2-3
2.5.3 UNIT INSERTION &REMOVAL .................................................................................................................. 2-7
2.6 ANTENNA INSTALLATION AND CONNECTIONS .............................................................................................. 2-7
2.6.1 GPS ANTENNA......................................................................................................................................... 2-8
2.6.2 UAT ANTENNAS ...................................................................................................................................... 2-9
2.7 ELECTRICAL CONNECTIONS ........................................................................................................................ 2-10
2.7.1 INTERFACE CONNECTOR DEFINITION ..................................................................................................... 2-11
2.8 FUNCTIONAL DESCRIPTIONS ....................................................................................................................... 2-14
2.8.1 POWER................................................................................................................................................... 2-14
2.8.2 MICRO AIRCRAFT PERSONALITY MODULE (µAPM) .............................................................................. 2-14
2.8.3 STATUS LEDS........................................................................................................................................ 2-14
2.8.4 DISCRETE OUTPUT ................................................................................................................................. 2-15
2.8.5 DISCRETE INPUTS................................................................................................................................... 2-16
2.8.6 SERIAL INTERFACES............................................................................................................................... 2-17
2.8.7 AUDIO.................................................................................................................................................... 2-18
2.8.8 SUPPRESSION OUTPUT ........................................................................................................................... 2-18
2.9 WEIGHT AND BALANCE .............................................................................................................................. 2-19
2.10 ELECTRICAL LOAD ANALYSIS..................................................................................................................... 2-21
3LIMITATIONS ................................................................................................................................................... 3-1
3.1 OPERATION................................................................................................................................................... 3-1
3.2 INSTALLATION .............................................................................................................................................. 3-1
3.2.1 GPS ANTENNA......................................................................................................................................... 3-1

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iv 560-1049-00 Rev B GDL 90 Installation Manual
3.2.2 UAT ANTENNA ........................................................................................................................................3-1
3.2.3 ANTENNA INSTALLATION –GENERAL ......................................................................................................3-1
3.2.4 EQUIPMENT INTERFACED TO THE GDL 90................................................................................................3-2
3.2.5 PRESERVATION OF PREVIOUS SYSTEMS....................................................................................................3-2
4POST INSTALLATION CONFIGURATION &CHECKOUT PROCEDURES............................................................4-1
4.1 MOUNTING AND WIRING CHECK ...................................................................................................................4-1
4.2 EQUIPMENT SETUP AND CONFIGURATION .....................................................................................................4-1
4.2.1 MAINTENANCE MODE ..............................................................................................................................4-2
4.2.2 MX20 SETUP ............................................................................................................................................4-7
4.3 EQUIPMENT OPERATIONAL/FUNCTIONAL TEST .............................................................................................4-7
4.3.1 SYSTEM CHECKOUT –GROUND CHECKS..................................................................................................4-7
5TROUBLESHOOTING .........................................................................................................................................5-1
5.1 TROUBLESHOOTING PROCEDURE ..................................................................................................................5-1
5.2 CONTACTING THE FACTORY FOR ASSISTANCE ..............................................................................................5-2
6PERIODIC MAINTENANCE ................................................................................................................................6-1
6.1 EQUIPMENT CALIBRATION ............................................................................................................................6-1
6.2 CLEANING .....................................................................................................................................................6-1
6.3 BATTERY REPLACEMENT ..............................................................................................................................6-1
APPENDIX A -CERTIFICATION DATA....................................................................................................................... 1
A.1 GDL 90 ENVIRONMENTAL QUALIFICATION......................................................................................................1
A.2 MICRO APM ENVIRONMENTAL QUALIFICATION ..............................................................................................2
APPENDIX B -TROUBLESHOOTING FLOWCHARTS .................................................................................................. 1
APPENDIX C -INTERCONNECT DIAGRAMS .............................................................................................................. 1
APPENDIX D-CONSTRUCTION &VALIDATION OF STRUCTURES............................................................................... 1
LIST OF TABLES
TABLE 1-1. TSO AUTHORIZATION.............................................................................................................1-9
TABLE 1-2. PACKAGE CONTENTS ............................................................................................................1-10
TABLE 1-3. INSTALLATION KIT CONTENTS (PN 424-6081-100) .............................................................1-10
TABLE 1-4. OPTIONAL PARTS ..................................................................................................................1-11
TABLE 2-1. CRIMP TOOL FOR P/N 245-0027 .............................................................................................2-2
TABLE 2-2. INTERFACE CONNECTORS .....................................................................................................2-10
TABLE 2-3. CRIMP CONTACT SPECIFICATIONS........................................................................................2-10
TABLE 2-4. MAIN SYSTEM CONNECTOR PIN-OUT (P1)...........................................................................2-12
TABLE 2-5. I/O CONNECTOR PIN-OUT (P2) .............................................................................................2-13
TABLE 2-6. UNIT WEIGHTS......................................................................................................................2-19
TABLE 2-7. UNIT POWER LOADS .............................................................................................................2-21
TABLE 4-1. MAINTENANCE MODE COMMANDS ........................................................................................4-2
TABLE 4-2. DATA ITEMS FOR APM INITIALIZATION .................................................................................4-4
TABLE 4-3. GDL 90 POST-INSTALLATION CHECKOUT LOG ....................................................................4-10
TABLE 5-1. TROUBLESHOOTING GUIDE.....................................................................................................5-1
TABLE D-1. STATIC TEST LOAD ...................................................................................................................1
LIST OF ILLUSTRATIONS
FIGURE 1-1. SAMPLE GDL 90 SYSTEM DIAGRAM .....................................................................................1-3
FIGURE 2-1. SINGLE ENGINE AIRCRAFT GDL 90 MOUNTING LOCATIONS................................................2-4
FIGURE 2-2. MULTI-ENGINE AIRCRAFT GDL 90 MOUNTING LOCATIONS ................................................2-4
FIGURE 2-3. GDL 90 MOUNTING TRAY &DIMENSIONS ...........................................................................2-5

