Garmin GTX 345R, GTX 345, GTX 335 User manual

GTX 3X5 Part 27 AML

Maintenance Manual

Contains Instructions for Continued Airworthiness for STC SR02124SE

Rotorcraft make, model, registration number, and serial number and accompanying STC configuration information in Appendix A must be completed and saved with rotorcraft permanent records.

190-00734-21

February 2020

Revision 2

© 2020 Garmin International or its subsidiaries All Rights Reserved

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190-00734-21	GTX 3X5 Part 27 AML Maintenance Manual
Rev. 2	Page A

RECORD OF REVISIONS

Revision

1

2

Section

	Revision Date	Revision Summary
	11/11/16	Initial release of document.
	2/17/20	Added new GTX 345 part numbers and added new helicopter
		models. Corrected formatting errors.

CURRENT REVISION DESCRIPTION

Description

2.4Added GTX 345 NV Panel Mount and GTX 345 NV GPS Panel Mount to Table 2-2 Equipment Weights.

4.2Updated wording and ODA STC Unit Administrator.

4.6Added note to include straps and aluminum foil with measurement during electrical bonding test.

5.2 Updated GTX 3X5 Transponder Alert Flowcharts and added sheet 5. A.3.4 Added EC-135T3 and EC-135P3 models.

190-00734-21	GTX 3X5 Part 27 AML Maintenance Manual
Rev. 2	Page B

INFORMATION SUBJECT TO EXPORT CONTROL LAWS

This document may contain information that is subject to the Export Administration Regulations (EAR) issued by the United States Department of Commerce (15 CFR, Chapter VII, Subchapter C) and may not be exported, released, or disclosed to foreign nationals inside or outside of the United States without first obtaining an export license. A violation of the EAR may be subject to a penalty of up to 10 years imprisonment and a fine of upto $1,000,000 under Section 2410 of the ExportAdministrationActof 1979. Include this notice with any reproduced portion of this document.

Information in this document can change without notice. Go to Garmin’s website flyGarmin.com for updates and supplemental information about the operation of Garmin units.

DEFINITIONS OF WARNINGS, CAUTIONS, AND NOTES

WARNING

A Warning means that injury or death is possible if the instructions are not obeyed.

CAUTION

A Caution means that damage to the equipment is possible.

NOTE

A Note provides more information.

WARNING

This product, its packaging, and its components contain chemicals known to the State of California to cause cancer, birth defects, or reproductive harm. This notice is being provided in accordance with California's Proposition 65. If you have any questions or would like additional information, please refer to our website at www.garmin.com/prop65.

WARNING

Perchlorate Material - special handling may apply.

Refer to www.dtsc.ca.gov./hazardouswaste/perchlorate.

CAUTION

The GTX 335/345 units have a special anti-reflective coated display that is sensitive to waxes and abrasive cleaners. CLEANERS CONTAINING AMMONIA WILL CAUSE DAMAGE TO THE ANTI-REFLECTIVE COATING. Clean the display with a clean, lint-free cloth, with a cleaner that is safe for anti-reflective coatings.

NOTE

Screen shots are intended to provide visual reference only. All information depicted in screen shots, such as software file names, versions, and part numbers, is subject to change and may not be up-to-date.

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TABLE OF CONTENTS

1 INTRODUCTION..............................................................................................................................		1-1
1.1	Content, Scope, and Purpose......................................................................................................	1-2
1.2	Organization...............................................................................................................................	1-3
1.3	Applicability...............................................................................................................................	1-4
1.4	Publications................................................................................................................................	1-4
1.5	Revision and Distribution...........................................................................................................	1-4
1.6	Reference....................................................................................................................................	1-5

2 SYSTEM DESCRIPTION.................................................................................................................		2-1
2.1	GTX 335/335R...........................................................................................................................	2-2
2.2	GTX 345/345R...........................................................................................................................	2-4
2.3	Electrical Load Information.......................................................................................................	2-6
2.4	Weight and Balance ...................................................................................................................	2-7
2.5	Unit Storage................................................................................................................................	2-8

3 GTX CONTROL AND OPERATION.............................................................................................		3-1
3.1	GTX 335/345..............................................................................................................................	3-2
3.2	GTX 335R/345R........................................................................................................................	3-5
3.3	GTX 3X5 Install Tool................................................................................................................	3-6

4 INSTRUCTIONS FOR CONTINUED AIRWORTHINESS.........................................................		4-1
4.1	Applicability...............................................................................................................................	4-2
4.2	Airworthiness Limitations..........................................................................................................	4-3
4.3	Servicing Information ................................................................................................................	4-4
4.4	Maintenance/Inspection Intervals ..............................................................................................	4-5
4.5	Visual Inspection........................................................................................................................	4-6
4.6	Electrical Bonding Test..............................................................................................................	4-9
4.7	Additional Instructions...............................................................................................................	4-9

