TM 11 -5820 -1025 -10

RADIO SET AN/PRC-126

(NSN 5820-01-215-6181)

1 FEBRUARY 1988

Distribution authorized to the Department of Defense and DOD contractors onlyfor official use or for administration or operational purposes. This determination was made on 27 October 1987. Other requests for this document will bereferred to Commander, US Army Communications-Electronics Command andFort Monmouth, ATTN: AMSEL-ME-P, Fort Monmouth, NJ 07703-5000.

DESTRUCTION NOTICE – Destroy by any method that will prevent disclosure ofcontents or reconstruction of the document.

A lithium-sulfur dioxide (Li-SO2) battery used withthe AN/PRC-126 Radio Set contains pressurizedsulfur dioxide (SO2) gas. The gas is toxic, and thebattery MUST NOT be abused in any way whichmay cause the battery to rupture.

DO NOT heat, short circuit, crush, puncture,mutilate, or disassemble batteries.

DO NOT USE any battery which shows signs ofdamage, such as bulging, swelling, disfigurement,brown liquid in the plastic wrap, a swollen plasticwrap, etc.

DO NOT test Li-SO2 batteries for capacity.

DO NOT recharge Li-SO2 batteries.

If the battery compartment becomes hot to thetouch, if you hear a hissing sound (i.e., battery ven-ting), or smell irritating sulfur dioxide gas, IM-MEDIATELY Turn Off the equipment. Remove theequipment to a well ventilated area or leave thearea.

DO NOT use a Halon type fire extinguisher on alithium battery fire.

A

In the event of a fire, near a lithium battery (ies),rapid cooling of the battery (ies) is important. Usea carbon dioxide (CO2) extinguisher. Control of theequipment fire, and cooling, may prevent the bat-tery from venting and potentially exposing lithiummetal. In the event that lithium metal becomes in-volved in fire, the use of a graphite based Class Dfire extinguisher is recommended, such as Lith-Xor MET-L-X.

DO NOT use water to extinguish Li-SO2 batteryfires if a Shock hazard exists due to high voltageelectrical equipment in the immediate vicinity (i.e.,greater than 30 volts, alternating current (ac) ordirect current (dc)).

DO NOT store lithium batteries with other hazard-ous materials and keep them away from open flameor heat.

DO NOT store batteries in unused equipment formore than 30 days. Contact your local Fire Depart-ment for selection and approval of lithium batterystorage areas, and selection of appropriate fire ex-tinguishing equipment. Store lithium batteries in acool (i. e., less than 130 degrees F), dry, well ven-tilated area. For bulk storage use a sprinkler pro-tected area, and as a second choice store in a non-combustible area.

B

DO NOT dispose of lithium batteries with ordinarytrash/refuse. Turn in batteries to your local serv-ing Defense Reutilization and Marketing Office.

Only use batteries (items 1, 2 or 3, App. D) whichhave been authorized for this equipment.

Hold onto both RT unit and SVM when looseningsecuring screws.

Do not key transmitter with antenna connectorshorted out.

C

H O W T O U S E T H I S M A N U A L

This is a quick reference manual that hasbeen written just for you. Become familiarwith its contents so that you will be ableto find what you need quickly.

This manual will show you how to:

OPERATEMAINTAIN

YOUR RADIO SET AN/PRC-126

It is small enough to fit in your pocket soyou can always have it ready for quickreference. After you have had some timeto use it, take a moment to let us knowwhat you think about it.

