TM 11-6665-251-10

OPERATOR’S MANUAL

R A D I A C S E T

A N / V D R - 2

N S N 6 6 6 5 - 0 1 - 2 2 2 - 1 4 2 5

HEADQUARTERS, DEPARTMENT OF THE ARMY

1 MARCH 1988

D i s t r i b u t i o n a u t h o r i z e d t o t h e D e p a r t m e n t o f D e f e n s e a n d D O D c o n t r a c t o r s o n l y f o r

o f f i c i a l u s e o r f o r a d m i n i s t r a t i o n o r o p e r a t i o n a l p u r p o s e s . T h i s d e t e r m i n a t i o n w a s

m a d e o n 1 3 N o v e m b e r 1 9 8 7 . O t h e r r e q u e s t s f o r t h i s d o c u m e n t w i l l b e r e f e r r e d t o

C o m m a n d e r , U S A r m y C o m m u n i c a t i o n s - E l e c t r o n i c s C o m m a n d a n d F o r t M o n m o u t h ,

ATTN: AMSEL-ME-P, Fort Monmouth, NJ 07703-5000.

D E S T R U C T I O N N O T I C E — D e s t r o y b y a n y m e t h o d t h a t w i l l p r e v e n t d i s c l o s u r e o f

contents or reconst ruc t ion o f the document .

TM 11-6665-251-10

Technical Manual HEADQUARTERS

DEPARTMENT OF THE ARMY

No. 11-6665-251-10 Washington, DC, 1 March 1988

Operator’s Manual

Radiac SetA N / V D R - 2

(NSN 6665-01-222-1425)

REPORTING ERRORS ANDRECOMMENDING IMPROVEMENTS

You can help improve this manual. If you find any

mistake or i f you know of a way to improve theprocedures, please let us know. Mail your letter orDA Form 2028 (Recommended Changes to Publications

and Blank Farms) direct to: Commander, US ArmyCommunications-Electronics Command and FortMonmouth, ATTN: AMSEL-ME-MP, Fort Monmouth, New

Jersey 07703-5000. In either case, a reply will be sentto you.

i

TABLE OF CONTENTSP a r a - P a g e graph

CHAPTER 1. INTRODUCTION

Section I. GeneralScope . . . . . . . . . . . . . . . . . . . . . 1-1Maintenance Forms,

Records, and Reports . . . . 1-2Reporting Equipment

ImprovementRecommendations (EIR) . 1-3

Administrative Storage . . . . 1-4Destruction of Army

Electronics Materiel. . . . . 1-5Nomenclature

Cross-Reference List . . . 1-6List of Abbreviations and

Acronyms . . . . . . . . . . . . . . . 1-7Glossary . . . . . . . . . . . . . . . . . . . 1-8

Section Il. EQUIPMENT DESCRIPTIONAND DATA

1-1

1-2

1-21-2

1-3

1-3

1-31-4

Equipment Characteristics,Capabilities,and Features . . . . . . . . . . . . 1-9 1-5

Description ofComponents . . . . . . . . . . . . . 1-10 1-6

Equipment Data . . . . . . . . . . . 1-11 1-10

Section III. TECHNICAL PRINCIPLES OFOPERATION

Equipment Function . . . . . . . 1-12 1-14

ii

TABLE OF CONTENTS (CONTINUED)

Para- Pagegraph

CHAPTER 2. OPERATINGINSTRUCTIONS

Section I. DESCRIPTION ANDUSE OF CONTROLSAND INDICATORS

Equipment Controlsand Indicators . . . . . . . . . . . 2-1 2-1

Section II. PREVENTIVEMAINTENANCECHECKS ANDSERVICES (PMCS)

Preventive Maintenance. . . 2-2 2-4Routine Checks . . . . . . . . . . . . 2-3 2-4

Section III. OPERATION UNDERUSUAL CONDITIONS

Assembly and Preparationfor Use . . . . . . . . . . . . . . . . . . 2-4 2-6

Equipment Applications . . . 2-5 2-17Automatic Testing During

Operation . . . . . . . . . . . . . . . 2-6 2-22Normal Operating

Procedures . . . . . . . . . . . . . 2-7 2-25Operation in Unusual

Weather . . . . . . . . . . . . . . . . 2-8 2-42Operation Inside Shelters . 2-9 2-43Emergency Procedures . . . . 2-10 2-43

iii

TABLE OF CONTENTS (CONTINUED)

Para- Pagegraph

CHAPTER 3. OPERATORMAINTENANCEINSTRUCTIONSTroubleshooting

Procedures . . . . . . . . . . . 3-1 3-1Battery Replacement . . . . 3-2 3-2

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

END ITEM ANDBASIC ISSUE ITEMSLIST . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Section I. INTRODUCTION . . . . . . . . . . . . . . . . . . . . B-1

II. COMPONENTS OF ENDITEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3

III. BASIC ISSUE ITEMS . . . . . . . . . . . . . . B-5

APPENDIX C. EXPENDABLESUPPLIES ANDMATERIALS LIST . . . . . . . . . . . . . . . C-1

Section I. INTRODUCTION . . . . . . . . . . . . . . . . . . . . C-1

II. EXPENDABLESUPPLIES ANDMATERIALS LISTS . . . . . . . . . . . . . . . . C-2

iv

CHAPTER 1

INTRODUCTION

Section I. GENERAL INFORMATION

1-1. SCOPE

Type of ManuaI: Operator’s Manual

Model Number and Equipment Name:

AN/VDR-2 Radiac Set, hereinreferred to as radiac set.

Purpose of Equipment:

Used to locate andmeasure radioactivityin the form of gammarays and betaparticles, Displaysdose rates and total R A D I A C M E T E Raccumulated doseresulting from afallout field.

