TM 9 -6625 -2801 -14&P

T E C H N I C A L M A N U A L

O P E R A T O R ’ S , O R G A N I Z A T I O N A L ,

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

M A l N T E N A N C E M A N U A L ( I N C L U D I N G M A I N T E N A N C E R E P A I R P A R T S L I S T )

F O R

T E S T S E T ,

T E K T R O N I X

E L E C T R I C A L

T Y P E 1 5 0 2 - 1

N S N 6 6 2 5 - 0 4 - 0 8 4 - 3 8 5 5

T E K T R O N I X , I N C .

H E A D Q U A R T E R S , D E P A R T M E N T O F T H E A R M Y

A U G U S T 1 9 8 1

WARNING

WARNING

DRY CLEANING SOLVENT

Dry cleaning solvent or mineral spirits paint thinner is flammableand should not be used near an open flame. Fire extinguishersshould be provided when these materials are used. Use only inwell-ventilated areas.

Be extremely careful when working in the vicinity of batterieswhen the battery case is open. Do not use uninsulated tools.Do not wear rings or watches. Metal articles will, if allowedto contact connectors, cause severe arcing with possible injuryto personnel and damage to the battery.

TM 9-6625-2801-14&P

TECHNICAL MANUAL

NO. 9-6625-2801-14&P

HEADQUARTERSDEPARTMENT OF THE ARMY

Washington, DC, 20 August 1981

OPERATOR’S , ORGANIZATIONAL,

DIRECT SUPPORT, AND GENERAL SUPPORT

MAINTENANCE MANUAL (INCLUDING MAINTENANCE REPAIR PARTS LIST)

CHAPTERSection

CHAPTERSection

CHAPTERSection

REPORTING OF ERRORS

You can help improve this manual. If you find any mistakeor if you know of a way to improve the procedures, pleaselet us know. Mail your letter, DA Form 2028 (RecommendedChanges to Publication and Blank Forms) , or DA Form2028-2 located in the back of this manual direct to:Commander, U.S. Army Armament Materiel ReadinessCommand, ATTN: DRSAR-MAS , Rock Island, IL 61299.A reply will be furnished to you.

Page

1I.

II.

2I.

II.

3I.

FOR

TEST SET, ELECTRICAL

TEKTRONIX TYPE 1502-1*

Paragraph

INTRODUCTIONGeneral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Description . . . . . . . . . . . . . . ....... . . . .

OPERATING INSTRUCTIONSControls and Indicators . . . . . . . . . . . . . . . . . . .Operation . . . . . . . . . . . . . . . . . . . . . .......

SERVICE AND PREVENTIVE MAINTENANCEService on Receipt of Material . . . . . . . . . . . . . . .

II. Repair Parts, Special Tools and Equipment . . . . . .III. Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . .IV. Preventive Maintenance . . . . . . . . . . . . . . . . .

1-11-6

2-12-2

3-13-33-43-5

1-11-1

2-12-3

3-13-13-13-1

*NOTEThroughout the text, this is referred to as a Time Domain Reflectometer or a TDR. Thisis in lieu of the authorized Federal nomenclature.

i

TM 9-6625-2801-14&P

CHAPTER

Section

CHAPTERSection

CHAPTERSection

CHAPTERSection

CHAPTERSection

APPENDIX

4

5I.

II.III.

6I.

II.

7I.

II.

8I.

II.

9I.

II.III.

A

B

C

Paragraph Page

FUNCTIONAL ANALYSIS . . . . . . . . . . . . . . . . . . . . 4- 1 4-1

PERFORMANCE CHECKS/FAULT ISOLATIONGeneral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1 5-1Performance Checks . . . . . . . . . . . . . . . . . . . . . . . . 5-2 5-1Fault Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5 5-11

MAINTENANCE INSTRUCTIONSGeneral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1 6-1Maintenance Instructions . . . . . . . . . . . . . . . . . . . . 6-2 6-1

REPAIR INSTRUCTIONSGeneral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1 7-1Repair of TDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3 7-1

FINAL INSPECTIONGeneral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1 8-1Final Inspection Checks. . . . . . . . . . . . . . . . . . . . . 8-2 8-1

PREPARATION FOR SHIPMENT AND STORAGEPreparation for Travel.. . . . . . . . . . . . . . . . . . . . . 9-1 9-1Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2 9-1Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3 9-1

REFERENCES A-1 A-1

MAINTENANCE ALLOCATION CHART (MAC) B-1 B-1

MAINTENANCE REPAIR PARTS LIST C-1 C-1

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TM 9-6625-2801-14&P

LIST OF ILLUSTRATIONS

Figure

1-12-12-22-32-42-52-62-72-82-92-102-112-124-14-25-15-25-35-45-55-65-75-85-95-107-1C-1C-2

Number

1-11-22-15-16-18-1C-1C-2

Title

Time domain reflectometer, Tektronix 1502-1, cover removed. . . . . .TDR front panel controls and indicators . . . . . . . . . . . . . . . . . . . . . .Battery connector polarity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .230 Vac transformer wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Incident and reflecting pulses.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .X-Y output module strap.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Crt display of pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TDR display of RL vs ZO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Impedance nomograph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Open able . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ........Shorted cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Crimped cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Frayed cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Simplified block diagram.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Simplified sampling diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Pulse display . . . . . . . . . . . . . . . . . . . . . . . . . . . ...... . . . . . . . . .Jitter check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Position check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Rise time and fall time... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Power Supply board test points and adjustments . . . . . . . . . . . . . . .Pulse display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Loop gain adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .PC board location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Vertical amplifier/slow ramp board . . . . . . . . . . . . . . . . . . . . . . . . . .Output amplifier board fog adjustment . . . . . . . . . . . . . . . . . . . . . . . .Power supply board DC fuse location . . . . . . . . . . . . . . . . . . . . . . . .Replaceable electrical parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Standard accessories . . . . . . . . . . . . . . . .. . ..... .......

LIST OF TABLES

Title

Page

1-02-12-42-42-52-62-82-92-92-102-102-102-114-14-25-25-35-45-45-65-75-85-95-95-107-1C-4C-5

Page

TDR accessories storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ...2-2Tabulated data system... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...1-2TDR front panel controls and indicators . . . . . . . . . . . . . . . . . . . . . . . 2-2TDR troubleshooting procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . ...5-11Maintenance effort . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...6-1TDR final inspection checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...8-1Replaceable electrical parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..C-3Standard accessories . . . . . . . ............. ...... .. . . C-3

This technical manual is an authentication of the manufacturers’commercial literature and does not conform with the format andcontent specified in AR 310-3, Military Publications. Thistechnical manual does, however, contain available informationthat is essential to the operation and maintenance of theequipment.

iii/(iv blank)

TM 9-6625-2801-14&P

INSTRUCTIONS FOR REQUISITIONING PARTS

NOT IDENTIFIED BY NSN

When requisitioning parts not identified by National Stock Number, itis mandatory that the following information be furnished the supplyofficer.

1 - Manufacturer’s Federal Supply Code Number - 80009

2 - Manufacturer’s Part Number exactly as listed herein.

3 - Nomenclature exactly as listed herein, includingdimensions, if necessary.

4 - Manufacturer’s Model Number. Tektronix Type 1502-1

5 - Manufacturerfs Serial Number (End Item)

6 - Any other information such as Type, Frame Number, andElectrical Characteristics, if applicable.

7 - If DD Form 1348 is used, fill in all blocks except 4, 5,6, and Remarks field in accordance with AR 725-50.

Complete Form as Follows:

(a) In blocks 4, 5, and 6, list manufacturer's FederalSupply Code Number - 80009, followed by a colon andmanufacturer’s Part Number for the repair part.

(b) Complete Remarks field as follows:Noun: (nomenclature of repair part)For: NSN: 6625-01-084-3855Manufacturer: Tektronix, Inc.

P.O. Box 500Beaverton, Oregon 97005

Model: 1502-1Serial: (of end item)

Any other pertinent information such as FrameNumber, Type, Dimensions, etc.

v

TM 9-6625-2801-14&P

Figure 1-1. Time domain reflectometer, Tektronix1502-1, cover removed

1-0

TM 9-6625-2801-14&P

CHAPTER 1

INTRODUCTION

Section I.

1-1. Scope.

a. Purpose. The purpose of this man-ual is to provide information and instruc-tion for the direct support maintenanceof the Time Domain Reflectometer, Tek-tronix 1502.1 (hereafter referred to asthe TDR) including accessory equipmentand external test cable assemblies (seefigure 1-1),

b. Content Summary. This manualcontains the following information:

(1)

(2)tenance

(3)

(4)

(5)dures.