Table of Contents
GDL 90 Installation Manual 560-1049-00 Rev B v
FIGURE 2-4: GDL 90 TRAY &CONNECTORS ............................................................................................ 2-6
FIGURE 2-5: GDL 90 TRAY &OPTIONAL COVER ..................................................................................... 2-7
FIGURE 2-6. ANTENNA PLACEMENT.......................................................................................................... 2-8
FIGURE 2-7. RIGHT ANGLE COAX CONNECTOR ASSEMBLY ..................................................................... 2-9
FIGURE 2-8. REAR CONNECTOR LAYOUT................................................................................................ 2-11
FIGURE 2-9. 15-PIN CONNECTOR ............................................................................................................ 2-12
FIGURE 2-10. 37-PIN CONNECTOR........................................................................................................... 2-13
FIGURE 2-11. GDL 90 CENTER OF GRAVITY........................................................................................... 2-20
FIGURE C-1. INTERCONNECT DIAGRAM FOR INSTALLATION W/MX20 MFD.............................................. 3
FIGURE D-2. UPWARD STATIC LOAD TEST .................................................................................................. 2
FIGURE D-3. FORWARD STATIC LOAD TEST ................................................................................................ 2

Table of Contents
vi 560-1049-00 Rev B GDL 90 Installation Manual
NOTES

General Information
GDL 90 Installation Manual 560-1049-00 Rev B 1-1
1 GENERAL INFORMATION
1.1 ABOUT THIS MANUAL
This manual describes the installation and checkout procedures for the GDL 90 UAT Data Link Sensor.
It is intended for use by persons certified by the Federal Aviation Administration (FAA) to install
avionics devices.
1.1.1 MANUAL ORGANIZATION
Provides GENERAL INFORMATION about the GDL 90 unit. TSO certification
information is also included in this section.
Includes INSTALLATION PROCEDURES.
Includes LIMITATIONS for the equipment and installation.
Includes POST-INSTALLATION CONFIGURATION AND CHECKOUT.
Includes TROUBLESHOOTING information.
Includes PERIODIC MAINTENANCE requirements.
Includes CERTIFICATION DATA.
Includes TROUBLESHOOTING FLOWCHARTS.
Includes INTERCONNECT DIAGRAMS.
Includes CONSTRUCTION &VALIDATION of structures.
1.1.2 SCOPE
The information in this manual is STC approved. Only the equipment interfaces covered in this manual
are within the scope of this STC. Other equipment may be suitable for use with the GDL 90, but use of
such equipment is beyond the scope of this STC – additional FAA approval may be required if equipment
not covered in this manual is used to interface to the GDL 90.
Antenna installation in the pressure vessel of pressurized aircraft is also beyond the scope of the GDL 90
STC. Additional manufacturer's data may be necessary and FAA approval may be required to cover the
installation of the antenna.
Refer to Section 3 Limitations for additional information.
SECTION 1
SECTION 2
SECTION 3
