RACAL AN-GRC-238 User manual

TO 31R2-2GRC238-1

OPERATION AND MAINTENANCE INSTRUCTIONS

WITH ILLUSTRATED PARTS BREAKDOWN

ORGANIZATIONAL LEVEL

RADIO SET, AN/GRC-238

(BASE STATION)

RACAL COMMUNICATIONS, INC.

5 RESEARCH PLACE

ROCKVILLE, MD 20850

CONTRACT NO: F19628-91-D-0012

DISTRIBUTION STATEMENT B - Distribution authorized to U.S. Government agencies only for administrative or operational use, 15 June, 1993. Other requests for this document shall be referred to Sacramento ALC/TILBE, 3200 Peacekeeper Way, Suite 1, McClellan AFB, CA 95652-1026.

WARNING - This document contains technical data whose export is restricted by the Arms Export Control Act (Title 22, U.S.C., Sec 2751 et seq.) or the Export Administration Act of 1979, as amended (Title 50, U.S.C., App 2401 et seq.). Violations of these export laws are subject to severe criminal penalties.

HANDLING AND DESTRUCTION NOTICE - Handle in compliance with distribution statement and destroy by any method that will prevent disclosure of contents or reconstruction of the document.

PUBLISHED UNDER AUTHORITY OF THE SECRETARY OF THE AIR FORCE

15 JUNE 1993

CHANGE 5 - 20 NOVEMBER 1998

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TABLE OF CONTENTS

Chapter Page

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

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

SAFETY SUMMARY...............................................................................................................................................

FOREWORD.............................................................................................................................................................

CHAPTER 1 GENERAL INFORMATION ...........................................................................................................1-3

1-1 DESCRIPTION AND PURPOSE. ..............................................................................................................1-3

1-1.1 Equipment Function and Purpose........................................................................................................1-3

1-1.2 Equipment Description. .......................................................................................................................1-3

1-2 LEADING PARTICULARS. ......................................................................................................................1-8

1-3 CAPABILITIES AND LIMITATIONS. .....................................................................................................1-9

1-4 EQUIPMENT SUPPLIED.........................................................................................................................1-10

1-5 EQUIPMENT REQUIRED BUT NOT SUPPLIED..................................................................................1-10

1-6 SPECIAL TOOLS AND TEST EQUIPMENT. ........................................................................................1-10

1-7 RELATED TECHNICAL MANUALS.....................................................................................................1-11

CHAPTER 2 INSTALLATION ...............................................................................................................................2-1

2-1 INTRODUCTION. ......................................................................................................................................2-1

ECTION

I. INSTALLATION LOGISTICS............................................................................................................2-1

2-2 SITE PREPARATION. ...............................................................................................................................2-1

2-3 UNPACKING AND INSPECTIONS..........................................................................................................2-1

2-4 HOUSING. ..................................................................................................................................................2-3

2-5 RECEIVING DATA....................................................................................................................................2-3

2-6 MATERIAL HANDLING........................................................................................................................... 2-4

2-7 CABLES...................................................................................................................................................... 2-4

2-8 BUILDINGS AND OTHER SUPPORTING STRUCTURES. ...................................................................2-4

ECTION

2-9 TOOLS AND EQUIPMENT REQUIRED FOR

II. INSTALLATION PROCEDURES .....................................................................................................2-5

FIELD INSTALLATION. ..............................................2-5

2-9.1 Tools. ...................................................................................................................................................2-5

2-9.2 Equipment............................................................................................................................................2-5

2-10 INSTALLATION SEQUENCE...................................................................................................................2-5

2-10.1 General.................................................................................................................................................2-5

2-10.2 Antenna/Mast Installation....................................................................................................................2-7

2-10.3 Alternate Antenna/Mast Mounting. ...................................................................................................2-11

2-10.4 Installing Base Station Unit. ..............................................................................................................2-13

2-10.5 Installing Power Supply Assembly....................................................................................................2-13

2-10.6 Installing External Loudspeaker. .......................................................................................................2-13

2-10.7 Raising Base Station Operator Panel. ................................................................................................ 2-13

2-10.8 Installing Main Receiver-Transmitter................................................................................................ 2-14

2-10.9 Installing Guard Receiver-Transmitter. .............................................................................................2-14

2-10.10 Electrical Connections. ......................................................................................................................2-14

CHAPTER 3 PREPARATION FOR USE AND RESHIPMENT .........................................................................3-1

3-1 INTRODUCTION. ......................................................................................................................................3-1

ECTION

I. PREPARATION FOR USE..................................................................................................................3-1

3-2 INSPECTION..............................................................................................................................................3-1

3-3 POST-INSTALLATION CHECKOUT.......................................................................................................3-1

3-3.1 Preliminary. .........................................................................................................................................3-1

3-3.2 Alignment and Adjustment..................................................................................................................3-1

3-3.3 Post-Installation Checkout Procedures. ............................................................................................... 3-1

ECTION

3-4 PREPARING

II. PREPARATION FOR RESHIPMENT............................................................................................... 3-1

UNIT FOR RESHIPMENT. .................................................................................................3-1

3-5 PACKING....................................................................................................................................................3-2

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3-6 HANDLING AND STORAGE................................................................................................................... 3-2

3-6.1 Protective Measures for Electrical Connectors. .................................................................................. 3-2

3-6.2 Preparation for Shipment and Storage................................................................................................. 3-2

3-6.3 Handling.............................................................................................................................................. 3-2

CHAPTER 4 OPERATION..................................................................................................................................... 4-1

ECTION

I. CONTROLS AND INDICATORS...................................................................................................... 4-1