(6)

A description of the equipment.

Corrective and preventive main-instructions.

Checkout procedures.

Repair instructions.

Shipment and storage proce-

References to all related publica-tions (appendix A).

(7) Maintenance allocation chart

GENERAL

defining maintenance level responsi-bilities (appendix B).

(8) Maintenance repair parts list(appendix C).

1-2. Forms and Records. Refer to TM 38-750 for instructions on the use ofappropriate forms, records and reports.

1-3. Calibration. Calibration proceduresfor the TDR are provided in TechnicalBulletin TB 11-6625-2860-35.

1-4. Destruction of Material to PreventEnemy Use. For information on destruc-tion of materiel to prevent enemy use re-fer to TM 750-244-2.

1-5. Reporting Equipment ImprovementRecommendations (EIR). EIR’s will beprepared using SF 368, Quality DeficiencyReport (QDR). Instructions for preparingEIR’s are provided in TM 38-750, TheArmy Maintenance Management System(TAMMS). EIR’s should be mailed directlyto Commander, U.S. Army Armament Mat-eriel Readiness Command, Attention:DRSAR-MAO, Rock Island, IL 61299. Areply will be furnished directly to you.

Section II. DESCRIPTION AND DATA

1-6. Description.

a. General. The Tektronix 1502-1 is aportable Time Domain Reflectometer whichuses radar principles to test cables andprovides a visual display of cable faults.The test pulses are transmitted via theCABLE output jack. Reflections are re-ceived at the same jack and displayed onthe cathode-ray tube (crt).

Calibrated distance controls allow an op-erator to examine up to 100 feet of cablewith segments as small as 1 foot displayedhorizontally across the 10-division crtscreen. Low-loss cables as long as 2000feet may be examined at 100 feet per divi-sion or 200 feet per division. The horizon-tal crt scale is calibrated directly in dis-tance units from 0. 1 foot per division to200 feet per division in a 1-2-5 sequence.

1-1

TM 9-6625-2801-14&P

A 3-digit, direct reading dial indicatesthe distance to any cable discontinuitywhen the dial is used to horizontally posi–tion the discontinuity’s reflection to a crtreference line.

Accessories Not Stored in Cover

Accessory Tektronix partnumber

b. Description. 1 TDR Slide Rule 003-0700-00

1 TDR Application Note #1 062-1538-00

1 X-Y Output Module 016-0606-00

1 Instruction Manual 070-1792-00

(1) Main case. The TDR is a rug-gedized portable instrument that can beused in the field as well as in the labora–tory. The requirements for a Type II,Class 2, Style A instrument as specifiedin MIL-T-28800 were used as a guidelinefor the environmental specifications. TheTDR has a ruggedized case that providesprotection when the instrument is storedin exposed areas.

1-7. Tabulated Data. The characteristicsgiven in table 1-2 apply after the instru-ment has been calibrated and will performto the requirements given in Chapter 5.

Table 1-2. Tabulated Data System

(2) Accessories. When the instrumentis not being used, the accessories, including

Characteristics Performance

the Operators manual, may be packed inthe front of the instrument. Table 1-1

Termination 50 within ±2%.

Pulse AmplitudeInto 50 Load 225 mV Nominal.

indicates which accessories may be placedin the cover of the TDR.

Table 1-1. TDR Accessories Storage Vertical System

Accessories Stored in Cover Deflection Factor(7 steps, 1-2-5sequence) 5 /div to 500

/div.

Accuracy Within ±3%.

Gain (screwdriver At least 3.5:1control) from calibrated

point.

Tektronix partsAccessories number

1 50 BNC Terminator 011-0123-00

1 Precision 50 Cable 012-0482-00

1 Viewing Hood 016-0297-00

1 Operators Manual 070-1790-00 Displayed Noise ±5 or less,NOISE FILTERswitch “Out”.

1 BNC ConnectorFemale-to-Female 103-0028-00

Low Noise Operation ±2 or less,NOISE FILTERswitch “In”.

2 Replacement Fuses(for front panel)For 115 VacOperation

orFor 230 VacOperation (Option 6)

159-0029-00Horizontal System

Distance Controls 0 to 2000 feettotal.

159-0054-00

161-0066-001 Power Cord

1 Filter, Mesh (crt) 378-0055-00

1-2

TM 9-6625-2801-14&P

Characteristics PerformanceTable 1-2. Tabulated DataSystem - Continued

O T H E R - V A R Vp/Vair = 0.55 to 1Horizontal System - Continued

Characteristics PerformanceAccuracy Within ±2%.

RecordersDistance Dial

At X1 MultiplierRange 0 to 100 feet.

External RecorderInterface for X-YRecordersHorizontal

AccuracyI

Within ±2%, ±0.5foot. 0.1 V/div;

(source impedance10 K ).At X1 Multiplier

Range 0 to 1000 feet.Vertical 0.09 to 0.13 V/div

adjustable (source)impedance 10 k

Accuracy Within ±2 %, ±1Digit.

FEET/DIV ControlAt X.1 MultiplierRange To 20 feet/div

Pen LiftMode 1Source Vs = 5 V Nominal

with Rs = 10 k

< 10 mA (V out< 0.5 V).

Scales(8 steps,1-2-5 0.1 foot/div to 20sequence) feet/div.

Sink

Mode 2 (invertedMode 1)Source

Accuracy(All scale Vs = 5 V Nominal

with Rs = 10 k settings) Within ±2%.

(With scaleset at 20ft/div) Within ±1%

At X1 MultiplierRange To 200 feet/div.

Scales(8 steps,1-2-5 1 foot/div to 200sequence) feet/div.

AccuracyAll scalesettings Within ±2%.

200 ft/divscale Within ±1%.

Dielectric Scales

Sink < 0.5 mA (V out<0.6V).—

Power System

117 Vac ±20%, 48to 410 Hz; fusedat 0.3 A.234 Vac ±20%, 48to 410 Hz; fusedat 0.15 A.

Line Voltage

Battery Pack(C size, 9 cell)Operation(+20oC to +25°Ccharge and dis–charge tempera-ture)

At least 5 hours.

SOLID PTFE V p/ Vair = 0.70

SOLID POLY V p/ Vair = 0.66 16 hoursFull Charge Time

1-3

TM 9-6625-2801-14&P

Table 1-2. Tabulated Data - Continued

Power System - Continued

Characteristics

Typical ChargeCapacity

Charge Tempera-ture

0 oC

+20oC to +25°C

+40oC

Description

Discharge Tempera-ture

Physical Characteristics

Characteristics Description

Weight with panel cover 18 poundsand accessories

Without panel cover 16 poundsand accessories

Height 5.0 inches

Width with handle 12.4 inches

Without handle 11.8 inches

Depth including panel 16.5 inchescover

65% 100% 85% Handle extended 18.7 inches

40% 65% 55%

1-4

TM 9-6625-2801-14&P

CHAPTER 2

OPERATING INSTRUCTIONS

Section I. CONTROLS AND INDICATORS

2-1. Front Panel Controls and Indica- adjustment follows. A description of thetors. A brief description of the pur- controls of the plug-in module is alsopose of each front panel connector, included. Refer to figure 2-1 for theirpushbutton, control, and screwdriver location.

Legend for fig. 2-1:

1.2.3.4.5.6.7.8.9.

CABLE connectorFOCUS controlINTENSITY controlPOSITION control /DIV switchPOWER switchGAIN adjustmentNOISE FILTER switchBATTERY meter

11.12.13.14.15.

16.17.18.

ZERO REF SET controlmultiplier switchDISTANCE controlFEET/DIV switchCABLE DIELECTRIC switches andcontrolRECORD/CAMERA switchAC LINE fusesX-Y OUTPUT MODULE

10. ZERO REF CHECK switch 19. External

Figure 2-1. TDR front panel controls and

chart recorder controls

indicators

2-1

TM 9-6625-2801-14&P

Table 2-1. TDR Front Panel Controlsand Indicators

Figure 2-1index no

1

2

3

4

5

6

7

8

Control orindicator

CABLE

FOCUS

INTENSITY

POSITION/FINE

/DIV

POWER

GAIN

NOISEFILTER

Function

BNC Connector-delivers 110 psrisetime pulse tothe test cable andreceives the re–fleeted returnpulse.

Adjusts the focusof the crt elec–tron beam.

Controls thebrightness of crtdisplay.

Controls verticalposition of the crtdisplay. Theouter control is acoarse adjust–ment and theinner control isa fine adjustment.

Selects the verti-cal deflectionfactor--5 /divto 500 /div(5-2-1 sequence).

Push-pull, off-onswitch (pull foron) – does notaffect the batterycharging circuit.