PROBE

1-1

1-2. MAINTENANCE FORMS, RECORDSAND REPORTS

a. Reports of Maintenance and UnsatisfactoryEquipment. Department of the Army forms andprocedures used for equipment maintenancewill be those prescribed by DA Pam 738-750, ascontained in Maintenance Management Update.

b. Report of Packaging and HandlingDeficiencies. Fill out and forward SF 364 (Reportof Discrepancy (ROD)) As prescribed in AR 735-11-2/DLAR 4140.55/NAVMATlNST4355.73B/AFR 400-54/MCO 4430.3H.

Discrepancv in Shipment Report (DISREP)(SF 361). Fill out and forward Discrepancy in Shipment Report (DISREP) (SF 361) as prescribedin AR 55-38/NAVSUPINST 4610.33C/AFR 75-18/MCO P4610.19D/DLAR 4500.15.

c.

1-3. REPORTING EQUIPMENT IMPROVEMENTRECOMMENDATIONS (EIR)If your equipment needs improvement, let us

know. Send us on EIR. You, the user, are the

only one who can tell us what you don’t likeabout the design. Put it on an SF 368 (QualityDeficiency Report). Mail it to Commander, USArmy Communications-Electronics Command

and Fort Monmouth, ATTN: AMSEL-ME-MP, FortMonmouth, New Jersey 07703-5000. We’ll send

you a reply.

1-4. ADMINISTRATIVE STORAGEAdministrative storage of equipment issued to

1 -2

and used by Army activities will have preventivemaintenance performed in accordance with thePMCS charts before storing. When removing theequipment from administrative storage the PMCSshould be performed to assure operationalreadiness.

1-5. DESTRUCTION OF ARMYELECTRONICS MATERIEL

Destruction of Army electronics materiel toprevent enemy use shall be in accordance withTM 750-244-2.

1-6. NOMENCLATURE CROSS-REFERENCE LIST

Common names are used when the major compo-nents of the radiac set are mentioned in thismanual.

Common Name Official NomenclatureRadiac Set Radiac Set

AN/VDR-2

Radiacmeter Radiacmeter lM-243/VDR-2

Probe Probe, Radiac DT-616/VDR-2

Pouch Pouch, Radiac Set

Strap Strap, Radiac Set

1-7. LIST OF ABBREVIATIONS ANDA C R O N Y M S

Acronyms are spelled out the first time they appearin this manual. A list of abbreviations and acronymsfollows:

1 -3

Gy radiation absorbed dose(gray)

µ G y microgray

cGy centigray

G y / h r grays per hour

µ G y / h r micrograys per hour

cGy /h r centigrays per hour

NBC nuclear/biological/chemical

1 - 8 . G L O S S A R Y

DoseRate

Dose

GammaRay

BetaParticles

X-rays

Autoranging

An amount of radiation given off orabsorbed within a given period of time.(µGy/hr, cGy/hr, Gy/hr).

An accumulative amount of radiationgiven off or absorbed. (µGy, cGY, GY).

Electromagnetic radiation of high energy(high penetration).

Negatively charged particles moving at highspeed (low penetration).

Electromagnetic radiation of high energyhaving wavelength shorter than those inthe ultraviolet region (low penetration).

The AN/VDR-2 display will automaticallyprovide the proper readings and units overits entire operating range without theneed for mechanical switching or otheroperator actions.

1 - 4

At tenuat ion A multiplying number assigned toFactor vehicles or shielded enclosures to

account for the at tenuat ion ofgamma radiation by the vehicleor the enclosure.

Sect ion I I EQUIPMENT DESCRIPTION ANDD A T A

1-9 . EQUIPMENT CHARACTERISTICS,CAPABILIT IES, AND FEATURES.

C H A R A C T E R I S T I C S

● Lightweight

● Easy to use

Bat tery opera ted

Self-testing during operation or on demandby operator

● Autoranging

CAPABILITIES

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

● Detects and displays level of beta particledose rate from 0.01 µGy/hr. to 5 cGy/hr.

● Measures, stores, and displays accumulateddose from 0.01 µGy to 9.99 Gy.

1 - 5

● Flashes display to indicate reduced-accuracycondition when measuring dose rates from10 Gy/hr. and above.

FEATURES

● Liquid crystal display (LCD) shows three digits,decimal point, and unit of measure for doserate or accumulated dose; also indicateslow batteries and faults

● Can be vehicle mounted with vehicle poweractuating alarms and intercoms; computesand displays dose rates external to vehicle

● Audible or visual alarm independently pre-set for dose rate and accumulated dose

1-10. DESCRIPTION OF COMPONENTS

The radiac set is made up of four separate piecesof equipment:

● Radiacmeter

● Probe

● Pouch

● Strap

NOTE

Radiacmeter and probe are serialized andmust be kept together as a set.

1 -6

The functions of the major components of thisequipment are:

RADIACMETER - Con-tains batteries, controls,indicators, andelectronics needed tomeasure and displaydose rate, dose, andother indications.

LOUDSPEAKER - Pro-vides audible alarm

DISPLAY - Showsdose/hr or accumulateddose, low batteries,alarm set points, andtest and fault indicators.

1 -7

BATTERY WELL COVEREncloses battery wellcontaining three dry cellbatteries providing powerto the radiac set.

CONVERTER CABLERECEPTACLE (SHOWNWITH CAP IN PLACE)Connects radiacmeter tovehicle power convertercable.

CAUTION

The radiac set will not operate with probedetached and can be damaged if probe isattached or detached with PWR switch inON position.

1-8

PROBE - Attaches to PROBE RECEPTACLEradiacmeter with coil cord and - Accepts plug fromconnector; contains twodetectors, high-voltage power

radiacmeter cable.

supply, and other circuits.

WARNING

The high rangedetector contains 1nanocurie of Thorium232, controlled disposalrequired in accordancewith AR 385-11.

