TM 11-6665-251-20

ORGANIZATIONAL MAINTENANCE MANUAL

RADIAC SETAN/VDR-2

(NSN 6665-01-222-1425)

TABLE OF CONTENTSPAGE i

SERVICE UPONRECEIPT

PAGE 2-1

TROUBLESHOOTINGPAGE 2-12

MAINTENANCEPROCEDURES

PAGE 2-14

PREPARATION FORSTORAGE OR SHIPMENT

PAGE 2-17

HEADQUARTERS, DEPARTMENT OF THE ARMY1 APRIL 1988

"This publication is required for official use or for administrative or operationalpurposes only. distribution is limited to U.S. Government Agencies. Otherrequests for this document must be referred to Commander, U.S. ArmyCommunications-Electronics Command, ATTN: AMSEL-ME-P, Fort Monmouth,NJ 07703-5000."

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

Change

No. 1

TM 11-6665-251-20C1

HEADQUARTERS,DEPARTMENT OF THE ARMY

Washington, DC, 15 September 1991

Organizational Maintenance ManualRadiac SetAN/VDR-2

(NSN 6665-01-222-1425) (EIC: KYF)

TM 11-6665-251-20, 1 April 1988, is changed as follows:

1. Remove old pages and insert new pages as indicated below. New or changed material is indicated by a verti-cal bar in the margin of the page. Added or revised illustrations are indicated by a miniature pointing hand.

Remove pages lnsert pages

i and ii i and ii1-1 through 1-6 1-1 through 1-62–5 and 2-6 2-5 and 2-6A-1 (A-2 Blank) A-1 (A-2 Blank)B-3 through B-6 B-3 through B-6

2. File this change sheet in the front of the publication for reference purposes.

Distribution authorized to the Department of Defense and DODcontractors only for official use or for administrative or operationalpurposes. This determination was made on 15 June 1991. Oth-er requests for this document will be referred to Commander,U.S. Army Communications-Electronics Command and FortMonmouth, New Jersey 07703-5007.

DESTRUCTION NOTICE - Destroy by any method that will pre-vent disclosure of contents or reconstruction of the document.

By Order of the Secretary of the Army:

CARL E. VUONOGeneral, United States Army

Chief of Staff

Official:

PATRICIA P. HICKERSONColonel, United States Army

The Adjutant General

DISTRIBUTION:

To be distributed in accordance with DA Form 12-51-E, block 1753, UnitMaintenance Requirements for TM 11-6665-251-20.

.TM 11-6665-251-20

Technical Manual

No. 11-6665-251-20

Organizational Maintenance Manual

Radiac Set

AN/VDR-2(NSN 6665-01-222-1425)

HeadquartersDepartment of the Army

Washington, DC, 1 April 1988

REPORTING ERRORS AND RECOMMENDING IMPROVEMENTS

You can help improve this manual. If you find any mistakes or if you know of away to improve the procedures, please let us know. Mail your letter, DA Form 2028(Recommended Changes to Publications and Blank Forms), or DA Form 2028-2located in the back of this manual direct to: Commander, US Army Communications-Electronics Command and Fort Monmouth, ATTN: AMSEL-LC-ME-PS, FortMonmouth, NJ 07003-5000. A reply will be furnished to you.

TABLE OF CONTENTS

Page

CHAPTER 1. INTRODUCTION

Section 1. GENERAL INFORMATION

1-1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11-2. Maintenance Forms, Records, and Reports . . . . . . . . . . . . . . . . . . . . . . 1-11-3. Reporting Equipment Improvement Recommendations (EIR) . . . . . . . . 1-11-4. Destruction of Army Electronics Materiel . . . . . . . . . . . . . . . . . . . . . . . . 1-11-5. Administrative Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21-6. Consolidated Index of Army Publications and Bank Forms . . . . . . . . . 1-21-7. Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Section Il. EQUIPMENT DESCRIPTION AND DATA

1-8. Equipment Characteristics, Capabilities, and Features . . . . . . . . . . . . . 1-21-9. Location and Description of Major Components . . . . . . . . . . . . . . . . . . 1-31-10. Equipment Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-41-11. Equipment Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

Section Ill. PRINCIPLES OF OPERATION

1-12. Equipment Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

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TM 11-6665-251-20

TABLE OF CONTENTS (CONTINUED)

Page

CHAPTER 2. ORGANIZATIONAL MAINTENANCE INSTRUCTIONS

Section I. REPAIR PARTS, SPECIAL TOOLS AND SUPPORT EQUIPMENT

2-1. Common Tools and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12-2. Special Tools and Support Equipment. . . . . . . . . . . . . . . . . . . . . . . . . 2-12-3. Repair Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Section ll. SERVICE UPON RECEIPT

2-4.2-5.2-6.2-7.2-8.2-9.2-10.

Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1Checking Unpacked Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1Installation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2Setting Attenuation Factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3Installing Radiac Set in Mount. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7Installing Vehicular Installation Kits . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10Removal of Radiac Set From Vehicle Mount . . . . . . . . . . . . . . . . . . . 2-11

Section Ill. PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS)

2-11. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Section lV. TROUBLESHOOTING

2-12. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-122-13. Troubleshooting Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-122-14. Troubleshooting Procedure: Display is Blank and Dark, Radiac Set

is Vehicle Mounted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13

Section V. MAINTENANCE PROCEDURES

2-15. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-142-16. Touch-up Painting instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-142-17. Replacement of Vehicle Power Converter . . . . . . . . . . . . . . . . . . . . . . 2-152-18. Replacement of Shock Mount . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16

Section VI. PREPARATION FOR STORAGE OR SHIPMENT

APPENDIX A.

APPENDIX B.

Section I.Section IIA.

llB.Section lllA.

IIIB.

Section lVA.IVB.

APPENDIX C.

Section I.Section Il.

ii

2-19. Packing for Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-172-20. Preparation for Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

MAINTENANCE ALLOCATION CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1MAINTENANCE ALLOCATION CHART RADIACSET, AN/VDR-2 . . . . . . . . B-3MAINTENANCE ALLOCATION CHART MOUNT, MT-6123/VDR-2 . . . . . . . B-4TOOL AND TEST EQUIPMENT REQUIREMENTS RADIAC SETAN/VDR-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-5TOOL AND TEST EQUIPMENT REQUIREMENTS MOUNT,MT-6123/VDR-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-5REMARKS RADIAC SET, AN/VDR-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-6REMARKS MOUNT, MT-6123/VDR-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-6

EXPENDABLE SUPPLIES AND MATERIALS LIST . . . . . . . . . . . . . . . . . . . C-1

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

EXPENDABLE SUPPLIES AND MATERIALS LIST . . . . . . . . . . . . . . . . . . . . C-1

TM 11-6665-251-20

CHAPTER 1INTRODUCTION

Section I. GENERAL INFORMATION

1-1. SCOPE.

Type of Manual: Organizational Maintenance Manual.

Model Number and Equipment Name: Radiac Set AN/VDR-2, herein referred to as radiac set.

Purpose of Equipment: Used to locate and measure radioactivity in the form of gamma rays and beta particles.Displays dose rates and total accumulated dose resulting from a fallout field.

1-2. MAINTENANCE FORMS, RECORDS, AND REPORTS.

The following paragraphs provide information on maintenance forms, records, and reports.

a. Reports of Maintenance and Unsatisfactory Equipment. Department of the Army forms and procedures usedfor equipment maintenance will be those prescribed by DA Pam 738-750, as contained in Maintenance ManagementUpdate.

b. Reporting of Item and Packaging Discrepanices. Fill out and forward SF 364 (Report of Discrepancy (ROD))as prescribed in AR 735-11-2/DLAR 4140.55/SECNAVlNST 4355.18/AFR 400-54/MCO 4430.3J.

c. Transportation Discrepancy Report (TDR) (SF 361). Fill out and forward Transportation Discrepancy Report(TDR) SF 361) as prescribed in AR 55-38/NAVSUPlNST 4610.33C/AFR 75-18/MCO P4610.19D/DLAR 4500.15.

1-3. REPORTING EQUIPMENT IMPROVEMENT RECOMMENDATIONS (EIR).

If your equipment needs improvement, let us know. Send us an EIR. You, the user, are the only one who can tellus what you don’t like about your equipment. Let us know why you don’t like the design or performance. Put iton an SF 368 (Product Quality Deficiency Report). Mail it to: Commander, US Army Communications-ElectronicsCommand and Fort Monmouth, ATTN: AMSEL-PA-MA-D, Fort Monmouth, New Jersey 07703-5000. We’ll send youa reply.

1-4. DESTRUCTION OF ARMY ELECTRONICS MATERIEL.

Destruction of Army electronics materiel to prevent enemy use shall be in accordance with TM 750-244-2.

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TM 11-6665-251-20

1-5. ADMINISTRATIVE STORAGE

Administrative storage of equipment issued to and used by Army activities will have preventive maintenance per-formed in accordance with the PMCS charts before storing. When removing the equipment from administrativestorage, the PMCS should be performed to ensure operational readiness. Disassembly and repacking of equip-ment for shipment or limited storage are covered in paragraphs 2-19 and 2-20 of

1-6. CONSOLIDATED INDEX OF ARMY PUBLICATIONS AND BANK FORMS.

Refer to the latest issue of DA Pam 25-30 to determine whether there are new editions, changes or additional publica-tions pertaining to the equipment.

1-7. CALIBRATION.

TM 11-6665-251-20.

Calibration requirements for the radiac set are located in TB43-180 (Calibration Requirements for the Maintenanceof Army Materiel). Procedures for calibration check and emergency calibration are contained in Appendix B ofthis manual.

