00-25-234.PDF

TO 00-25-234

TECHNICAL MANUAL

GENERAL SHOP PRACTICE REQUIREMENTS

FOR THE REPAIR, MAINTENANCE, AND

TEST OF ELECTRICAL EQUIPMENT

DISTRIBUTION STATEMENT A - Approved for public release; distribution is unlimited. PA Case Number 04-10-83. Other requests for this document shall be referred to AFLCMC/LZPTP, Robins AFB, GA 31098. Questions concerning technical content shall be referred to AFLCMC/

EZSS.

Published Under Authority of the Secretary of the Air Force

22 SEPTEMBER 2013 CHANGE 12 - 27 OCTOBER 2021

BASIC AND ALL UPDATES HAVE BEEN MERGED TO MAKE THIS A COMPLETE PUBLICATION.

Dates of issue for original and changed pages are:

Original. . . . . . . .0 . . .22 September 2013 Change . . . . . . . . 1. . . . . .23 March 2014 Change . . . . . . . . 2 . . . . . . . 19 May 2016 Change . . . . . . . . 3 . . . . . . . 14 July 2016 Change . . . . . . . . 4 . . . 27 November 2016 Change . . . . . . . . 5 . . . . . . 8 March 2017 Change . . . . . . . . 6 . . . . . . . 24 May 2017

Change . . . . . . . . 7. . . . . .25 March 2018 Change . . . . . . . . 8 . . . . . . 9 March 2019 Change . . . . . . . . 9 . . . . . . . 14 June 2019 Change . . . . . . . 10. . . . . .9 January 2020 Change . . . . . . . 11. . . . . .5 January 2021 Change . . . . . . . 12. . . . .27 October 2021

TOTAL NUMBER OF PAGES IN THIS PUBLICATION IS 226, CONSISTING OF THE FOLLOWING:

Page *Change No. No.

Page *Change No. No.

Page *Change No. No.

Title A i ii iii iv v vi vii viii Blank ix - x xi - xiii xiv Blank xv - xvi Deleted 1-1 - 1-6 2-1 - 2-5 2-6 Blank 3-1 3-2 Blank 4-1 - 4-48 4-49 4-50 - 4-53 4-54 - 4-56 4-56.1 Added 4-56.2 Blank 4-57 - 4-67 4-68 5-1 5-2 Blank 6-1 - 6-18 7-1 - 7-2 7-3 7-4 7-5 7-6 - 7-8 7-8.1 Added 7-8.2 Blank 7-9 7-10 - 7-11 7-12

7-13 7-14 7-15 - 7-16 7-16.1 - 7-16.2 Deleted 7-17 - 7-18 7-18.1 Added 7-18.2 Blank 7-19 - 7-20 7-20.1 - 7-20.2 Added 7-21 7-22 7-23 - 7-24 7-25 7-26 7-26.1 Added 7-26.2 Blank 7-27 - 7-28 7-28.1 - 7-28.4 Added 7-29 - 7-31 7-32 - 7-33 7-34 7-34.1 7-34.2 Blank 7-35 - 7-43 7-44 - 7-46 7-46.1 Added 7-46.2 Blank 7-47 - 7-49 7-50 - 7-51 7-52 - 7-54 7-55 - 7-58 Added 8-1 - 8-14 9-1 9-2 Blank 10-1 10-2 Blank Glossary 1 - Glossary 8 Index 1 - Index 5 Index 6 Blank

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LIST OF EFFECTIVE PAGES

INSERT LATEST CHANGED PAGES. DESTROY SUPERSEDED PAGES.

NOTE The portion of the text affected by the changes is indicated by a vertical line in the outer margins of the page. Changes to illustrations are indicated by shaded or screened areas, or by miniature pointing hands.

* Zero in this column indicates an original page.