5 TROUBLESHOOTING ....................................................................................................................		5-1
5.1	GTX General Troubleshooting...................................................................................................	5-2
5.2	GTX Failure Annunciations.......................................................................................................	5-4
5.3	Connector Pinout Information..................................................................................................	5-14

6 UNIT REMOVAL AND RE-INSTALLATION		..............................................................................6-1
6.1	GTX 3X5....................................................................................................................................	6-2
6.2	Transponder Antenna...............................................................................................................	6-17
6.3	Traffic Annunciator (If Installed).............................................................................................	6-17

7	SOFTWARE.......................................................................................................................................			7-1
	7.1	Software Check..........................................................................................................................		7-2
	7.2	GTX 3X5/3X5R Software Update.............................................................................................		7-4
8	SYSTEM CONFIGURATION AND CHECKOUT			.......................................................................8-1
	8.1	Overview....................................................................................................................................		8-2
	8.2	System Checkout........................................................................................................................		8-2
	8.3	Configuration .............................................................................................................................		8-2
	8.4	GTX Test....................................................................................................................................		8-3
9	SYSTEM RETURN TO SERVICE..................................................................................................			9-1
	9.1	Maintenance Records.................................................................................................................		9-1
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Rev. 2				Page ii

APPENDIX A INSTALLATION-SPECIFIC INFORMATION		........................................................A-1
A.1	Rotorcraft-Specific Information................................................................................................	A-2
A.2	Equipment Interfaced to the GTX.............................................................................................	A-4
A.3	GTX 3X5 Airframe-Specific Installation................................................................................	A-11
A.4	GTX 3X5 Configuration Log..................................................................................................	A-28
A.5	GTX 335/335R Configuration Log.........................................................................................	A-29
A.6	GTX 345/345R Configuration Log.........................................................................................	A-30
APPENDIX B ELECTRICAL BONDING PROCEDURES...............................................................		B-1

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LIST OF FIGURES

Figure 2-1 GTX 335 or GTX 335R Interface Summary ........................................................................		2-3
Figure 2-2 GTX 345 or GTX 345R Interface Summary ........................................................................		2-5
Figure 3-1 GTX 335/345 Front Panel ....................................................................................................		3-2
Figure 3-2 GTN 7XX Transponder Control ...........................................................................................		3-5
Figure 3-3 GTN 6XX Transponder Control ...........................................................................................		3-5
Figure 3-4 USB A and USB B Connectors ............................................................................................		3-6
Figure 3-5 GTX 3X5/3X5R State Page ..................................................................................................		3-7
Figure 3-6 GTX 3X5/3X5R Status Page ................................................................................................		3-8
Figure 3-7 GTX 3X5/3X5R Configuration Group .................................................................................		3-9
Figure 3-8 GTX 3X5/3X5R Diagnostics Group ..................................................................................		3-10
Figure 3-9 GTX 3X5/3X5R Product Data Group ................................................................................		3-11
Figure 5-1	GTX Transponder Troubleshooting (All Models) ................................................................	5-3
Figure 5-2	GTX 3X5 Transponder Alerts ..............................................................................................	5-4
Figure 5-3	GTX 3X5 Install Tool Failure/Fault Messages ....................................................................	5-9
Figure 5-4	Rear View, Connector J3251 ..............................................................................................	5-14
Figure 5-5	Rear View, Connector J3252 ..............................................................................................	5-16
Figure 6-1	GTX 3X5 Connector Kits .....................................................................................................	6-2
Figure 6-2	GTX 3X5 without GPS Backplate Assembly .......................................................................	6-3
Figure 6-3	GTX 3X5 with GPS Backplate Assembly ............................................................................	6-4
Figure 6-4	GTX 3X5 Vertical Mount without GPS, Backplate Assembly ............................................	6-5
Figure 6-5	GTX 3X5 Vertical Mount with GPS, Backplate Assembly .................................................	6-6
Figure 6-6	GTX 3X5 Vertical Mount with TNC XPDR Backplate Assembly ......................................	6-7
Figure 6-7	Panel-Mounted GTX 3X5 Transponder .............................................................................	6-10
Figure 6-8	GTX 3X5R Remote Transponder with Horizontal Mount .................................................	6-12
Figure 6-9	GTX 3X5R Remote Transponder with Vertical Mount .....................................................	6-14
Figure 6-10	Garmin Altitude Encoder with Backplate Assembly ..........................................................	6-16
Figure 6-11	Traffic Annunciator Installation .........................................................................................	6-18
Figure 7-1	GTX 3X5 Start-Up Screen ....................................................................................................	7-2
Figure 7-2	GTX 3X5 Product Data Page ...............................................................................................	7-2
Figure 7-3	GTN 6XX/7XX System Page ...............................................................................................	7-3
Figure 7-4	Install Tool Dialog Box ........................................................................................................	7-4
Figure 7-5	GTX 3X5 Install Tool Software Upload Page ......................................................................	7-5
Figure A-1	Rotorcraft-Specific Information ..........................................................................................	A-2
Figure A-2	Interfaced Equipment Table ................................................................................................	A-5
Figure B-1	Aluminum Tape Joint ..........................................................................................................	B-2