D

TECHNICAL MANUALNo. 11-5820-1025-10 Headquarters,

Department of the ArmyWashington, DC, 1 February 1988

OPERATOR’S MANUALRADIO SET AN/PRC-126(NSN 5820-01-215-6181)

REPORTING ERRORS ANDRECOMMENDING IMPROVEMENTS

You can help improve this manual. If youfind any mistakes or if you know of a wayto improve the procedures please let usknow. Mail your letter or DA Form 2028-2directly to Commander, US Army Com-munications-Electronics Command and FortMonmouth, ATTN: AMSEL-ME-MP, FortMonmouth, New Jersey 07703-5000. Areply will be furnished to you.

i

Page

WARNINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . aHOW TO USE THIS MANUAL . . . . . . . d

CHAPTER 1 INTRODUCTION

Section I. General Information . . . . . . . . . . . . . 1-1

1-1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11-2 Maintenance Forms and

Records . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21-3 Reporting Equipment Improve-

ment Recommendations(EIR’s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

1-4 Warranty Information . . . . . . . . . . . . 1-3

Section II. ............ 1-3

1-5 Purpose and Use of Radio SetAN/PRC-126 . . . . . . . . . . . . . . . . . . . 1-3

1-6 Location and Description ofMajor Components . . . . . . . . . . 1-4

1-7 Equipment Data . . . . . . . . . . . . . . . . . . . 1-61-8 Assembly and Preparation

for Use . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

CHAPTER 2 OPERATING INSTRUCTIONS

Section I. Description and Use ofOperator’s Controls, andIndicators . . . . . . . . . . . . . . . . . . . . . . . 2-1

2-1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

i i

Page

2-2 Controls and Indicators . . . . . . . . . 2-1

Section II. Preventive MaintenanceChecks and Services . . . . . . . .

2-3 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-4 PMCS Procedures

ConditionsSection III. Operation Under Usual

2-5 Normal Operation . . . . . . . . . . . . . . . . .2-6 Channel Reprogramming . . . . . . .2-7 Battery Installation/

Removal . . . . . . . . . . . . . . . . . . . . . . . . . . .2-8 Secure Voice Module (SVM)

Installation andRemoval . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-9 Handset Installation/Removal . . . . . . . . . . . . . . . . . . . . . . . . ..

2-10 Antenna (Long or Short)Installation/Removal . . . . . . . . . . .

2-82-82-10

2-122-122-13

2-16

2-21

2-23

2-24

Section IV. Operation Under UnusualConditions . . . . . . . . . . . . . . . . . . . . . . 2-26

2-11 Operation at LowTemperatures . . . . . . . . . . . . . . . . . . 2-26

iii

Page

2-12 Operation at HighTemperatures . . . . . . . . . . . . . . . . . . 2-26

2-13 Operation in TropicalClimates . . . . . . . . . . . . . . . . . . . . . . . . . 2-27

2-14 Operation During Jamming ... 2-272-15 Secure Voice Operation . . . . . . . . 2-28

APPENDIX A. REFERENCES . . . . . . . . . . . . . . . . A-1APPENDIX B. COMPONENTS OF END

ITEM AND BASICISSUE ITEMSLISTS . . . . . . . . . . . . . . . . . . . . . B-1

APPENDIX C. ADDITIONAL AUTHORI-ZATION LIST . . . . . . . . . . . C-1

APPENDIX D. EXPENDABLE SUPPLIESAND MATERIALSLIST . . . . . . . . . . . . . . . . . . . . . . . D-1

iv

SECTION I.

1-1.

CHAPTER 1

I N T R O D U C T I O N

1-1

1-2. MAINTENANCE FORMS, RECORDS,AND REPORTS

a. Reports of Maintenance and UnsatisfactoryEquipment. Department of the Army forms and pro-cedures used for equipment maintenance will bethose prescribed by DA Pam 738-750, as containedin Maintenance Management Update.

b. Report of Packaging and Handling Deficiencies.Fill out and forward SF 364 (Report of Discrepancy(ROD)) as prescribed in AR 735-11-2/DLAR 4140.55/NAVMATINST 4355.73B/AFR 400-54/MCO 4430.3H.

c. Discrepancy in Shipment Report (DISREP) (SF361). Fill out and forward Discrepancy in ShipmentReport (DISREP) (SF 361) as prescribed in AR 55-38/NAVSUPINST 4610.33C/AFR 75-18/MCOP4610.19D/DLAR 4500.15.