Screwdriver ad-just to set thegain of the verti-cal amplifier.

Reduces displayednoise. Displayrate is reduced bya factor of 10.

Figure 2-1index no.

9

10

11

12

13

Control orindicator

B A T T E R Y

ZEROREFC H E C K

ZEROREFSET

MULTI-PLIER

DISTANCE

Function

Meter to indicatethe relative chargeof the power pack.

Momentary contactPushbutton. Whenpushed, checksthe horizontal lo-cation of the inci–dent pulse on thecrt when the DIS-TANCE dial isbeing used.

horizontal pulseposition controlfor crt display.Sets the incidentpulse edge to avertical referenceline of the crtwhen the DIS-TANCE dial is at000 or the ZEROREF CHECK but-ton is pushed.

Two-positionswitch (red con–trol) for X.1 orX1 multiplier.Affects both theDISTANCE dialand the FEET/DIV control.

Inicates the dis-tance from theTDR to the pointon the cable wherethe display win-dow begins. Tworanges: 100 feetat X.1 or 1000feet at X1. Dis-abled when theFEET/DIV is at200 (FIND).

2-2

TM 9-6625-2801-14&P

Table 2-1. TDR Front Panel Controlsand Indicators – Continued

Figure 2-1index no

14

15

16

Control orindicator

FEET/DIV

C A B L EDIELEC-TRICSOLIDP O L Y

SOLIDPTFE

O T H E RV A R

R E C O R D /C A M E R A

Function

Selects the hori-zontal deflectionfactor:X1=1 - 200 ft/div.

X.1=0.1 - 20ft/div.

Three pushbuttonsand a screwdriveradjust. Selectsthe proper velocityof propagation.VAR from 0.55 to1.0 when theOTHER pushbuttonis pressed. Fullycw if for air die–lectric. VAR con-trol has referencemarks every 30°to indicate rela-tive propagationconstants.

Two-position leverswitch; pushed upand then released,it initiates X-YRecorder or a

Figure 2-1index no.

17

18

19

Control orindicator

AC LINEFUSES

X-YO U T P U TM O D U L E

X, Y,and PENLIFT

Function

Chart Recorder;pushed down, itfloods the crt -during retrace todisplay graticulefor photography.

Protection fusesfor line powerand battery charg-ing circuits (0.3A fuses for 115Vac; 0.15 A fusesfor 230 Vac).

The standard plug-in module for theTDR. Used todrive an externalX-Y Chart Re-corder.

Six front paneljacks used fordriving an ex-ternal X-Y re-corder. X jacksare for horizon-tal drive. Y jacksare for verticaldrive. PEN LIFTjacks are for pencontrol.

Section II. OPERATION

2-2. Operating Power Selection.

Be extremely careful when workingin the vicinity of batteries when thebattery ease is open. Do not useuninsulated tools. Do not wearrings or watches. Metal articles will,if allowed to contact connectors,cause severe arcing with possibleinjury to personnel and damage tothe battery.

When substituting a dc powersupply or external battery forthe battery pack, be sure thepolarity is correct (see figure2-2).

2-3

TM 9-6625-2801-14&P

Figure 2-2. Battery connector polarity

a. Battery Connections. A 12 Vdcpower supply may be substituted for theTDR battery pack by removing the packfrom the unit and connecting the powersupply to the terminals inside the batterypack compartment.

The power pack can be stored at anytemperature between -40oC and +50°Cwith the battery cells either fully orpartially charged. The self-dischargerate of the cell increases with increasedtemperature. A fully charged batterywill lose about 50% of its charge in 3 to 4months if stored at +20°C to +25°C.Therefore, the battery pack should becompletely recharged before using if ithas been stored without power suppliedto its charging circuit for more than amonth.

When the TDR is wired for 230Vac, be sure that the two frontpanel fuses are changed to 230 V,0.15A slow-blow fuses and theproper plug is installed on theac cable.

b. 230 Volt Operation. The batterycharger is factory wired for 115 Vac or230 Vac if Option 6 is ordered. Thestandard 115 Vac unit can be changed to230 Vac operation by rewiring the linetransformer. Figure 2-3 shows the pro-per wiring configuration for 230 V opera-tion.

2-3. Turn-on Procedures.

NOTE

If crt displays no signal, checkfault isolation paragraph 5-6.

Figure 2-3. 230 Vac transformer wiring

a. Preparation.

(1) To gain access to the front panel,pull the two side latches forward and re-move cover. Using the handle of theTDR as a stand, position it to raise theunit to a convenient operating position(figure 1-1).

(2) The battery pack is fully chargedin 16 hours when connected to an ac powersource and the unit is switched off. TheTDR may be operated while the batterypack is charging; however, the chargingtime will increase. The batteries will notovercharge if the charger is left on long-er than 16 hours. Therefore, the TDRmay remain connected to an ac sourcewithout damaging the batteries. Approxi-mately once a month or every 15 -charge–discharge cycles, the batteries should becharged for approximately 24 hours.

2-4

TM 9-6625-2801-14&P

Approximately 30 minutes of operatingtime can be expected from a 1-hour partialcharge. To avoid reverse charging, thefull 16 hour charge should be completedin preference to a partial charge when-ever possible.

b. Control Settings (TDR).

(1) Set front panel controls asfollows:

F O C U SINTENSITYZERO REFPOSITION /DIVDISTANCEFEET/DIVX 1 - x 1CABLE DIE-LECTRIC

P O W E R

MidrangeFull rangeFully cwMidrange5000001X 1SOLID POLY

O N

(2) Adjust INTENSITY and FOCUScontrols for a clear bright trace.

(3) Adjust POSITION controls to settrace 2 divisions below horizontal center–line.

(4) Attach precision 50 cable (012-0482-00) to CABLE connector (stored incover).

(5) Turn ZERO REF SET button ccwuntil incident pulse edge is located on avertical reference line. The incidentpulse edge is the initial rise of the steppulse. The vertical reference line may beany line you choose from center line toleft side of crt graticule. An arrow inthe second vertical line indicates acommonly used reference line.

NOTE

The reflected pulse from the openend of the 50 cable should ap-pear three horizontal divisions toright of reference line. Open endof cable is indicated by start of asecond rise in trace (see figure2-4).

Figure 2-4. Incident and reflected pulses

(6) Turn ZERO REF SET buttonthroughout its range to see that the inci–dent pulse edge can be set on any verti-cal graticule line. Set incident pulseedge on vertical reference line.

(7) Set DISTANCE dial to 050 andcheck that top of step (open cable re–flection) is displayed.

(8) Press ZERO REF CHECK buttonand check that incident pulse edge re-turns to vertical reference line of grati-cule. Reset DISTANCE dial to 000.

(9) Change /DIV to 50 and adjustPOSITION controls so top of incidentpulse is on horizontal centerline.

(10) Press NOISE FILTER pushbuttonand check for a reduction in displayednoise as well as a reduction in scan rate.Reset /DIV to 500, and release (bydepressing a second time) NOISE FILTERbutton.

(11) Press and hold CAMERA switch.Note crt display; entire crt should beflooded on retrace to illuminate graticulewhen taking photographs. ReleaseCAMERA switch.

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TM 9-6625-2801-14&P

(12) Lift up and hold RECORD switch.Check that bright spot appears at leftedge of crt.

(13) Release RECORD switch. Slowscan of spot will trace displayed wave-form. When scan is complete TDR willautomatically return to its normal modeof scanning.

c. Control Settings (Accessories).

NOTE

The X-Y OUTPUT MODULE iswired for either a positive ornegative pen lift signal. Be-fore using the X-Y OUTPUTMODULE , be sure that the penlift circuit on the etched cir-cuit board is properly connected.Figure 2-5 shows the properconnection for either a positiveor negative pen lift signal.

Figure 2-5. X-Y output module strap

(1) If not already in place, installX-Y OUTPUT MODULE into its compart-ment on front panel of TDR.

(2) Connect X, Y, and PEN LIFTinputs of recorder to correspondingjacks of X-Y OUTPUT MODULE.

(3) Position and hold RECORD/CAMERA switch to RECORD to preparefor recording.

(4) To position stylus at desiredposition on paper, adjust STYLUS POSI-TION screw while RECORD/CAMERAswitch is in the RECORD position.

(5) Release RECORD/CAMERA toprecede with recording. Chart recordcircuits automatically shut off when re-cording is completed.

NOTE

In evaluating a graph, the dis-tance between two dark hori-zontal lines corresponds to onevertical division of the crt dis–play with respect to the DIV setting; the distance be-tween two dark vertical linescorresponds to one horizontaldivision of the crt display withrespect to the FEET/DIV setting.

d. Use of Accessories.