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LIST OF TABLES

Table 1-1	Reference Documentation ....................................................................................................	1-4
Table 2-1 GTX Electrical Load .............................................................................................................		2-6
Table 2-2	Equipment Weights ..............................................................................................................	2-7
Table 4-1	Maintenance/Inspection Intervals .........................................................................................	4-5
Table 5-1	J3251 Pinout .......................................................................................................................	5-14
Table 5-2	J3252 Pinout .......................................................................................................................	5-16
Table 5-3	GTX 3X5/3X5R Encoded Altitude Pin Assignments ........................................................	5-17
Table 5-4	GTX 3X5/3X5R Discrete Outputs ......................................................................................	5-18
Table 5-5	GTX 3X5/3X5R Configurable Output Pins .......................................................................	5-18
Table 5-6	GTX 3X5/3X5R Discrete Inputs ........................................................................................	5-19
Table 5-7	GTX 3X5/3X5R Configurable Input Pins ..........................................................................	5-19
Table 5-8	GTX 3X5/3X5R RS-232 Connections ...............................................................................	5-20
Table 5-9	GTX 3X5/3X5R ARINC 429 Connections ........................................................................	5-20
Table 5-10	GTX 3X5/3X5R RS-422 Connections ...............................................................................	5-20
Table 5-11	GTX 345/345R HSDB Connections ...................................................................................	5-21
Table 6-1	GTX 3X5 Connector Kit ......................................................................................................	6-2
Table 6-2	Standard Mount Backplate (P/N 011-02976-00 and -01) .....................................................	6-3
Table 6-3	Vertical Mount Backplate (P/N 011-02976-10) ...................................................................	6-5
Table 6-4	Vertical Mount Backplate (P/N 011-02976-11) ...................................................................	6-6
Table 6-5	Vertical Mount Backplate (P/N 011-02976-12) ...................................................................	6-7
Table 6-6	GTX 3X5 Transponder Parts List .........................................................................................	6-9
Table 6-7	Garmin Altitude Encoder Kit (P/N 011-03080-00) ............................................................	6-16
Table 6-8	Traffic Annunciator Installation .........................................................................................	6-18

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1	INTRODUCTION
1.1	Content, Scope, and Purpose ............................................................................................................		1-2
1.2	Organization......................................................................................................................................		1-3
1.3	Applicability .....................................................................................................................................		1-4
1.4	Publications.......................................................................................................................................		1-4
1.5	Revision and Distribution.................................................................................................................		1-4
1.6	Reference..........................................................................................................................................		1-5
1.6.1		Terminology...............................................................................................................................	1-5
1.6.2		Acronyms...................................................................................................................................	1-5

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1.1 Content, Scope, and Purpose

ThisdocumentprovidesInstructionsfor ContinuedAirworthiness(ICA) of theGTX 3X5withADS-B functionality installedandcomplianttoADS-B OutVersion2 underAMLSTC SR02124SE.Thisdocument satisfiesthe requirementsforcontinued airworthinessasdefinedby14CFR Part27.1529and14 CFR Part27 AppendixA. Informationinthisdocumentisrequiredto maintainthecontinuedairworthinessof the GTX3X5.

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1.2 Organization

The following outline briefly describes the organization of this manual:

Section 2: System Overview

Equipment features

Electrical load information

Weight and balance

Section 3: Control and Operation

Controlling the GTX

Using the GTX 3X5 Install Tool

Section 4: Instructions for Continued Airworthiness

Applicability

Airworthiness limitations

Service information

Maintenance intervals

Bonding test

Section 5: Troubleshooting

General troubleshooting

Failure annunciations

Connector pinout information

Section 6: Unit Removal and Re-Installation

Removal and re-installation of the GTX

Removal and re-installation of the GarminAltitude Encoder

Removal and re-installation of the transponder antenna

Removal and re-installation of the traffic annunciator (if installed)