4-1 INTRODUCTION....................................................................................................................................... 4-1

4-2 CONTROLS AND INDICATORS............................................................................................................. 4-1

4-2.1 Indicators............................................................................................................................................. 4-1

4-2.2 Front Panel Controls, Switches, and Connectors. ............................................................................... 4-1

4-2.3 Keypad. ............................................................................................................................................... 4-1

4-2.4 Rear Panel Connectors. ....................................................................................................................... 4-1

4-2.5 Battery Tray Controls and Connectors................................................................................................ 4-1

ECTION

II. OPERATING INSTRUCTIONS ...................................................................................................... 4-11

4-3 MODES OF OPERATION. ...................................................................................................................... 4-11

4-4 INITIAL POWER-UP............................................................................................................................... 4-11

4-5 NORMAL OPERATION (MODE 0)........................................................................................................ 4-12

4-5.1 Introduction....................................................................................................................................... 4-12

4-5.2 Select Radio (Receiver-Transmitter) and Mode................................................................................ 4-12

4-5.3 Operation of Receiver-Transmitters.................................................................................................. 4-13

4-5.4 Display Intensity Adjustment............................................................................................................ 4-16

4-6 MANUAL FREQUENCY ENTRY (MODE 1)........................................................................................ 4-16

4-7 CHANNEL ENTRY (MODE 2). .............................................................................................................. 4-17

4-8 DISPLAYING ACTIVE FAULTS (MODE 3)......................................................................................... 4-18

4-9 PROGRAMMING RADIO (MODE 4). ................................................................................................... 4-19

4-9.1 Description of Program Radio (Receiver-Transmitter) Mode........................................................... 4-19

4-9.2 Detailed Programming Instructions................................................................................................... 4-25

4-10 EQUIPMENT SHUT DOWN................................................................................................................... 4-38

ECTION

III. EMERGENCY OPERATION......................................................................................................... 4-38

4-11 ELECTROMAGNETIC PULSE PROTECTION..................................................................................... 4-38

4-11.1 EMP Susceptibility............................................................................................................................ 4-38

4-11.2 EMP Protective Measures. ................................................................................................................ 4-38

4-12 NUCLEAR, BIOLOGICAL, AND CHEMICAL (NBC) CONTAMINATION....................................... 4-38

4-13 EMERGENCY POWER. .......................................................................................................................... 4-38

CHAPTER 5 THEORY OF OPERATION ............................................................................................................ 5-1

ECTION

I. FUNCTIONAL SYSTEM(S) OPERATION ....................................................................................... 5-1

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

5-2 FUNCTIONAL SYSTEM(S) OPERATION. ............................................................................................. 5-1

5-2.1 Main and Guard Receiver-Transmitters. ............................................................................................. 5-1

5-2.2 Antenna System................................................................................................................................... 5-3

5-2.3 Reference Oscillator Circuit Card Assembly (CCA) (A1). ................................................................. 5-3

5-2.4 Control Interface Circuit Card Assembly (CCA) (A2)........................................................................ 5-3

5-2.5 Audio Interface Circuit Card Assembly (CCA) (A3).......................................................................... 5-3

5-2.6 Parent Circuit Card Assembly (CCA) (A4)......................................................................................... 5-3

5-2.7 Control Panel Assembly (A5). ............................................................................................................ 5-3

5-2.8 Power Amplifier Assembly (A6). ....................................................................................................... 5-3

5-2.9 Harmonic Filter Assembly (A7).......................................................................................................... 5-4

5-2.10 Operator Panel Assembly (A12). ........................................................................................................ 5-4

5-2.11 Base Station Power Supply. ................................................................................................................ 5-4

5-2.12 Primary Battery Tray........................................................................................................................... 5-4

5-2.13 External Loudspeaker.......................................................................................................................... 5-4

5-2.14 Hand Microphone................................................................................................................................ 5-4

5-2.15 Headset with Boom Microphone......................................................................................................... 5-4

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ECTION

II. FUNCTIONAL OPERATION OF ELECTRONIC CIRCUITS .........................................................5-6

5-3 REFERENCE OSCILLATOR CIRCUIT CARD ASSEMBLY (CAA) (A1). ............................................5-6

5-4 CONTROL INTERFACE CIRCUIT CARD ASSEMBLY (CCA) (A2). ................................................... 5-6

5-4.1 System Interfaces................................................................................................................................. 5-6

5-5 AUDIO INTERFACE CIRCUIT CARD ASSEMBLY ............................................................................5-10

5-6 60 WATT POWER AMPLIFIER ASSEMBLY (A6). ..............................................................................5-10

5-7 HARMONIC FILTER ASSEMBLY (A7). ...............................................................................................5-10

5-8 OPERATOR PANEL CCA (A12A1)........................................................................................................5-10

ECTION

III. FUNCTIONAL OPERATION OF MECHANICAL ASSEMBLIES..............................................5-10

CHAPTER 6 MAINTENANCE ...............................................................................................................................6-1

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

6-2 OPERATIONAL CHECKOUT...................................................................................................................6-1

6-2.1 Base Station Test Mode. ...................................................................................................................... 6-1

6-2.2 Power-Up Verification.........................................................................................................................6-2

6-2.3 Display Brightness Control..................................................................................................................6-2

6-2.4 Channel and Frequency Settings Check...............................................................................................6-3

6-3 SERVICING................................................................................................................................................6-3

6-3.1 Servicing Intervals. ..............................................................................................................................6-3

6-3.2 Inspection.............................................................................................................................................6-3

6-3.3 Preventive Maintenance.......................................................................................................................6-3