Section Il. EQUIPMENT DESCRIPTION AND DATA

1-8. EQUIPMENT CHARACTERISTICS, CAPABILITIES, AND FEATURES.

• Light weight.

• Easy to use.

• Battery operated.

• Self-testing during operation or on demand by operator.

• Autoranging.

Detects, measures, and displays level of gamma radiation dose rate from 0.01 µGy/hr. to 100 Gy/hr.

Detects, measures, and displays level of beta particle dose rate from 0.01 µGy/hr. to 5 cGy/hr.

Measures, stores, and displays accumulated dose from 0.01 µGy to 9.99 Gy.

Flashes display to indicate reduced-accuracy condition when measuring dose rates between 10 Gy/hr. andabove.

Liquid crystal display (LCD) shows three digits, decimal point, and unit of measure rate or accumulated dose;also indicates low batteries and faults.

Audible or visual alarms independently preset for dose rate and accumulated dose.

Can be vehicle mounted with vehicle power actuating alarms and intercoms; computes and displays doserates external to vehicle.

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TM 11-6665-251-20

1-9. LOCATION AND DESCRIPTION OF MAJOR COMPONENTS.

WARNING

The high range detector contains 1 nanocurie of Thorium 232. Controlleddisposal required in accordance with AR 385-11.

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TM 11-6665-251-20

NOTE

The radiacmeter and probe are serialized and must be kepttogether as a set.

1-10. EQUIPMENT DATA.

To 15,000 feet (4572 m) above sea levelAltitude operating range:

Humidity:

Temperature operating range:

Storage temperature range:

Weight:

Length:

Width:

Depth:

Main power, all weather:

Vehicle power (whenvehicle mounted):

Main power battery life:

95 percent

-51 to 120°F

-60 to 160°F

(-46 to + 49°C)

(-51 to -71°C)

4.6 pounds (2.08 kg)

9.125 inches (232 mm)

6.875 inches (175 mm)

3.125 inches (79 mm)

Three BA-3090 dry batteries in parallel (9 V dc)

24 V dc

100 hours (minimum)

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TM 11-6665-251-20

1-11. EQUIPMENT CONFIGURATION.

SYSTEM

AN/VDR-2Radiac Set

AN/VDR-2Radiac Set

AN/VDR-2Radiac Set

Vehicle Type

COMPONENT

lM-243/VDR-2Radiacmeter

DT-616/VDR-2Probe

Pouch and Strap

lM-243/VDR-2Radiacmeter

DT-616/VDR-2Probe

Pouch and Strap

lM-243/VDR-2Radiacmeter

DT-616/VDR-2Probe

Pouch and Strap

M577A Carrier, Command Post . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

CONFIG-URATION

1

2

3

REMARKS

Carried by personnel for survey mode(refer to Operator’s Manual,TM 11-6665-251-10)

Carried by personnel for monitoringmode (refer to Operator’s Manual,TM 11-6665-251-10)

Installed in various vehicles (GroundRadiological Reconnaissance Mode,GRR). Pouch and strap are not used butare stored in vehicle. Vehicle lnstalla-tion Kits* and Mount** (neither suppliedwith radiac set) are listedbelow.

Installation Kit*

MK2001/VDR-2M113A1 Carrier, Armored Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

MK2574/VDR-2M151A1/A2 Truck, Utility .25 Ton (Jeep) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

MK2013/VDR-2M60A1 and M60A3 Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Installation Kit, Radiac Set

MK2012/VDR-2M2/M3 Vehicle, Bradley Fighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

MK2017/VDR-2M880 Truck, 1.25 Ton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

MK2039/VDR-2M1 Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

MK2016/VDR-2M998, HMMWV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac Set

MK2546/VDR-2

M1008, CUCV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation Kit, Radiac SetMK2545/VDR-2

M1A1 Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . lnstallation Kit, Radiac Set

MK2659/VDR-2

* Vehicle Installation Kits are required but not provided with the radiac set.

** Each installation Kit requires a vehicular mount (MOUNT MT-6123/VDR-2) which is not provided with the kitor the radiac set.

1-5CHANGE 1

TM 11-6665-251-20

Section Ill. PRINCIPLES OF OPERATION

1-12. EQUIPMENT FUNCTION.

1-6

TM 11-6665-251-20

CHAPTER 2ORGANIZATIONAL MAINTENANCE INSTRUCTIONS

Section l. REPAIR PARTS, SPECIAL TOOLS, AND SUPPORT EQUIPMENT

2-1. COMMON TOOLS AND EQUIPMENT.

Required tools are listed in Appendix B, Maintenance Allocation Chart, in this manual.

2-2. SPECIAL TOOLS AND SUPPORT EQUIPMENT.

None required.

2-3. REPAIR PARTS.

The Organizational Maintenance Repair Parts and Special Tools List (RPSTL), TM 11-6665-251-20P illustratesthe repair parts for Radiac Set AN/VDR-2.