Section 7: Software

Software check

Software update

Section 8: System Configuration and Checkout

System checkout

Configuration

GTX tests

Section 9: System Return to Service Procedure

Maintenance records

Appendix A: Rotorcraft-Specific Information

Rotorcraft-specific information form

Equipment interfaced to the GTX

Wire routing

Configuration logs

Appendix B: Special Bonding Procedures

Surface preparation

Aluminum tape repair and replacement considerations

190-00734-21	GTX 3X5 Part 27 AML Maintenance Manual
Rev. 2	Page 1-3

1.3 Applicability

This document applies to all rotorcraft with the GTX 3X5 installed in accordance with STC SR02124SE. Modification of a rotorcraft by this Supplemental Type Certificate (STC) obligates the rotorcraft operator to implement the specific maintenance practices and/or airworthiness limitations provided in this document. This is in addition to the rotorcraft’s existing approved maintenance, inspection, and airworthiness limitations programs.

1.4 Publications

In addition to this manual, the following documents are recommended to perform maintenance based on the installed and interfaced equipment. It is the responsibility of the owner/operator to ensure the latest applicable versions of these documents are used during operation, servicing, or maintenance of the rotorcraft.

Table 1-1 Reference Documentation

Document	Garmin P/N	Applicable Sections
GTX 3X5 Part 27 AML STC Equipment List	005-00734-A5	All
GTN 625/635/650 Pilot’s Guide	190-01004-03	2.1 and 15.3.2
GTN 725/750 Pilot’s Guide	190-01007-03	2.1 and 16.3.2

1.5 Revision and Distribution

This document is required for maintaining the continued airworthiness of the rotorcraft. Garmin Dealers may obtain the latest revision of this document at the Garmin Dealer Resource Center website.

Dealers are notified of manual revision changes by way of a Garmin Service Bulletin.

Owner and operators may obtain the latest revision of this document at flyGarmin.com or by contacting a Garmin dealer. Garmin contact information is available at flyGarmin.com.

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1.6 Reference

1.6.1Terminology

Except where specifically noted, references made to the GTX 3X5 will apply to the GTX 335/335R/345/ 345R.ADS-B orADS-B Out refers to Version 2ADS-B Out only. ADS-B In refers to TIS-B traffic and FIS-B weather received from ground stations over UAT, as well asADS-B andADS-R traffic targets received directly over 1090 MHz or UAT.

Throughout this document, references will be made to metallic rotorcraft. For the purposes of this manual, metallic rotorcraft will be those with an aluminum skin. Nonmetallic rotorcraft refers to all other rotorcraft (e.g., rotorcraft with composite skin).

Unless otherwise stated, all units of measure are in US standard units.

The term squitter refers to a burst or broadcast of data that is transmitted periodically by a Mode S transponder without interrogation.

1.6.2 Acronyms
AC: Advisory Circular	HAT: HeightAbove Terrain
ADC: Air Data Computer	ICA: Instructions for ContinuedAirworthiness
ADS-B: Automatic Dependent Surveillance -	ICAO: International CivilAviation Organization
Broadcast
AHRS: Attitude Heading Reference System	I/O: Input/Output
AML: Approved Model List	MFD: Multifunction Display
ATC: Air Traffic Control	PED: Portable Electronic Device
ATCRBS: Air Traffic Control Radar Beacon System	SBAS: Satellite-BasedAugmentation System
EGNOS: European Geostationary Navigation	SPI: Special Position Identifier
Overlay Service
ES: Extended Squitter	SRM: Structural Repair Manual
FAA: FederalAviationAdministration	STC: Supplemental Type Certificate
FIS-B: Flight Information System-Broadcast	TAS: TrafficAdvisory System
GAE: GarminAltitude Encoder	TCAS: TrafficAlert and CollisionAvoidance
	System
GNS: Garmin Navigation System	TIS: Traffic Information Service
GNSS: Global Navigation Satellite System	TSO: Technical Standard Order
GPS: Global Positioning System	UAT: UniversalAccess Transceiver
GTN: Garmin Touchscreen Navigator	VSWR: Voltage Standing Wave Ratio
GTX: Garmin Transponder	WAAS: Wide AreaAugmentation System

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2	SYSTEM DESCRIPTION
2.1	GTX 335/335R .................................................................................................................................	2-2
2.2	GTX 345/345R .................................................................................................................................	2-4
2.3	Electrical Load Information..............................................................................................................	2-6
2.4	Weight and Balance..........................................................................................................................	2-7
2.5	Unit Storage......................................................................................................................................	2-8

Garmin GTX 3X5 units operate on radar frequencies receiving ground radar or TCAS interrogations. The GTX transmits a coded response of pulses to ground-based radar on a frequency of 1090 MHz. Each unit has IDENT capability and replies to ATCRBS Mode A, Mode C, and Mode S All-Call interrogation. GTX 345/345R units include ADS-B In, which provides TIS-B and FIS-B data via UAT and 1090 MHz. GTX 3X5 units offer an optional Garmin Altitude Encoder to meet the required barometric pressure altitude source and an optional internal GPS/SBAS source to meet the required GNSS position source integrity for ADS-B Out.