HOUSING - Contains

low-range detector andelectronic circuitry.

DETECTOR GUARD -Protects low-range detector,

keeps moisture out of probe.

COVER - Protects detectoragainst damage; can be usedclosed to detect gammaradiation, must be opened todetect beta particles.

1-9

POUCH - Holds radiacmeterand probe during operation ortransport and stores spare setof batteries. May be attachedto web belt with belt loops.

1-11. EQUIPMENT DATA

ENVIRONMENTAL

Altitude operating To 15,000 feetrange: (4,572 m) above

sea level

Humidity: 95 percent

Temperature operatingrange: -51 to 120°F

(-46 to +49°C)

1-10

Storage temperaturerange: -60 to 160°F

(-51 to + 71°C)

Water resistance: Immersion proof to adepth of 3 feet(914.4 mm) ofwater for 2 hours

WEIGHTS AND DIMENSIONS

Radiac set in pouch:

Weight: 4.6 pounds (2.08 kg)Length: 9.125 inches (232 mm)Width: 6.875 inches (175 mm)Depth: 3.125 inches (79 mm)

POWER

Main power,all weather

Vehicle power(when vehiclemounted):

Main Powerbattery life:

Three BA-3090 drybatteries in parallel(9 V dc) (Item 1, Appx C)

24 V dc

100 hours (minimum)

1-11

OPERATIONAL

Detectors:

Range:

a) Low-range detec-tor (dose rate):

b) Low-range detec-tor (accumulateddose):

c) High-range detec-tor (dose rate):

d) High-range detec-tor (accumulateddose):

Two detectors (low-range for gamma andbeta radiation, high-range for gamma ra-diation), both located inprobe at approximatelythe same location.

0.01 µGy/hrto 5C Gy/hr.

0.01 µGy to9.99 Gy.

3 cGy/h to100 Gy/Hr.

0.01 µGy to9.99 Gy.

1 - 1 2

Dose:

Alarms:

Overall detecting range:

Dose rate: 0.01 µGy/hr. to100. Gy/hr forgamma rays and0.01 µGy/hr. to5 C Gy/hr for betaradiation

Accumulateddose: 0.01 µGy to

9.99 Gy.

Accuracy:

Dose rate: ±20 percent (overallsystem error) up to10.0 Gy/hr.

±25 percent (overallsystem error) up to100 Gy/hr.

±20 percent (overallsystem error) up to9.99 Gy.

Audio and visual inde-pendently adjustableto any level from0.0 µGy/hr. to 100Gy/hr. for dose rateand 0.01 µGy to9.99 Gy foraccumulated dose.

1 - 1 3

Section III. TECHNICAL PRINCIPLESOF OPERATION

1-12. EQUIPMENT FUNCTION

1 Gamma rays and beta particlesfrom radioactive source travel inall directions.

2 Two detectors in probe produceelectrical signals on contact withgamma rays and beta particles.

1-14

3 Radiacmeter converts signalsfrom probe into dose rates andaccumulated dose; activatesalarm when preset alarm levelsae exceeded.

4 Display shows dose rate andaccumulated dose values, alarmset levels, battery conditions,and test and fault indicators.

5 Control panel switches andindicators permit operator to setalarm levels for audible or visualdisplay, select display readings,and perform equipment tests.

1-15/(1-16 Blank)

CHAPTER 2OPERATING INSTRUCTIONS

Section I. DESCRIPTION AND USE OFCONTROLS AND INDICATORS

2-1. EQUIPMENT CONTROLS ANDINDICATORS

a. TOGGLE SWITCHES AND ALARM LIGHTS

RATE AND DOSE LIGHTS - Illuminatewhen dose rate or accumulated dose alarmset points are exceeded and alarm is set toVlS.

POWER - Turns unit ON or OFF.

THREE-POSITION ALARM

● OFF (center) - NO alarm occurs.● AUD (top) - Alarm sounds when either

alarm set point is exceeded.● VIS (bottom) - RATE or DOSE light

illuminates when either alarm set point isexceeded.

2-1

b. PUSHBUTTONS

CLEAR/TEST - Pressed to start operatingtest; used with other buttons to performvarious test functions.

DOSE PER HOUR - Used with otherbuttons to:

Set dose rate alarm. Display dose rate alarm set point Clear accumulated dose.

ACCUMULATED DOSE - Pressed todisplay accumulated dose; used with otherbuttons to perform various functions.

ATTENUATION - Press to display doseexternal to vehicle when vehicle mounted;used with CLR/TEST button to readattenuation factor.

2 -2

DOSE UNITS - Proper symbol (µGy, cGY, Gy)activated automatically according toradiation reading.

2-3

Section II. PREVENTIVE MAINTENANCECHECKS AND SERVICES (PMCS)

2-2. PREVENTIVE MAINTENANCE

Preventive maintenance consists of routine checksof the equipment before and after each mission, orat any time they are necessary. Routine checksinclude cleaning, dusting, and washing the set;checking for worn cables; replacing receptaclecovers; and putting away items that are not used.

Problems discovered during routine maintenanceshould be referred to organizational maintenance.

2-3. ROUTINE CHECKS

Routine checks to be made of the radiac set are:

● Check all connecting cables, receptacles, andplugs for cracks and breaks.

CAUTIONTurn unit off before discon-necting or reconnecting probe.

● Check that cable receptacle pins are unbrokenand straight. There should be three pins in thevehicle mount receptacle on the back of theradiacmeter and six in the receptacle locatedon the probe.

2-4

CONTROL AND DISPLAY PANEL

●

●

Check for loose or broken display lights orlight covers.

Inspect panel toggle switches andpushbuttons for ease of movement orevidence of mechanical damage.