SECTION 4
SECTION 5
SECTION 6
APPENDIX A
APPENDIX B
APPENDIX C
APPENDIX D

General Information
1-2 560-1049-00 Rev B GDL 90 Installation Manual
1.2 EQUIPMENT DESCRIPTION
The Garmin GDL 90 is a remote-mounted product that contains a GPS/WAAS engine and a Universal
Access Transceiver. The GDL 90 will transmit ownship data via the UAT data link. It will receive data
from other UAT-equipped aircraft, as well as FIS-B weather – the received data may be output to an
appropriate display.
1.2.1 FEATURES
The features of the GDL 90 UAT Data Link Sensor include:
•10-40 VDC Power Capability
•978 MHz Universal Access Transceiver data link radio designed to support ADS-B, TIS-B and FIS-B
airborne and ground applications
•GPS/WAAS engine for state-of-the-art fast, accurate navigation and precision approach (15-channel,
3 WAAS decoders, 5 Hz update of position, time, and velocity)
•Interface to Altitude Encoder via RS232 bus
•Interface to Garmin MX20 Multi-function Display
1.2.2 SYSTEM INTERFACES
The interfaces for a typical GDL 90 are shown in Figure 1-1. The available interfaces are further
described in the following sections.

General Information
GDL 90 Installation Manual 560-1049-00 Rev B 1-3
Figure 1-1. Sample GDL 90 System Diagram

General Information
1-4 560-1049-00 Rev B GDL 90 Installation Manual
1.2.2.1 Multi-function Display
The GDL 90 is capable of driving one MX20 Display with traffic and weather information.
1.2.2.2 Altitude Encoder
The GDL 90 is capable of interfacing to an altitude encoder to obtain altitude data via a RS232 bus.
1.2.2.3 Annunciator Outputs and Switch Inputs
The GDL 90 can drive one external annunciator lamp and receive inputs from various switches to control
its operation.
1.2.2.4 Maintenance Interface
The GDL 90 has a RS232 communication port that is used to configure and check status of the GDL 90
system. Refer to other sections of this manual for more description.
1.2.2.5 Audio Alert
The GDL 90 has one 500 Ωaudio output that can be connected to an audio panel to provide audible
messages to the pilot. This is a future feature and currently not operational.
1.3 SPECIFICATIONS
This section includes detailed electrical, physical, environmental and performance specifications for the
GDL 90.
1.3.1 ELECTRICAL
Input voltage.................................................. 10 - 40 VDC
Input current (typical) ................................... 1.5 A at 14 VDC
750 mA at 28 VDC
1.3.2 PHYSICAL
Height............................................................ 7.42 inches (18.84 cm)
Width............................................................. 3.54 inches (8.97 cm)
Depth............................................................. 12.64 inches (32.11 cm)
Weight........................................................... 6.4 lb (2.9 kg) with mounting tray
1.2 lb (0.54 kg) mounting tray only
1.3.3 ENVIRONMENTAL
The GDL 90 is designed and tested to meet appropriate categories as shown in the Environmental
Qualification Form included in Appendix A.
Operating temperature................................... -20°C to +55°C
Storage temperature ...................................... -55°C to +85°C