6-4 TROUBLESHOOTING...............................................................................................................................6-4

6-5 REMOVAL/REPLACEMENT PROCEDURES.......................................................................................6-10

6-5.1 Removal/Replacement Procedures - Operator...................................................................................6-10

6-5.2 Removal/Replacement Procedures - Repair Specialist......................................................................6-11

CHAPTER 7 ILLUSTRATED PARTS BREAKDOWN .......................................................................................7-1

SECTION I. INTRODUCTION.............................................................................................................................7-1

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

7-2 MAINTENANCE PARTS LIST. ................................................................................................................7-1

7-3 NUMERICAL INDEX. ...............................................................................................................................7-2

7-4 REFERENCE DESIGNATION INDEX. ....................................................................................................7-3

7-5 ELECTROSTATIC DISCHARGE (ESD) SENSITIVE DEVICES............................................................7-3

7-6 CAGE CODE SUMMARY. ........................................................................................................................ 7-4

ECTION

II. MAINTENANCE PARTS LISTS....................................................................................................... 7-9

III. NUMERICAL INDEX.....................................................................................................................7-20

IV. REFERENCE DESIGNATION INDEX .........................................................................................7-22

V. COMMON BULK ITEMS LIST ......................................................................................................7-23

CHAPTER 8 CIRCUIT DIAGRAMS .....................................................................................................................8-1

8-1 SCOPE.........................................................................................................................................................8-1

GLOSSARY

ALPHABETICAL INDEX

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LIST OF ILLUSTRATIONS

Page

Figure 1-1. Radio Set AN/GRC-238.......................................................................................................................... 1-0

Figure 1-2. Receiver-Transmitter Set RT-1696/U(C)................................................................................................ 1-4

Figure 1-3. Antenna System....................................................................................................................................... 1-5

Figure 1-4. Power Supply Assembly.......................................................................................................................... 1-5

Figure 1-5. External Loudspeaker.............................................................................................................................. 1-6

Figure 1-6. Dynamic Microphone.............................................................................................................................. 1-6

Figure 1-7. Headset with Boom Microphone............................................................................................................. 1-7

Figure 1-8. Primary Battery Tray Assembly .............................................................................................................. 1-7

Figure 2-1. Packaging Diagram for the Base Station................................................................................................. 2-2

Figure 2-2. Antenna Mast.Antenna Installation - Step 1 of 7 .................................................................................... 2-7

Figure 2-3. Antenna Mast/Antenna Installation - Step 2 of 7 .................................................................................... 2-8

Figure 2-4. Antenna Mast/Antenna Installation - Step 3 of 7 .................................................................................... 2-8

Figure 2-5. Antenna Mast/Antenna Installation - Step 4 of 7 .................................................................................... 2-8

Figure 2-6. Antenna Mast/Antenna Installation - Step 5 of 7 .................................................................................... 2-9

Figure 2-7. Antenna Mast/Antenna Installation - Step 6 of 7 .................................................................................... 2-9

Figure 2-8. Antenna Mast/Antenna Installation - Step 7 of 7 .................................................................................. 2-10

Figure 2-9 Roof Mounting ....................................................................................................................................... 2-11

Figure 2-10. Tripod Mounting ................................................................................................................................. 2-12

Figure 2-11. Side of Building Mounting.................................................................................................................. 2-12

Figure 4-1. Location of Base Station Indicators......................................................................................................... 4-2

Figure 4-2. Location of Front Panel Controls, Switches and Connectors .................................................................. 4-4

Figure 4-3. Base Station Keypad................................................................................................................................ 4-7

Figure 4-4. Location of Rear Panel Connectors......................................................................................................... 4-9

Figure 4-5. Battery Tray Switch and Connectors..................................................................................................... 4-10

Figure 4-6. Available Menus.................................................................................................................................... 4-24

Figure 5-1. Base Station Block Diagram.................................................................................................................... 5-2

Figure 5-2. Reference Oscillator CCA (A1), Functional Block Diagram.................................................................. 5-5

Figure 5-3. System Interface Diagram....................................................................................................................... 5-7

Figure 5-4. Audio Interface CCA (A3), Functional Block Diagram.......................................................................... 5-9

Figure 5-5. 60 Watt Power Amplifier Assembly (A6), Functional Block Diagram................................................. 5-11

Figure 5-6. Harmonic Filter Assembly (A7), Functional Block Diagram................................................................ 5-12

Figure 5-7. Operator Panel CCA (A12A1), Functional Block Diagram .................................................................. 5-13

Figure 7-1. Radio Set AN/GRC-238.......................................................................................................................... 7-8

Figure 7-2. Base Station Assembly (SS-4100804-501) (Sheet 1 of 2)..................................................................... 7-12

Figure 7-3. Power AMP Assy, 60W (SS-4100852-501).......................................................................................... 7-18

FO-1 Radio Set AN/GRC-238, Interconnection Diagram......................................................................... FP-1

FO-2 Control Interface CCA, Block Diagram........................................................................................... FP-3

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LIST OF TABLES

Page

Table 1-1. Receiver-Transmitter Configurations Vs Frequency Band .......................................................................1-4

Table 1-2. Leading Particulars.................................................................................................................................... 1-8

Table 1-3. Capabilities and Limitations......................................................................................................................1-9

Table 1-4. Equipment Supplied ................................................................................................................................1-10

Table 1-5. Related Technical Manuals .....................................................................................................................1-11

Table 2-1. Base Station Packaging .............................................................................................................................2-3

Table 2-2. Base Station Interconnecting Cables.........................................................................................................2-4