A Change 12 USAF

TABLE OF CONTENTS

Chapter Page

LIST OF ILLUSTRATIONS . . . . . . . . . . . . . vi

LIST OF TABLES . . . . . . . . . . . . . . . . . . . . vii

INTRODUCTION . . . . . . . . . . . . . . . . . . . . ix

SAFETY SUMMARY . . . . . . . . . . . . . . . . . xi

1 INTRODUCTION . . . . . . . . . . . . . . . . . . . 1-1

1.1 MATERIALS AND PARTS . . . . . . 1-1

1.2 PARTS SUBSTITUTION . . . . . . . 1-1

1.3 ECONOMICAL REPAIR . . . . . . . 1-1

1.4 RECOMMENDED TOOLS . . . . . . 1-1

2 WORKMANSHIP . . . . . . . . . . . . . . . . . . . 2-1

2.1 GENERAL . . . . . . . . . . . . . . . . . 2-1

2.2 WIRING. . . . . . . . . . . . . . . . . . . 2-1

2.3 THERMAL BONDING. . . . . . . . . 2-1

2.4 MECHANICAL BONDING. . . . . . 2-1

2.5 INSULATING . . . . . . . . . . . . . . . 2-1

2.6 REPAIR AND REFINISHING . . . . 2-1

2.7 MARKING . . . . . . . . . . . . . . . . . 2-1

2.8 CLEANING . . . . . . . . . . . . . . . . 2-1

2.9 HANDLING AND STORAGE . . . . 2-2

2.9.1 Protective Measures for Electrical

Connectors . . . . . . . . . . . . . . . 2-2

2.9.2 Preparation for Shipment and

Storage . . . . . . . . . . . . . . . . . . 2-2

2.9.3 Handling. . . . . . . . . . . . . . . . . . . 2-3

2.10 INSPECTION . . . . . . . . . . . . . . . 2-5

3 SOLDERING. . . . . . . . . . . . . . . . . . . . . . . 3-1

3.1 GENERAL . . . . . . . . . . . . . . . . . 3-1

4 GENERAL REPAIR . . . . . . . . . . . . . . . . . . 4-1

4.1 GENERAL . . . . . . . . . . . . . . . . . 4-1

4.2 SAFETY. . . . . . . . . . . . . . . . . . . 4-1

4.2.1 Work Area . . . . . . . . . . . . . . . . . 4-1

4.2.2 Rotating Machinery . . . . . . . . . . . 4-1

4.2.3 Chemicals . . . . . . . . . . . . . . . . . . 4-1

4.2.4 Electronics . . . . . . . . . . . . . . . . . 4-3

4.2.5 Power Extension Cables . . . . . . . . 4-3

4.3 EQUIPMENT CASES AND

PANELS. . . . . . . . . . . . . . . . . 4-3

4.3.1 Dents and Chips. . . . . . . . . . . . . . 4-3

4.3.2 Cracks and Holes . . . . . . . . . . . . . 4-3

Chapter Page

4.3.3 Connectors . . . . . . . . . . . . . . . . . 4-3

4.4 EQUIPMENT

PERFORMANCE. . . . . . . . . . . 4-4

4.4.1 Deviations. . . . . . . . . . . . . . . . . . 4-4

4.4.2 Vibration Testing . . . . . . . . . . . . . 4-4

4.4.3 Shock Testing . . . . . . . . . . . . . . . 4-4

4.5 MECHANICAL

FABRICATION . . . . . . . . . . . . 4-4

4.5.1 Chassis Construction. . . . . . . . . . . 4-4

4.5.2 Pins . . . . . . . . . . . . . . . . . . . . . . 4-5

4.5.3 Rivets. . . . . . . . . . . . . . . . . . . . . 4-6

4.5.4 Eyelets . . . . . . . . . . . . . . . . . . . . 4-7

4.5.5 Studs . . . . . . . . . . . . . . . . . . . . . 4-7

4.5.6 Retaining Rings . . . . . . . . . . . . . . 4-7

4.5.7 Threaded Fasteners . . . . . . . . . . . . 4-8

4.6 SAFETY WIRING AND SAFETY

CABLING . . . . . . . . . . . . . . . 4-11

4.6.1 Material . . . . . . . . . . . . . . . . . . . 4-11

4.6.2 Twists Per Inch . . . . . . . . . . . . . . 4-11

4.6.3 Double Twist Method . . . . . . . . . . 4-11

4.6.4 Single Wire Method . . . . . . . . . . . 4-11

4.6.5 Twisting With Pliers . . . . . . . . . . . 4-12

4.6.6 Twisting With Special Tools. . . . . . 4-12

4.6.7 Tightness of Wire . . . . . . . . . . . . . 4-12

4.6.8 AN Connectors . . . . . . . . . . . . . . 4-12

4.6.9 Split-Shell Assemblies. . . . . . . . . . 4-14

4.6.10 Solid-Shell Angle Plugs. . . . . . . . . 4-14

4.6.11 V-Band Couplings . . . . . . . . . . . . 4-14

4.7 CLAMPS . . . . . . . . . . . . . . . . . . 4-16

4.8 WELDING . . . . . . . . . . . . . . . . . 4-18

4.9 WIRING. . . . . . . . . . . . . . . . . . . 4-18

4.9.1 Type of Wire . . . . . . . . . . . . . . . . 4-18

4.9.2 Protection . . . . . . . . . . . . . . . . . . 4-18

4.9.3 Marking . . . . . . . . . . . . . . . . . . . 4-18

4.9.4 Permanent Splicing. . . . . . . . . . . . 4-19

4.9.5 Emergency Splicing . . . . . . . . . . . 4-19

4.10 SHIELDED AND COAXIAL

CABLE . . . . . . . . . . . . . . . . . 4-21

4.10.1 Removing Insulation. . . . . . . . . . . 4-21

4.10.2 Connector Termination . . . . . . . . . 4-21

4.10.3 Grounding Sheath Termination . . . . 4-23

4.10.4 Attaching Pigtail Wires to Cable

Sheath . . . . . . . . . . . . . . . . . . 4-26

4.10.5 Emergency Splice. . . . . . . . . . . . . 4-27

4.10.6 Insulation Repair . . . . . . . . . . . . . 4-28

4.10.7 Stripping Coaxial Cable with Single

Conductor Shield . . . . . . . . . . . 4-28

4.11 CABLE BINDING AND

LACING. . . . . . . . . . . . . . . . . 4-28

4.11.1 Cable Lacing . . . . . . . . . . . . . . . . 4-28

4.11.2 Self-clinching Cable Straps . . . . . . 4-31

Change 10 i

4.11.3 Cable Strap Installation . . . . . . . . . 4-32

4.12 HIGH TEMPERATURE PRES-

SURE-SENSITIVE TAPE . . . . . 4-33

4.12.1 Spot Tying . . . . . . . . . . . . . . . . . 4-33

4.12.2 Spot Tying with Nylon Straps . . . . 4-33

4.13 CRIMPED ELECTRICAL

CONNECTIONS . . . . . . . . . . . 4-34

4.13.1 Types of Solderless Lugs. . . . . . . . 4-34

4.13.2 Crimping Tools . . . . . . . . . . . . . . 4-35

4.13.3 Crimping Procedure . . . . . . . . . . . 4-36

4.13.4 Crimp Inspection . . . . . . . . . . . . . 4-36

4.14 WIRE WRAPPED ELECTRICAL

CONNECTIONS . . . . . . . . . . . 4-36

4.14.1 Use . . . . . . . . . . . . . . . . . . . . . . 4-36

4.14.2 Procedure . . . . . . . . . . . . . . . . . . 4-36

4.15 BOLTED ELECTRICAL

CONNECTIONS . . . . . . . . . . . 4-37

4.16 INSULATING MATERIALS . . . . . 4-37

4.16.1 Coatings . . . . . . . . . . . . . . . . . . . 4-37

4.16.2 Standard Insulation Tubing . . . . . . 4-37

4.16.3 Heat-Shrinkable Tubing. . . . . . . . . 4-38

4.16.4 Plastic Tape. . . . . . . . . . . . . . . . . 4-39

4.17 POTTING OF CONNECTORS . . . 4-40

4.18 CLEANING PROCEDURES . . . . . 4-42

4.18.1 Moderate Contamination . . . . . . . . 4-42

4.18.2 Ultrasonic Cleaning . . . . . . . . . . . 4-43

4.18.3 Aerosol Cleaners . . . . . . . . . . . . . 4-45

4.18.4 Other Cleaning Techniques . . . . . . 4-45

4.18.5 Cleaning AN Connectors . . . . . . . . 4-45

4.18.6 Cleaning Group A and Group B

Components . . . . . . . . . . . . . . 4-46

4.18.7 Capacitor Leakage . . . . . . . . . . . . 4-46

4.18.8 Precious Metal Contacts . . . . . . . . 4-46

4.19 CORROSION PREVENTIVE

TREATMENTS . . . . . . . . . . . . 4-46

4.19.1 Equipment Exteriors . . . . . . . . . . . 4-46

4.19.2 Connectors . . . . . . . . . . . . . . . . . 4-46

4.19.3 Aluminum Alloy Parts . . . . . . . . . 4-46

4.19.4 Ferrous Alloys . . . . . . . . . . . . . . . 4-46

4.19.5 Cadmium Plated Parts. . . . . . . . . . 4-47

4.19.6 Magnesium and Magnesium

Alloys . . . . . . . . . . . . . . . . . . 4-47

4.19.7 Zinc and Zinc Plated Parts. . . . . . . 4-47

4.20 FUNGUS PREVENTION . . . . . . . 4-47

4.21 PRESSURIZATION TEST. . . . . . . 4-47

4.22 MARKING AND

IDENTIFICATION. . . . . . . . . . 4-47

4.23 TROUBLESHOOTING. . . . . . . . . 4-48

4.24 REPLACEMENT AND REPAIR OF

PARTS . . . . . . . . . . . . . . . . . . 4-48

4.24.1 Fuses . . . . . . . . . . . . . . . . . . . . . 4-48

4.24.2 Fuse Holders . . . . . . . . . . . . . . . . 4-56

4.24.3 Lamps . . . . . . . . . . . . . . . . . . . . 4-56

4.24.4 Resistors . . . . . . . . . . . . . . . . . . . 4-56

4.24.5 Capacitors . . . . . . . . . . . . . . . . . . 4-56

Chapter Page

4.24.6 Inductors and Transformers . . . . . . 4-56

4.24.7 Relays . . . . . . . . . . . . . . . . . . . . 4-56.1

4.24.8 Meters . . . . . . . . . . . . . . . . . . . . 4-56.1

4.24.9 Electron Tubes, General . . . . . . . . 4-56.1