(1) Mesh Filter for the crt. A meshfilter is provided with the TDR which.makes viewing of the crt easier when theunit is being used in the sunlight. Thisfilter is placed over the crt by sliding itonto the slots of the crt bezel.

(2) Viewing Hood. The viewing hoodprovides shading for the crt and can beinstalled over the crt by sliding it downover the crt bezel sides. The mesh filtermust be removed before the viewing hoodwill connect to the crt bezel.

(3) Using a Camera with the TDR.If a Camera Adapter (Tektronix PartNumber 016-0327-00) is attached to thecrt bezel of the TDR, a C–30A/31 cam–era can be used to take photographs ofthe crt display. To obtain graticuleillumination, the RECORD/CAMERAswitch must be pushed down and heldwhile the photograph is being taken.After the trace is completed the entire crtis flooded to provide a light backgroundto allow the dark graticule to appear inthe photograph.

2-6

2-4. Cable Testing.

Do not connect live circuit cablesto the input of the TDR. Volt-ages in excess of 5 volts can dam-age the sampling gate or tunneldiode.

Bleed cables before connectingthem to the TDR to remove staticcharge from them. The 50 ohmtermination and BNC adaptersupplied may be used to bleedany cable charge.

When testing antennas, be surethat you are not close to trans-mitters that can be keyed at theantennas receiving frequency.Keying of transmitters in closeproximity can cause damage tothe TDR.

a. Connecting a Cable for Testing.

(1) Connect cables to be tested bythe TDR to the BNC connector (CABLE)on the front panel. Use connector/adap-ter as required.

(2) Adjust FOCUS and INTENSITYcontrols for a sharp and bright displayon the crt.

b. Locating a Discontinuity in a Cable.

The DISTANCE dial and the FEET/DIVcontrol make it possible to evaluate cablesas long as 2000 feet. The entire lengthcan be displayed directly on the crt ifdesired. If a chart recorder is used,only that portion of the trace seen on thecrt will be recorded on the graph. Tocheck cables using the crt, proceed asfollows:

(1) Set crt display window so it islonger than the cable under test by set-ting the FEET/DIV control and the X1/X.1 control, For example, if the cable is

150 feet long, setand the multiplier

TM 9-6625-2801-14&P

the FEET/DIV to 200at X.1.

NOTE

Use the X.1 multiplier wheneverpossible to lessen the effects ofjitter.

(2) Measure the distance betweenthe incident pulse rise and the reflectedpulse rise.

NOTE

The distance from the samplingbridge to the CABLE connector(2. 5 inches) should be taken in-to account when measuringcables less than 2 feet in length.

(3) To more accurately locate thediscontinuity, set the FEET/DIV controlto a lower setting. (The reflectedpulse does not need to be in the displaywindow). Push the ZERO REF CHECKbutton and adjust the ZERO REF SETcontrol so that the incident pulse rise isset at a convenient vertical referencegraticule line. The ZERO REF SETcontol may have to be readjusted whenchanging the FEET/DIV control.

NOTE

Always set the incident and re-flected pulse to the 10% points oftheir amplitude (see figure 2-6).

(4) Turn the DISTANCE dial clock-wise until the reflected pulse is locatedon the reference graticule line. Thereading on the DISTANCE dial times themultiplier gives the length from theCABLE connector to the end of the cable(or to the discontinuity).

N O T E

When checking cables longerthan 1000 feet, adjust the DIS-TANCE dial until the reflectedpulse reaches the right-hand

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TM 9-6625-2801-14&P

edge of the graticule, thenadd the graticule display dis-tance to that on the DISTANCEdial for the total length. Thereading of the DISTANCE dial,plus the number of divisions(from the reference line) acrossthe graticule times the FEET/DIV setting gives the totallength of the cable. Rememberthat in the 200 FEET/DIV set-ting the DISTANCE dial is in-operative.

Figure 2-6. Crt display of pulse

(5) The CABLE DIELECTRIC push-buttons allow the TDR to accurately lo-cate discontinuities in cables of variousrelative propagation velocity constant(Vp). The SOLID POLY button is cali-brated to check solid polyethylene die-lectrics which have a Vp of 0.66. TheSOLID PTFE button is calibrated to checksolid polytetrafluoroethylene (Teflon)which has a Vp of 0.70. The OTHERbutton is variable from 0.55 to 1.00 andis controlled by the screwdriver adjust–ment control VAR. When this screwdrivercontrol is turned to the fully clockwiseposition, it is calibrated for air dielectricswhich have a Vp of 1.00. If all three ofthe CABLE DIELECTRIC buttons arereleased, a default condition leaves theinstrument calibrated for air dielectrics(Vp) = 1.00).

c. Evaluating a Discontinuity. The /DIV control determines the verticaldeflection that can be seen on the crt orrecorded on a graph if a chart recorderis used. This control is calibrated tomeasure the ratio of the reflected signalamplitude to the incident signal amplitudein rho ( ), which is called the voltagereflection coefficient. Rho ( ) is themeasurement of reflected signal amplitudeand can be used to determine the im–pedance of a discontinuity. Note that noreflection is obtained from a cable thathas no discontinuities if the cable is ter-minated with its characteristic impedance.If a cable has an open, i.e., a break(infinite impedance), the reflected stepamplitude is +1 ; and if a cable has ashort (zero impedance), the reflectedstep amplitude is -1

(1) Figure 2-7 shows the two partsof a TDR display labeled to identify theincident and reflected voltage signals.When =0, the transmission line is ter-minated by a resistance equal to itscharacteristic impedance (Z0) which, inthis case, is 50 . When equals +1,the transmission line load is a short. Ifthe line is terminated by RL > 50 is positive and if the line is terminated byRL < 50 is negative.

(2) Figure 2-8 is a chart for conver-ting reflected pulse amplitude to impe-dance. Rho is dependent on the charac-teristic impedance, Z0, of the cable undertest and the load (or the impedance ofthe discontinuity), RL, on the cable.Therefore, a can also be defined as:

d. Typical Cable Problems. A few ofthe cable problems that can be analyzedwith the TDR include opens, shorts, pin-holes in the cable shield, opens in theshield, kinks in the cable, mismatchedconnectors, and corroded connectors.

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Figure 2-7. TDR display of RL vs ZO

Figure 2-8. Impedance nomograph

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Figures 2-9 through 2-12 show typicalexamples of these problems.

Figure 2-9. Open cable

e. Checking Cables with Other than50 Ohms Impedance.

(1) Cables with a characteristicimpedance other than 50 can be evalu-ated by adjusting the GAIN control(screwdriver adjust) to correct the re-flected pulse for +1 at the open end ofa cable. When the GAIN is changed, theincident pulse will no longer be 1 .

(2) To reset the GAIN for an impe-dance other than 50 , either connectan impedance–matching adapter (50 to75 , 50 to 93 50 to 125 etc.) to theCABLE connector and connect a shortlength of cable (with impedance the same

Figure 2-10. Shorted cable

as the adapter, i.e., 75 125 etc.)to the adapter or connect the cable to betested to the CABLE connector. With the /DIV control set at 500, position thetrace on the graticule so that the displayof the cable appears in the display. Now Figure 2-11. Crimped cable

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adjust the GAIN control so that the openend display (reflected pulse) is set 2divisions above the cable display (hori-zontal centerline). This sets the re-flected pulse to +1 from the character-istic impedance.

NOTE

If an impedance adapter is notused, secondary reflectionswill re–appear as discontinu-ities beyond the open end ofthe cable.

Figure 2-12. Frayed cable

2-11/(2-12 blank)

TM 9-6625-2801-14&P

CHAPTER 3

SERVICE AND PREVENTIVE MAINTENANCE

Section I. SERVICE UPON RECEIPT OF MATERIAL

3-1. Unpacking and Inspection. When the TDR isreceived, it will be packed in a corrugated card-board carton. Inside packing and re-enforcement isalso fabricated from corrugated cardboard. Gainaccess to the TDR by carefully cutting the sealingtape on top of the carton, open carton, remove thetop packing, and withdraw TDR from carton,Carton should be stored for future use in reship-ping. Visually inspect the TDR for

damage. Release cover and inspect frontpanel and controls for damage. Open in-side cover. Remove, unwrap and checkfor all items listed in table 1-1 and in-spect all items for damage.

3-2. Checkout Procedures. Performprocedures given in paragraphs 2-3 aand b to ensure the equipment is in op-erational condition.

Section II. REPAIR PARTS , SPECIAL TOOLS AND EQUIPMENT

3–3. Repair Parts. Repair parts arelisted in Appendix C of this manual.