Table 2-3. Base Station Tools.....................................................................................................................................2-5

Table 4-1. Description of Operator Indicators............................................................................................................4-3

Table 4-2. Description of Front Panel Operator Controls, Switches and Connectors.................................................4-5

Table 4-3. Description of Keypad Keys .....................................................................................................................4-8

Table 4-4. Description of Rear Panel Connectors.......................................................................................................4-9

Table 4-5. Primary Battery Tray Switch and Connectors.........................................................................................4-10

Table 4-6. Select Radio (Receiver-Transmitter) and Mode......................................................................................4-13

Table 4-7. Manual Frequency Entry (Mode 1).........................................................................................................4-16

Table 4-8. Channel Entry (Mode 2)..........................................................................................................................4-17

Table 4-9. Displaying Active Faults (Mode 3).........................................................................................................4-18

Table 4-10. Base Station Programming Requirements Matrix .................................................................................4-20

Table 4-11. Programmable Features.........................................................................................................................4-21

Table 4-12. Program Channel................................................................................................................................... 4-26

Table 4-13. RX Frequency........................................................................................................................................4-27

Table 4-14. TX Frequency........................................................................................................................................4-28

Table 4-15. RX Tone................................................................................................................................................4-29

Table 4-16. TX Tone ................................................................................................................................................4-30

Table 4-17. RF Power...............................................................................................................................................4-31

Table 4-18. RX IF Bandwidth ..................................................................................................................................4-32

Table 4-19. Secure Data Rate ................................................................................................................................... 4-33

Table 4-20. Programming Options ...........................................................................................................................4-34

Table 4-21. Zeroize Receiver-Transmitter................................................................................................................4-36

Table 4-22. Cloning Receiver-Transmitters .............................................................................................................4-37

Table 6-1. Initial Switch and Control Settings for Operational Checkout..................................................................6-1

Table 6-2. Recommended Service Intervals...............................................................................................................6-3

Table 6-3. Base Station Fault Messages .................................................................................................................... 6-5

Table 6-4. Organizational Maintenance Guide - Operator .........................................................................................6-6

Table 6-5. Organizational Maintenance Guide - Repair Specialist.............................................................................6-8

Table 6-6. Cross-Reference to Removal/Replacement Procedures ..........................................................................6-10

Table 7-1. Radio Set AN/GRC-238............................................................................................................................7-9

Table 7-2 Base Station Assembly (SS-4100804-501) ..............................................................................................7-14

Table 7-3. Power AMP Assy, 60W (SS-4100852-501)............................................................................................7-19

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SAFETY SUMMARY

The following are general safety precautions that are not related to any specific procedure, and do not appear elsewhere in this manual. These Safety Summaries are recommended precautions that all personnel must understand and apply during any given phase of operation and maintenance. Each chapter has other specific warnings and cautions.

WARNING

KEEP AWAY FROM LIVE CIRCUITS

Personnel must at all times observe all safety regulations. Do not replace components or make adjustments inside equipment with power turned on. Under certain conditions, dangerous voltages may exist when the power control is in the off position due to charges retained by capacitors. To avoid injury, always remove power and discharge and ground a circuit before touching it.

RESUSCITATION

Personnel working with or near high voltages should be familiar with modern methods of resuscitation. Such information may be obtained from the Director of Base Medical Services.

WARNING

VOLTAGES WITHIN THIS EQUIPMENT ARE HIGH ENOUGH TO ENDANGER LIFE.

Covers are persons should always take extreme care once the covers have been removed.

to be removed except by persons qualified and authorized to do so and these

not

TO 31R2-2GRC238-1

WARNING

LITHIUM BATTERIES

Lithium oxide batteries or cells may be used to provide portable power for this equipment. They are potentially hazardous if misused or tampered with before, during or after discharge. The following precautions must be strictly observed to prevent possible injury to personnel or equipment damage.

heat, incinerate, crush, puncture, disassemble, or otherwise mutilate the batteries.

Do not

Do not short-circuit, recharge, or bypass internal fuse.

Do not store batteries in equipment during long periods of non-use (in excess of 30 days).

Turn off the equipment immediately if you detect battery compartment becoming unduly hot, hear battery cells

venting (hissing sounds), or smell irritating sulfur dioxide gas.

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Page

2-9 WARNING - Before using hammer, place a wedge in top of hammer to ensure that head of hammer does not

come loose.

3-2 WARNING - Before performing removal/replacement procedures, make sure power is removed from the unit.

Failure to do so could result in personal injury or damage to the equipment.

6-11 WARNING - Before performing removal/replacement procedures, make sure power is removed from the unit.

Failure to do so could result in personal injury or damage to the equipment.

2-1 CAUTION - Exercise care when removing assemblies from packing material in order to prevent damage to the

unit.

2-7 CAUTION - Ensure proper use of safety tools (work gloves and hard hat) during assembly and disassembly of

antenna.

3-2 CAUTION - Never apply pressure sensitive tape directly to connectors. This could damage connector pins.

3-2 CAUTION - Package all electrostatic discharge (ESD) sensitive assemblies in ESD bags before shipping or

storing.

3-3 CAUTION - Rough handling can cause damage to electronic assemblies.

3-3 CAUTION - Electronic assemblies containing solid-state devices are susceptible to damage from static electrical

discharges. Wear protective clothing and grounded wrist straps.

3-3 CAUTION - Forcing any misaligned electronic assembly into position may result in bent or broken pins.

3-3 CAUTION - Be very careful when removing or inserting an assembly into the equipment. If it is a plug-in CCA,

be sure the guide pins are properly aligned before pressing the assembly in place. If the CCA tilts while being inserted, do not continue to press into position; straighten it, then apply even pressure to avoid tilting.