4.24.10 Cathode Ray Tubes . . . . . . . . . . . 4-57

4.24.11 Semiconductor Devices . . . . . . . . . 4-58

4.24.12 MIL-C-25955 Connectors, MIL-S-

24251/3 Series . . . . . . . . . . . . . 4-60

4.24.13 Power Cords and Plugs . . . . . . . . . 4-62

4.24.14 Controls and Switches. . . . . . . . . . 4-63

4.24.15 Vibration Isolators . . . . . . . . . . . . 4-63

4.25 COMPONENT

SUBSTITUTION . . . . . . . . . . . 4-64

4.25.1 Fuses . . . . . . . . . . . . . . . . . . . . . 4-64

4.25.2 Resistors . . . . . . . . . . . . . . . . . . . 4-64

4.25.3 Capacitors . . . . . . . . . . . . . . . . . . 4-65

4.25.4 Switches . . . . . . . . . . . . . . . . . . . 4-65

4.25.5 Solid-State Devices. . . . . . . . . . . . 4-65

4.25.6 Electron Tubes. . . . . . . . . . . . . . . 4-65

4.25.7 Lamps . . . . . . . . . . . . . . . . . . . . 4-65

4.25.8 Neon Lamps . . . . . . . . . . . . . . . . 4-66

4.26 REPAIR OF ELECTRICAL CON-

TACT STRIPS. . . . . . . . . . . . . 4-66

4.26.1 Description . . . . . . . . . . . . . . . . . 4-66

4.26.2 Areas of Use . . . . . . . . . . . . . . . . 4-66

4.26.3 Problems. . . . . . . . . . . . . . . . . . . 4-66

4.26.4 Missing or Bent Contacts . . . . . . . 4-66

4.26.5 Manufacturers of Preformed Finger

Stock . . . . . . . . . . . . . . . . . . . 4-67

4.26.6 Mounting of Finger Stock . . . . . . . 4-67

4.26.7 Plating . . . . . . . . . . . . . . . . . . . . 4-67

4.26.8 Assembly of Cavity Resonators . . . 4-68

4.27 REPAIR OF WAVEGUIDE . . . . . . 4-68

4.27.1 Cure Cycle . . . . . . . . . . . . . . . . . 4-68

5 PRINTED CIRCUIT BOARD REPAIR . . . . . 5-1

5.1 GENERAL . . . . . . . . . . . . . . . . . 5-1

6 PROTECTIVE COATINGS . . . . . . . . . . . . . 6-1

6.1 GENERAL . . . . . . . . . . . . . . . . . 6-1

6.2 SPECIAL TOOLS . . . . . . . . . . . . 6-1

6.3 SPECIAL MATERIALS . . . . . . . . 6-1

6.4 SAFETY PRECAUTIONS. . . . . . . 6-2

6.4.1 Work Area . . . . . . . . . . . . . . . . . 6-2

6.4.2 Rotating Machinery . . . . . . . . . . . 6-2

6.4.3 Chemicals . . . . . . . . . . . . . . . . . . 6-2

6.4.4 Electronics . . . . . . . . . . . . . . . . . 6-2

6.5 REPAIR SEQUENCE . . . . . . . . . . 6-2

6.6 IDENTIFICATION OF

COATING. . . . . . . . . . . . . . . . 6-2

6.6.1 Preliminary Identification. . . . . . . . 6-2

6.6.2 Types of Coatings . . . . . . . . . . . . 6-3

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6.6.3 Identification Chart . . . . . . . . . . . . 6-3

6.6.4 Inspection . . . . . . . . . . . . . . . . . . 6-3

6.6.5 Ultraviolet Fluorescence . . . . . . . . 6-3

6.6.6 Acetone Test . . . . . . . . . . . . . . . . 6-3

6.6.7 Fingernail Test . . . . . . . . . . . . . . . 6-4

6.6.8 Burn Test . . . . . . . . . . . . . . . . . . 6-4

6.6.9 Color Test 1 . . . . . . . . . . . . . . . . 6-6

6.6.10 Color Test 2 . . . . . . . . . . . . . . . . 6-6

6.6.11 Color Comparison . . . . . . . . . . . . 6-6

6.7 REMOVAL OF COATING . . . . . . 6-7

6.7.1 Polyurethane and Epoxy . . . . . . . . 6-7

6.7.2 Parylene . . . . . . . . . . . . . . . . . . . 6-8

6.7.3 Acrylic . . . . . . . . . . . . . . . . . . . . 6-10

6.7.4 Silicone . . . . . . . . . . . . . . . . . . . 6-10

6.8 RECOATING REPAIRED

AREAS . . . . . . . . . . . . . . . . . 6-10

6.8.1 Washing of Boards . . . . . . . . . . . . 6-11

6.8.2 Polyurethane and Epoxy Coated

Boards . . . . . . . . . . . . . . . . . . 6-11

6.8.3 Parylene Coated Boards . . . . . . . . 6-12

6.8.4 Acrylic Coating . . . . . . . . . . . . . . 6-13

6.8.5 Silicone Coated Boards . . . . . . . . . 6-14

6.9 CONFORMAL COATING OF CE-

RAMIC PRINTED CIRCUITS

(CPC’S) . . . . . . . . . . . . . . . . . 6-17

6.9.1 Preparing Coating Material . . . . . . 6-17

6.9.2 Application of Coating . . . . . . . . . 6-17

6.9.3 Curing the Coating . . . . . . . . . . . . 6-17

6.9.4 Cleanup . . . . . . . . . . . . . . . . . . . 6-17

6.10 PROTECTIVE COATING

ACCEPTANCE . . . . . . . . . . . . 6-17

6.11 VARNISH-TYPE COATINGS . . . . 6-18

6.11.1 Sealing . . . . . . . . . . . . . . . . . . . . 6-18

6.11.2 High-Voltage Circuits . . . . . . . . . . 6-18

7 ELECTROSTATIC DISCHARGE

CONTROL . . . . . . . . . . . . . . . . . . . . . . 7-1

7.1 GENERAL . . . . . . . . . . . . . . . . . 7-1

7.1.1 Purpose . . . . . . . . . . . . . . . . . . . 7-1

7.1.2 Scope . . . . . . . . . . . . . . . . . . . . . 7-1

7.1.3 Applicability . . . . . . . . . . . . . . . . 7-1

7.2 REFERENCES . . . . . . . . . . . . . . 7-1

7.3 SUMMARY OF ESD

PRINCIPLES . . . . . . . . . . . . . 7-2

7.3.1 Static Electricity. . . . . . . . . . . . . . 7-2

7.3.2 Sources of Static Electricity . . . . . . 7-2

7.3.3 ESD Parameters . . . . . . . . . . . . . . 7-3

7.3.4 Failure Mechanisms . . . . . . . . . . . 7-4

7.3.5 Failure Types. . . . . . . . . . . . . . . . 7-4

7.3.6 Common ESD Misconceptions . . . . 7-5

7.4 ESD SUSCEPTIBILITY . . . . . . . . 7-5

7.4.1 Susceptible Items . . . . . . . . . . . . . 7-5

7.4.2 When Does ESD Susceptibility

Stop . . . . . . . . . . . . . . . . . . . . 7-6

Chapter Page

7.4.3 ESD Sensitivity Defined . . . . . . . . 7-6

7.5 FRAMEWORK OF ESD

CONTROL . . . . . . . . . . . . . . . 7-7

7.5.1 Work Area ESD Control

Surveys . . . . . . . . . . . . . . . . . 7-7

7.5.2 ESD Control Strategies . . . . . . . . . 7-7

7.5.3 Conductive/Static Dissipative/Non-

Charge Generating Materials . . . 7-7

7.5.4 ESD Control Products. . . . . . . . . . 7-8

7.5.5 Principle Components . . . . . . . . . . 7-8

7.5.6 Grounding. . . . . . . . . . . . . . . . . . 7-34.1

7.5.7 Cleaning of ESDS Items . . . . . . . . 7-42

7.6 OPERATING PROCEDURES . . . . 7-42

7.7 WORK AREA ESD CONTROL

SURVEYS . . . . . . . . . . . . . . . 7-48

7.7.1 Background . . . . . . . . . . . . . . . . . 7-48

7.7.2 General. . . . . . . . . . . . . . . . . . . . 7-48

7.7.3 Performing Work Area ESD Control

Surveys . . . . . . . . . . . . . . . . . 7-48

7.7.4 ESD Control Product

Requirements. . . . . . . . . . . . . . 7-48

7.7.5 Work Area ESD Control

Checklist. . . . . . . . . . . . . . . . . 7-51

7.8 PERIODIC TESTING OF ESD

CONTROL PRODUCTS . . . . . . 7-52

7.8.1 Work Surface Test Procedures . . . . 7-52

7.8.2 Storage Cabinet and Shelf Test

Procedures . . . . . . . . . . . . . . . 7-52

7.8.3 Flooring Test Procedures . . . . . . . . 7-53

7.8.4 Wrist Strap Test Procedures . . . . . . 7-54

7.8.5 Footwear Test Procedures . . . . . . . 7-54

7.8.6 Test Procedures for Electrical

Ionizers . . . . . . . . . . . . . . . . . 7-54

7.8.7 Seating Test Procedures. . . . . . . . . 7-56

7.8.8 Shielding Bag Test Procedures . . . . 7-56

7.8.9 Conductive/Static Dissipative Finger

Cots and Gloves. . . . . . . . . . . . 7-56

7.8.10 ESD Workstation Grounding Test

Procedures . . . . . . . . . . . . . . . 7-57

7.8.11 Soldering Equipment Test . . . . . . . 7-58

7.8.12 Compressed Air, Hot Air Blowers, Dry Nitrogen and Vacuum Nozzle Ground Test Procedures. . . . . . . 7-58

8 FRONT PANEL REPAIR. . . . . . . . . . . . . . . 8-1

8.1 GENERAL . . . . . . . . . . . . . . . . . 8-1

8.2 TYPES OF FRONT PANELS . . . . 8-1

8.2.1 Exterior Lighted Front Panels. . . . . 8-1

8.2.2 Illuminated Front Panels . . . . . . . . 8-1

8.3 TOOLS AND ACCESSORIES . . . . 8-1

8.4 MATERIALS . . . . . . . . . . . . . . . 8-1

8.5 GENERAL PRECAUTIONS . . . . . 8-1

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8.6 CLEANING . . . . . . . . . . . . . . . . 8-1