1-3. REPORTING EQUIPMENT IMPROVEMENTRECOMMENDATIONS (EIR’s)

If your AN/PRC-126 Radio Set needs improvement,let us know. Send us an EIR. You, the user, are theonly one who can tell us what you don’t like aboutthe design. Put it on an SF 368 (Quality DeficiencyReport). Mail it to Commander, US Army Com-munications-Electronics Command and Fort Mon-mouth, ATTN: AMSEL-PA-MA-D, Fort Monmouth,New Jersey 07703-5000.

1-2

1-4. WARRANTY INFORMATION

The AN/PRC-126 Radio Set is warranted byMagnavox Government and Industrial ElectronicsCompany for 24 months after shipment or 90 daysafter deployment, whichever comes first. Report alldefects in material or workmanship to your super-visor, who will take appropriate action through yourorganizational maintenance shop.

SECTION II.

EQUIPMENT DESCRIPTION

1-5. PURPOSE AND USE OFRADIO SET AN/PRC-126

Radio Set AN/PRC-126 is a hand-held receiver-transmitter that provides two-way radio telephonecommunications. W h e n u s e d w i t h t h eTSEC/KYV-2A Secure Voice Module (SVM), it alsohas the capability of providing secure speechoperation.

1-3

1-6. LOCATION AND DESCRIPTIONOF MAJOR COMPONENTS

1-4

1-5

1-7. EQUIPMENT DATA

General

Frequency . . . . . . . . . . . . 30.000 MHz - 87.975 MHzAvailable channels . . . . . . . . . . . . . . . . . . . . . . . . . . 2320Channel spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 kHzPreset channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Preset channel spacing . . . . . . . . . . . . programmableModulation . . . . . . . . . . frequency modulation (fm)Range

Short antenna . . . . . . . . . . . . . . . . . 1648 ft (500 m)Long antenna . . . . . . . . . . . . . . . . . . . 9890 ft (3000m)

Battery Operating Time(Standard)

BA-5588/U Lithium . . . . . . . . . . . . . . . . . 70 hours(Optional)

BA-1588/U Mercury . . . . . . . . . . . . . . . . 42 hoursBB-588/Ni-CAD . . . . . . . . . . . . . . . . . . . 14 hours

Power output . . . . . . . . . . . . . . . . . . . . . . . . . 1 watt

Physical

Weight (Including battery and short antenna,no handset) . . . . . . . . . . . . . . . 2.6 lbs. , (1.2 kg)

Size R/T unit including battery . . . . . . . . . . . . 9.97 in.(253.2 mm) x 3.78 in. (96.0 mm) x

1.52 in. (38.6 mm)

1-6

Environmental

Operating temperaturerange . . . . . . . . . . . . . . . . . . . . . . . . . . -40°F to + 131°F

(-40°C to + 55°C)Watertightness ... to a depth of approximately

3 feet (0.91 meters)

1-8. ASSEMBLY AND PREPARATION FOR USE

This radio set was carefully inspected bothmechanically and electrically before shipment. Itshould be physically free of mars or scratches.Upon receipt, inspect the radio set as follows:

a. During unpacking, inspect the radio set forphysical damage that may have occurred duringshipment. If the equipment has been damaged,report the damage on SF 364, Report of Discrepan-cies (ROD).

b. Check the radio and supplied accessoriesagainst the packing slip to ensure the shipment iscomplete.

c. Assemble radio set as required in accordancewith paragraph 2-7 through 2-10.

1-7/(1-8 blank)

CHAPTER 2

O P E R A T I N G I N S T R U C T I O N S

SECTION I.DESCRIPTION AND USE OF

OPERATOR’S CONTROLS AND INDICATORS

2-1. GENERAL

You should not attempt to operate Radio SetAN/PRC-126 until you fully understand the opera-tion and function of the controls and indicators. Thenormal operating procedures are given in SectionIII of this Chapter.