3-3 CAUTION - When repairing an electronic assembly, be careful that the tool employed does not inadvertently

press against leads, pins, or other parts that are easily bent. Such pressure can destroy a good part and cause needless repair.

3-3 CAUTION - When handling an assembly that has been removed from its chassis, be careful not to press against

the leads and pins. When removing an assembly, be sure to pull it straight out from the equipment. Do not cock, twist, pry, or jerk an electronic assembly to remove it from the mounting connector.

3-3 CAUTION - The base station contains components that are susceptible to damage by static electrical charges.

Disassembly of the base station should only be done at a properly grounded work station.

6-11 CAUTION - The base station contains CCAs and components that are susceptible to damage by electrostatic

discharge (ESD). Disassembly of the base station should only be done at a properly grounded work station. Use ESD precautionary procedures (wear grounding wrist straps) when touching, removing, and installing the modules.

6-11 CAUTION - Use care in removing and replacing CCAs to prevent damage to pins and sockets.

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FOREWORD

This manual meets the technical content requirements of specification MIL-M-38798B, paragraph 3.3 (1 December 1975) and MIL-M-38807A (1 June 1982) and format requirements of specification MIL-M-38784B (16 April 1983) for Radio Set AN/GRC-238, commonly known as the base station.

a. Chapter 1 - General Information. This chapter provides general information for the base station

including equipment description and purpose, leading particulars, capabilities and limitations, equipment supplied, equipment required but not supplied, optional equipment, special tools and test equipment, and related technical manuals.

b. Chapter 2 - Installation. This chapter provides complete installation instructions for the base station

including installation logistics and installation procedure.

c. Chapter 3 - Preparation for Use and Reshipment. This chapter contains information which will permit

operation and maintenance personnel to prepare the equipment for use, including reference to postinstallation checkout procedures, preparing the unit for reshipment, packing, handling, and storage procedures.

d. Chapter 4 - Operation. This chapter provides complete operating instructions for the base station.

e. Chapter 5 - Theory of Operation. This chapter provides complete theory of operation for the base

station.

f. Chapter 6 - Maintenance. This chapter provides all instructions required for on-equipment and off-

equipment maintenance of the base station. Includes preventive maintenance procedures, troubleshooting procedures, and repair procedures.

g. Chapter 7 - Illustrated Parts Breakdown (IPB). Provides complete illustrated parts breakdown for the

base station. The IPB prepared in accordance with MIL-M-38807A.

h. Chapter 8 - Circuit Diagrams. Contains interconnection diagrams and block diagrams.

i. Glossary - Provides definitions of the special terms and abbreviations used in the technical order.

j. Alphabetical Index - Provides cross-references to applicable paragraphs, figures or tables.

TO 31R2-2GRC238-1

Legend for Figure 1-1:

1. Antenna, 30-88 MHz

2. Mast, Antenna, Base Station

3. Antenna, 136-174 MHz

4. Antenna, 403-470 MHz

5. Cable Assembly, Power Supply, 120 VAC (W1)

6. Cable Assembly, Power Supply, 240 VAC (W1)

7. Cable Assembly, Power Supply DC Input (W1)

8. Power Supply, Base Station

9. Cable Assembly, BS Power (W2)

10. Strap Assembly, Ground (W6)

11. Loudspeaker, External (U1810) TD 708/WP

12. Cable Assembly, Coaxial, Antenna (W3)(W4)

13. Headset w/Boom Microphone

14. Microphone, Dynamic

15. Receiver-Transmitter Set, Radio RT-1696/U(C)

16. Cable, Jumper

17. Base station unit

18. Primary Battery Tray

Cable Assembly, Programming (W5) (Not illustrated)

1-0

Figure 1-1. Radio Set AN/GRC-238

(Sheet 1 of 2)

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Figure 1-1. Radio Set AN/GRC-238

(Sheet 2 of 2)

1-1/(1-2 blank)

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CHAPTER 1 GENERAL INFOR MATION

1-1 DESCRIPTION AND PURPOSE.

1-1.1 Equipment Function and Purpose.

Radio Set AN/GRC-238 (hereinafter referred to as the base station) is a multi-voltage frequency modulation (FM) receiver-transmitter that can transmit on one channel while simultaneously monitoring a second channel. The base station is capable of providing two-way (transmit and receive) communication in the 30-88, 136-174, or 403-470 Megahertz (MHz) frequency bands. Communication can be in either secure or non-secure modes. The base station uses analog FM in the non-secure mode and encrypted digitized voice FM in the secure mode.

The ability of the base station to transmit while simultaneously monitoring a guard channel is provided by two RT-1696/U(C) Receiver-Transmitter Set, Radios (hereinafter referred to as the receiver-transmitters). The base station is interoperable with other receiver-transmitters including the AN/PRC-77 Manpack Radio, Radio Set AN/PRC-128, and very high frequency (VHF) FM single channel mode of the SINCGARS-V. The base station also provides compatibility with FED-STD-1023, 12 kilobits/second (kbps) receiver-transmitters. For operation and maintenance information for Receiver-Transmitter Set, Radio RT-1696/U(C) refer to TO 31R2-2PRC139-1.

1-1.2 Equipment Description.

(See Figure 1-1.) The base station includes a base station unit, two plug-in receiver-transmitters and two mast-mounted antennas (one for main and one for guard) for each frequency band, a power supply assembly, various audio assemblies (microphone, headset, loudspeaker), a primary battery tray, and several cable assemblies. The base station can be installed in any building or structure meeting the electrical power and environmental requirements specified in Table 1-2 and allowing for placement of antennas to provide unobstructed radio propagation paths to all remote locations with which communication is required. These items are covered in more detail in paragraphs 1-1.2.1 through 1-1.2.6 below.