8.7 INSPECTION . . . . . . . . . . . . . . . 8-2

8.8 INITIAL TESTING (FRONT

PANEL REMOVED FROM

LRU) . . . . . . . . . . . . . . . . . . . 8-3

8.9 TROUBLESHOOTING. . . . . . . . . 8-3

8.10 REPAIR OF CRACKED OR BRO-

KEN PANELS . . . . . . . . . . . . . 8-3

8.11 REPAIR OF BROKEN

CORNERS . . . . . . . . . . . . . . . 8-3

8.12 REPAIR OF BROKEN BUSS

WIRE. . . . . . . . . . . . . . . . . . . 8-4

8.13 REPLACEMENT OF FAULTY

BULBS . . . . . . . . . . . . . . . . . 8-7

8.14 REMOVAL/REPLACEMENT OF

FILTERS/ REFLECTORS . . . . . 8-8

8.15 FILLING EXCAVATION . . . . . . . 8-8

Chapter Page

8.16 REMOVAL, REPLACEMENT OF

FILTER BRACKET, PILE FAS-

TENERS AND

ANNUNCIATORS . . . . . . . . . . 8-9

8.17 SANDING . . . . . . . . . . . . . . . . . 8-10

8.18 MIXING AND PAINTING PRIMER

INK . . . . . . . . . . . . . . . . . . . . 8-10

8.19 MIXING AND PAINTING BACK-

GROUND INK . . . . . . . . . . . . 8-10

8.20 SILKSCREENING . . . . . . . . . . . . 8-10

8.21 CLEAR EPOXY INK

APPLICATION . . . . . . . . . . . . 8-11

8.22 WIRING BULB LOCATION

STENCILING . . . . . . . . . . . . . 8-11

8.23 CONNECTOR PLUG REMOVAL

REPLACEMENT. . . . . . . . . . . 8-12

8.24 FINAL TESTING. . . . . . . . . . . . . 8-13

TO 00-25-234

iv Change 2

9 FLEXIBLE PRINTED CIRCUIT REPAIR

PROCEDURES . . . . . . . . . . . . . . . . . . . 9-1

9.1 GENERAL . . . . . . . . . . . . . . . . . 9-1

10 SUSPECTED COUNTERFEIT PARTS OR

MATERIAL. . . . . . . . . . . . . . . . . . . . . . 10-1

10.1 GENERAL . . . . . . . . . . . . . . . . . 10-1

Chapter Page

10.1.1 Counterfeit Materiel . . . . . . . . . . . 10-1

10.1.2 Suspect Counterfeit Materiel . . . . . 10-1

GLOSSARY . . . . . . . . . . . . . . . . . . . . . Glossary 1

INDEX . . . . . . . . . . . . . . . . . . . . . . . . . Index 1

TO 00-25-234

v

LIST OF ILLUSTRATIONS

Number PageTitle

2-1 Chassis-Type Electronic Assembly, Protec-tive Packaging . . . . . . . . . . . . . . . . . 2-4

2-2 Circuit Board-Type Electronic Assembly, Protective Packaging . . . . . . . . . . . . . 2-4

2-3 Plug-In Type Electronic Assembly, Protec-tive Packaging . . . . . . . . . . . . . . . . . 2-5

4-1 Typical Scribe . . . . . . . . . . . . . . . . . . . 4-4 4-2 Typical Chassis Punch. . . . . . . . . . . . . . 4-5 4-3 Application of Dowel Pin . . . . . . . . . . . 4-5 4-4 Application of Tapered Pins . . . . . . . . . . 4-5 4-5 Typical Drive Pins and Spring Pins . . . . . 4-5 4-6 Clevis Pin . . . . . . . . . . . . . . . . . . . . . . 4-6 4-7 Countersunk and Skin-Dimpled Rivet

Holes . . . . . . . . . . . . . . . . . . . . . . . 4-6 4-8 Bucking Bar Recess . . . . . . . . . . . . . . . 4-6 4-9 Rivet Head Criteria . . . . . . . . . . . . . . . . 4-7 4-10 Properly and Improperly Set Rivets . . . . . 4-7 4-11 Acceptable and Unacceptable Eyelets . . . 4-7 4-12 Typical Studs and Terminals. . . . . . . . . . 4-8 4-13 Typical Retaining Rings. . . . . . . . . . . . . 4-8 4-14 Tapped Hole Specifications . . . . . . . . . . 4-9 4-15 Anchor Nuts, Clinch Nut, and Plug

Nut. . . . . . . . . . . . . . . . . . . . . . . . . 4-10 4-16 Typical Lockwashers . . . . . . . . . . . . . . . 4-12 4-17 Double Twist Safety Wiring . . . . . . . . . . 4-13 4-18 Single Wire Method . . . . . . . . . . . . . . . 4-13 4-19 Use of Wire Twister . . . . . . . . . . . . . . . 4-14 4-20 V-Band Coupling Safety Wiring

Techniques . . . . . . . . . . . . . . . . . . . 4-16 4-21 Safety Wiring AN Connectors. . . . . . . . . 4-17 4-22 Safety Wiring AN Connector to

Structure . . . . . . . . . . . . . . . . . . . . . 4-17 4-23 Safety Wiring AN Split-Shell Assembly

Screws . . . . . . . . . . . . . . . . . . . . . . 4-18 4-24 Typical Clamps . . . . . . . . . . . . . . . . . . 4-18 4-25 Pre-Insulated Permanent Copper

Splices . . . . . . . . . . . . . . . . . . . . . . 4-19 4-26 Terminal Lug Barrel Splice . . . . . . . . . . 4-21 4-27 Splicing Broken Wire by Soldering . . . . . 4-21 4-28 Shop Aids for Stripping Insulation from

Coaxial Cables . . . . . . . . . . . . . . . . . 4-22 4-29 Attaching Improved N Connectors to Co-axial Cable . . . . . . . . . . . . . . . . . . . 4-24 4-30 Grounding Sheath Termination for

Shielded Wire . . . . . . . . . . . . . . . . . 4-25 4-31 Soldered On Pigtail Preparation . . . . . . . 4-27 4-32 Common-Point Pigtail Splice . . . . . . . . . 4-27 4-33 Several Shields in One Set of

Sleeves . . . . . . . . . . . . . . . . . . . . . . 4-27 4-34 Typical Cascading Pigtails . . . . . . . . . . . 4-29 4-35 Braid Dead-Ending . . . . . . . . . . . . . . . . 4-29

Number PageTitle

4-36 Starting a Cable Lace . . . . . . . . . . . . . . 4-30 4-37 Cable Stitching. . . . . . . . . . . . . . . . . . . 4-30 4-38 Cable Lace Termination. . . . . . . . . . . . . 4-30 4-39 Cable Branching. . . . . . . . . . . . . . . . . . 4-30 4-40 Strap Configuration. . . . . . . . . . . . . . . . 4-31 4-41 Installing Self-Clinching Plastic Cable

Straps . . . . . . . . . . . . . . . . . . . . . . . 4-32 4-42 MS90387 Adjustable Hand Tools for In-stalling Self-Clinching Plastic Tiedown Straps . . . . . . . . . . . . . . . . . . . . . . . 4-33