OUTSIDE SURFACES AND POUCH

Remove dust, moisture, and loose dirtfrom outside surfaces of radiacmeter andprobe with clean soft cloth.

Remove grease, fungus, and ground-indirt from equipment pouch.

BATTERIES

●

●

Inspect battery well gasket (see para2-4a). Refer radiac set to higher level ofmaintenance only if gasket will no longerseal.

Inspect battery contacts; remove anycorrosion using pencil eraser.

2 - 5

Section III. OPERATION UNDERUSUAL CONDITIONS

2-4. ASSEMBLY AND PREPARATION FOR USE

a. BATTERY INSTALLATION/REPLACEMENT

(1) Make sure PWR switch is OFF (down).

(2) Loosen, but do not remove,captive screws.

2 - 6

CAUTION

When batteries are removedfrom the radiac set memoryis retained for only 5minutes.

(3) Remove battery well coverand three batteries.

2-7

b. INSTALLING RADIAC SET IN POUCH

(1) Orient pouch so that tap cover is openand away from you. Install probe in the leftcompartment by passing the straightsection of the tail card nearest the probe

connector through the opening in thecompartment flaps. (Note the orientation of

the high range assembly.) Push probe to thebottom of pouch.

2 - 8

(2) Store coil cord at the bottom of the righthand compartment. Install radiacmeterdirectly above coil cord as shown.

RADIACMETER

COIL CORD

2 - 9

c. PREOPERATIONAL TEST EXPLANATION

Before each mission, a series of pre-operational tests must be performed tomake sure that the radiac set is operating.The radiac set is self-testing and the pre-operational tests are performed auto-matically by the equipment. The operatoris required to reposition the alarm switchand observe closely that the proper displaysare shown for the test being conducted.

NOTE

A summary of these tests is listed insequence below. Although these tests seemdifficult at first, they are easy to performafter following the sequence a few times.

(1) Segment Test - Segments of the digitaldisplay, decimal points and unit readout aredisplayed for about 10 seconds todetermine that all display segments areworking. The alarm test (step (2) below),must be performed during the 10seconds the segments are displayed.

2 - 1 0

(2) Alarm Test - Operator switches ALM to allpositions to check that the alarm sounds andshuts off and that the lights work at the propertimes.

(3) Digit/Unit Test - After the segment test, the unitautomatically proceeds through the sequence ofnumbers, decimal places, and dose units to testthat they are working in the proper order. Thistest and the following electrical tests take about60 seconds.

(4) Electrical Tests - Immediately following thesequential displays, a series of eight internalelectrical tests occurs. During these tests, one-digit numbers may appear on the display. Theseare the code numbers related to the test beingmade and you can ignore them.

2-11

d.

(1)

(2)

(3)

(4)

NOTEAll of the following paragraphs must beread before starting test procedures.

PREOPERATIONAL TEST PROCEDURES

Set PWR to ON (up).

Set ALM switch to AUD (up).

Press and hold CLR/TEST button untilalarm sounds 2 seconds, then release.

When segment display appears, check thatyour display is exactly as shown here, andthen perform all of step (5) within 10 seconds.

2 - 1 2

(5) Set ALM switch to OFF (center). Alarmsound stops.

Set ALM switch to VIS (down). RATE andDOSE lights come on.

Set ALM switch back to AUD (up). Lightsgo out, alarm sounds.

Set ALM switch to OFF (center).

(6) At the end of the 10-second segment test,the digit/unit test begins with three zerosand the sequence shown. Check eachdisplay in the sequence for correctness ofall characters, including decimals.

2 - 1 3

(7)

(8)

(9)

During the electrical tests that startimmediately after the 999Gydisplay, youmay see one-digit codes on the display. Youcan ignore these codes.

If all tests are OK, after 10 to 60 seconds, aflashing 9 appears with the pulsating alarm.When you see the flashing 9, proceed tostep (10) below.

FLASHING

If there is a fault discovered during this test,a flashing 0 appears and the alarmpulsates. Turn unit OFF.

FLASHING

2-14

(10) Press and release CLR/TEST button.

Preoperational tests are complete. Display again

shows the three zeros (a) and then indicates doserate, which is variable (b). Radiac set is ready for

normal operation.

CLR/TESTBUTTON

2-15

(11) If any of the following events occur duringthe preoperational tests, turn unit OFF and

send to organizational maintenance for

repair.

Power does not come on (step 1).

Alarm does not sound (step 3). Decimal points, dose units, or any segment

of the display are not in position orotherwise not exactly as shown (step 4).

● Alarm does not turn off (step 5).

RATE and/or DOSE lights do not come on(step 5).

● Alarm does not turn on again (step 5).

● Digit/unit test are not displayed in entirety,in sequence exactly as shown (step 6).

● The electrical tests end with the displayshowing a flashing 0 (step 9).

NOTE

When performing preoperational tests in

an area where the background radiation isunusually low or when the probe isshielded, it is statistically possible for thehigh range tube not to produce a count inthe time allowed in the test. This will cause

a flashing zero to appear when in fact nofault exists. If the numeral 7 appears priorto a flashing zero, repeat the pre-

operational test. If a flashing 9 appears onthe retest no fault exists. If the flashing zerorepeats, refer the unit to maintenance.

2 - 1 6

2-5. EQUIPMENT APPLICATIONSThere are three methods used to locate radiological

contamination - Surveying, Monitoring, and

Ground Radiological Reconnaissance:

● Surveying - Surveys are conducted to findthe extent and intensity of contamination.There are two types, aerial and ground.

NOTE

To perform aerial surveys, auxiliaryequipment is required which is notsupplied with the AN/VDR-2.

● Aerial surveys cover a large area fasterthan other methods. They are more flexibleand require fewer personnel and lessexposure of personnel.