Section Il. SERVICE UPON RECEIPT

2-4. UNPACKING.

a. For shipment overseas, the radiac set is packaged in a waterproof fiberboard carton. Corners and seamsare sealed with waterproof tape. Four such packages are usually overpacked in a waterproof fiberboard carton.

b. For domestic use, the radiac set is packedpacked in a fiberboard carton.

in a fiberboard carton. Four such packages are usually over-

CAUTION

Do not force or pry top or sides of fiberboard box. Damageto the radiac set may occur.

c. To remove units from the fiberboard box:

(1) First remove the staples from the metal strips around the fiberboard box.

(2) Next use shears or a pair of diagonal pliers to cut and fold back metal strips.

(3) Strip off the waterproof tape, open flaps, and remove units.

2-5. CHECKING UNPACKED EQUIPMENT.

a. Check the unit for possible shipping damage. If there is any shipping damage, report it on SF 364 (Report ofDiscrepancy (ROD).

b. Look at the packing slip and make sure all the components of the radiac set have been shipped. If not, reportthe problem, following the instructions in SF 361, Discrepancy in Shipment Report (DISREP).

c. The radiac set should not be used if a part is missing, even if the part does not affect proper operation of the unit.

d. Check to see if the equipment has been modified. If the equipment has been modified, the MWO numberwill be on the top panel, by the nomenclature plate.

e. Check to see if current MWOs have been applied. These would be listed in DA PAM 25-30.

2-1

TM 11-6665-251-20

2-6. INSTALLATION INSTRUCTIONS.

Configurations: 1. SURVEY MODE2. MONITORING MODE3. GRR (Vehicle Operation Mode)

a. Set PWR switch to OFF. Refer to paragraph 2-4aof the Operator’s Manual, TM 11-6665-251-10, and in-stall batteries.

b. Attach PROBE to RADIACMETER CABLE.

c. Refer to paragraph 2-4d of the Operator’s Manual,TM 11-6665-251-10, and perform pre-operational tests.

d. For use in configurations 1 and 2 (Survey Modeand Monitoring Mode) refer to paragraph 2-4 and 2-5of the Operator’s Manual, TM 11-6665-251-10. ConnectSTRAP to POUCH and insert RADIACMETER andPROBE into POUCH. For use in configuration 3(Vehicular Operation) refer to paragraphs 2-7 through2-10 of this manual.

2-2

TM 11-6665-251-20

NOTE

2-7.

The attenuation factor of the radiac set is factory set to 10.0,and must be adjusted before the radiac set is installed in avehicle. Each vehicle has a specific attenuation factor. (Referto the chart on page 2-5.) Adjustment of the attenuation factoris accomplished by adjustment of SLIDE SWITCH S2 locatedinside the radiacmeter.

a. Set PWR switch to OFF.

b. Loosen (do not remove) 8 CAPTIVE SCREWS.

c. Slide RADIACMETER HOUSING out ofRADIACMETER COVER just far enough to exposeSLIDE SWITCH S2.

d. SLIDE SWITCH S2 is designed with 10 rows of sliding contacts Iabelled A, B, C, D, E, F, G, H, J, and K.The sliding contact in each row can be positioned at any location 1 through 10 in that row. Rows G, H, and Jare used to set the attenuation factor.

2-3

TM 11-6665-251-20

NOTE

Do not change the setting of the sliding contacts not usedin setting the attenuation factor. This will cause the radiacset to function improperly.

e. Record the setting of all sliding contacts of SLIDE SWITCH S2 before setting the attenuation factor.

f. Refer to the following table and determine the attenuation factor for the vehicle in which the radiac set isbeing installed. SLIDE SWITCH S2 settings for the vehicles listed in the table are shown on the next page.

M1M2/M3M60A1/M60A3M113A1M151A1/A2M577AM880M1008M998

g. Press the tip of a ballpoint pen or other similarpointed instrument into the circular recess in the centerof the sliding contacts, and move the contacts to thesetting determined in step f., above.

h. To set an attenuation factor of 23.0, for example,set the sliding contact in row G to 2, row H to 3, androw J to 0.

20.09.1023.03.601.304.022.002.001.70

2-4

TM 11-6665-251-20

SLIDE SWITCH ATTENUATION FACTOR SETTINGS

NOTE

For vehicle M577A a factor of 4.0 has been set instead of4.02 because SLIDE SWITCH S2 cannot be set to settingssmaller than one-tenth.

2-5CHANGE 1

TM 11-6665-251-20

i.from

j.

k.

NOTE

If sliding contact settings are made with a resulting valuebelow 1.00, these settings will be ignored by the radiac setand an attenuation factor of 1.00 will be automaticallyassumed.

After setting the sliding contacts in rows G, H, and J, ensure that the other sliding contacts have not movedthe settings noted in step e above.