2-2. CONTROLS AND INDICATORS

The following keyed illustrations and text serve toprovide the operator with a basic understanding ofthe AN/PRC-126 Radio Set controls and indicators.

2-1

2-2

2-2. CONTROLS AND INDICATORS

Key1

Control orIndicator

ANT matchswitch

FunctionSelects proper antennamatching network for theoperating frequencyselected or bypassesantenna matching net-works to provide a direct50 output. Warningtone sounds in speaker ifmatch is incorrect. Cor-responding frequenciesfor each switch positionare as follows:

A = 30-36 MHzB = 36-46 MHzC = 46-54 MHzD = 54-64 MHzE = 64-88 MHz

50 = 50 output*

* The 50 output is used only when it is de-sired to connect a 50 antenna system. This

optional antenna must provide a DC path ofor less between the antenna ter-

minal and ground when transmitting or re-ceiving.

2-3

2-2. CONTROLS AND INDICATORS - CONT

Key

2

3

4

5

Control orIndicator

SPKR/MIC

SQ DSBLbutton

INCRbutton

SET button

Function

Functions as built-inspeaker (receive) andmicrophone (transmit)when external handset isnot connected.

Pushbutton used todisable radio set squelchcircuit (noise will beheard in speaker).

Pushbutton used duringprogram mode to setvalue of each digit indisplay.

Pushbutton used to in-itiate the program mode,step through digits indisplay and load new fre-quency information. Ac-tive upon radio turn-on

2-4

2-2. CONTROLS AND INDICATORS - CONT

Key

5

6

Control orIndicator

SET button -(continued)

FREQdisplay

Function

for 10 secs. After 10sec period, this switch isused to momentarily lightthe display.

Five-digit Liquid CrystalDisplay (LCD) used to in-dicate the selectedpreset channel frequen-cy. In program mode“LOAD” indicates datapreviously displayed isnow loaded in theselected preset channelmemory location.

2-5

2-6

2-2. CONTROLS AND INDICATORS - CONT

Control orKey Indicator

7 AUDIO con-nector

8 OFF/VOL

control

9 A N TConnector

10 CHANselectorswitch

11 PUSH TOTALK (PTT)button

Function

Standard connector foruse with external hand-set H-250/U.

Turns radio set ON (CW)or OFF (full CCW). Ad-justs level of soundheard from radio set orhandset speaker.

Connects antenna or 50ohm cable to radio set.

Selects one of 10 presetoperating channels. Inprogramming mode,selects channel to beloaded.

Enables radio set totransmit when pressed.

2-7

SECTION II.

PREVENTIVE MAINTENANCECHECKS AND SERVICES

2-3. GENERAL

To ensure the AN/PRC-126 Radio Set is alwaysready for operation, it must be inspected as requiredso that defects may be discovered and correctedbefore they cause serious damage or failure.

a. Before you operate. Always keep in mind theCAUTIONS and WARNINGS. Perform the before (B)PMCS.

b. While you operate. Always keep in mind theCAUTIONS and WARNINGS. Perform the during(D) PMCS.

2-4. PMCS PROCEDURES

The Preventive Maintenance checks and servicesare required to keep your radio set in operating con-dition. If the radio set does not perform as required,report malfunctions or failures on DA Form 2404or refer to DA Pam 738-750. An explanation of col-umns found in the PMCS chart is as follows:

2-8

Interval Column - This column tells you whento do a certain check or service

Item to be Inspected Column - This column tellsyou what item to check or service

Procedure Column - This column tells you howto perform a service or check

Equipment Not Ready/Available if Column -This column tells you when and why the equip-ment cannot be used.

2-9

2-

10

2-11

SECTION III.

OPERATION UNDER USUAL CONDITIONS

2-5. NORMAL OPERATION.