1-1.2.1 Base Station Unit.

(See Figure 7-2.) The base station unit includes three circuit card assemblies (CCAs) which are accessible through a removable cover on the underside of the unit - the reference oscillator CCA (A1) (45), the control interface CCA (A2) (44), and the audio interface CCA (A3) (43). These CCAs plug into a parent board (A4) (50) which interfaces with control panel assembly (A5) (5), power amplifier assembly (A6) (19), harmonic filter assembly (A7) (30), operator panel (A12) (52), the base station power supply assembly (8, Figure 7-1), and two plug-in receiver-transmitters (15, Figure 7-1). The receiver-transmitters plug into sleeves located on the left and right side of the control panel of the base station unit. The power amplifier (A6) (19) mounts on a heat sink on top of the unit. The operator panel is hinged so that it can be closed and latched when the unit is not in use.

1-1.2.2 Receiver-Transmitters.

(See Figure 1-2.) The two plug-in receiver-transmitters included with the base station are the same receiver-transmitters used by Radio Set AN/PRC-139(C). One receiver-transmitter provides the operator with a primary channel for routine traffic. This is referred to as the main receiver-transmitter. The other receiver-transmitter provides a guard or emergency use channel which constantly monitors for traffic on the tuned guard channel. This is referred to as the guard receivertransmitter. Each receiver-transmitter includes three interchangeable transceiver modules and a hand-held radio chassis. Use of the interchangeable transceiver modules provides the capability of operating at all frequencies within the 30-88, 136-174, or 403-470 MHz frequency bands. The operating band of the receiver-transmitter is determined by the transceiver module installed. The transceiver module is enclosed within the rear cover assembly of the receivertransmitter. When the transceiver modules are changed, the base station must be connected to the corresponding antenna. The proper configurations are listed in Table 1-1.

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Frequency Band Receiver-Transmitter Transceiver Module Antenna

30-88 MHz SS-4100820-501 4242-MK2-RAC

136-174 MHz SS-4100821-501 4265-RAC

403-470 MHz SS-4100822-501 4266-RAC

Table 1-1. Receiver-Transmitter Configurations Vs Frequency Band

Legend for Figure 1-2:

1. 2, 3. Transceiver module

4. Hand-held radio chassis

Figure 1-1Figure 1-2. Receiver-Transmitter Set RT-1696/U(C)

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1-1.2.3 Antenna Assembly.

(See Figure 1-3.) The antenna assembly provides full-duplex transmit and receive frequency coverage over the three frequency bands. Six antennas are provided to cover the three frequency bands, two antennas for each of the three frequency bands.

Figure 1-3. Antenna System

Masts are supplied with the antennas to elevate the antennas up to 30 feet (in 5 foot increments) to increase transmission range and quality of transmitted and received signals.

1-1.2.4 Power Supply Assembly.

(See Figure 1-4.) The power supply provides regulated power for the operation of the base station. The power supply operates from any of the following power sources:

a. 120/240 VAC "10% (single phase, three wire) 50-60 Hz b. 220 VAC "10% (single phase, two wire) 50 Hz c. 12 VDC (+4V/-2V) d. 24 VDC (+8V/-4V)

Figure 1-4. Power Supply Assembly

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TO 31R2-2GRC238-1

1-1.2.5 Audio Accessories.

The operator has the option of several handsets/headsets and an external loudspeaker (see Figure 1-5). The internal or external loudspeaker provides audio output for guard and main receive signals originating from the receiver-transmitter. A dynamic microphone (SS-3100520-501) (see Figure 1-6) requires that either the internal or external loudspeaker be used with the base station. A headset with boom microphone (see Figure 1-7) allows the operator to more effectively operate the equipment in a noisy environment or to turn off both the internal and external loudspeaker (using the speaker switch) for more covert operation. The boom microphone reduces noise. Transmission control is via a push-to-talk (PTT) switch that is located on a belt-worn control box. The dynamic microphone and the headset are provided with cable assemblies, one of which can be connected to the HEADSET connector on the base station at any one time. The external loudspeaker is provided with a cable assembly that connects to the EXT SPKR connector on the rear panel of the base station.

Figure 1-5. External Loudspeaker

Figure 1-6. Dynamic Microphone

Change 11-6

Figure 1-7. Headset with Boom Microphone

TO 31R2-2GRC238-1

1-1.2.6 Primary Battery Tray.

(See Figure 1-8) The base station includes a primary battery tray for operation in remote locations with no external power source. The tray consists of two battery holders with connectors in the bottom to hold a total of 12 BA-5590 lithium batteries. The connectors are mounted on an underlying circuit board that interconnects the batteries through an ON/OFF switch and 20 amp fuse to positive and negative terminals. The base station unit is connected to the battery tray using the DC power input cable (SS-4500106-501). The battery tray also has a grounding post.

Figure 1-8. Primary Battery Tray Assembly

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1-2 LEADING PARTICULARS.

Leading particulars for the base station are given in Table 1-2.