The Garmin transponders approved by this STC are the family of GTX 3X5 transponders.

GTX 3X5 units all provideADS-B Out functionality. GTX 345/345R units provide ADS-B In. GTX 3X5 models include:

GTX 335

GTX 345

GTX 335R

GTX 345R

Automatic Dependent Surveillance-Broadcast (ADS-B) technology improves situational awareness and flight safety.AGarmin transponder withADS-B capabilities will automatically transmit position, velocity, and heading information to other aircraft and ground stations. The current air traffic control system depends on a transponder request for pertinent aircraft information; whereasADS-B provides automatic transmission of aircraft information without a request.

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2.1 GTX 335/335R

GTX 335/335R units are panel or remote-mounted units that have Mode S withADS-B Out extended squitter capability. The panel-mounted unit contains an integrated display, while the remote-mounted unit requires an interface to a control source for normal operation and functionality.

GTX 335/335R units have these features:

Mode S transponder

ADS-B Out capability

Optional internal GNSS receiver

Optional GAE pressure sensor module

Entry of squawk code and flight ID

Show squawk code and flight ID

Show pressure altitude

Show outside air temp

Show density altitude

Show flight timers

Audio output

TIS-Atraffic output to a compatible display

The transponder provides anADS-B Out failure message to alert the crew that the unit has a degraded ADS-B system.

GTX 335/335R units interface through these:

ARINC 429

RS-232

Gray code

Discrete I/O

Figure 2-1 provides a summary of the interfaces provided for the GTX 335 or GTX 335R. For interfaces approved by this STC, refer to GTX 3X5 Part 27 AML STC Installation Manual.

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Optional Interfaces

Audio Panel

Heading Source

Traffic System

For XPDR cross-talk

Secondary GPS

Temperature

External Ident

External Standby

Air Data Source

Required Interfaces

Bottom Antenna

GTX 335/335R

Power/Ground

	GTX 335R	Control
		Collective Switch
	Required if HAT is	OR
	Not Available
		Radar Altitude
		Source

	Legend
New LRU	Existing LRU

	Figure 2-1 GTX 335 or GTX 335R Interface Summary
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2.2 GTX 345/345R

GTX 345/345R units are panel or remote-mounted units that supply Mode S withADS-B Out extended squitter and UAT and 1090 receivers forADS-B In capabilities. The panel-mounted unit has an integrated display, while the remote-mounted unit requires an interface to a control source for normal operation and functionality.

GTX 345/345R units have these features:

Mode S transponder

ADS-B Out capability

ADS-B In capability with built-in 1090 MHz and UAT receivers

Optional internal GNSS receiver

Optional GAE pressure sensor module

Entry of squawk code and flight ID

Show squawk code and flight ID

Show pressure altitude

Show outside air temp

Show density altitude

Show flight timers

Audio output

Bluetooth interface to show weather and traffic on portable devices

The transponder provides anADS-B failure message to alert the crew that the unit has a degradedADS-B (In or Out) system.

GTX 345/345R units interface through these:

HSDB

ARINC 429

RS-232

RS-422

Gray code

Discrete I/O

Figure 2-2 provides a summary of the interfaces provided for the GTX 345 or GTX 345R. For interfaces approved by this STC, refer to GTX 3X5 Part 27 AML STC Installation Manual.

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Optional Interfaces

Audio Panel

Heading Source

Secondary GPS

Temperature

External Ident

External Standby

Air Data Source

External Traffic	For NO display Install
Annunciator

Required Interfaces

Bottom Antenna

GTX 345/345R

Power/Ground

	GTX 345R	Control
		Collective Switch
	Required if HAT is	OR
	Not Available
		Radar Altitude
		Source

	Legend
New LRU	Existing LRU

	Figure 2-2 GTX 345 or GTX 345R Interface Summary
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2.3 Electrical Load Information

Table 2-1 contains electrical load information for the GTX. Circuit protection for the GTX is located within the rotorcraft’s avionics circuit protection and is labeled “XPDR.” AppendixA contains details specific to the load changes for the installation.