NOTE

If required, refer to paragraph 2-7 toinstall battery.

a. Rotate OFF/VOL control CW to turn the radioset on. After a few seconds, the display shows thepreset frequency for the selected channel.

b. If new channel number is desired, set CHANswitch to desired channel number. Display willshow the preset frequency for the selectedchannel.

c. After channel selection is made, a warningtone is heard if ANT match switch is not in correctposition. Adjust ANT match switch to positionwhich disables warning tone.

NOTE

If required, refer to paragraph 2-6 toload new preset frequencies.

d. If battery voltage is low, four 400 Hz tones at 6second intervals will be heard. Replace battery inaccordance with paragraph 2-7.

2 - 1 2

e. Press and hold the SQ DSBL pushbutton.Adjust the OFF/VOL control for desired listeninglevel. Release SQ DSBL pushbutton to disablespeaker noise.

f. The radio set is now ready to operate.

g. Press PUSH TO TALK (PTT) button totransmit, release to receive.

h. Rotate OFF/VOL control fully CCW to turn theradio set OFF.

2-6. CHANNEL REPROGRAMMING

a. Set CHAN switch to the channel number tobe reprogrammed.

b. Turn radio off and then on and press SETbutton within 10 seconds.

c. Radio set is now in program mode. The displayindicates the left-most digit of the old frequency.(The display is also lighted)

d. Press INCR button until the display indicatesthe desired digit of the new frequency.

e. Press SET button. The next digit to the rightis displayed.

2-13

f. Repeat steps d and e until all digits are setfor the new frequency.

NOTE

The fourth and fifth digit of the fre-quency display increment is in 25 kHzsteps.

g. Press SET button. “LOAD” is displayed.Channel is now loaded with the new frequency.

h. Repeat steps a through g to reprogramother channels.

NOTE

If less than 10 secs lapse betweenloading of one channel and beginningthe programming of the next channel,the radio set does not need to be turn-ed off and back on to activate the pro-gramming mode. If at any time, morethan 10 secs lapse after a channel isprogrammed, turn radio off and thenback on to reactivate programmingmode.

2-14

2 - 1 5

2-7. BATTERY INSTALLATION/REMOVAL

To install a battery in the radio set, perform thefollowing steps:

A lithium-sulfur dioxide (Li-SO2) bat-tery used with the AN/PRC - 126 RadioSet contains pressurized sulfur diox-ide (SO2) gas. The gas is toxic, andthe battery MUST NOT be abused inany way which may cause the batteryto rupture. See the WARNING page ofthis manual.

DO NOT heat, short circuit, crush,puncture, mutilate, or disassemblebatteries.

DO NOT USE any battery whichshows signs of damage, such as bulg-ing, swelling, disfigurement, brown li-quid in the plastic wrap, a swollenplastic wrap, etc.

DO NOT test Li-SO2 batteries forcapacity.

DO NOT recharge Li-SO2 batteries.

2-16

If the battery compartment becomeshot to the touch, if you hear a hissingsound (i.e., battery venting), or smellirritating sulfur dioxide gas, IM-MEDIATELY Turn Off the equipment.Remove the equipment to a well ven-tilated area or leave the area.

DO NOT use a Halon type fire ex-tinguisher on a lithium battery fire.

In the event of a fire, near a lithiumbattery(ies), rapid cooling of the bat-tery(ies) is important. Use a carbondioxide (CO2) extinguisher. Control ofthe equipment fire, and cooling, mayprevent the battery from venting andpotentially exposing lithium metal. Inthe event that lithium metal becomesinvolved in fire, the use of a graphitebased Class D fire extinguisher isrecommended, such as Lith-X orMET-L-X.

DO NOT use water to extinguish Li-SO2 battery fires if a Shock hazard ex-ists due to high voltage electricalequipment in the immediate vicinity(i.e., greater than 30 volts, alternatingcurrent (ac) or direct current (dc)).

2-17

DO NOT store lithium batteries withother hazardous materials and keepthem away from open flame or heat.