4-43 Cable Lace, Spot Tie. . . . . . . . . . . . . . . 4-33 4-44 Nylon Strapped Spot Tie . . . . . . . . . . . . 4-34 4-45 Solderless Terminal Lugs . . . . . . . . . . . . 4-35 4-46 Pre-Insulated Terminal Lug Cutaway . . . . 4-36 4-47 Insulating Sleeves . . . . . . . . . . . . . . . . . 4-36 4-48 Inserting Aluminum Wire Into Aluminum

Terminal Lugs . . . . . . . . . . . . . . . . . 4-37 4-49 Hand Crimping Tools for Pre-Insulated

Terminals . . . . . . . . . . . . . . . . . . . . 4-38 4-50 Hand Crimping Tool, Aluminum

Terminals . . . . . . . . . . . . . . . . . . . . 4-39 4-51 Power Crimping Tools. . . . . . . . . . . . . . 4-39 4-52 Inserting Terminal Lug Into Hand

Tool . . . . . . . . . . . . . . . . . . . . . . . . 4-40 4-53 Wire Wrapping Tool in Use . . . . . . . . . . 4-41 4-54 Wire Wrapping Technique . . . . . . . . . . . 4-42 4-55 Typical Bolted Connections . . . . . . . . . . 4-43 4-56 Electric Hot-Air Gun. . . . . . . . . . . . . . . 4-43 4-57 Spare Wires for Potted Connector . . . . . . 4-43 4-58 Cleaning Connector Prior to Potting . . . . 4-44 4-59 Filling and Curing Potted Connector . . . . 4-44 4-60 Installation of O-Ring on Potted

Connector . . . . . . . . . . . . . . . . . . . . 4-44 4-61 Slow-Blow Fuse . . . . . . . . . . . . . . . . . . 4-49 4-62 Military Fuse Designations. . . . . . . . . . . 4-55 4-63 Correct Wiring of Instrument-Type Fuse

Holder . . . . . . . . . . . . . . . . . . . . . . 4-57 4-64 Correct Wiring for Fuse Holders Contain-ing Indicator Lights . . . . . . . . . . . . . 4-59 4-65 Wiring Diagrams For Indicator Type Fuse

Holders . . . . . . . . . . . . . . . . . . . . . . 4-61 4-66 Repair of Power Cords . . . . . . . . . . . . . 4-63 4-67 Power Cord Assembly . . . . . . . . . . . . . . 4-64 4-68 Acceptable and Unacceptable Control

Knob Damage . . . . . . . . . . . . . . . . . 4-66 6-1 Flow Diagram for Identification of MIL-I-

46058 Conformal Coatings. . . . . . . . . 6-5 6-2 Conformal Coating Fillet . . . . . . . . . . . . 6-6 6-3 Fingernail Test . . . . . . . . . . . . . . . . . . . 6-6 vi Change 6

Number PageTitle

6-4 Color Test 2 Setup . . . . . . . . . . . . . . . . 6-9 6-5 Removing Polyurethane Coating from

Lead. . . . . . . . . . . . . . . . . . . . . . . . 6-9 6-6 Removing Polyurethane Coating or

Fillets . . . . . . . . . . . . . . . . . . . . . . . 6-9 6-7 Removing Coatings and Fillets from Axial

Components. . . . . . . . . . . . . . . . . . . 6-11 6-8 Drying or Curing Schedule for Coating

Material Applied Shortly After Mixing . . . . . . . . . . . . . . . . . . . . . . 6-15

6-9 Drying or Curing Schedule for Coating Material Applied Near End of Work Life . . . . . . . . . . . . . . . . . . . . . . . . 6-16

7-1 Reasons for Device Failure Due to

ESD . . . . . . . . . . . . . . . . . . . . . . . . 7-4

7-2 Dielectric Failure in 3N157 MOSFET at 5000X . . . . . . . . . . . . . . . . . . . . . . 7-5

7-3 Permanent Static Control Workstation . . . 7-8 7-4 Static Control Workstation (work cush-ioned or rigid work surface on an exist-ing work bench) . . . . . . . . . . . . . . . . 7-9

7-5 Portable Static Control Workstation . . . . . 7-9

Number PageTitle

7-6 Bench Top Ionizer Positioning . . . . . . . . 7-11 7-7 First Touch Installation Procedures . . . . . 7-13 7-8 MIL-STD-1285 Symbol. . . . . . . . . . . . . 7-20 7-9 ESD Attention Label/No Further Packag-ing Required . . . . . . . . . . . . . . . . . . 7-20 7-10 ESD Control Label/ESDS Item Packages

(MIL-STD-129) . . . . . . . . . . . . . . . . 7-20

7-11 ESD Caution Label/Off Base Transport

Items (MIL-STD-129) . . . . . . . . . . . . 7-20.1 7-12 Typical Electrical AC Outlet. . . . . . . . . . 7-35 7-13 Typical Service Entrance . . . . . . . . . . . . 7-37 7-14 Flow Chart for ESD Control Workstation

Grounding . . . . . . . . . . . . . . . . . . . . 7-41 7-15 Typical ESD Protective Area Sign . . . . . . 7-46 8-1 Typical Stencil/Diagram. . . . . . . . . . . . . 8-5 8-2 Cracked Panel Repair . . . . . . . . . . . . . . 8-6 8-3 Clinched Splice . . . . . . . . . . . . . . . . . . 8-8 8-4 Typical Bulb Insert . . . . . . . . . . . . . . . . 8-8 8-5 Buss Wire Connection . . . . . . . . . . . . . . 8-13 8-6 Typical Excavated Plug . . . . . . . . . . . . . 8-13 8-7 Front Panel Mold . . . . . . . . . . . . . . . . . 8-14

LIST OF TABLES

Number PageTitle

1-1 Recommended Tools . . . . . . . . . . . . . . . 1-1 4-1 Recommended Materials . . . . . . . . . . . . 4-2 4-2 Pre-Insulated Copper Splices and Crimp-ing Tools . . . . . . . . . . . . . . . . . . . . . 4-19 4-3 Shielded Wire Terminations, Inner

Sleeves . . . . . . . . . . . . . . . . . . . . . . 4-25 4-4 Shielded Wire Terminations, Outer Sleeves and Installing Tools. . . . . . . . . . . . . . 4-25 4-5 Self-Clinching Plastic Cable Straps and

Installation Tools . . . . . . . . . . . . . . . 4-31 4-6 Typical Heat-Shrinkable Tubing Sizes . . . 4-39 4-7 Cleaning Moderately Contaminated

Devices. . . . . . . . . . . . . . . . . . . . . . 4-45 4-8 Types of Organic Solvents . . . . . . . . . . . 4-45 4-9 Cross Reference, Military and Commercial

Fuses . . . . . . . . . . . . . . . . . . . . . . . 4-49 4-10 Limitations for CRT Dead Spots . . . . . . . 4-57 6-1 Special Materials for Conformal

Coating . . . . . . . . . . . . . . . . . . . . . . 6-1

Number PageTitle

6-2 Repair Sequence. . . . . . . . . . . . . . . . . . 6-2 6-3 Color Test and Identification of Conformal

Coatings . . . . . . . . . . . . . . . . . . . . . 6-7 6-4 Coating Repair Process . . . . . . . . . . . . . 6-10 6-5 Polyurethane Recoat System. . . . . . . . . . 6-12 7-1 Typical Sources of Static Electricity . . . . 7-2 7-2 Typical Electrostatic Voltages Generated by Personnel . . . . . . . . . . . . . . . . . . 7-3 7-3 ESD Protective Equipment . . . . . . . . . . . 7-20.1 7-4 Effects of Electrical Current on Humans

(Reference MIL-STD-454) . . . . . . . . . 7-40 7-5 Summary of ESD Periodic Testing Time

Intervals . . . . . . . . . . . . . . . . . . . . . 7-47 8-1 Equipment Used for Front Panel

Repair. . . . . . . . . . . . . . . . . . . . . . . 8-1 8-2 Consumable Materials Required for Front

Panel Repair . . . . . . . . . . . . . . . . . . 8-2

TO 00-25-234

LIST OF ILLUSTRATIONS - CONTINUED

Change 8 vii/(viii blank)

INTRODUCTION

1 PURPOSE.

This technical order establishes standard shop practices for repair, maintenance, and test of electronic/electric equipment, and is the authorizing document for maintenance and replace-ment procedures where authorized procedures are unavail-able. The purpose of this technical order is to provide the uniform criteria and basic work specifications required to process electronic/electric equipment when applicable direc-tives are unavailable.