● Ground surveys use unit equipment andcan be performed in any type of weather orat night. They are more accurate than aerialsurveys.

Monitoring - Monitoring is performed todetermine the presence and intensity ofresidual radiation.

Area monitoring is performed periodically orcontinuously to provide early warning anduseful radiological data.

● Personnel, food, and equipment monitoringis performed to detect beta and low levels ofgamma radiation.

2 - 1 7

● Ground Radiological Reconnaissance (GRR)- GRR is the process of detecting radiationand measuring it before a unit moves intoor through an area. Normally, the AN/VDR-2 will be mounted and attached to vehiclepower.

NOTE

When monitoring for beta radiation, theaudible alarm set point should be used. Thisallows the operator to pay attention topositioning the probe rather than watchingthe visual display. Performance of allradiological measurements, regardless ofmode of operation, shall be in accordancewith FM 3-3 and FM 3-5.

a. SURVEY AND MONITORING MODES

In the survey or monitoring modes,the operator wears the radiac set in the pouch with the PWR switch in theON position. The probe can be carriedeither in the pouch or held in thehand, as desired.

2 - 1 8

The probe cover, located at the end ofthe probe, is closed when measuringgamma radiation. Detection isprovided by both low-range and high-range detectors located in the probe.The radiac set autoranges from low tohigh range (0.01 µGy/-hr to 100Gy/hr.) smoothly and withoutinterruption.

CAUTION

The window guard may be ruptured bysharp objects. Use extreme care to protectwindow guard when probe window is open(when monitoring for beta radiation).

When monitoring for beta radiation,the probe must be hand held, and theprobe window cover must be open toallow beta particles to enter thewindow of the low-range detector.Only the low-range detector is capableof detecting beta particles. The rangeof beta radiation is 0.01 µGy/hr to 5cGy/hr.

2 - 1 9

b. GROUND RADIOLOGICALRECONNAISSANCE (VEHICULAROPERATION)

CAUTION

The radiacmeter batteries must be removedwhen using vehicular power.

When used in a vehicle, the radiac set is placedin a mount and installed using an installation kit.The mount(MT-6123/VDR-2) is not supplied withthe AN/VDR-2 or the installation kit. Vehicularpower is used to operate the set through avoltage converter (24V to 7.8V).

2-20

NOTE

When the unit is mounted in a vehicle andthe vehicle is turned off, the power to theunit is lost. If this condition lasts for morethan 5 minutes, the unit memory is lost.When memory is lost, the prioraccumulated dose cannot be recalled, andthe alarm set points set previously by theoperator are also lost. Alarm set points willrevert to the points set internally in theradiacmeter, until the operator sets newalarm points from the front panel.

If the commander requires that prioraccumulated dose be maintained and thevehicle is turned off, batteries must beinstalled in the radiac set within 5 minutesfrom the time the vehicle is turned off. Seeparagraph 2-10c(1)for battery replacementprocedure.

2-21

2-6. AUTOMATIC TESTINGDURING OPERATION

In addition to the pre-operational tests describedin paragraph 2-4c, the radiac set tests itselfcontinuously during operation. These tests checkthe main battery condition, counting and timingsequences, internal circuitry, voltage, anddetectors.

a. LOW-BATTERY INDICATORIf a low battery condition is detected during thesetests, the /hr sign will be shown flashing on thedisplay. Approximately 10 hours of useful batterylife remain from the moment the low-batteryindicator is first displayed.

NOTE

When you see this low-battery display, usethe LIGHT as little as possible and replacethe batteries at the first opportunity (seepara 2-4a).

2 - 2 2

b. GENERAL FAULT INDICATOR

To indicate problems other than lowbatteries discovered during automatictesting, the general fault indicator (flashing0) is displayed.

If your radiac set displays the general faultindicator during operation or testing,immediately turn the unit OFF and send toorganizational maintenance for repair.

2-23

c. DELAYED GENERAL FAULT INDICATORIf the high-range detector becomes defective, thegeneral fault indicator (flashing 0) is notdisplayed immediately, as in the case of all otherelectrical faults. The fault indicator has beendelayed 3 minutes so that the operator has timeto observe the display and perform additionaltests.

If the display alternates between a high and lowreading, as shown below, this can be due to adefect in the high-range tube, or because thelow-range tube (provided the probe cover is open)is responding to beta radiation in excess of5cGy/hr. Because the high-range tube isinsensitive to beta radiation, the alternating high-and low-range readings will be normal in thiscase.

While the alternating indication is displayed, theoperator should close the probe cover to shieldthe low-range tube from beta radiation. If thealternating indication no longer occurs, no faultexists. If it continues, the high-range tube isdefective and the radiac set should be referred toorganizational maintenance.

2-24

2-7. NORMAL OPERATING PROCEDURES

a. READ DOSE RATE

NOTE

All you have to do to read dose rate is turnthe unit ON. After any operation, thedisplay always returns to dose rate.

Set PWR switch to ON.

NOTEEmission from radioactive materials israndom; it does not occur at a uniform rate.This causes fluctuations in the readingsdisplayed by the radiac set.

2 - 2 5

b. ILLUMINATE OR DARKEN DISPLAY

CAUTION

Over-use of the display light will drain thebatteries.

With PWR switch ON, turn light ON (up) orOFF (down).

c. READ ACCUMULATED DOSE

With PWR switch ON, press and hold A C C U MDOSE button to read accumulated dose, thenrelease button.

2 - 2 6

d. CLEAR ACCUMULATED DOSE

(1) Press and hold ACCUM DOSE and DOSEPER HR buttons

(2)With both these buttons down, press andhold CLR/TEST button

2-27

While all three buttons are down, theprevious accumulated dose clears. All threebuttons must be held until display reads:

When the three buttons are released thedisplay will show dose rate.

e. DISPLAY DOSE RATE ALARM SET POINT

(1)

(2)

(3)

Press and hold DOSE PER HR button

With button pressed, press and holdCLR/TEST button until alarm set pointfor dose rate is displayed in a flashingmode.Release both buttons.