General Information
GDL 90 Installation Manual 560-1049-00 Rev B 1-5
Temperature variation....................................5°C per minute
Humidity ........................................................95% at 65°C
Maximum continuous altitude .......................55,000 feet
Decompression ..............................................55,000 feet
External Cooling............................................Not required with internal fans operational and
vents unobstructed
Water-resistant...............................................with vertical mounting and optional cover
1.3.4 GPS/WAAS RECEIVER PERFORMANCE
TSO Compliance ...........................................TSO-C145a (RTCA/DO-229C)
Number of channels.......................................15 (12 GPS and 3 GPS/WAAS/SBAS)
Frequency ......................................................1575.42 MHz L1, C/A code
Sensitivity (acquisition).................................-116 dBm to -134.5 dBm GPS
-116 dBm to -135.5 dBm WAAS
Sensitivity (drop lock) ...................................-144 dBm
Dynamic range...............................................> 20 dB
Lat/Long position accuracy ...........................<1 meter RMS typical with WAAS
(horizontal/vertical)
Velocity .........................................................1000 knots maximum (above 60,000 ft)
TTFF (time to first fix)..................................1:45 min. typical with current almanac, position, and
time
Reacquisition ....................................10 seconds typical
Position update interval ....................0.2 sec (5 Hz)
1 pps (pulse per second) ...................±275 nsec of UTC second
Datum ...............................................WGS-84
SATCOM compatibility ...................Compatible on aircraft equipped with SATCOM
Antenna power supply ......................35 mA typical, 40 mA max at 4.7 VDC
1.3.5 UAT PERFORMANCE
TSO Compliance ...........................................TSO-C154 (RTCA/DO-282)
Frequency ...................................................... 978.00 MHz
Transmit Power.............................................. 50 W (+47 dBm)
Frequency Tolerance .....................................+/- 20 PPM
Modulation.....................................................Continuous Phase FSK, h = 0.6, Raised Cosine
shaping, a = 0.5
Data Rate .......................................................1.04 Mbps
99% Power Bandwidth ..................................1.3 MHz

General Information
1-6 560-1049-00 Rev B GDL 90 Installation Manual
60 dB bandwidth ........................................... 3.3 MHz (estimated)
Receiver Sensitivity ...................................... -96 dBm for 90% MSR
1.3.6 AVIONICS INTERFACES
Annunciator Outputs..................................... Open collector output capable of sinking up to 400
mA for turning ON annunciator lamp
Multi-function Display.................................. RS-422 asynchronous serial
Altitude Encoder ........................................... RS-232 asynchronous serial

General Information
GDL 90 Installation Manual 560-1049-00 Rev B 1-7
1.3.7 ANTENNA REQUIREMENTS
1.3.7.1 GPS Antennas
1.3.7.1.1 A-33 (590-1104)
Early production runs of PN 590-1104 were marked with TSO-C129a. This antenna was re-qualified to
TSO-C144 with no changes to the antenna. P/N 590-1104 antennas marked with TSO-C129a
identification are identical to those marked with TSO-C144.
Applicable TSO: .........................................................TSO-C144 (RTCA/DO-228 with Change No. 1)
Frequency: .....................................................1575 MHz
Polarization:...................................................Right Hand Circular
Axial Ratio:....................................................3 dB Max at bore site
Radiation Coverage: ......................................Elevation Angle Minimum Gain
>15º -2.0 dBic
10º -3.0 dBic
5º -4.5 dBic
0º -7.5 dBic
Finish: ............................................................Polyurethane Enamel
Weight: .........................................................3.9 oz. (0.11 kg)
Height: ..........................................................0.61 inches (1.55 cm)
Operating Temperature: ................................-55°C to +85°C
Operating Altitude: .......................................55,000 feet (16,764m) max.
Amplifier:
Gain.........................................................26.5 dB ±2 dB
Noise Figure:...........................................2.5 dB Max
Impedance: ..............................................50 ohms
VSWR (Dry): ..........................................< 1.5:1
VSWR (Rain):.........................................< 2.0:1
Band Rejection:.......................................35 dB
Power Handling: .....................................1 Watt
Voltage:...................................................5 VDC ±10%
Current: ...................................................35 mA nominal, 40 mA max.
L1 Filter Bandwidth .........................1575 ±20 MHz (3 dB)
+110, -210 MHz (60dB)
Group Delay (3dB bandwidth)................27 ±10 nanosecond
Pass Band Ripple (3dB bandwidth) …….0.2 dB max