2 SCOPE.

The provisions contained herein are applicable to Air Force and contractual personnel engaged in repair, maintenance, or test of Aerospace Electronic/Electric Equipment.

NOTE

Although this is a general TO, there are unique requirements in Chapter 7 for anyone involved with handling ESD sensitive items, including es-tablishing an ESD Control Program. Chapter 7 also includes requirements for use of approved ESD control materials and procedures that are necessary for safe handling, packaging, and trans-portation of ESD sensitive items. Many equipment specific technical orders (TOs), however, lack suf-ficient ESD information and procedures to prop-erly protect ESD sensitive items. When there is conflict in requirements of this TO and ESD con-trol procedures outlined in equipment specific TOs, relevant SMEs should be contacted to determine appropriate action. In cases where it is determined that the requirements in Chapter 7 offer current best practices, an AFTO 22 should be submitted against the equipment specific TO modifying it to refer to Chapter 7 for ESD control guidance. In other cases, Chapter 7 should be updated to in-clude new best practices for ESD control.

1 Introduction

2 Workmanship

3 Soldering

4 General Repair

5 Printed Circuit Board Repair *

6 Protective Coatings

7 Electrostatic Discharge Control

8 Front Panel Repair

9 Flexible Printed Circuit Repair Procedures *

10 Suspected Counterfeit Parts or Materiel

* See also TO 00-25-259

3 ABBREVIATIONS.

All abbreviations used in this manual are shown in the list of abbreviations below. Standard abbreviations are in accor-dance with ASME Y14.38, Abbreviations and Acronyms for Use on Drawings and Related Documents.

AF Air Force

AFTO Air Force Technical Order

CAGE Commercial and Government Entity

CD Compact Disk

CFE Contractor Furnished Equipment

DoD Department of Defense

ETIMS Enhanced Technical Information Manage-ment System

GFE Government Furnished Equipment

in. Inch or Inches

No. Number

PN Part Number

REF Reference

TO Technical Order

4 RELATED PUBLICATIONS.

NOTE

When searching Technical Order (TO) numbers in the Enhanced Technical Information Management System (ETIMS) catalog, please use the wildcard (*) after typing in the TO number. Many TOs are not available in paper format, (i.e., digital (WA-1) or Compact Disk (CD-1)). This ensures TOs in all media formats will populate the search.

The following publications contain information in support of this technical manual.

List of Related Publications

Number Title

AFI 21-101 Aircraft and Equipment Maintenance Management

ASME Y14.38 Abbreviations and Acronyms for Use on Drawings and Related Documents

Change 11 ix

List of Related Publications - Continued

Number Title

ASME Y14.44 Reference Designation for Electrical and Electronic Parts and Equipment

SAE AS5553 Counterfeit Electrical, Elec-tronic, and Electromechani-cal (EEE) Parts: Avoidance, Detection, Mitigation, and Disposition

SAE AS6174 Counterfeit Material: Assur-ing Acquisition of Authentic and Conforming Material

TO 00-5-1 Air Force Technical Order System

TO 00-25-234 General Shop Practice Re-quirements for the Repair, Maintenance, and Test of Electrical Equipment

TO 00-25-251 Installation, Operation, Maintenance, Care and Han-dling Instructions, General Microwave Tubes, Magne-tron Tubes, Electron Tubes

TO 00-25-259 Standard Maintenance Prac-tices Miniature/Microminia-ture (2M) Electronic Assem-bly Repair Organizational/ Intermediate/Depot Level

List of Related Publications - Continued

Number Title

TO 00-35D-54 USAF Deficiency Reporting, Investigation and Resolu-tion.<

TO 1-1A-8 Engineering Manual Series Aircraft and Missile Repair Structural Hardware

TO 1-1A-14 Installation and Repair Prac-tices Volume 1 Aircraft Elec-tric and Electronic Wiring

TO 1-1A-15 General Maintenance In-structions For Support Equipment (SE)

TO 33-1-32 General Instructions for In-put Power Wiring of Electri-cal/Electronic Support Equipment<

TO 44H1-1-117 General Installation of Heli-coil Inserts

5 RECORD OF APPLICABLE TIME COMPLIANCE

TECHNICAL ORDERS (TCTOS).

List of Time Compliance Technical Orders

TCTO

Number

TCTO

Title

TCTO

Date

None

6 HARDNESS CRITICAL ITEMS (HCI).

The HCI symbol ( ) establishes special require-ments limiting changes and substitutions and that the specific parts listed must be used to ensure hardness is not degraded.

If included, items with nuclear survivability requirements are marked with the HCI symbol ( ). All changes to, or pro-posed substitutions of, HCIs must be approved by the ac-quiring activity.

7 ELECTROSTATIC DISCHARGE SENSITIVE

(ESDS) ITEMS.

All ESDS parts shall be handled in accordance with the ESDS device handling procedures in TO 00-25-234.

If included, items containing ESDS parts are marked with the ESDS symbol ( ).

8 IMPROVEMENT REPORTS.

Recommended changes to this manual shall be submitted in accordance with TO 00-5-1.

x Change 11

SAFETY SUMMARY

1 GENERAL SAFETY INSTRUCTIONS.

This manual describes physical and/or chemical processes which may cause injury or death to personnel, or damage to equipment, if not properly followed. This safety summary includes general safety precautions and instructions that must be understood and applied during operation and maintenance to ensure personnel safety and protection of equipment. Prior to performing any specific task, the WARNINGs, CAU- TIONs, and NOTEs included in that task shall be reviewed and understood.

2 WARNINGS, CAUTIONS, AND NOTES.

WARNINGs and CAUTIONs are used in this manual to highlight operating or maintenance procedures, practices, conditions, or statements which are considered essential to protection of personnel (WARNING) or equipment (CAU- TION). WARNINGs and CAUTIONs immediately precede the step or procedure to which they apply. WARNINGs and CAUTIONs consist of four parts: heading (WARNING, CAUTION, or icon), a statement of the hazard, minimum precautions, and possible results if disregarded. NOTEs are used in this manual to highlight operating or maintenance procedures, practices, conditions, or statements which are not essential to protection of personnel or equipment. NOTEs may precede or follow the step or procedure, depending upon the information to be highlighted. The headings used and their definitions are as follows:

Highlights an essential operating or maintenance procedure, practice, condition, statement, etc., which if not strictly observed, could result in in-jury to, or death of, personnel or long term health hazards.

Highlights an essential operating or maintenance procedure, practice, condition, statement, etc., which if not strictly observed, could result in dam-age to, or destruction of, equipment or loss of mis-sion effectiveness.

NOTE

Highlights an essential operating or maintenance procedure, condition, or statement.

3 HAZARDOUS MATERIALS WARNINGS.

Hazardous Materials Warnings in this manual are provided through use of the Hazardous Symbols listed below. Consult the HAZARDOUS MATERIALS DESCRIPTION below or Material Safety Data Sheets (MSDS) (Occupational Safety and Health Administration on hazards, effects, and protective equipment requirements. If you do not have an MSDS for the material involved, contact your supervisor, or the base Safety or Bioenvironmental Engineering Offices.

3.1 Hazardous Materials Icons. Icons are used in this

manual to identify dangers associated with hazardous mate-rials. The icons used and their definitions are as follows.

The abstract symbol bug shows that a material may contain bac-teria or viruses that present a danger to life or health.

The symbol of drops of liquid onto a hand shows that the ma-terial will cause burns or irrita-tion of skin and tissue.

The rapidly expanding symbol shows that the material may explode if subjected to high temperatures, sources of ignition or high pressure.