Set PWR switch to ON, display will indicate RATE.

Depress and hold ATTEN pushbutton, thendepress CLR/TEST pushbutton.

l. DISPLAY will indicate attenuation factor set instep g, above.

m. If the correct attenuation factor is displayed, setPWR switch to OFF, and proceed to step o, below.

n. If the wrong attenuation factor is displayed, an incorrect slide switch setting has been made. Repeat stepsa through m above. If the wrong attenuation factor is still displayed, refer the radiac set to the next higher levelof maintenance.

o. Slide RADIACMETER COVER over RADIAC-METER HOUSING.

p. Tighten 8 CAPTIVE SCREWS.

2-6

TM 11-6665-251-20

2-8.

NOTE

An installation kit is required to install the radiac set in avehicle. Refer to paragraph 1-10 to determine which installa-tion kit is to be used for each type of vehicle. The Mount,Radiac Set MT-6123/VDR-2 is not supplied with each installa-tion kit.

a. Set PWR switch to OFF.

CAUTION

Remove batteries prior to installing radiac set in mount.Radiac set can be damaged if batteries are left in.

b. Refer to paragraph 2-4a of the Operator’s Manual,TM 11-6665-251-10, and remove all three batteries.

c. Replace the batterypouch for future use.

cover and store batteries

d. Ensure that the probe is securely connectedradiacmeter cable.

2-7

TM 11-6665-251-20

e. Raise TOP COVER of mount and hinged PROBEPOSITIONING FLANGE.

f. Insert probe into mount between LEFT WALL andPROBE POSITIONING BRACKET.

g. Position probe to fit snugly against PROBE POSI-TIONING TAB, and locate HIGH RANGE DETECTORASSEMBLY as shown.

h. Position CONVERTER CABLE around probe asshown.

i. Connect CONVERTER CABLE PLUG to con-verter cable receptacle securely.

j. Lower PROBE POSITIONING FLANGE.

2-8

TM 11-6665-251-20

k. Position coil cord connecting the probe to theradiacmeter to the back of the unit through the open-ing between the top cover and shelf.

l. Position radiacmeter squarely on shelf aboveprobe and center between LOCKING LUGS.

m. Close top cover to position radiacmeter againstRADIACMETER POSITIONING TAB.

n. Tighten RETAINING SCREWS.

2-9

TM 11-6665-251-20

2-9.

NOTE

Installation kits are required to install the radiac set andmount in the vehicles. TM 11-6665-362-20&P contains com-plete installation instructions. Each installation kit also con-tains all parts, cables, connectors, and hardware requiredfor installation. A list of these installation kits appears inparagraph 1-10. The instructions provided with each installa-tion kit will also indicate how the vehicular power cable isto be attached to the radiac set and mount assembly asshown below.

a. Set ALM switch to AUD, set PWR switch to ON.

b. DISPLAY will indicate three zeros, then dose rate.

c. Refer to paragraph 2-4d of the Operator’s Manual,TM 11-6665-261-10, and perform pre-operational tests.

d. If vehicleheadset, check

is equipped withthat alarm can be

an intercom andheard distinctly.

2-10

TM 11-6665-251-20

2-10.

a. Set PWR switch to OFF.

b. Loosen (do not remove) two top cover RETAIN-ING SCREWS.

c. Raise TOP COVER and remove radiacmeter.

d. Disconnect CONVERTER CABLE from recep-tacle.

e. Remove probe and place radiacmeter and probein pouch with strap attached.

f. Lower TOP COVER and position CONVERTERCABLE within mount.

g. Tighten top cover RETAINING SCREWS.

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Section Ill. PREVENTIVE MAINTENANCE CHECKS AND SERVICES (PMCS)

2-11. GENERAL.

No preventive maintenance to the radiac set is required at the organizational level. Refer to the Operator’s Manual,TM 11-6665-251-10, for PMCS of the radiac set.

Section IV. TROUBLESHOOTING.

2-12. GENERAL

a. Troubleshooting at the organizational maintenance level requires that you locate faults as quickly as possible.

b. Repair or replace a defective unit or component only if authorized to do so. Repairs by organizationalmaintenance are limited by tools, test equipment, and replacement parts allocated to that level. Refer the problemto a higher level of maintenance if necessary.

c. Before using the Troubleshooting Table, paragraph 2-13, check your work order and talk to the equipmentoperator, if possible, to determine specific fault symptoms.

d. The Troubleshooting Table lists common problems that may occur during operation or maintenance of theradiac set. To use the Troubleshooting Table proceed as follows.

1. Locate the problem under the MALFUNCTION heading.

2. Perform the operations listed under the TEST or INSPECTION heading in the order designated.

3. Repair the unit as directed under the CORRECTIVE ACTION heading:

e. This Troubleshooting Table cannot list all problems that may occur, or provide all possible procedures tocorrect the problem. If you cannot locate the problem in the table, or if the problem is not corrected by followingthe procedures in the table, notify your supervisor.

