Table Of Contents - Garmin GMA 340 Series Maintenance Manual

Table of Contents

Table Of Contents3
Description And Operation7
Introduction7
General Description7
Theory Of Operation8
Power Input Board Assembly8
Main Board Assembly8
Front Panel Board Assembly8
Special Test Equipment9
Gma 340 Rear Connectors9
Gma 340 Test Panel9
Test Panel Parts List10
Typical Test Panel Layout11
Test Points11
Construction Notes12
Test Harness, J1 And 52 Pin Assignments12
Test Panel Schematic Diagram (Sheet 2)15
Audio Coax Cable Assembly18
Troubleshooting19
Front Panel Rear View, Connector J1 And 52 Location20
Front Panel Connector Detail (Dual Adf In Parentheses)20
Main Board Component Location21
Main Board Connector Detail21
Power Input Board22
Power Input Board Connector Detail22
Power On Check23
28V Lighting23
14V Lighting23
Ptt Annunciator Check23
Annunciator Failure24
Front Panel Controls24
Disassembly And Reassembly25
Tools Required25
Disassembling The Unit25
Removing Top And Bottom Covers25
Flexible Circuit Cable26
Power-Input Board Assembly26
Front Panel Assembly26
Marker Beacon Lamp Rack Assembly26
Installation Screw Shaft Assembly29
Installing Top And Bottom Covers29
Testing31
General31
Adjustment/Measurement Accuracy31
Test Equipment Precautions31
Required Test Equipment32
Test Panel32
Bench Testing32
Test Equipment Setup32
Gma 340 Test Connections33
Hp-8920B Default Settings34
Test Panel Default Settings35
Standard Test Signals35
Input Voltages35
Main Power35
Microphone Input Signal36
Marker Beacon Input Signal36
Power Off Check36
Panel Lighting36
28 V Lighting37
14 V Lighting37
Loaded Microphone Voltage Inputs37
Pilot Ptt Tests37
Masq Inhibit39
Audio Communication Check39
Headset Outputs39
Audio Gain39
Speaker Outputs40
Audio Frequency Response40
Microphone Gain40
Crew Microphone Frequency Response40
Ics Microphone Frequency Response41
Microphone Gain (Ics)41
Pilot Microphone41
Copilot Microphone41
Microphone (Pa) Gain42
Squelch Characteristics42
Auxiliary Entertainment (Music) Inputs42
Music Frequency Response (Music 2 Not Available On 340 Dual Adp)43
Music Mute Operation43
Marker Beacon43
Receiver Threshold43
High Sensitivity Test44
Outer Marker (400 Hz)44
Middle Marker (1300 Hz)44
Airwayslnner Marker (3000 Hz)44
External Marker Lamp Outputs45
Middle Marker Sense45
Marker Mute45
Isolation Mode Operational Checks45
Replaceable Assemblies47
List Of Replaceable Parts47
Assembly Drawings49
Gma 340 Front Panel Assembly49
Marker Lamp Rack Assembly, Front And Rear Detail49
Gma 340 Final Assembly50