General Information
1-8 560-1049-00 Rev B GDL 90 Installation Manual
1.3.7.1.2 A-34 (590-1112)
Early production runs of PN 590-1112 were marked with TSO-C129a. This antenna was re-qualified to
TSO-C144 with no changes to the antenna. P/N 590-1112 antennas marked with TSO-C129a
identification are identical to those marked with TSO-C144.
Applicable TSO: ........................................................ TSO-C144 (RTCA/DO-228 with Change No. 1)
Frequency:..................................................... 1575 MHz
Polarization: .................................................. Right Hand Circular
Axial Ratio:................................................... 3 dB Max at bore site
Radiation Coverage:...................................... Elevation Angle Minimum Gain
>15º -2.0 dBic
10º -3.0 dBic
5º -4.5 dBic
0º -7.5 dBic
Finish:............................................................ Polyurethane Enamel
Weight: ......................................................... 7.0 oz. (0.2 kg)
Height: .......................................................... 0.66 inches (1.76 cm)
Operating Temperature: ............................... -55°C to +85°C
Operating Altitude: ...................................... 55,000 feet (16,764m) max.
Amplifier:
Gain ........................................................ 26.5 dB ±2 dB
Noise Figure: .......................................... 2.5 dB Max
Impedance:.............................................. 50 ohms
VSWR (Dry):.......................................... < 1.5:1
VSWR (Rain): ........................................ < 2.0:1
Band Rejection: ...................................... 35 dB
Power Handling:..................................... 1 Watt
Voltage: .................................................. 5 VDC ±10%
Current:................................................... 35 mA nominal, 40 mA max.
L1 Filter Bandwidth................... ............ 1575 ±20 MHz (3 dB)
+110, -210 MHz (60dB)
Group Delay (3dB bandwidth) ............... 27 ±10 nanosecond
Pass Band Ripple (3dB bandwidth) …….0.2 dB max

General Information
GDL 90 Installation Manual 560-1049-00 Rev B 1-9
1.3.7.2 UAT Antenna
The GDL 90 requires a UHF antenna meeting the following specifications:
•Standard 50Ωvertically polarized antenna with a VSWR < 1.7:1 at 978 Mhz
•TSO-C66, C74, C112 or C154 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 90 with no RF terminations on the Top or Bottom UAT Antenna
ports can result in equipment damage. Always operate the GDL 90 with the Top and
Bottom UAT Antenna ports terminated with a VSWR ratio of 3.0:1 or less.
1.4 REGULATORY COMPLIANCE
1.4.1 TSO AND ADVISORY CIRCULAR REFERENCES
•TSO-C154 Universal Access Transceiver (UAT) Automatic Dependent Surveillance –
Broadcast (ADS-B) Equipment Operating on the Frequency of 978 MHz.
•TSO-C145A Airborne Navigation Sensors using GPS Augmented by WAAS
NOTE
Unauthorized changes or modifications to the GDL 90 may void the compliance to
required regulations and authorization for continued equipment usage.
1.4.2 TSO AUTHORIZATION
Table 1-1. TSO Authorization
Function TSO
Minimum Performance
Standard
Software
RTCA/DO-178B
UAT
Transceiver
TSO-C154, Class A1H, B1 RTCA/DO-282
Level B,C
GPS/WAAS TSO-C145A, Class 1 RTCA/DO-229C, Class 1 Level B
1.4.3 FCC GRANT OF EQUIPMENT AUTHORIZATION
•FCC regulations for UAT are not yet finalized. The GDL 90 meets the proposed FCC
regulations and international agency proposed regulations. Garmin AT has applied for a waiver
for UAT use in the United States during the interim until FCC regulations are adopted. Testing
was completed on the GDL 90 Universal Access Transceiver and documented in PD3621, GDL
90 UAT FCC Certification Report. The data show compliance with FAA TSO-154 and FCC
proposed rules to Parts 2 and 87 as commented in Docket No. 01-289. The data further