Unit

GTX 335

GTX 335, GPS

GTX 345

GTX 345, GPS

GTX 335/345, GPS

Table 2-1 GTX Electrical Load

	Characteristic	Specification
		14 VDC	28 VDC
	Input current, typical	0.57 A	0.29 A
	Input current, maximum	0.86 A	0.43 A
	Input current, typical	0.72 A	0.36 A
	Input current, maximum	1.22 A	0.61 A
	Input current, typical	0.72 A	0.36 A
	Input current, maximum	1.30 A	0.65 A
	Input current, typical	1.07 A	0.54 A
	Input current, maximum	1.43 A	0.72 A
	Input current, GPS KEEP ALIVE	65 µA typical	20 µA typical
		85 µA maximum	40 µA maximum

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2.4 Weight and Balance

Update the rotorcraft Equipment List to indicate any items that are added, removed, or relocated. Each change must include the date and the name and certificate number of the person making the entry. Table 2-2 contains equipment weights.

Table 2-2 Equipment Weights

Kit P/N		Description	Weight
			(lbs/kg)
010-01214-01	GTX 335 Panel Mount		2.8 / 1.27
010-01214-21	GTX 335 NV Panel Mount		2.8 / 1.27
010-01214-41	GTX 335 GPS Panel Mount		2.9 / 1.32
010-01216-01	GTX 345 Panel Mount		3.1 / 1.41
010-01216-41	GTX 345 GPS Panel Mount		3.2 / 1.45
010-01216-21	GTX 345 NV Panel Mount		3.1 / 1.41
010-01216-61	GTX 345 NV GPS Panel Mount		3.2 / 1.45
010-01215-01	GTX 335	Remote	2.5 / 1.13
010-01217-01	GTX 345	Remote	2.9 / 1.32
010-01215-41	GTX 335	GPS Remote	2.7 / 1.22
010-01217-41	GTX 345	GPS Remote	3.0 / 1.36

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2.5 Unit Storage

The GTX 3X5 transponder unit is qualified for an operating temperature range of -55 ºC to +85 ºC. Recommended unit storage temperatures (uninstalled) are between 10 ºC and 35 ºC.

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3 GTX CONTROL AND OPERATION

3.1	GTX 335/345....................................................................................................................................		3-2
3.2	GTX 335R/345R...............................................................................................................................		3-5
3.3	GTX 3X5 Install Tool.......................................................................................................................		3-6
3.3.1		State Page...................................................................................................................................	3-7
3.3.2		Status Page .................................................................................................................................	3-8
3.3.3		Configuration Group..................................................................................................................	3-9
3.3.4		Diagnostics Group....................................................................................................................	3-10
3.3.5		Product Data Group..................................................................................................................	3-11
3.3.6		Software Upload Group ...........................................................................................................	3-11

Control and operation of GTX 335/345 units occurs through the front panel of the GTX. Control and operation of remote-mounted GTX 335R/345Runits is handled through the external interface provided via the GTN 6XX/7XX. ADS-B In information from the GTX 345 can be displayed through the external interface providedvia the GTN 6XX/7XX or GNS 400W/500Wseries. Figure 3-2 and Figure 3-3 show the transponder control pages.

Important Codes

NOTE

The selected identification code must be entered carefully (either the one assigned by air traffic control for IFR flight or an applicable VFR transponder code).

1200 VFR code for any altitude in the US (refer to ICAO standards) 7000 VFR code commonly used in Europe (refer to ICAO standards) 7500 Hijack code (rotorcraft is subject to unlawful interference)

7600 Loss of communications

7700 Emergency

Avoid selecting code 7500 and all codes in the 7600-7777 range. These codes trigger special emergency alerts inATC monitoring facilities. Arotorcraft’s transponder code is used forATC tracking purposes; therefore, be careful when making routine code changes.

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3.1 GTX 335/345

Figure 3-1 GTX 335/345 Front Panel

Function Selection Keys

NOTE

If the transponder is in the ON or ALT operating mode, the transponder becomes an active part of the Air Traffic Control Radar Beacon System (ATCRBS). The transponder responds to interrogations from TCAS-equipped rotorcraft.

The function selection keys are: OFF Powers off the GTX 3X5.

STBY Selects the Standby mode. Pressing the STBY key when the GTX 335/345 is powered off automatically powers the unit on in Standby mode. When in Standby mode, the transponder does not reply to interrogations (but new codes can be entered) and a “SBY” indication appears on the display.

ON Selects the On mode, which generates Mode A and Mode S replies, but Mode C altitude reporting is inhibited. Pressing the ON key when the GTX 335/345 is powered off automatically powers on the unit in Mode A and will transmit a squawk code when interrogated. ADS-B Out will not return barometric altitude as it switches to GPS altitude in this mode. Interrogations are indicated by the reply symbol (®). The replies do not include altitude information.