Section III. LUBRICATION

3-4. General. This equipment does notrequire periodic lubrication.

Section IV. PREVENTIVE MAINTENANCE

Dry cleaning solvent or mineralspirits paint thinner is flammableand should not be used near anopen flame. Fire extinguishersshould be provided when thesematerials are used.ventilated areas.

3-5. General. Preventive maintenanceconsists of cleaning, visual inspection,etc. Preventive maintenance performedon a regular basis will help improve thereliability of the instrument. The se-verity of the environment to which theTDR is subjected determines the fre-

Use only in well quency of needed maintenance. A con-venient time to perform preventivemaintenance is preceding recalibration ofthe instrument.

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3-6. Cleaning.

a. General. Accumulation of dirt inthe instrument can cause overheating andcomponent breakdown. Dirt on compo-nents acts as an insulting blanket andprevents efficient heat dissipation. Italso provides an electrical conductionpath.

b. Interior. The TDR is constructedin a manner that protects the interior ofthe instrument from dust.

NOTE

When the cabinet is removed,the watertight integrity may becompromised. See the instruc-tions (in this section) on remov-ing and replacing the cabinet.

Therefore, the interior of the TDRshould not require cleaning unless theunit has been left with the front coverremoved and the plug–in compartmentempty. The best way to clean the in-terior is to blow off the accumulated dustwith low–pressure air. Remove any dirtthat remains with a soft brush or a clothdampened with a mild detergent andwater solution. A cotton-tipped appli-cator is useful for cleaning in narrowspaces on circuit boards.

Avoid the use of chemical clean-ing agent which might damagethe plastics used in this instru-ment. Avoid chemicals whichcontain benzene, toluene, xy–lene, acetone or similar solvents.

rinsed with clear water. Loose dust ac-cumulated on the front panel is bestremoved with a small brush or a softcloth dampened with a mild detergent andwater solution. Abrasive cleaners shouldnot be used on the front panel.

d. CRT Implosion Shield. The face ofthe crt can be cleaned by using isopropylalcohol applied and wiped very gentlydry with lens paper (NSN 6640-00-559-1385).

3-7. Servicing battery. The batterypack should be inspected every twomonths. The entire battery pack shouldbe replaced if venting or corrosion hasoccurred.

3-8. Water-tight Seals. The TDR is pre-pared to be operated in any weather(rain, snow, dust, etc.). To preventmoisture and dust from getting inside theinstrument, special seals are used aroundthe pushbuttons, crt, power switches,and rotary controls. Removal of any ofthe components on the front panel willrequire special resealing procedures toretain their water–tight integrity.

3-9. Calibration. To ensure accuratemeasurements, check the calibrationevery 120 days. Refer to CalibrationProcedure Technical Bulletin for TimeDomain Reflectometer, Tektronix Type1502-1, TB 11-6625-2860-35 for calibra-tion procedures.

c. Exterior. The cabinet exteriorcan be washed with soap and water and

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TM 9-6625-2801-14&P

CHAPTER 4

FUNCTIONAL ANALYSIS

4-1. Simplified Circuit Analysis. TheTDR uses radar principles to check cableconditions. The pulser circuits transmitthe pulses down the cable under test,and the sampler circuits sample the echosand provide the vertical signal for dis-play on the crt.

a. Pulser. The pulser is basically atunnel diode in a 50 ohm strip line (cavi-ty). It contains all biasing and timingcircuits required for operation of tunneldiode CR1703.

b. Sampling.

(1) Sequential equivalent-time samp-ling is used to develop a display (seefigure 4-1). Two ramps are generated,a fast ramp and a slow ramp. The fastramp is compared to the slow ramp or afixed reference to generate trigger pul-ses for the sampler and the pulser respec-tively. These comparisons are made bythe pulser and sampler comparators.

Figure 4-1. Simplified block diagram

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TM 9-6625-2801-14&P

(2) A short time after the pulsertransmits the step pulse into the cableunder test, depending on the amplitudeof the slow and fast ramps, a samplingtrigger from the sampler comparatorcauses the sampler to sample–and–holdthe voltage level appearing at that time.This voltage is taken at the point wherethe sampler is connected to the 50 ohmstrip line. This voltage sample is ampli-fied and sent through the vertical ampli-fiers to the crt.

(3) The slow ramp generator pro-vides the horizontal sweep for the crt

provides a display of the sampled value.Ensuing sampling triggers taken laterduring the next fast ramp time, causeadditional samples to be displayed next tothe first one, until a line of very shortdashes is formed across the crt, appear-ing as a solid line (figure 4-2).

c. Chart Recorder.

(1) The amplified vertical and rampsignals are also sent to X–Y interfaceconnectors. These signals, along with apen lift control signal, provide the in-formation for driving external X-Y record-

and, combined with the vertical sample, ers.

Figure 4-2. Simplified sampling diagram

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TM 9-6625-2801-14&P

CHAPTER 5

PERFORMANCE CHECKS/FAULT ISOLATION

Section I. GENERAL

5-1. Introduction. This chapter provides any test equipment. Performing thedetailed performance checks for the TDR. checks will also identify a fault presentPerformance checks may be made without in the

Section II. PERFORMANCE

e q u i p m e n t .

CHECKS

5-2. Preparation for Performance Checks.

a. Ensure that a battery is installed inthe TDR.

b. Connect TDR to ac power source.

c. Pull the POWER switch to turn theunit on. BATTERY meter will indicatethe relative level of charge on the batterypack. If the battery pack is fully charged(charged for 16 hours), the BATTERYmeter needle will be approximately at thetop mark on the meter.

5– 3. Performance Checks.

a. Perform procedures given in para-graph 5-2 and then set front panel con-trols as follows:

INTENSITY Fully cwZERO REF Fully cwPOSITION Midrange /DIV 500DISTANCE 000NOISE FILTER OutFEET/DIV 200MULTIPLIER X1CABLE DIELECTRICSOLID POLY InSOLID PTFE OutOther OutV A R Fully cw

b. Preset the POSITION and GAIN con-trols so the trace is on screen and the

amplitude is approximately 4 divisions.Adjust the FOCUS and INTENSITY con-trols for a clear, bright trace.

FEET/DIV 200MULTIPLIER X1CABLE DIELECTRICSOLID POLY InSOLID PTFE OutOther OutV A R Fully cw

b. Preset the POSITION and GAINcontrols so the trace is on screen and theamplitude is approximately 4 divisions.Adjust the FOCUS and INTENSITY con-trols for a clear, bright trace.

c. Adjust the GAIN control so that thetotal amplitude of the display is exactly 4divisions. If incorrect, forward TDR todepot for repair.

d. Set FEET/DIV control to 2 andMULTIPLIER to X1.

e. Turn the ZERO REF SET controlcounterclockwise to locate the pulse atcenter screen. Check for correct wave-form as shown in figure 5-1a. If thedisplay is not correct, forward TDR todepot for repair.

f. Connect the precision 50 terminator(Tektronix Part No. 011-0123-00) to theCABLE connector. Turn the GAIN controlfully counterclockwise and note the

5-1

TM 9-6625-2801-14&P

amplitude of the pulse. Turn the GAIN tude with the GAIN control fully counter-control fully clockwise. The amplitude clockwise. (Adjust the POSITION controlshould be 4 times greater than the ampli- as necessary.)

Figure 5-1. Pulse display

g. Set the /DIV control to 200, theFEET/DIV control to 20 and the MULTI-PLIER control to X1.

h. Adjust the ZERO REF SET controlso that the pulse is at the center of thescreen. Adjust the GAIN control for ex-actly 5 divisions of amplitude.

i. Change the /DIV control to 500and remove the 50 terminator. The amp-litude of the pulse must be 4 divisions±0.12 division (±0.6 minor division). If

not, forward the TDR to depot for repair.

j. Set the FEET/DIV control to 1 andadjust the ZERO REF SET control so theleading edge of the incident pulse is seton the vertical centerline.

k. Change the MULTIPLIER control toX1. The leading edge of the incidentpulse must be within 1 division of thevertical centerline. (If not, check the X1Position calibration, para. 5-5k (5). If stillincorrect, forward TDR to depot for repair.

l. Attach the 3 foot precision cable(Tektronix Part No. 012-0482-00) to theCABLE connector and change the FEET/DIV control to 5. Adjust the ZERO REFSET control to locate the incident pulse onthe graticule reference line (as indicatedby the arrow on the graticlde line). Thereflected pulse should be 6.3 divisions tothe right of the incident pulse.

m. Adjust the DISTANCE dial until thereflected pulse is located on the graticulereference line. The DISTANCE dial shouldread 031.5 ± 1 digit.