DO NOT store batteries in unusedequipment for more than 30 days.Contact your local Fire Department forselection and approval of lithium bat-tery storage areas, and selection ofappropriate fire extinguishing equip-ment. Store lithium batteries in a cool(i.e., less than 130 degrees F), dry,well ventilated area. For bulk storageuse a sprinkler protected area, and asa second choice store in a non-combustible area.

DO NOT dispose of lithium batterieswith ordinary trash/refuse. Turn in bat-teries to your local serving DefenseReutilization and Marketing Office.

Only use batteries (items 1, 2 or 3,App. D) which have been authorizedfor this equipment.

2-18

a. Unfasten latches on battery housing; removebattery housing and old battery (if installed). (Han-dle case carefully as damaged case will not sealproperly. )

Ensure the Secure Voice Module (SVM)shorting plug (located next to the bat-tery terminal connector in the RT unitas shown in illustration on page 2-21),is installed and in good condition. Theradio set will not work unless the short-ing plug or an SVM is installed.

b. Apply thin coat of silicon compound (item 4App. D) to rubber seal on bottom of RT unit.

c. Plug battery (items 1, 2 or 3, App. D) intomating connector on

d. Replace batterytwo latches.

RT unit.

housing and secure with the

2-19

2-20

2-8. SECURE VOICE MODULE (SVM) INSTALLA-TION AND REMOVAL

INSTALLATION INSTRUCTIONS

a. Set PWR switch to OFF. Unfasten latches onbattery housing; remove housing and disconnectbattery.

b. Unplug SVM shorting plug and store in storagecavity. (Refer to illustration on page 2-20 forlocation.)

c. Apply a thin coat of silicone compound (item4, App. D) to rubber seal on bottom of RT unit; in-stall SVM and secure to RT unit by tightening thetwo captive securing screws. (Refer to illustrationon page 2-25 for locations.)

d. Apply a thin coat of silicone compound (item4, App. D) to rubber seal on bottom of SVM; in-stall battery and battery housing, and secure withlatches.

REMOVAL INSTRUCTIONS

a. Set PWR Switch to OFF. Unfasten latches onbattery housing; remove case and disconnectbattery.

2-21

Hold onto both RT unit and SVM whenloosening securing screws.

b. Loosen the two captive, securing screws onbottom of SVM and disconnect SVM from RT Unit.

Ensure the Secure Voice Module(SVM) shorting plug (located next tothe battery terminal connector on theRT unit as shown in illustration onpage 2-20), is installed and in goodcondition. The radio set will not workunless the shorting plug or an SVM isinstalled.

c. Remove SVM shorting plug from storagecavity and insert into connector as shown on page2-20.

d. Apply a thin coat of silicone compound(item 4, App. D) to rubber seal on bottom of RTUnit; install battery and battery housing, and securewith latches.

2-22

2-9. HANDSET lNSTALLATION/REMOVAL

INSTALLATION

a. Remove radio audio connector dust cover.

b. Mate handset connector and audio connec-tor with keyways aligned.

c. Press and rotate handset connector collarclockwise until connectors are securely mated(hand tight).

REMOVAL

a. Press and rotate handset connector collarcounterclockwise.

b. Separate connectors.

c. Install dust cover on radio audio connector.

2-23

2-10. ANTENNA (LONG OR SHORT)lNSTALLATION/REMOVAL

INSTALLATION

a. Mate antenna (including flexible antenna basefor long antenna only) to ANT connector on radio.

b. Rotate clockwise until secure (hand tight).

REMOVAL

a. Grasp antenna where connectors mate.

b. Rotate counterclockwise until connectorsseparate.

2-24

2-25

SECTION IV.

OPERATION UNDERUNUSUAL CONDITIONS

2-11. OPERATION AT LOW TEMPERATURES

Radio Set AN/PRC-126 can operate to -40 degreesFahrenheit (-40 degrees Celsius) below zero.However, you must keep the operating controls andconnectors free of ice. The same holds true for theantenna as ice on the antenna will reduce or distortthe signal. The battery should be kept as warm aspossible.