ALT Altitude mode is automatically selected when the rotorcraft becomes airborne using the unit’s Air/Ground logic or when the ALT key is pressed. Pressing the ALT key when the

GTX 335/345 is powered off automatically powers on the unit in Altitude Reporting mode. While the rotorcraft is on the ground and inALT mode, the transponder does not allow ModeAand Mode C replies, but it does permit acquisition squitter and replies to Mode S interrogations.

While the rotorcraft is inALT mode and airborne, it will generate Mode A, Mode C, and Mode S replies, as well as transmit acquisition and extended squitter, includingADS-B Out.

All transponder interrogations are indicated by the reply symbol (®).

IDENT Pressing the IDENT key activates the Special Position Identification (SPI) pulse for

18 seconds, identifying the transponder return from others on an air traffic controller’s screen. During the IDENT period, the word “IDENT” appears in the upper-left corner of the display.

VFR Sets the transponder code to the pre-programmed VFR code selected in Configuration mode (set to 1200 at the factory). Pressing the VFR key again restores the previous identification code.

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FUNC In Normal mode, pressing the FUNC key changes the subpage group shown on the right side of the display. Subpages include Flight ID, PressureAltitude, Flight Time,Altitude Monitor, System Count Up, and Count Down Timers. In Configuration mode, it steps through the function pages.

ENT Confirms entry for selected item and moves the cursor to the next editable item, or function selection, in configuration and normal operation. Starts and stops the altitude monitor, count up, count down, and flight timers.

CRSR Selects changeable fields in configuration and normal operation. Initiates entry of the starting time for the count down timer and cancels transponder code entry. Holding the CRSR key during power-up will place the unit into a Ground Test mode that forces the rotorcraft into an airborne status for testing purposes.

CLR Resets the count up, count down, and flighttimers. Cancels the previous key press duringcode selection, count down entry, or flight ID entry. Used in Configuration mode to scroll through the function pages.

8Used as a scroll-up key to navigate through page groups in Normal and Configuration mode.

9Used as a scroll-down key to navigate through page groups in Normal and Configuration mode.

Code Selection

Code selection is entered with eight keys (0 through 7) providing 4,096 active identification codes. Pushing one of these keys begins the code selection sequence. The new code is not activated until the fourth digit is entered. Pressing the CLR key moves the cursor back to the previous digit. Pressing the CLR key when the cursor is on the first digit of the code, or pressing the CRSR key during code entry, removes the cursor and cancels data entry, restoring the previous code. The numbers 8 and 9 are not used for code entry, only for flight ID entry, count down time, rotorcraft tail number entry, and data selection in Configuration and Normal mode.

Configuration Mode

To enter Configuration mode, press and hold the ENT key, then energize the unit. To exit Configuration mode, press and hold the OFF key until the unit de-energizes.

To cycle through the pages, press the FUNC key

To access items on the page, press the CRSR key

To cycle through the selections of an item on the page, press the 8 or 9 key

To scroll up or down on the page when nothing is selected, press the 8 or 9 key

To move within the page, press the ENT key

To move to previous selection on the page, press the CLR key

To exit the page, press the FUNC key

GTX 3X5 units may also be configured using the GTX 3X5 Install Tool. For configuration using the GTX 3X5 Install Tool, refer to Section 3.3.

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Function Display

FLIGHT ID IfAllow Pilot to Edit Flt ID is configured to YES, the flightID can be changed by the pilot at any time in Normal mode. This allows the pilot/crew to enter the specific flight ID for transmission toATC interrogations.

UP COUNTER Timer controlled by ENT and CLR keys.

DOWN COUNTER Timercontrolledby ENT,CLR, andCRSRkeys.The initialcountdowntime is entered with the 0 through 9 keys.

FLIGHTTIMER Displays the flight time, controlled by the ENT key or by one of four airborne sources (squat switch, GPS ground speed recognition, air data airspeed recognition, or altitude increase), as configured during installation. The timer begins when the GTX 3X5 determines that the rotorcraft is airborne.

TRIPTIMER Timer controlled by ENT and CLR keys.

PRESSUREALT Displays the altitude data supplied to the GTX 3X5 in feet, hundreds of feet (flight level), or meters, depending on configuration.

ALT MONITOR Controlled by ENT key.Activates a voice alarm and warning annunciator when altitude limit is exceeded.

SAT/DALT Displayed when the GTX 3X5 is configured with temperature input. Displays StaticAir Temperature and DensityAltitude.

CONTRAST/OFFSET Contrast is controlled by the 8 and 9 keys.