2-13. TROUBLESHOOTING TABLE.

Table 2-1. Troubleshooting

MALFUNCTIONTEST OR INSPECTION

CORRECTIVE ACTION

a. DISPLAY IS BLANK AND DARK, RADIAC SET ON, NOT VEHICLE MOUNTED.Replace batteries. (Refer to paragraph 2-4a of Operator’s Manual, TM 11-6665-251-10.)

b. DISPLAY IS BLANK AND DARK, VEHICLE MOUNTED.Step 1. Check converter cable is connected to radiac set.

Connect converter cable as necessary.Step 2. Check radiac set in accordance with paragraph 2-14.

Repair as instructed in paragraph 2-17.

c. DISPLAY FLASHES “O” DURING OPERATION OR TESTING.Check probe connected to radiacmeter.

Connect probe as necessary.

d. DISPLAYED ATTENUATION FACTOR DIFFERENT FROM THAT ASSIGNED TO YOUR VEHICLE.Check slide switch S2 is set to correct attenuation factor. (Refer to paragraph 2-7.)Set attenuation factor in accordance with paragraph 2-7.

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2-14. TROUBLESHOOTING PROCEDURE: DISPLAY IS BLANK AND DARK, RADIAC SET IS VEHICLE

a.

b.

c.

d.

MOUNTED.

Refer to paragraph 2-10 and remove radiac set from mount.

Refer to paragraph 2-4a of the Operator’s Manual, TM 11-6665-251-10, and install fresh batteries.

If display remains blank and dark, refer radiac set to a higher level of maintenance.

If display lights up and indicates dose rate, radiac set is operating normally. Refer to paragraph 2-8 andinstall the radiac set in mount. Proceed to step e below.

e. Set PWR switch to OFF.

f. Disconnect VEHICULAR POWER CABLE fromVEHICULAR POWER CONVERTER.

g. Connect a digital voltmeter to vehicular powercable plug socket terminal A and terminal D.

h. If voltmeter indicates 10 to 40 V dc, the power con-verter is defective, refer to paragraph 2-17.

i. If voltmeter indicates other than in step h, above,the problem is in vehicle power supply. Refer the con-dition to your supervisor.

2-13

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Section V. MAINTENANCE PROCEDURES

2-15. GENERAL.

Organizational maintenance of the radiac set is limited to routine cleaning, removal of corrosion, touch-up painting,replacement of the power converter and replacement of shock mounts.

2-16. TOUCH-UP PAINTING INSTRUCTIONS.

NOTE

Do not brush on touch-up paint to areas not already painted.Do not paint display window or alarm light glass.

Lightly sand exterior of painted surfaces with fine sandpaper (Item b, Appendix C) to remove rust and corrosion.Protect base metal from further corrosion by brushing on two thin coats of paint. Refer to TB 43-0118 (FieldInstructions for Painting and Preserving Electronics Command Equipment).

2-14

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2-17. REPLACEMENT OF VEHICLE POWER CONVERTER.

a. Refer to paragraph 2-10 and remove radiac set from mount.

b. Remove cable clamp and retain along with hardware.

c. Remove 2 mounting screws and associated washers and retain.

d. Replace Vehicle Power Converter using existing hardware.

e. Replace cable clamp.

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2-18. REPLACEMENT OF SHOCK MOUNT.

a. Refer to paragraph 2-10 and remove radiac set from mount.

b. Remove top mounting screw and associated washers from shock mount and retain.

c. Remove 2 bottom nuts and associated washers and lift out 2 flat head screws (retain all hardware).

d. Replace shock mount and reinstall using existing hardware and shock mount spacer.

2-16

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Section VI. PREPARATION FOR STORAGE OR SHIPMENT

2-19. PACKING FOR SHIPMENT.

CAUTION

Batteries must be removed prior to shipment. Prolongedstorage of radiac set with batteries installed may damageequipment.

a. Refer to paragraph 2-4a of the Operator’s Manual, TM 11-6665-251-10, and remove batteries.

b. Refer to paragraph 2-4b of TM 11-6665-251-10 and install the radiacmeter and probe in the pouch and closepouch prior to shipment.

2-20. PREPARATION FOR STORAGE.

a. Refer to paragraph 2-4d of the Operator’s Manual, TM 11-6665-251-10, and perform pre-operational teststo ensure that radiac set is operational.

b. Refer to paragraph 2-4a of the Operator’s Manual, TM 11-6665-251-10, and remove batteries.

c. Refer to paragraph 2-4b of Manual TM 11-6665-251-10, and install radiacmeter in the pouch and close pouchprior to storage.

2-17/(2-18 Blank)

TM 11-6665-251-20

APPENDIX AREFERENCES

A-1. SCOPE

This appendix lists forms and publications that are referenced in this manual or that contain information applicableto the operation and organizational maintenance of the Radiac Set AN/VDR-2.