Table 1-2. Leading Particulars

Characteristic Parameter

Equipment dimensions and weight:

Base Station Unit

Length Width Height

Volume Weight (with radio installed)

Power Supply Assembly

14.50 inch (in.) (36.83 centimeters (cm))

10.00 in. (25.40 cm)

7.5 in. (19.05 cm) (operator panel closed)

12.0 in. (30.48 cm) (operator panel open) 1,087.5 cubic (cu) in. (17,821 cu cm)

26.5 lbs. (12.1 kilograms (kg))

Length Width Height Volume Weight

Environmental requirements:

Temperature:

Operating Storage

Humidity

Electrical power requirements:

DC source

AC source

12 in. (30.48 cm) 10 in. (25.40 cm) 3 in. (7.62 cm) 360 cu in. (5,899 cu cm)

9.75 lbs. (4.43 kg.)

0° Celsius (C) (32° Fahrenheit (F)) to +49°C (120°F)

-51°C (-60°F) to +68°C (155°F)

0 to 95 percent relative humidity

12 volts direct current (VDC) (-2 VDC, +4 VDC) or 24 VDC (-4 VDC, +8 VDC)

120/240 VAC " 10% (single phase, 3 wire) at 50-60

Hertz (Hz)

220 VAC (single phase, 2 wire) "10% at 50 Hz

1-8

1-3 CAPABILITIES AND LIMITATIONS.

Capabilities and limitations of the base station are given in Table 1-3.

Table 1-3. Capabilities and Limitations

Characteristic Parameter

Frequency Range (Main and Guard): 30-88 MHz

136-174 MHz 403-470 MHz

Transmitter Output 5, 16, and 40 watts selectable (main)

2 watts (guard)

Security TEMPEST compliant INDICTOR chip

Interoperability AN/PRC-77 Manpack radio

AN/PRC-128 hand-held radio SINCGARS-V (VHF-FM single channel radio)

12.5 kHz Bandwidth analog FM radios (clear mode only) 25 kHz Bandwidth analog FM radios (clear mode only) FED-STD-1023 compatible, 12 kbps VINSON (KY-57) compatible, 16 kbps

TO 31R2-2GRC238-1

Channels (receive and transmit) 14 channels individually programmable for main and for

guard

Channelization 25 kilohertz (kHz) bandwidth on all frequency bands

(secure transmission capable)

12.5 kHz bandwidth (non-secure only) on 136-174 MHz and 403-470 MHz bands

12.5 kHz tuning steps

Adjacent Channel Selectivity 50 decibels (dB) over 30-88 MHz, 25.0 kHz Bandwidth

52 dB over 136-174 MHz, 12.5 kHz Bandwidth 60 dB over 136-174 MHz, 25.0 kHz Bandwidth 40 dB over 403-470 MHz, 12.5 kHz Bandwidth 48 dB over 403-470 MHz, 25.0 kHz Bandwidth

Sensitivity -113 power in decibels (relative to 1 milliwatt) (dBm) or

0.5µV for 12 dB SINAD

Spurious Response and Image Rejection 65 dB over all three bands

Intermodulation Spurious Response 60 dB over all three bands

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TO 31R2-2GRC238-1

1-4 EQUIPMENT SUPPLIED.

Equipment supplied with the base station system is listed in Table 1-4.

Table 1-4. Equipment Supplied

Official Nomenclature Part Number Quantity

Base Station Unit SS-4100804-501 1

Receiver-Transmitter Set, Radio RT-1696/U(C) SS-4100807-502 2

Antenna, 30-88 MHz 4242-MK2-RAC 2

Antenna, 136-174 MHz 4265-RAC 2

Antenna, 403-470 MHz 4266-RAC 2

Mast, Antenna, Base Station SP30SS 2

Power Supply Assembly CPS3263 1

Headset w/Boom Microphone HS-711 SS 1

Microphone, Dynamic SS-3100520-501 1

Loudspeaker, External Z3344 1

Cable Assembly, Coaxial, Antenna CPRG214-100-UHF/VHF 2

Cable Assembly, Base Station Power SS-3500274-501 1

Cable Assembly, Programming SS-3500276-501 1

Strap Assembly, Ground SS-3500279-501 1

Cable Assembly, Power Supply, 120 VAC SS-4500104-501 1

Cable Assembly, Power Supply, 240 VAC SS-4500105-501 1

Cable Assembly, Power Supply Direct Current (DC) Input SS-4500106-501 1

Cable, Jumper SS-2500116-501 1

Primary Battery Tray SS-4100954-501 1

1-5 EQUIPMENT REQUIRED BUT NOT SUPPLIED.

All equipment required for operation of the base station is supplied.

1-6 SPECIAL TOOLS AND TEST EQUIPMENT.

There are no special tools or test equipment required for maintenance of the base station.

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1-7 RELATED TECHNICAL MANUALS.

Table 1-5 lists related technical manuals.

Table 1-5. Related Technical Manuals

Publication Number Publication Title

31R2-2PRC139-1 Operation and Maintenance Instructions with Illustrated Parts

Breakdown (Organizational Level) for Radio Set AN/PRC139(C) (includes Receiver-Transmitter RT-1695/TRC-199,

Receiver-Transmitter RT-1696/U (C), Programmer Unit,

Frequency, Radio MX-11531/U, Battery Chargers, and Battery Reconditioner)

31R2-2TRC199-1

31R2-4-1085-1 Operation and Maintenance Instructions with Illustrated Parts

31R2-2PRC139-06 Work Unit Code Manual

KAM-330 Operating Instructions for KOI-18 and KYK-13 COMSEC

ON477340 AN/CYZ-10 Data Transfer Device Users' Manual

Operation and Maintenance Instructions with Illustrated Parts Breakdown (Organizational Level) for Radio Set AN/TRC199

Breakdown (Organizational Level) for Adapter Group, Radio OF-228/U

Fill Devices

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TO 31R2-2GRC238-1

CHAPTER 2 INSTALLATION

2-1 INTRODUCTION.