The symbol of a person wearing goggles shows that the material will injure eyes.

The symbol of a flame shows that the material can ignite and burn.

The symbol of a skull and crossbones shows that the mate-rial is poisonous or a danger to life.

The symbol of a liquid entering the mouth shows that eating or drinking this material can cause a health hazard.

Change 10 xi

The symbol of three circular wedges shows that radioactive energy is emitted which can in-jure tissue and organs.

The hand symbol shows a mate-rial that can irritate the skin or enter the body through the skin and cause a health hazard.

3.2 Hazardous Materials Description. The following

hazardous materials are used in this manual. Each icon rep-resents certain hazards as described above. Beneath the icons is the hazardous material name and a reference number. Be-low the icons, material name, and reference number is a de-scription of the hazardous material. Only the icons, material name, and reference number are used in the text of the manual. If a full description of the hazardous material is required while performing procedures in this manual, use the reference number to locate the appropriate description be-low.

THREAD COMPOUND, MIL-C-38736 1

Thread Compound, MIL-C-38736, if flammable and toxic to eyes, skin, and respiratory tract. Skin and eye protection re-quired. Avoid repeated or prolonged exposure. Keep Thread Compound, MIL-C-38736, off skin, eyes, and clothes; do not breathe vapors. Keep away from open flames or other sources of ignition.

AMINE ACID HALOGENATED ORGANIC SOL-

VENT, MIL-S-4784 2

Amine Acid Halogenated Organic Solvent, MIL-S-4784, contains trace amounts of bacteria and is toxic to eyes, skin, and respiratory tracts. Respirator, skin and eye protection required. Keep Amine Acid Halogenated Organic Solvent, MIL-S-4784, off skin, eyes, and clothes; do not breathe va-pors. Keep away from open flames or other sources of igni-tion.

ELECTRON TUBE, OA2 3

Electron Tube, OA2, contains radioactive material. Avoid re-peated or prolonged exposure. TO 33DA21-410-1 lists pro-tective equipment required and provides instructions for safe handling and disposal of radioactive tubes.

RTV 3140 ADHESIVE SEALANT, SILICONE, MIL-

A-46146, GROUP 1, TYPE 2 4

RTV 3140 Adhesive Sealant, Silicone, MIL-A-46146, Group 1, Type 2 is an eye, skin and respiratory irritant. Use in a well ventilated area. Appropriate skin and eye protection must be worn. Do not ingest. Keep container tightly closed when not in use. Store in a cool, dry, ventilated area, away from incompatible substances.

4 SAFETY PRECAUTIONS.

The following safety precautions shall be observed while performing procedures in this manual.

• Dangerous voltages are present at system connec-tors. Ensure power is OFF prior to connecting or disconnecting cables.

• Do not wear metal frame glasses, rings, watches, or other metal jewelry while working on electronic equipment.

• Some cleaning materials specified herein are flam-mable and/or toxic. Keep away from open flame or other ignition sources. Provide adequate ventilation and avoid skin/eye exposure.

• Cleaning with compressed air can create airborne particles that may enter eyes or penetrate skin. Pres-sure shall not exceed 30 psig. Wear goggles. Do not direct compressed air against skin.

xii Change 10

Isopropyl Alcohol is flammable and toxic to skin, eyes and respiratory tract. Skin and eye protection is required. Avoid repeated or pro-longed contact.

Use only in well ventilated areas. Do not use syn-thetic wiping cloths with flammable TT-I-735 iso-propyl alcohol. Keep away from open flames or other sources of ignition.

5 USE OF LIQUID SOLDER FLUX, MIL-F-14256.

Liquid Solder Flux, MIL-F-14256, is commonly used throughout this manual. It is flammable and toxic to skin, eyes, and respiratory tract. Good general ventilation is nor-mally adequate. Avoid skin and eye contact. Avoid all sources of ignition.

6 GIVE CLEANERS/CHEMICALS SPECIAL CARE.

NOTE

Unused or waste chemical substances may be haz-ardous and must be disposed of in accordance with Federal, State and Local directives. Contact Base Environmental Personnel for specific disposal in-structions.

Keep cleaners/chemicals in approved safety containers and in minimum quantities. Some cleaners/chemicals may have an adverse affect on skin, eyes, and respiratory tract. Ob-serve manufacturer’s warning labels and current safety di-rectives. Use cleaners/chemicals only in authorized areas.

Discard soiled cloths into safety cans. Consult the local Bioenvironmental Engineer and/or Material Safety Data Sheet (MSDS) for specific precautions, protective equipment, and ventilation requirements.

7 SOLDERING.

Avoid breathing fumes generated from soldering. Various metals have the potential to generate hazardous atmospheres.

Good general ventilation is normally adequate. Eye protec-tion is required. Before soldering, refer to TO 00-25-259 for procedures and consult the local Bioenvironmental Engineer for information on unfamiliar metals.

8 KEEP AWAY FROM LIVE CIRCUITS.

Operating personnel must think safety at all times. Do not replace components or make adjustments inside equipment with the electrical supply turned on. Under certain condi-tions, danger may exist even when the power control is in the off position due to charges retained by capacitors. To avoid injuries, always remove power from, discharge, and ground circuit before touching it. Adhere to all lock out/tag out requirements.

9 ELECTROSTATIC DISCHARGE (ESD).

Certain circuit card assemblies and their components will be damaged by seemingly undetectable electrostatic discharge.

Care must be exercised during handling/repair of these items.

Use electrostatic discharge (ESD) precautionary procedures outlined in TO 00-25-234.

10 DO NOT SERVICE OR ADJUST ALONE.

Do not attempt internal service or adjustment of equipment unless another person capable of rendering aid and resusci-tation is present.

11 USE CORRECT TECHNICAL DATA.

Do not attempt to repair or adjust and/or perform general maintenance on equipment without the correct technical data.

12 USE OF EQUIVALENT TEST EQUIPMENT.

Numerous end item repair manuals and Technical Orders, state Equivalent Test Equipment is authorized for use. The description of Equivalent is: All items of approved test ap-paratus shall be considered Equivalent if the measurement accuracy conforms to generally acceptable laboratory stan-dards, and are appropriate for the measurement of the appli-cable item being measured or tested.

Change 10 xiii/(xiv blank)All data on pages xv through xvi deleted

CHAPTER 1

INTRODUCTION

1.1 MATERIALS AND PARTS.

Materials and parts used in the repair of electronic equip-ment generally will be items covered by specification and itemized in Qualified Products Lists. These documents are subject to periodic amendments and revisions and their use shall supersede existing directives upon date of issue, unless otherwise directed. Materials and parts not so designated shall be of the best commercial quality, of the lightest weight, and suitable in all aspects for the intended application.

1.2 PARTS SUBSTITUTION.

To reduce the time that electronic equipment is out of ser-vice, equivalent parts can be substituted for unavailable parts.

General criteria for equivalent parts is established in Chapter 4 of this document.

1.3 ECONOMICAL REPAIR.

To attain and maintain the most economical repair posture, unserviceable parts and assemblies, regardless of ERRC cod-ing, for which parts availability can be determined from Il-lustrated Parts Catalogs (-4 TOs/IPBs), Material Require-ments (MRLs) or G-004A System (Maintenance Engineering Management System), shall be repaired when inspection re-veals them to be in a repairable condition. Exception: Those parts/assemblies that are to be replaced as the result of modi-fication. Replace unserviceable parts with serviceable parts when inspection reveals the unserviceable parts to be worn or damaged beyond a repairable condition. Parts worn or damaged beyond a repairable condition shall be condition condemned in accordance with AFMAN 23-110, pertaining Volume and Chapter.

1.4 RECOMMENDED TOOLS.

The tools (or their equivalents) listed in Table 1-1 are those recommended for general shop practices in the repair, main-tenance, and test of electronic equipment. Tools are listed by functional area; tools required for a functional area are in addition to those elsewhere in the list.