BACKLIGHT/OFFSET This page is only displayed if photocell backlighting mode is selected in Configuration mode. Backlighting is controlled by the 8 and 9 keys.

MESSAGES Alerts crew of transponder faults, fails, and advisory messages. “MSG” appears when a message is generated. CRSR and ENT keys access messages for acknowledgment and viewing.

BLUETOOTH This page is only shown on the GTX 345 when configured for Bluetooth at installation. When selected, it allows PEDs to pair to the GTX 345 and device management to showADS-B In data.

INTERNAL GPS This page displays Lat/Long accuracy, number of connected satellites, horizontal figure of merit, whether the unit is using internal GPS, and overall status.

1090ESTX CTRL This is only displayed when the unit is configured for 1090ES Out Control in Configuration mode to be Pilot Set. Once configured, this can be highlighted by the CRSR key, changed by the 8 and 9 keys, and selected by ENT key.

Turns the extended squitter function on or off.

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3.2 GTX 335R/345R

Figure 3-2 and Figure 3-3 show the GTX control pages associated with the GTN 6XX/7XX. Refer to the specific pilot’s guide and cockpit reference guide for details regarding control and function. Part numbers for these documents are listed in Table 1-1.

Figure 3-2 GTN 7XX Transponder Control

Figure 3-3 GTN 6XX Transponder Control

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3.3 GTX 3X5 Install Tool

NOTE

If the GTX 3X5/3X5R is configured to interface with a display control unit, the display control unit must be turned off or in Configuration mode prior to running the GTX 3X5 Install Tool.

NOTE

The GTX 3X5 Install Tool pages shown within this manual reflect GTX 3X5 Install Tool version 2.05. Some differences in operation may be observed when comparing information in this manual to later versions of the install tool.

The GTX 3X5 Install Tool is available for download from the Garmin Dealer Resource Center. The GTX 3X5 Install Tool requires a computer with available USB 2.0 ports and Microsoft Windows XP or later.

AUSB A-to-B cable is required to interface between a computer and the GTX 3X5/3X5R. For additional details, refer to Figure 3-4. To use the GTX 3X5 Install Tool:

1.Remove power from the GTX 3X5/3X5R.

2.Remove power from the display control unit or verify it is in Configuration mode.

3.Connect the USB cable between the GTX 3X5 and the computer.

4.Energize the GTX 3X5/3X5R and run the GTX 3X5 Install Tool.

86%$ 86% %

Figure 3-4 USB A and USB B Connectors

The install tool is used to check equipment status, load software, and configure the unit. To place a GTX 3X5/3X5R unit in Configuration mode:

1.In the Unit Mode window, change “Normal Mode” to “Configuration Mode.”

2.Click the Set key.

Green boxes indicate a function operating correctly. Red boxes indicate a failure. Yellow boxes indicate a fault or warning. Gray boxes indicate the presence of a message.

The bottom of the install tool displays unit information, such as software version, connection status, and unit mode. The tool will annunciate if alerts, faults, failures, or warnings exist. The menu bar at the top of the install tool has a GTX key and a Help key. The GTX key provides the following options:

•Save configuration

•Load configuration

•Reset configuration

•Push configuration from install tool to configuration module

•Exit

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The Help key provides the following information:

•Part number

•Version number

•Copyright statement

•Software license agreements

3.3.1State Page

The State page of the GTX 3X5 Install Tool reports the current mode of the GTX 3X5/3X5R, Flight ID, Squawk Code, and PressureAltitude. Mode selections include Ground Test and Traffic Test modes. Standby and Operate test modes are also provided for TCAS.

Figure 3-5 GTX 3X5/3X5R State Page

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3.3.2Status Page

The Status page reports failures, faults, warnings, and pilot alerts. Information such as whether there is a configuration module present is also displayed.

Figure 3-6 GTX 3X5/3X5R Status Page

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3.3.3Configuration Group

The Configuration group contains the following pages:

Aircraft page – allows the configuration of basic aircraft configuration and flight ID settings

Airframe page – allows the configuration of basic airframe configuration and operational options settings

Unit page – allows the configuration of identification code, unit options, and display options

Interfaces page – allows the configuration of serial, A429, discretes, and HSDB settings

Sensors page – allows the configuration of GarminAltitude Encoder, GPS, internalAHRS, and additional sensors

Audio page – allows the configuration of audio options and alerts

Display page – allows the configuration of display and key backlight, photocell and lighting bus curves, and default offsets

NOTE

All configurable settings must match the GTX System Configuration Log retained in the rotorcraft permanent records.

Figure 3-7 GTX 3X5/3X5R Configuration Group

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