2-28

While both buttons are released, displayflashes the dose rate alarm set point shownabove for 10 seconds, then reverts tonormal operation and displays dose rate.

f. DISPLAY ACCUMULATED DOSE ALARMSET POINT

(1)

(2)

(3)

Press and hold ACCUM DOSE button.

While holding button down, press and holdCLR/TEST button until the accumulateddose set point is displayed in a flashingmode.

Release both buttons.

2-29

The display flashes the accumulated dosealarm set point shown above for 10seconds, then reverts to dose rate.

g. TO SET ALARM MODE

(1) Set ALM switch to AUD (up) for audioalarm.

Alarm sounds when the dose rate oraccumulated dose points are exceeded, orwhen a fault occurs.

(2) Set ALM switch to VIS (down) for visualalarm.

2 - 3 0

(3)

Appropriate RATE or DOSE light flasheswhen the alarm set point is exceeded orwhen a fault occurs.

Set ALM switch to OFF (center) for noalarm.

h. SET DOSE RATE ALARM

Setting the dose rate alarm set point involvesentering the proper decimal point, range unit,(µGy/hr, cGy/hr, or Gy/hr), and first, second,and third digits into the radiacmeter memory.

NOTE

Read each of the steps in this procedurebefore trying to set the dose rate alarm. Forthe example below, a previous setting of1.00 cGy/hr is changed to 12.5 cGy/hr.

(1) SETTING DECIMAL POINTS AND UNITS

2-31

(a)

(b)

(c)

Press and hold DOSE PER HR button

While still holding the DOSE PER HRbutton, press and hold CLR/TEST untilprevious dose rate alarm set point is

displayed in a flashing mode, then releaseboth buttons.

Within 10 seconds, press and holdCLR/TEST button again until only

decimal point and unit indicator areflashing. Release CLR/TEST button.

Display remains the same as in step 2, butonly decimal point and unit indicator f lash:

2 - 3 2

(d) While decimal point and unit indicator areflashing, press and release the DOSE PERHR button .Repeat this until the desireddecimal point setting and units appear.

(e ) When ce r ta in t ha t t he des i red comb ina -t i on o f dec ima l po in t l oca t ion and un i t( µ G / h r , c G y / h r , o r G / h r ) a r e s h o w n ,

press and release CLR/TEST button.

Decimal point and uni ts are now locked intoset. The display wi l l f lash the f i rst digi t :

2 - 3 3

(2) SETTING FIRST DIGIT

(a)

(b)

Press and release DOSE PER HR button

until desired first digit appears. (The firstdigit in the example is the same as theprevious setting, so go to step b.)

When desired first digit appears, press andrelease CLR/TEST button .The first digit

is locked into set.

When the first digit has been locked intothe set, the display will flash the seconddigit:

2 - 3 4

(3) SETTING SECOND DIGIT

(a) Press and release the DOSE PER HRbutton Continue pressing and releasing

until the desired second digit appears (2 inthe example).

(b) When the desired digit appears, press and

release CLR/TEST button

The second digit is set and the displayflashes the third digit.

2 - 3 5

(4)

(a)

(b)

SETTING THIRD DIGIT

Press and release DOSE PER HR button Repeat until desired third digit appears

(5 in the example).

Press and hold CLR/TEST button .Thethird digit has been set and the new doserate alarm set point is displayed.

When CLR/TEST button isreleased, the unit then returns to dose rate.

2 - 3 6

i. SET ACCUMULATED DOSE ALARMSET POINT

To enter the accumulated dose alarm setpoint, refer to step h, above, for settingthe dose rate alarm set point, exceptsubstitute the ACCUM DOSE button forthe DOSE PER HR button in each step.

If the ALM switch is on VIS the DOSElight will flash instead of the RATE light.

NOTE

If the unit is installed in a vehicle and itis required to set the dose rate and/or dose

alarms for radiation outside the vehicle,follow the procedures given in paragraphs2-7h and 2-7i except that the alarm set

point values you set to must be divided bythe attenuation factor assigned to thevehicle in which the radiac set is installed.

For example, if the radiac set is installed in

an M-1 tank which has an attenuationfactor of 20.0 and you wish to set the doserate alarm so that it alarms at an external

2-37

j. READ ATTENUATION FACTOR

NOTE

The attenuation factor is different fordifferent vehicles.

M-1M 2 / M 3M-60M-113M-151M-577M-880M-1008M-998

20.09.1023.03.601.304.022.002.001.70

These factors are set by organizationalmaintenance. If the factor displayed onthe set in your vehicle in the followingoperation does not agree with the factorlisted for that type of vehicle, informimmediate supervisor.

2 - 3 8

(1) Press and hold ATTEN button.

(2) While holding ATTEN button, pressCLR/TEST button.

So long as both ATTEN and CLR/TEST buttons are pressed, the display indicates

the attenuation factor that has been set byorganizational maintenance.

When button is released, unit returns todose rate measured at the probe.

2-39

k. READ DOSE RATE OUTSIDE VEHICLE

NOTE

Emission from radioactive materials israndom; it does not occur at a uniformrate. This causes fluctuations in thereadings displayed by the radiac set.

(1) Press and hold ATTEN button.

(2) Release ATTEN button.

While button is pressed, display shows dosesensed at the probe mutiplied by theattenuation factor, as shown above.When the buttons are released, the displayreturns to dose rate at the probe.

2 - 4 0

I. TURN UNIT OFF

Set PWR switch to OFF.

Power to the set is turned off, but storedinformation, such as accumulated dose andalarm set points, is retained.