NOTE

When using the more sensitive ran-ges of the FEET/DIV control, the0.3 foot between the CABLE connec-tor and the sampler must be takeninto consideration.

n. Push the ZERO REF CHECK button;the incident pulse should return to thegraticule reference line. If the incident

5-2

TM 9-6625-2801-14&P

pulse does not return to the graticule re-ference line, adjust the ZERO REF SETcontrol so that the incident pulse is locatedon the graticule reference line. Releasethe ZERO REF CHECK control and checkthat the reflected pulse is located on thegraticule reference line. Adjust the DIS-TANCE dial if necessary; it must remain031.5±1 digit. (If incorrect, forward TDRto depot for repair). Return the DISTANCEdial to 000 when this step is completed.

NOTE

To more accurately check the DIS-TANCE dial, a known length of solidpolyethylene (Vp=0.66) cable (1000 to1600 feet) should be used.

o. Change the FEET/DIV control to 20,the MULTIPLIER control to X1, and the /DIV control to 200. Adjust the ZEROREF SET control so that the reflectedpulse is located exactly on the eighth gra-ticule line from the left-hand edge of thegraticule.

p. Adjust the DISTANCE dial to locatethe reflected pulse on each graticule line.The DISTANCE dial should read as follows(if incorrect, forward TDR to depot forrepair):

Graticule Line

876543210

Distance Dial Reading

000020±1 digit040±1060±1.2080±1.6100±2120±2.4140±2.8160±3.2

q. Return the DISTANCE dial to 000,change the MULTIPLIER control to X1 andrepeat the above step.

r. Push the SOLID PTFE button (donot readjust the ZERO REF SET control)and adjust the DISTANCE dial so that thereflected pulse is located on the 0 grati-cule line (first vertical line at left edge

of graticule). The DISTANCE dial shouldread between 167 and 173. Push in theOTHER button (VAR control must be fullyCw) and locate the reflected pulse on the0 graticule line with the DISTANCE dial.The DISTANCE dial should read between240 and 250. (If incorrect, forward TDRto depot for repair). Return the DIS-TANCE dial to 000 when this step is com-pleted.

s. Change the FEET/DIV control to 1,the MULTIPLIER control to X1, disconnectthe 3 foot cable from the CABLE connector,and connect the precision 50 terminatorto the CABLE connector. Adjust the ZEROREF SET control to locate the pulse on thegraticule center. Adjust the POSITIONcontrol to center the pulse on the graticule.

t. Check that the jitter is not greaterthan 0.1 division (200 ps) (see figure 5-2),

Figure 5-2. Jitter check

u. Change the MULTIPLIER control toX1 and adjust the ZERO REF SET controlto locate the pulse on the graticule center.Check that the jitter is not greater than0.2 division (40 ps). If not, forward TDRto depot for repair.

v. Change the /DIV control to 50,and turn the POSITION control counter-clockwise to display the top of the traceon the graticule, then adjust the ZERO

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TM 9-6625-2801-14&P

REF SET control to locate the pulse onthe reference graticule line.

w. Set the DISTANCE control to 500and adjust the POSITION controls to cen–ter the trace on the graticule, then returnthe DISTANCE dial to 000.

x. While viewing the trace, adjust theDISTANCE dial from 000 to 100. Thetrace must remain within ±1 division of thecenterline (±5% peak for the first 10 feet ofrise) (see figure 5-3).

Figure 5-3. Position check

y. Change the /DIV control to 5,set the DISTANCE dial to 500, re–centerthe trace, then return the DISTANCEdial to 100.

z. While viewing the trace, adjust theDISTANCE dial from 100 to 999. Thetrace must remain within ±1 division ofthe centerline (0. 5% peak beyond 10 feet).

aa. Return the DISTANCE dial to 100and push the NOISE FILTER button. Whileviewing the trace, adjust the DISTANCEdial from 100 to 999. The trace must re-main within ±0.4 division of the centerline(0.2% peak beyond 10 feet with noise filter).If there is a problem with aberrations ornoise, forward TDR to depot for repair.

ab. Release the NOISE FILTER button,return the DISTANCE dial to 000, and setthe /DIV control to 200.

ac. Adjust the POSITION control so theentire incident pulse is displayed on thecrt and check that the rise time is lessthan 0.55 division (100ps or 0.055 foot).See figure 5-4 for definition of rise time.

ad. Remove the 50 terminator fromthe CABLE connector and connect ashorted terminator to the CABLE

Figure 5-4. Rise time and fall time

5-4

TM 9-6625-2801-14&P

connector. Adjust the POSITION controlsso the entire reflected pulse is on the crt.Check that the fall time is less than 0.7division. Remove the shorted terminatorfrom the CABLE connector.

ae. Push the RECORD/CAMERA switchto CAMERA and see that fogging oscilla-tions fill the entire crt during retrace.(If fogging does not occur, return to de-pot.)

5-4. Detailed Performance Checks.

a. Introduction. This paragraph givesthe detailed procedure recommended forverifying that a TDR performs accordingto specifications. The X-Y OUTPUT MO-DULE will be covered in this procedure.

b. Equipment Required. Digital multi-meter, Fluke Model 8000A or equivalent.This will be referred to as DM 8000A orDM.

c. Preliminary Connections and Set-Up.

(1) Remove the battery pack from therear of the TDR case. Remove the frontcover of the TDR.

(2) Loosen the four screws at therear of the case and set the unit face up,Push down on the handle to break theseal; then place it face down on a flatsurface. Take hold of the sides of thecase and pull free.

(3) Remove the EMI shields from thetop and bottom of the unit. Place thebattery pack in the rear of the TDR,taking care that the polarity is correct.Connect the ac power cord to the acoutlet, at the rear of the unit, and to a115 Vac (230 Vac for Option 6) powersource.

(4) Pull the POWER switch to turnthe unit on and allow 20 minutes warm-upbefore proceeding with checks.

(5) Preset the front panel controlsas follows:

INTENSITYZERO REF SETPOSITION /DIVNOISE FILTERGAINDISTANCE DialFEET/DIVMULTIPLIERF O C U SCABLE DIELECTRICSOLID POLYSOLID PTFEOtherV A R

Fully cwFully cwMidrange500OutFully cw000200 (FIND)X1Adjust for aclear traceInOutOutFully cw

(6) Set the DM 8000A RANGE/FUNC-TION control of the digital multimeter to200 DC VOLTS. Connect the test leads tothe V- common INPUT terminals.

d. Power Supply Checks. Power supplychecks are not to be considered perform-ance checks. The location of the testpoints are shown in figure 5-5. See tableD-1 for location of board. Measure thesupply voltages with the digital multimeter(Fluke 8000A).

e. Voltage Measurements.

(1)terminalthe TDR

(2)terminal

(3)

Connect the lead from the commonto TP 6332 (black test point) onpower supply board.

Connect the lead from the V- to TP 6256 (red test point).

Adjust R6358 (HV ADJ) so thevoltmeter reads +25 V (±0.25) V.

(4) Move the test lead from TP6256to TP6411 (violet test point).

(5) Change the RANGE/FUNCTIONswitch to 20 Vdc.

(6) Adjust R6514 (+10 ADJ) so thevoltmeter reads +10 V, ±0.1V.

(7) Move the test lead from TP6411to TP6227 (green test point) and checkthat the voltmeter reads +5 V ±0.25V.

5-5

TM 9-6625-2801-14&P

Figure 5-5. Power supply board test points and adjustments

(8) Move the test lead from TP6227 toTP6218 (orange test point) and checkthat the voltmeter reads -5 V ±0.25 V.

(9) Change the RANGE/FUNCTIONswitch to 200 Vdc.

(10) Move the test lead from TP6218to connector P66 pin 6 (see figure 5-5)and check that the voltmeter reads +100V;tolerance +20 V, -5V.

(11) Move the test lead from P66 pin6 to P66 pin 7 and check that the voltmeterreads +165 V; tolerance +25 V, –5V.

f. CRT Check.

(1) Attach the precision cable to theCABLE output.

(2) Check for a step pulse on the crt.

g. Trance Focus and Astigmatism.

(1) Set the FEET/DIV to 2 with theMULTIPLIER control to X1.

(2) Locate the trace with the ZEROREF SET at the center of the graticule.

(3) Set the front panel FOCUS con-trol for the clearest possible trace.

(4) Remove the precision cable.

h. Trace Rotation.

(1) Set the /DIV

(2) Turn the ZEROclockwise and adjust the

control to 200.

REF SET fullyPOSITION con-

trols so that the trace is located on thehorizontal centerline.