2-12. OPERATION AT HIGH TEMPERATURES

Radio Set AN/PRC-126 can operate to 131 degreesFahrenheit (55 degrees Celsius) above zero.However, in hot, dry climates, the connectors andoperating controls are subject to damage from dustand dirt. When not in use, keep the connectorscovered. Keep the operating controls as dust anddirt free as possible. Constant exposure to the suncould cause damage so try to keep the equipment out of the sun as much as possible.

2-26

2-13. OPERATION IN TROPICAL CLIMATES

In warm, damp climates, the equipment is subjectto damage from moisture and fungi. Wipe allmoisture and fungi from the equipment with a dry,lint-free cloth. Should Radio Set AN/PRC-126 hap-pen to fall into water, remember that it is water-tight to a depth of about 3 feet.

2-14. OPERATION DURING JAMMING

A common jamming procedure is the transmissionof a strong or annoying signal on your operatingchannel, making it difficult or impossible for you tomaintain communications. Sometimes this signalmay be from a friendly station. It is also possiblethat the unusual noise or interference may be dueto a bad Radio Set AN/PRC-126. To check it out,do the following:

a. Disconnect the antenna in accordance withparagraph 2-10.

b. Set ANT match switch to 50 position.

Do not key transmitter with antennaconnector shorted out.

c. Short out the antenna connector with avail-able material (e. g., wire or Long Antenna).

2-27

d. If you still have noise or interference, youhave a bad Radio Set AN/PRC-126. If the noise orinterference goes away, you are being jammed.Report jamming as soon as possible to officer incharge. One or more of the following antijammingprocedures may allow you to continue operatingRadio Set AN/PRC-126.

(1) Try to use a nearby obstruction as a screen.Position yourself so that the obstruction acts as ascreen between the radio and the possible sourceof interference.

(2) Point your radio in the direction of the dis-tant station you are communicating with. Tryseveral positions.

(3) Change the setting of the VOL control.This may raise the level of the desired signal enoughto be heard over the jamming signal.

(4) If none of the above works, get permissionto change to another channel.

2-15. SECURE VOICE OPERATION

If secure voice operation is required install securevoice module (refer to para 2-8). After secure voicemodule installation, the radio set is operated in ac-cordance with paragraph 2-5, Normal Operation.

2-28

APPENDIX A

REFERENCES

A-1. SCOPE

This appendix lists the forms and publications thatare referenced in this manual or that contain infor-mation applicable to the operation and maintenanceof Radio Set AN/PRC-126.

A-2. FORMS

DA Form 2028-2

DA Form 2404

Standard Form 368

Recommended Changes toEquipment TechnicalManuals

Equipment Inspection andMaintenance Worksheet

Quality Deficiency Report

A-3. TECHNICAL MANUALS

DA Pam 738-750 The Army MaintenanceManagement System(TAMMS)

A-1

A-3. TECHNICAL MANUALS - CONT

DA Pam 25-30 Consolidated Index ofArmy Publications andBlank Forms

SB11-573 Painting and PreservationSupplies Available for FieldUse for Electronics Com-mand Equipment

TM 750-244-2 Procedure for Destructionof Electronics Material toPrevent Enemy Use (Elec-tronics Command)

A-2

APPENDIX B

COMPONENTS OF END ITEM ANDBASIC ISSUE ITEMS LISTS

Section 1. INTRODUCTION

B-1. SCOPE

This appendix lists components of end item andbasic issue items for Radio Set AN/PRC-126 to helpyou inventory items required for safe and efficientoperation.