A-2. FORMS

DA Form 2028-2 Recommended Changes to Equipment Technical Manuals

Standard Form 361 Discrepancy in Shipment Report (DISREP)

Standard Form 364 Report of Discrepancy (ROD)

Standard Form 368 Quality Deficiency Report

A-3. PUBLICATIONS

DA Pam 25-30 Consolidated Index of Army Publications and Blank Forms

FM 3-12 Operational Aspects of Radiolocial Defense

TB 43-0118 Field Instructions for Painting and Preserving Communications-Electronics Equipment

DA Pam 738-750 The Army Maintenance Management System (TAMMS)

TM 750-224-2 Procedures for Destruction of Electronics Materiel to Prevent EnemyUse (Electronics Command)

TM 740-90-1 Administrative Storage of Equipment

TM 11-6665-251-10 Operator’s Manual: Radiac Set AN/VDR-2

TM 11-6665-362-20&P Organizational Maintenance Manual Including Repair Partsand Special Tools List: Radiac Set Installation Kits For Using Vehicles

A-1/(A-2 Blank)CHANGE 1

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APPENDIX BMAINTENANCE

Section I.

B-1. GENERAL

ALLOCATION CHARTINTRODUCTION

This appendix provides a summary of the maintenance operations for the Radiac Set. It authorizes categoriesof maintenance for specific maintenance functions on repairable items and components and the tools and equip-ment required to perform each function. This appendix may be used as an aid in planning maintenance operations.

B-2. MAINTENANCE FUNCTION

Maintenance functions will be limited to and defined as follows:

a. INSPECT. To determine the serviceability of an item by comparing its physical, mechanical, and/or elec-trical characteristics with established standards through examination.

b. TEST. To verify serviceability and to detect incipient failure by measuring the mechanical or electricalcharacteristics of an item and comparing those characteristics with prescribed standards.

c. CALIBRATE. To determine and cause corrections to be made or to be adjusted on instruments or testmeasuring and diagnostic equipments used in precision measurement. Consists of comparisons of two instruments,one of which is a certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy ofthe instrument being compared.

d. INSTALL. The act of emplacing, seating, or fixing into position an item, part, module (component or assembly)in a manner to allow the proper functioning of the equipment or system.

e. ADJUST. To maintain, within prescribed limits, by bringing into proper or exact position or by setting theoperating characteristics to the specified parameters.

f. REPAIR. The application of maintenance services (inspect, test, service, adjust, align, calibrate, replace)or other maintenance actions (welding, grinding, riveting, straightening, facing, remachining, or resurfacing) torestore serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, sub-assembly,module (component or assembly), end item, or system.

B-3. COLUMN ENTRIES

a. COLUMN 1, GROUP NUMBER. Column 1 lists group numbers, the purpose of which is to identify com-ponents, assemblies, sub-assemblies and modules with the next higher assembly.

b. COLUMN 2, COMPONENT/ASSEMBLY. Column 2 contains the noun names of components, assemblies,sub-assemblies, and modules for which maintenance is authorized.

c. COLUMN 3, MAINTENANCE FUNCTIONS. Column 3 lists the functions to be performed on the item listedin Column 2. When the items are listed without maintenance functions, it is solely for the purpose of having thegroup numbers in the MAC and RPSTL coincide.

d. COLUMN 4, MAINTENANCE CATEGORY. Column 4 specifies, by the listing of a “work time” figure inthe appropriate sub-columns, the lowest level of maintenance authorized to perform the function listed in Column3. This figure represents the active time required to perform that maintenance function at the indicated categoryof maintenance. If the number or complexity of the task within the listed maintenance function varies at differentmaintenance categories, appropriate “work time” figures will be shown for each category. The number of task-hours specified by the “work time” figure represents the average time required to restore an item (assembly,sub-assembly, component, module, end item, or system) to a serviceable condition under typical field conditions.

B-1

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This time includes preparation time, troubleshooting time, and quality assurance/quality control time in additionto the time required to perform the specific tasks identified for the maintenance functions authorized in themaintenance allocation chart. Sub-columns of Column 4 are as follows:

C - Operator/CrewO - OrganizationalF - Direct SupportH - General SupportD - Depot

e. COLUMN 5, TOOLS AND EQUIPMENT. Column 5 specifies by the code, those common tool sets (notindividual tools) and special tools, test, and support equipment to perform the designated function.

f. COLUMN 6, REMARKS. Column 6 contains an alphabetic code which leads to the remark in Section IV.Remarks, which is pertinent to the item opposite the particular code.