This section is divided into two sections. Section I. Installation Logistics provides information for site preparation, unloading, unpacking and inspections, housing, receiving data, material handling, cabling required for installation into buildings and other supporting structures. Section II. Installation Procedures lists tools and equipment required for field installation and describes the installation sequence.

NOTE

CONTROLLED CRYPTOGRAPHIC ITEM

The receiver-transmitter used in the base station is a controlled cryptographic item (CCI). Consult your Communications Security (COMSEC) manager for security procedures.

Section I. INSTALLATION LOGISTICS

NOTE

Installation of the base station antennas requires a minimum of two people.

2-2 SITE PREPARATION.

The base station can be installed in any building or structure meeting the electrical power and environmental requirements specified in Table 1-2. However, antennas shall not be installed closer to power and telephone lines than two antenna lengths. Install main and guard antennas as far apart from each other as possible.

2-3 UNPACKING AND INSPECTIONS.

CAUTION

Exercise care when removing assemblies from packing material in order to prevent damage to the unit.

NOTE

The following procedure describes unpacking of the base station unit. The base station unit and other items of the base station are shipped in individual cutouts in a large foam-filled container.

To unpack the base station, remove the unit and any equipment from the carton and store the packing carton for reuse/shipment. Packing instructions are given in Chapter 3. Inspect contents for completeness, integrity, and damage. Contents shall be in accordance with the packing slip and the list of supplied equipment in Table 1-4.

Refer to Figure 2-1 as a guide in performing the following unpacking procedures:

a. Open the top of the fiberboard box (7, Figure 2-1) and remove the operating instructions (1) and

polystyrene top (2) from container.

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TO 31R2-2GRC238-1

2-2

Legend for Figure 2-1

1. Operator instructions 5. Barrier bag

2. Polystyrene top 6. Polystyrene bottom

3. Base station unit 7. Fiberboard box

4. Desiccant bag 8. Packing slip

Figure 2-1. Packaging Diagram for the Base Station

TO 31R2-2GRC238-1

b. Remove barrier bag (5) from the box.

c. Remove the base station unit (3) from foam insert. Remove remaining components from foam insert.

d. Remove packing slip (8) from the plastic envelope on the fiberboard box and check to ensure that all

items listed on the packing slip were received.

e. Store all packing materials (except desiccant) in shipping container and store shipping container for

re-use. Discard original desiccant. New desiccant material must be used when packing.

f. Inspect top and bottom, both sides, and front and rear panels of equipment for dents, scratches or any

visually identifiable damage.

g. Open the operator panel by releasing the latches on either side and pulling forward and up on the handle

(see Figure 1-1).

h. Inspect controls and indicators on front panel and operator panel for missing, broken or cracked knobs

or levers and note any discrepancies. Report any discrepancies using standard material reporting procedures.

2-4 HOUSING.

If necessary to store the base station for an extended period of time before installation, proceed as follows:

NOTE

COMMUNICATIONS SECURITY

Ensure that base station receiver-transmitters are zeroized (mode control switch on the receivertransmitter turned to Z position) before placing the base station in storage. This will ensure that the keys installed in the receiver-transmitters are not compromised.

a. Clean the base station before placing in storage. Refer to paragraph 6-3.3.2.

b. Disconnect antennas and accessories before placing the base station unit in storage.

c. Ensure that no COMSEC variables are present.

NOTE

The temperature of the storage area must be within the range -51EC (-60EF) to +68EC (155EF).

2-5 RECEIVING DATA.

Table 2-1 identifies the contents and particulars of the shipping container.

Table 2-1. Base Station Packaging

Dimensions (in)

Description

W H D

Weight(lb)

Radio Set AN/GRC-238 (Base Station) 32 29 70 245.0

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2-6 MATERIAL HANDLING.

No material handling equipment is required in the installation of the base station.

2-7 CABLES.

Table 2-2 lists all base station interconnecting cables. Refer to FO-1 for base station interconnect diagram.

Table 2-2. Base Station Interconnecting Cables

Cable

Designation

W1 SS-4500104-501 Cable Assembly, Power Supply, 120

W1 SS-4500105-501 Cable Assembly, Power Supply, 240

W1 SS-4500106-501 Cable Assembly, Power Supply, DC Connects base station to 10-32

W2 SS-3500274-501 Cable Assembly, Power Connects power supply DC output

W3 SS-1600290-1 Cable Assembly, Coaxial, Antenna Connects main antenna to base

W4 SS-1600290-1 Cable Assembly, Coaxial, Antenna Connects guard antenna to base

W5 SS-3500276-501 Cable Assembly, Programming Connects RS-232C input/output to

W6 SS-3500279-501 Strap Assembly, Ground Connects base station to external

W7 SS-2500116-501 Cable Jumper Connects two lead-acid 12 VDC

Cable Part No. Description Use

Connects base station to 120 VAC

volts alternating current (VAC) Input

Connects base station to 240 VAC

VAC Input

volts direct current (VDC)

to base station

station

the base station for receivertransmitter programming

ground

batteries in series for external DC power.

2-8 BUILDINGS AND OTHER SUPPORTING STRUCTURES.

Buildings or other structures in which the base station is to be installed must meet the electrical power and environmental requirements listed in Table 1-2. The area in which the base station is installed must be adequate to accommodate the open dimensions of the base station unit plus at least 6 inches of side clearance for cable connection. There should be space nearby for the power supply.

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+ 115 hidden pages

RACAL AN-GRC-238 User manual

Specifications and Main Features

Frequently Asked Questions

User Manual