NOTEWhen batteries are removed from theradiac set memory is retained for only 5minutes.

2-8. OPERATION IN UNUSUAL WEATHER

At temperatures below -22°F (-30°C) it takessomewhat longer for characters to form on thedisplay. The radiac set automatically corrects forthis delay by sensing temperatures below -22°F (-30°C) and increasing the display time from every2 seconds to every 5 seconds. Operation of theset is normal otherwise.

2-41

2-9. OPERATION INSIDE SHELTERS

When monitoring inside shelters, fortifications,etc., (indirect technique) where radiation isattenuated when it reaches the probe, pre-operational tests are performed in accordancewith paragraph 2-4c, and normal operation is thesame as if the set was vehicle mounted (seeparagraph 2-7, procedures i and j).

Your unit commander determines the attenuatingfactor for the type of shelter in accordance withFM 3-3 and organizational maintenance sets thefactor.

2-10. EMERGENCY PROCEDURES

a. MISSING MAIN POWER BATTERIESIf the low-battery indicator comes on and threefresh batteries are not available, the set willoperate on two or a single battery, if necessary.However, operation with less than three batteriesconsiderably shortens battery life. If operating onless than three batteries, use the LIGHT as littleas possible and replace batteries at the firstopportunity (see paragraph 2-4a).

b. MEMORY LOSS

Memory may be lost due to depleted batteries orwhen batteries are removed from the radiac setfor more than 5 minutes. When this occurs andfresh batteries are installed, the number 8 willappear on the display during turn-on for about 2seconds and the alarm will sound if the ALMswitch is set to AUD.

2 - 4 2

When this condition occurs accumulated dose

and alarm set points will be lost and cannot berecalled. The operator can, however, reset new

alarm points (see 2-7h and 2-7i).

If you do not reset the alarm points, the setresponds with audible or visual alarm at 1.00

cGy/hr. for dose rate and 1.20 cGy. foraccumulated dose. (These points are setinternally and cannot be changed by theoperator.)

c. LOSS OF VEHICLE POWER

During vehicle-mounted operations, the batteriesare removed from the set and power is derivedfrom the vehicle-power supply (see paragraph 2-4a). If this supply does not operate or fails for anyreason, the radiac set will not function.

If you are certain that any apparent failure of theradiac set is caused by loss of vehicle power,operation can be partially restored to the set bydisconnecting it from vehicle power and installingbatteries. Under this condition the set worksproperly except for the intercom alarm and NBC(Nuclear/Biological/Chemical) system alarm,which do not function without vehicle power.

Carefully follow the steps below to remove the setfrom the mount and install batteries.

(1) EMERGENCY BATTERY INSTALLATION

(a) Be sure PWR switch is set to OFF.

2 - 4 3

(b)

(c)

Disconnect VEHICLE POWER PLUG fromVEHICLE POWER CONVERTERRECEPTACLE.

Loosen (do not remove) RETAINING SCREWSand raise TOP COVER.

2-44

(d) Disconnect CONVERTER CABLE PLUGfrom receptacle.

(e) Install batteries (see paragraph 2-4a,and connect receptacle cap.

2-45

(f)

(g)

Position coil cord connecting the probeto the radiacmeter to the back of the unitthrough the opening between the topcover and shelf.

Position radiacmeter squarely on shelfabove probe and center between LOCKINGLUGS.

2 - 4 6

(h) Close TOP COVER to position radiacmeteragainst POSITIONING TAB.

(i) Tighten the two RETAINING SCREWS.

(j) Perform operating tests (para 2-4d).

(k) At completion of mission, notify organi-zational maintenance of the loss ofvehicle power to radiacmeter.

2-47 /(2-48 Blank)

CHAPTER 3

OPERATOR MAINTENANCEINSTRUCTIONS

3-1. TROUBLESHOOTING PROCEDURES

This manual cannot cover all the problems thatcould happen when using the radiac set. Thetroubleshooting chart lists those problems thatare most likely to occur during the operation ormaintenance of the set. If one of thesemalfunctions occurs, perform the test orinspection and corrective action in the orderlisted. If a trouble is not listed or it is notcorrected after performing the recommendedcorrective action, notify you supervisor. SeeTable 3-1.

Table 3-1. TROUBLESHOOTING

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

1. DISPLAY IS BLANK WHEN UNIT ISTURNED ON (NOT VEHICLEMOUNTED).

Install new batteries (para 24-a).

3-1

Table 3-1. TROUBLESHOOTING(CONTINUED)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

2. DISPLAY IS BLANK WHEN UNIT ISTURNED ON (VEHICLE MOUNTED).

Check that all connectors are securelyconnected.

Tighten any loose connectors.

3. DISPLAY INDICATES NUMERAL 0WHEN UNIT IS TURNED ON.

Check that probe is securely connected toradiacmeter cable.

Connect probe to radiacmeter cable.

4. IMPROPER OR NO ALARMINDICATIONS DURING NORMALOPERATION.

Check alarm set points,

Reset alarm set points.

3-2. BATTERY REPLACEMENT.

See paragraph 2-4a.

3 -2

APPENDIX AREFERENCES

A-1. SCOPE

This appendix lists forms and publications thatare referenced in this manual or that containinformation applicable to the operation andmaintenance of the AN/VDR-2 Radiac Set.