B-4. TOOL AND TEST EQUIPMENT REQUIREMENTS (SECTION Ill)

a. TOOLS OR TEST EQUIPMENT REFERENCE CODE. The numbers in this column coincide with the numbersused in the tools and equipment column of the MAC. The numbers indicate the applicable tool or test equipmentfor the maintenance functions.

b. MAINTENANCE CATEGORY. The codes in this column indicate the maintenance category allocated tothe tool or test equipment.

c. NOMENCLATURE. This column lists the noun name and nomenclature of the tools and test equipmentrequired to perform the maintenance functions.

d. NATIONAL/NATO STOCK NUMBER. This column lists the National/NATO stock number of the specifictool or test equipment.

e. TOOL NUMBER. This column lists the manufacturer’s part of the tool followed by the Federal Supply Codefor manufacturers (5 digit number) in parentheses.

B-5. REMARKS (SECTION IV)

a. REFERENCE CODE. This code refers to the appropriate item in Section II, Column 6.

b. REMARKS. This column provides the required explanatory information necessary to clarify items appear-ing in Section Il.

B-2

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Section IIA. MAINTENANCE ALLOCATION CHARTFOR

RADIAC SET, AN/VDR-2

B-3CHANGE 1

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Section IIB. MAINTENANCE ALLOCATION CHARTFOR

MOUNT, MT-6123/VDR-2

B-4

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Section IIIA. TOOL AND TEST EQUIPMENT REQUIREMENTSFOR

RADIAC SET AN/VDR-2

Section IIIB. TOOL AND TEST EQUIPMENT REQUIREMENTSFOR

MOUNT, MT-6123/VDR-2

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Section IVA. REMARKSRADIAC SET AN/VDR-2

REF.

CODE REMARKS

A Visual Inspection.

B Operational Test Using Bite.

C Calibration of Radiacmeter and Probe Using AN/UDM-2.

D Install Radiac Set in Vehicle.

E Set Attenuation Factor Switch.

F Service by Replacing Batteries (3 Each 9 Volts).

G Repair by Replacing Front Panel Assembly, Rear Panel Assembly, PCBs.

H Repair by Replacing Front Panel Assembly Gasket.

I Repair by Replacing Rear Panel Assembly Gasket, Power Supply Board, Battery HousingAssembly.

J Repair by Replacing High Range Detector Assembly, Low Range Assembly.

K Repair by Replacement of Mylar Window Assembly.

L Calibration Using AN/UDM-1A for Health/Safety Applications.

M Repair by Replacing Cable Assembly.

Section IVB. REMARKSMOUNT, MT-6123/VDR-2

REF.CODE REMARKS

A Visual Inspection.

B Repair by Replacing the Vehicular Power Converter, Shock Mounts.

C Test Output Using AN/PSM-45.

B-6CHANGE 1 PIN: 063662-001

TM 11-6665-251-20

APPENDIX CEXPENDABLE SUPPLIES AND MATERIALS LIST

Section I. INTRODUCTION

C-1. SCOPE

This appendix lists expendable supplies and materials you will need to operate and maintain the radiac set. Theseare authorized to you by CTA 50-970. Expendable Items (Except Medical, Class V, Repair Parts, and Heraldic Items).

C-2. EXPLANATION OF COLUMNS

a. COLUMN 1, ITEM NUMBER. This number is assigned to the entry in the listing and is referenced in thenarrative instructions to identify the material (e.g., “Use cleaning compound, Item 5, Appendix D”).

b. COLUMN 2, LEVEL. This column identifies the lowest level of maintenance that requires the listed item.

C — Operator/CrewO — Organizational MaintenanceF — Direct Support MaintenanceH — General Support MaintenanceD — Depot

c. COLUMN 3, NATIONAL STOCK NUMBER. This is the national stock number assigned to the item usedto request or requisition the item.

d. COLUMN 4, DESCRIPTION. Indicates the federal item name and, if required, a description to identify theitem. The last line for each item indicates the part number followed by the Federal Supply Code for Manufacturer(FSCM), in parentheses, if applicable.

e. COLUMN 5, UNIT OF MEASURE (U/M). Indicates the measure used in performing the actual maintenancefunction. This measure is expressed by a two-character alphabetical abbreviation (e.g., ea, in, pr). If the unit ofmeasure differs from the unit of issue: requisition the lowest unit of issue that will satisfy your requirements.

Section Il. EXPENDABLE SUPPLIES AND MATERIALS LIST

(1) (2) (3) (4) (5)UNIT

ITEM NATIONAL DESCRIPTION OFNO. LEVEL STOCK NO. PART NO. AND FSCM MEAS.

1 0 6135-01-063-1978 Battery, Dry Cold-Weather, BA-3090 ea

2 0 Cleaning Compound ea

3 0 8305-00-267-3015 Cleaning Cloth, Lint Free yd

4 0 7720-00-356-4694 1 Inch Bristled Brush ea

5 0 Paint pt

6 0 5350-00-598-5908 Sandpaper, No. 000 sh

C-1/(C-2 Blank)

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/VDR-2.

THE METRIC SYSTEM AND EQUIVALENTS

PIN: 063662-000