Table 1-1. Recommended Tools

Item NSN/Spec/Part Number

GENERAL REPAIR

Brush acid NSN 7920-00-223-8005

Chassis punch NSL *

Crimping tool aluminum lug MS25020

Crimping tool, power NSL

Crimping tool, splice AMP PN’s 49430, 49556, 48431, 49557, 59062, 59118

Burndy PN’s MR8-1A, MR8-335

Crimping tool, terminal lug MS25037

Eraser, typewriter AA-132

Hot-air gun, electric NSN 4940-00-314-9789

Installation tool, tie strap PN GS-2B, Panduit Corp

Insulation stripper NSN 5110-00-996-9389

Pin replacement tools (for MS24230 connectors) PN 036052-0000, 036069-0000

Scriber, machinist NSN 5120-00-224-9728

Soldering aids NSN 3439-00-629-2697

Soldering center NSN 4940-00-445-5965

Thermal shunts (heat sinks) NSN 5999-00-076-1279

Twister, safety wire NSN 5120-00-305-2306

Wire bending tool NSN 5120-00-239-8252

NSN 5120-00-188-3251

Wire wrapping tool NSN 5120-00-808-6005

1-1

Table 1-1. Recommended Tools - Continued

Item NSN/Spec/Part Number

PRINTED CIRCUIT BOARD REPAIR

Grounding kit PN 4111, Biggom Enterprises, Inc.

Anvil, jeweler’s NSN 5120-00-618-4913

Arbor and band set NSN 6520-00-500-9500

Blade kit:

blade, surgical, no. 11 NSN 6515-00-043-1770 blade, surgical, no. 20 NSN 6515-00-044-1921 blade, surgical, no. 25 NSN 6515-00-299-8055 blade, surgical, no. 15 NSN 6515-01-009-5293 blade, surgical, no. 12 NSN 6515-01-009-5294 blade, surgical, no. 10 NSN 6515-01-009-5293

Brush, artist, small NSN 8020-00-262-9098

Brush, artist, med NSN 8020-00-224-8026

Brush, nylon PN 375 HP, Gordon Brush Co.

Brush, stainless steel PN 22SSA, Gordon Brush Co.

Burnisher, J, no. 27 NSN 6520-00-510-8150

Carver, dental, no. 1/2 NSN 6520-00-935-7171

Carver, dental, no. 3 NSN 6520-00-511-5450

Carver, dental, no. 5T NSN 6520-00-935-7252

Carver, dental, no. 6T NSN 6520-01-016-3690

Carver, dental, Roach NSN 6520-00-511-5550

Chisel, Black, no. 48 NSN 6520-00-514-7050

Chisel, Black, no. 84 NSN 6520-00-536-4025 *NSL: Not stock listed.

Chisel, dental, Chandler, no. 1 NSN 6520-01-006-9343

Chisel, dental, Chandler, no. 4 NSN 6520-01-006-9344

Chisel, dental, Gardner, no. 5 NSN 6520-01-006-9345

Chisel, dental, no. 2 NSN 6520-01-047-3586

Chisel, dental, no. 41 NSN 6520-00-515-1050

Chisel, dental, no. 42 NSN 6520-00-515-1550

Chisel, 1/2 inch NSN 5110-00-234-1927

Cooler, Component Pneumatic Model #5810 (0ECV7)

Cutters, end, full flush NSN 5110-P36-272

Cutters, diag, full flush 5110-P36-277

Cutters, diag, semi flush 5110-P36-275S

Cutters, diag, 6-inch NSN 5110-00-239-8253

Cutters, offset, oblique, 20 degree 5110-P36-274

Cutters, wire PN 42, AN-B-5316, Utica

Desoldering kit:

tip, desoldering NSN 3439-01-057-1002 tip, desoldering NSN 3439-01-078-8351 tip, desoldering NSN 3439-01-065-9650 tip, desoldering NSN 3439-00-134-9201 tip, desoldering NSN 3439-01-078-8351

Desoldering system NSL

Drill, dental, with handpieces no. 77 and no. IMP-88D NSL

Drill, twist, no. 44 NSN 5133-00-189-9289

Drill, twist, no. 51 NSN 5133-00-189-9296

Drill, twist, no. 52 NSN 5133-00-189-9297

Drill, twist, no. 55 NSN 5133-00-189-9300

1-2

Drill, twist, no. 68 NSN 5133-00-266-9228

Drill, twist, no. 75 NSN 5133-00-266-9247

File, half round, 8 in. NSN 5110-00-241-9147

File, needle, set of 12 NSN 5110-00-204-2685

Flashlight, penlight Local purchase

Flux dispenser NSL

Glass, magnifier with handle NSN 6650-00-514-3531

Grinding kit:

burr, cylinder, no. 57, HP NSL burr, cylinder, no. 59, HP NSL burr, cylinder, no. 556, HP NSL burr, cylinder, no. 556, RA NSL burr, cylinder, no. 558, HP NSN 6520-01-003-2259 burr, cylinder, no. 558, RA NSN 6520-01-003-2426 burr, cylinder, no. 560, HP NSL burr, cylinder, no. 560, RA NSL burr, cylinder, no. 1557, RA NSL burr, cylinder, no. 1557, HP NSL burr, cylinder, no. 1559, HP NSL burr, cylinder, no. 1559, RA NSL burr, dental trim, pear shaped NSN 6520-01-027-0345 burr, dental trim, round NSL burr, end cutting, no. 901, RA NSL burr, end cutting, no. 957, RA NSN 6520-00-000-0064 burr, end cutting, no. 957, HP NSL burr, end cutting, no. 958, RA NSL burr, in. cn, no. 33 1/2, HP NSN 6520-01-003-3133 burr, in. cn, no. 35, HP NSN 6520-00-721-6291 burr, in. cn, no. 35, RA NSN 6520-01-003-2272 burr, in. cn, no. 37, HP NSN 6520-00-721-6292 burr, in. cn, no. 37, RA NSN 6520-01-003-5346 burr, in. cn, no. 39, RA NSL burr, pear shaped, no. 330, RA NSL burr, pear shaped, no. 332, RA NSL burr, round, no. 1/2, HP NSN 6520-01-003-3132 burr, round, no. 1/2, RA NSN 6520-01-049-0422 burr, round, no. 2, HP NSN 6520-01-003-2269 burr, round, no. 2, RA NSN 6520-01-003-2274 burr, round, no. 4, HP NSN 6520-01-003-2270 burr, round, no. 4, RA NSN 6520-01-003-2275 burr, round, no. 6, HP NSN 6520-00-721-6296 burr, round, no. 6, RA NSN 6520-01-003-7703 burr, round, no. 8, HP NSN 6520-01-003-3131 burr, round, no. 8, RA NSN 6520-01-003-2276 burrs, with case PN 3200 mandrel, screw type, HP NSN 6520-00-926-8846 mandrel, screw type, RA NSN 6520-00-926-8845 mandrel, no. 303 1/2 NSN 6520-01-060-1667

Hammer, ball-peen, 4 oz NSN 5120-00-061-8540

1-3

Handle, scalpel, no. 3 NSN 6515-00-344-7800

Handle, scalpel, no. 4 NSN 6515-00-344-7820

Handle, scalpel, no. 9 NSN 6515-00-344-7920

Holder, circuit card NSL

Holder, device, electrical NSN 5120-00-330-7602

Hypodermic needle NSN 6516-00-754-2837

Hypodermic syringe, 2 cc NSN 6516-00-889-3564

Knife/pin vise, with tools NSN 5110-00-175-3629

Lead bender NSN 5120P-176-BOU1

Machining unit, miniature NSN 4940-00-495-4489

Magnifier, bench mount NSN 6650-00-801-1681

Microscope illuminator NSN 6650-00-578-6543

Microscope, stereo, zoom NSN 6650-00-945-3098

Wrench set, socket NSN 5120-00-089-3663

Soldering aid tool NSN 3439-00-174-7846

Soldering aid tool NSN 3439-00-174-7847

Pick, dental, straight NSN 3439-PSH-1116

Pliers, common NSN 5170-00-223-7396

Pliers, crimping NSN 5120-00-446-8255

Pliers, long nose, 60 degrees,…