5-6

the

TM 9-6625-2801-14&P

(3) Check that the trace aligns with (5) Recheck the trace rotation andhorizontal centerline. focus.

i. Trace Geometry.

(1) Move the trace with the POSITIONcontrols so that it is located 3 divisionsbelow the horizontal centerline.

(2) Check that the trace aligns withthe graticule line (has no bow).

(3) Move the trace with the POSITIONcontrols so that it is located 3 divisionsabove the horizontal centerline.

(4) Check that the trace aligns withthe graticule line (has no bow).

j. Vertical Checks.

(1) Pulse Strobe and Rise Time.

(a) Set the /DIV control to500.

(b) Use the ZERO REF SET andPOSITION controls to locate the pulseat the graticule center.

(c) Check that the incident andreflected pulse both have equal ampli-tudes (see figure 5-6 for the correctdisplay).

Figure 5-6. Pulse display AR918079

(2) Loop Gain.

(a) Set the FEET/DIV to 200, MUL-TIPLIER to X1, and /DIV to 200.

(b) Connect the precision 500terminator (Tektronix Part No. 011-0123-00) to the CABLE connector.

(c) Use the ZERO REF SET control tolocate the pulse on the graticule. Use thePOSITION controls as necessary to locate

the entire pulse step on the graticule.

(d) Adjust the front-panel GAINscrew driver control for a pulse amplitudeof 5 divisions. (Adjust the POSITIONcontrols as necessary.)

(e) Check that the rise of the pulseoccurs within 0.1 division horizontallyand there is no spike at the top of thepulse. Figure 5-7 illustrates correct andincorrect displays.

5-7

TM 9-6625-2801-14&P

Figure 5-7. Loop gain adjustments

(3) Noise.

(a) Set the /DIV to 5 and adjustthe POSITION controls so the top of thetrace is located on the horizontal center-line.

(b) Check that the peak-to-peaknoise is not greater than 5 (1 division).

(c) Push the NOISE FILTER buttonin and check that the peak–to–peak noiseis less than 2 (0.4 division).

(d) Change the FEET/DIV controlto 20.

(e) Use the POSITION controls toset the bottom of the noise pulse at thehorizontal centerline.

(f) Check that the peak-to-peaknoise is less than 2

(g) Release the NOISE FILTER but-ton and check that the peak-to-peak noiseis less than 5

(4) DC Balance.

(a) Set the /DIV to 100.

(b) Use the POSITION controls tolocate the base of the pulse at the hori-zontal centerline.

(c) Remove the 50 terminator andcheck that the trace shift is less than 1/2division. Replace 50 terminator.

(5) Vertical Attenuation.

(a) Remove the 50 terminator, setthe /DIV to 500, and turn the DIS-TANCE dial completely clockwise.

(b) Set the DM RANGE/FUNCTIONswitch to 2 on the DC VOLTS scale.

(c) Connect the lead from the DMcommon terminal to theof C2137 (on the VERTboard, figures 5-8 and

grounded terminalAMP/SLOW RAMP5-9).

5-8

TM 9-6625-2801-14&P

Figure 5-8. PC board location

Figure 5-9. Vertical amplifier/slow ramp board

(d) Connect the lead from the V- terminal to the left end of R2229. Seefigure 5-9 for the proper connectionpoints.

(e) Set the TDR POSITION controlsso that the DM reads 1.000 ±0.008 volt.

(f) Move the test lead from R2229to R2326 (see figure 5-9). The DMshould read 0.400 ±0.008 volt.

(g) Move the test lead from R2326to R2325 (see figure 5-9). The DMshould read 0.199 ±0.004 volt.

(h) Move the test lead from R2325to R2323 (see figure 5-9). The DMshould read 0.991 ±0.002 volt.

(i) Move the test lead from R2323to R2322 (see figure 5-9). The DMshould read 0.405 ±0.0008 volt.

(j) Move the test lead from R2322to R2321 (see figure 5-9). The DMshould read 0.200 ±0.0004 volt.

5-9

TM 9-6625-2801-14&P

(k) Move the test lead from R2321to R2223 (see figure 5-9). The DMshould read 0.0100 ±0.0002 volt.

(l) Remove the test leads from theTDR and turn the DISTANCE dial fullycounterclockwise.

k. Horizontal Checks.

(1) DISTANCE dial.

(a) Set controls as

/DIV 500FEET/DIV 1MULTIPLIER X1.

follows:

Attach the precision cable to the CABLEoutput.

(b) Set the front panel DISTANCEdial to exactly 031.5. Check that the leadingedge of the reflected pulse is located on thegraticule reference line within 0.1 division.

(c) Push the ZERO REF CHECKbutton; the incident pulse should returnto the graticule reference line. If thischeck fails, adjust the ZERO REF SETbutton, while holding the ZERO REFCHECK button in, so the incident pulseis located on the graticule reference line.

(2) X1 MULTIPLIER Control.

(a) Set the DISTANCE dial to 000and FEET/DIV to 5.

(b) Use the ZERO REF SET controlto locate the leading edge of the incidentpulse on the graticule reference line.

(c) Check that the leading edge ofthe reflected pulse is 6.3 divisions ±0.1division away from the incident pulse.

(3) X1 Positioning.

(a) Set the FEET/DIV to 1 with theMULTIPLIER control X1.

(b) Remove the 3-foot cable fromthe TDR.

(c) Adjust the ZERO REF SET controlso that the leading edge of the incidentpulse is set on the vertical centerline.

(d) Check that the leading edge ofthe incident pulse is located within 1 divi-sion of the vertical centerline when theMULTIPLIER control is changed to X1.

l. Fogging Circuit Adjustments.

(1) Push the CAMERA/RECORDswitch to CAMERA and see that bright(fogging) oscillations appear across theentire crt screen during retrace.

(2) Adjust the R3237 (FOG) located onthe OUTPUT AMPS board, (figures 5-8 and5-10) while holding the CAMERA/RECORDswitch to CAMERA, until fogging verticallycovers the entire crt screen during retrace.

Figure 5-10. Output amplifier board fog adjustment

5-10

m. X-Y Output Module Checks.

(1) Pen Lift Signal.

(a) Set the Digital MultimeterRANGE/FUNCTION control to 20 on theDC VOLTS scale.

(b) Turn the TDR upright.

(c) Place the terminal connectionlink of the OUTPUT MODULE board on thenegative slope terminals (see figure 2-5).

(d) Connect the lead from the DMV- terminal to the X-Y OUTPUT MODULEPEN LIFT red terminal and the lead fromthe DM common terminal to the X-Y OUT-PUT MODULE PEN LIFT black terminal.

(e) Check that the DM showsapproximately +5 volts.

(f) Momentarily push the RECORD/CAMERA switch to RECORD, then releasethe switch. Check that the voltage goesto +0.5 volt or less and returns to approx-imately +5 volts at the end of the sweep.

(g) Move the terminal connectionlink to the positive slope terminals on theX-Y OUTPUT MODULE board.

(h) Check that the DM reads ap-proximately -0.5 volt.

TM 9-6625-2801-14&P

(i) Push the RECORD/CAMERAswitch to RECORD and check that the DMreads +4 volt or greater, then returns toapproximately 0.5 volt at the end of thesweep.

(2) Y Output.

(a) Move the test leads from thePEN LIFT terminals to the correspondingY terminals of the X-Y OUTPUT MODULE.

(b) Set the TDR ZERO REF SETcompletely clockwise.

(c) Push the RECORD/CAMERAswitch to RECORD and adjust the TDRPOSITION controls so that the DM reads0.0 volt.

(d) Turn the TDR ZERO REF SETcompletely counterclockwise and checkthat the DM reads approximately +0.04volt . Release the RECORD switch.

(e) Move the test leads to the Xterminals.

(f) Momentarily press the RECORD/CAMERA switch to RECORD, then re–lease.

(g) Check that the voltage readsfrom 0 to 1 V (100 mV/div) as the dotmoves across the screen.

Section III. FAULT ISOLATION

5-5. Introduction. Trouble shooting will are referenced in the troubleshootingbe confined to power failure. A power tables as required. Replacement partsfailure indication would be no display on are listed in Appendix C. Proceduresthe crt or no indication on the battery for parts replacement are given in Chap-meter. If the required corrective action ter 6. Perform procedures given indoes not restore power, forward TDR to paragraph 5-2 and perform troubleshootingdepot for repair. Parts location drawings given in table 5-1.