General Information
1-10 560-1049-00 Rev B GDL 90 Installation Manual
demonstrate that the GDL 90 is compatible with existing FCC regulations in 47 CFR2 and 47
CFR87.
•Use of UAT for government programs, such as Capstone Phase 1 and Phase 2 in Alaska, has
been fully coordinated with NTIA, and is authorized. In December of 2000, the RTCA created
Working Group 5 of Special Committee 186, to develop and approve the Minimum Operational
Performance Standards for the UAT data link. The effort was completed in June 2002. As part
of this effort, the NTIA has granted Stage 4 spectrum certification for use of the UAT data link
using a radio frequency of 978 MHz.
1.4.4 GDL 90 STC AUTHORIZATION
Refer to the GDL 90 Product CD 140-0063-xx for data regarding GDL 90 STC authorization.
1.5 UNPACKING THE EQUIPMENT
Carefully unpack the equipment. Visually inspect the package contents for any evidence of shipping
damage. Retain all shipping containers and packaging material in case reshipment is necessary.
1.6 PACKAGE CONTENTS
As shipped from the Garmin AT factory, the GDL 90 package includes most necessary items for
installation other than supplies normally available at the installation shop, such as wire and cable ties,
circuit breakers, and required input and output equipment. The items included in the package are listed in
Table 1-2 and Table 1-3. In addition, Table 1-4 lists optional parts that may be needed for non-standard
installations.
Table 1-2. Package Contents
Part # Qty Description
424-6081-1xx 1 GDL 90 Installation Kit (see Table 1-3 for detail)
430-6081-1xx-xxx 1 GDL 90 UAT Data Link Sensor
140-0063-xx 1 GDL 90 Product CD
590-1104 1 A33 GPS Antenna
590-0051 2 UAT Blade Antenna, passive, TNC
Table 1-3. Installation Kit Contents (PN 424-6081-100)
Part # Qty Description
162-0043 3 Connector, coax, RA, PNL MNT
265-0007 3 Retainer Ring, ext,7/16 shaft
240-0008 3 Washer, 0.446 ID 0.56 OD
162-1574 1 Receptacle DSUB 9-pin
162-1575 1 Receptacle DSUB 15-pin
162-1577 1 Receptacle DSUB 37-pin
162-2080 3 Connector, coax, RA, plug clamp, TNC
202-0002 8 Cable tie
224-0404 4 Screw, 4-40 x 1/4 SS flat head Phillips 82 deg.
245-0027 25 Crimp contact, DSUB, 20 to 24 AWG wire
310-0461-00 1 Cover Mounting Tray GDL 90
310-0462-00 1 Mounting Tray GDL 90
430-6200-000 1 Aircraft Personality Module (APM)
660-0014 50 Cable, coax RG400 dbl shld 50-ohm (feet)

General Information
GDL 90 Installation Manual 560-1049-00 Rev B 1-11
Table 1-4. Optional Parts
Part # Description
310-0467-xx Capstone Phase 1 Adapter Plate
500-0290-xx Capstone Phase 1 Adapter Cable
560-1057-xx GDL 90 Capstone Upgrade Instructions
1.7 DEFINITIONS &ACRONYMS
ADC Air Data Computer
AHRS Attitude Heading Reference System
ALT Altitude
APM Aircraft Personality Module
EN Engineering Notice
GPS Global Positioning System
MFD Multi-Function Display
STC Supplementary Type Certificate
TSO Technical Standard Order
UAT Universal Access Transceiver
WAAS Wide Area Augmentation System

General Information
1-12 560-1049-00 Rev B GDL 90 Installation Manual
NOTES