A-2. FORMS

Equipment Inspection andMaintenance Worksheet . . . . . . . . DA Form 2404

Quality DeficiencyReport . . . . . . . . . . . . . . . . . . . . . . . . Standard Form

368

Recommended Changes toEquipment TechnicalManuals . . . . . . . . . . . . . . . . . . . . DA Form 2028

A-3. PUBLICATIONS

Consolidated Index ofArmy Publications andBlank Forms . . . . . . . . . . . . . . . . . .DA Pam25-30

Dry Battery Supply Data . . . . . . . . . . . . . . . SB-116

FSC Class 6135; DryBattery Management Data . . . . . . . . . . . SB 11-30

A-1

Procedures for Destruction of

Electronic Materiel toPrevent Enemy Use(Electronics Command) . . . . . TM 750-244-2

The Army MaintenanceManagement System(TAMMS)

. . . DA PAM 738-750

A-2

APPENDIX BCOMPONENTS OF END ITEM AND

BASIC ISSUE ITEMS LISTS

Section I. INTRODUCTION

B-1. SCOPE.This appendix lists components of end item andbasic issue items for the AN/VDR-2. This list willhelp you keep track of items required for safe andefficient operation.

B-2. GENERAL

The Compoents of End Item and Basic IssueItems Lists are divided into the followingsections:

a. Section II. COMPONENTS AND END ITEM.This listing is for informational purposes only andis not authority to requisition replacements.These items are part of the end item, but areremoved and separately packaged fortransportation or shipment. As part of the enditem, these items must be with the end itemwhenever it is issued or transferred betweenproperty accounts. Illustrations are furnished toassist you in identifying the items.

b. Section III. BASIC ISSUE ITEMS (BII).These are the minimum essential items requiredto place the AN/VDR-2 in operation, to operate it,and to perform emergency repairs. Although

B-1

shipped separately, packaged BII must be withthe AN/VDR-2 during operation and whenever itis transferred between property accounts. Theillustrations will assist you with hard to identifyitems. This manual is your authority torequest/requisition replacement VII, based onTOE/MTOE authorization of the end item.

B-3. EXPLANATION OF COLUMNSThe following provides explanation ofcolumns found in 10 tabular listings:

a. Column (1). ILLUSTRATION NUMBER(ILLUS. NO.). Indicates the number of theillustration in which the item is shown.

b. Column (2). NATIONAL STOCK NUMBER.Indicates the national stock number assigned tothe item. The national stock numbers in sectionIII are used for requisitioning basic issue items.

c. Column (3). DESCRIPTION. Indicates thenational item name and, if required, a minimumdescription to identify and locate the item. Thelast line for each item indicates the FederalSupply Code for Manufacturer (FSCM), inparentheses, followed by the part number.

d. Column (4). UNIT OF MEASURE (U/M).Indicates the measure used in performing theactual operation/maintenance function. Thismeasure is expressed by a two-characteralphabetical abbreviation (e.g., ea, in, pr).

e. Column (5). QUANTITY REQUIRED (QTYRQR). Indicates the quantity of the itemauthorized to be used with/on the equipment.

B-2

Section II. COMPONENTS OF END ITEM.

B-3

(1) (2) (3) (4) (5)NATIONAL DESCRIPTION

ILLUS. STOCK FSCM, AND QTYNO. NUMBER PART NUMBER U/M RQR

1 To be Radiacmeter ea 1Assigned (80063)

IM-243VDR-2

2 To be Probe ea 1assigned (80063)

DT-616/VDR-2

3 To be Pouch ea 1assigned (80063)

P/N A3085266Strap

4 To be (80063) ea 1assigned P/N A3085600

B-4

Section III. BASIC ISSUE ITEMS

(1) (2) (3) (4) (5)NATIONAL DESCRIPTION

ILLUS. STOCK FSCM, AND QTYNO. NUMBER PART NUMBER U / M RQR

Publication ea 2TM11-6665-251-10

NOTE

National stock numbers (NSNs) that aremissing have been applied for and will beadded to this TM by future changes/revision when they are entered in theArmy Master Data File (AMDF). Until theNSNs are established and published submitexception requisitions to: Commander, USArmy Communications - ElectronicsCommand, and Fort Monmouth. ATTN:AMSEL-MM-C-BE, Fort Monmouth, NewJersery 07703-5000 for the part required tosupport your equipment.

B-5/(B-6 Blank)

APPENDIX C

EXPENDABLE SUPPLIES ANDMATERIALS LIST

Section I. INTRODUCTION

C-1. SCOPE.This appendix lists expendable supplies andmaterials needed to operate and maintain theAN/VDR-2. These items are authorized by CTA50-970, Expendable Items (Except Medical, ClassV, Repair Parts, and Heraldic Items).

C-2. EXPLANATION OF COLUMNS.a. Column 1. ITEM NUMBER. Assigned to the

entry in the listing and referenced in thenarrative instructions to identify the material (forexample, “Use cleaning compound, Item 4, Appx

C”).

b. Column 2. LEVEL. This column identifies thelowest level of maintenance that requires thelisted item.

C—Operator CrewO—Organizational MaintenanceF—Direct Support MaintenanceH—General Support MaintenanceD-Deport Maintenance

c. Column 3. NATIONAL STOCK NUMBER.The National stock number assigned to the item,used to request or requisition the item.

C-1

d. Column 4. DESCRIPTION. Indicates thefederal item name and, if required, a description to identify the item. The last line for each item indicatesthe part number followed by the FSCM inparentheses, if applicable.

e. Column 5. UNIT OF MEASURE (U/M).Indicates the measure used in performing the actualmaintenance function. This measure is expressed by atwo-character alphabetical abbreviation (e.g., ea, in,pr). If the unit of measure differs from the unit ofissue, requisition the lowest unit of measure thatsatisfies requirements.

Section II. EXPENDABLE SUPPLIESAND MATERIALS LISTS

(1) (2) (3) (4) (5)NATIONAL DESCRIPTION

ITEM STOCK FSCM ANDNUMBER LEVEL NUMBER PART NUMBER U / M

1 C NSN Battery, Dry ea6135-01- BA-3090

063-1978

C-2

THE METRIC SYSTEM AND EQUIVALENTS

PIN: 063557 -000