B-2. GENERAL

The Components of End Item and Basic Issue ItemsLists are divided into the following sections:

a. Section Il. Components of End Item. Thislisting is for informational purposes only, and is notauthority to requisition replacements. These itemsare part of the end item, but are removed andseparately packaged for transportation or shipment.As part of the end item, these items must be withthe end item whenever it is issued or transferredbetween property accounts. Illustrations are fur-nished to assist you in identifying the items.

b. Section Ill. Basic Issue Items. These are theminimum essential items required to place RadioSet AN/PRC-126 in operation,perform emergency repairs.

to operate it, and to

B-1

B-3. EXPLANATION OF COLUMNS

The following provides an explanation of columnsfound in the tabular listings:

a. Column (1) - Il lustration Number (Il lusNo). This column indicates the reference numberof the item as shown on the illustration.

b. Column (2) - National Stock Number. In-dicates the National stock number assigned to theitem and will be used for requisitioning purposes.

c. Column (3) - Description, Indicates the Na-tional item name and, if required, a minimumdescription to identify and locate the item. The lastline for each item indicates the FSCM (in paren-theses) followed by the part number.

d. Column (4) - Unit of Measure. In-dicates the measure used in performing the actualoperational/maintenance function. This measure isexpressed by a two-character alphabetical ab-breviation (e.g., ea, in, pr).

e. Column (5) - Quantity required (Qty rqr). In-dicates the quantity of the item authorized to beused with/on the equipment.

B-2

B-3

Section II.

Section II.

B-4

Section II.

Section II.

B-5

B-6

Section III.

Section III.

B-7/(B

-8 blank)

APPENDIX C

ADDITIONAL AUTHORIZATION LIST

Section 1. INTRODUCTION

C-1. SCOPE

This appendix lists additional items you areauthor ized for the support of Radio SetAN/PRC-126.

C-2. GENERAL

This list identifies items that do not have to accom-pany Radio Set AN/PRC-126 and that do not haveto be turned in with it. These items are all authoriz-ed to you by CTA, MTOE, TDA, or JTA.

C-3. EXPLANATION OF LISTING

National stock numbers, descriptions, and quan-tities are provided to help you identify and requestthe additional items you need to support thisequipment.

C-1

Section II.

Section II.

C-2

APPENDIX D

EXPENDABLE SUPPLIES ANDMATERIALS LIST

Section I. INTRODUCTION

D-1. SCOPE

This appendix lists expendable supplies andmaterials you will need to operate and maintain theRadio Set AN/PRC-126. These items are authoriz-ed to you by CTA 50-970, Expendable Items (Ex-cept Medical, Class V, Repair Parts, and HeraldicItems).

D-2. EXPLANATION OF COLUMNS

a. Column(1) - Item number. This number isassigned to the entry in the listing and is referenc-ed in the narrative instructions to identify thematerial (e.g., “Use cleaning compound, item 5,App. D”).

b. Column(2) - Level. This column identifies thelowest level of maintenance that requires the listeditem.

D-1

C - Operator/CrewO - Organizational MaintenanceF - Direct Support MaintenanceH - General Support Maintenance

c. Column(3) - National Stock Number. This isthe National stock number assigned to the item; useit to request or requisition the item.

d. Column(4) - Description. Indicates the Federalitem name and, if required, a description to iden-tify the item. The last line for each item indicatesthe Federal Supply Code for Manufacturer (FSCM)in parentheses followed by the part number.

e. Column(5) - Unit of Measure (U/M). Indicatesmeasure used in performing the actual maintenancefunction. This measure is expressed by a two-character alphabetical abbreviation (e.g., ea, in, pr).If the unit of measure differs from the unit of issue,requisition the lowest unit of issue that will satisfyyour requirements.

D-2

Section II.

Section II.

D-3/(D

-4 blan

k)

By Order of the Secretary of the Army:

Official:

R.L. DILWORTHBrigadier General, United States Army

The Adjutant General

CARL E. VUONOGeneral, United States Army

Chief of Staff

DISTRIBUTION:To be distributed in accordance with DA Form 12-51 literature

requirements for AN/PRC-68.