Table 5-1. TDR Troubleshooting Procedure

Para.ref. Symptom Corrective Action

7-4b No CRT display Check fuses2-3a No battery indication Charge battery

Battery does not charge Replace battery

5-11/(5-12 blank)

TM 9-6625-2801-14&P

CHAPTER 6

MAINTENANCE INSTRUCTIONS

Section I. GENERAL

6-1. General. The TDR is maintained by (a) inspect; (b) test; (c) service;direct support maintenance level person- (d) install; (e) replace the equipment.nel. The maintenance functions of the DS Calibration of the TDR is performed bylevel personnel are shown in the Mainten- a separate calibration/repair facility inante Allocation Chart (MAC) in Appendix accordance with TB 11-6625-2860-35 forB. The maintenance functions are to: the TDR.

Section II. MAINTENANCE INSTRUCTIONS

6-2. Maintenance Efforts. Table 6-1 a. Battery pack replacement. Seelists the various maintenance efforts re- figure C-1 for location. Loosen the twoquired, the frequency of performance, thumbscrews and pull out the batteryand references to the actual procedures pack. Insert new battery pack andto be performed. secure the two thumbscrews.

Table 6-1. Maintenance Efforts

Maintenance effort

Installation, replacement

Inspect and services:

Preventive mainte-

nance

Battery maintenance

Preparation for ship-

ment and storage

Tests

Repair

Frequency of performance

On receipt of equipment

As required

Every 30 days

As required

Every 30 days or

after repair and

service

As required

Reference

Para 3-1

Paras 3-6, 3-7

Para 3-7

Chapter 9

Para 5-3, 5-4

Chapter 7

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TM 9-6625-2801-14&P

CHAPTER 7

REPAIR INSTRUCTIONS

Section I.

7-1. Responsibilities. Repair at the di-rect support (DS) level consists of re-placing damaged or malfunctioning compo-nents found during inspection andcheckout. Removal of major assembliesis performed only to the extent necessaryto accomplish the required repairs. Re-fer to the Maintenance Allocation Chart(MAC) in appendix Blevel of responsibility

to determine thefor maintenance

GENERAL

functions. Items not identified in theMAC, such as accessory equipment, maybe repaired by direct support mainte-nance personnel, if authorized by perti-nent directives.

7-2. Depot Repaired Components. Itemsthat cannot be repaired or disposed ofat DS should be sent to depot for repairor disposition. Refer to the MAC.

Section II. REPAIR OF TDR

7-3. General. This section contains in-structions for removal and replacementof assemblies and parts that need repair.Refer to appendix C for location of parts.

7-4. Repair and Replacement Instructions.

a. Fuses. All ac line fuses are locatedon the front panel. All dc fuses andspares are located on the power supplyboard inside the instrument. Removethe TDR from its case (See paragraph5-4c). Remove the aluminum shield fromthe top of the unit. The fuses are up-right plug-in types located near thecenter of the instrument (see figures7-1 and C-1).

When the cabinet is removed highvoltages may be present.

b. Replacing Case. To replace theease on the TDR proceed as follows:

(1) Remove any termination andadapters from the cable connector.

Figure 7-1. Power supply board DC fuselocation

(2) Remove the battery pack andpower cord from the back of the TDR.

7-1

TM 9-6625-2801-14&P

(3) Place the EMI shields on the topand bottom of the TDR.

(4) Stand the TDR on its face.

(5) Slide the case over the back ofthe unit, until it has reached the sub-panel.

(6) Tighten the four screws on theback of the case until the case is alignedwith the groove at the back of the sub–panel.

(7) Make sure the case is in thegroove; then, using a torque screw-driver, tighten the four screws to 10inch–pounds.

NOTE

If the screws are not tightenedequally to the required torque,the watertight integrity of thecase can be destroyed.

(8) Place the battery pack in itscompartment and tighten the two screws(finger tight is sufficient).

(9) Place the power cord and therest of the accessories in the front coverstorage compartment and latch it closed.

(10) Place the front cover over thefront cover panel and close the latches.

7-2

TM 9-6625-2801-14&P

CHAPTER 8

FINAL INSPECTION

Section I. GENERAL

8-1. General. To ensure operational before the TDR is either returned to usecondition of the TDR after repair or re– or placed in stock. The inspection is aplacement, a final inspection must be series of checks.made. The inspection is to be made

Section II. FINAL INSPECTION CHECKS

8-2. Final Inspection Checks. Table 8-1 after it is repaired or replaced. Refer-lists final inspection checks for the TDR ences are provided for each check.

Table 8-1. TDR final inspection checks

Assembly repaired Assembly Checksor replaced reference

designation

Assembled TDR a. Inspect for visible damage.(main case) and b. Check for completeness.all accessories. c. Perform turn-on procedures.

References

Paragraph 1-5 b.Table 1-1. Paragraph 2-3.

8-1/(8-2 blank)

TM 9-6625-2801-14&P

CHAPTER 9

PREPARATION FOR SHIPMENT AND STORAGE

Section I. PREPARATION FOR TRAVEL (IN SHELTER)

9-1. General. Preparation for travel ap-plies to the TDR when contained in theshelter. No special preparation is re-quired, but the following general stepsshould be taken:

Section II.

9-2. Preparation of TDR.

a. Packing.

(1) Place TDR in corrugated contain-ers in which it was shipped in accordancewith Federal Specification PPP-B–636,style RSC (export), type CF, grade W5c,class WR.

(2) At the corners of each container,and to block the panel assembly aboveand below, re-use built-up corrugatedblocking with double wall ac flute in ac-cordance with Federal Specification PPP–F-320, type CR, grade DW200, class DOM.

Section III.

9-3. Preparation.

a. Perform applicable checks listed intable 8-1 to ensure operational readinessof the equipment. These checks must beperformed every 90 days while equipmentis in administrative storage.

b. Select a storage area or site thatbest conforms to the following require-ments:

a. Place all accessory equipment andgroup test cables in the TDR cover.

b. Secure the cover in the closedposition with the two side clamps.

SHIPMENT

(3) Apply adhesive per MIL-A-101to flaps of containers and close the flaps.

(4) Apply 2-inch waterproof tape inaccordance with Federal SpecificationPPP-T-76 over all corners and openseams.

(5) Mark container in accordancewith MIL–STD-129.

b. Shipping Documents. Prepareshipping documents to accompany allfreight in accordance with AR 725.50

STORAGE

(2) Maximum protectionweather and pilferage.

(3) Adequate drainage.

against

(4) Access to permit inspection,maintenance, and removal from storage.

c. Place equipment on blocks or dun-nage to prevent contact with the groundor a damp floor.

(1) Level storage surface.

9-1

TM 9-6625-2801-14&P

d. Mark or tag the equipment “admin-istrative storage.” Equipment will not beoperated while in the administrative stor–age category except at the 90–day inter-vals when checkout is performed to en–sure operation condition (refer to TM740-90-1).

9-4. Inspection and Maintenance.

a. Visually inspect the equipment atleast once each month. For equipmentstored outdoors, a visual inspectionshould be made immediately followinghard rains, heavy snow storms, wind-storms, and other adverse conditions.

b. Disassemble or unpack equipmentonly as necessary to determine the fullextent of deterioration or damage foundduring visual inspection.

c. Perform preventive maintenance orrepair immediately to correct any deterior–ation or damage.

d. Record each inspection, conditionof the equipment at time of inspection,and corrective action taken. Attach thisrecord to the equipment in such a manneras to be protected from the elements.

9-2

TM 9-6625-2801-14&P

APPENDIX A

REFERENCES

A-1. Administrative Aids

Index of Administrative Publications . . . . . . . . . . . . . . . DA Pam 310-1The Army Maintenance Management System . . . . . . . . . . . . . TM 38-750

A-2. Related Maintenance Technical Manuals

Materials Used for Cleaning, Preserving, Abrading and Cementing OrdnanceMateriel and Related Materials Including Chemicals . . ..TM 9-247

Painting Instructions for Field Use . . . . . . . . . . . . . . . . TM 43-0139

A-3. Related Commercial Maintenance Manuals

Tektronix 1502-1 Time Domain Reflectometer, Instruction Manual-070-1792-00, September 1975

A-4. Related Calibration Manuals

Calibration Requirements for the Maintenance of ArmyMateriel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TB 43-180

Calibration Procedure for Time Domain ReflectometerTektronix Type 1502-l...... . . . . . . . . . . . . . . . . . . . TB 11-6625-2860-35

A-5. Other Related Publications

Requisitioning, Receipt, and Issue System . . . . . . . . . .

Administrative Storage . . . . . . . . . . . . . . . . . . . . . . . . . .Destruction to Prevent Enemy Use . . . . . . . . . . . . . . . . .Marking for Shipment and Storage . . . . . . . . . . . . . . . . .Tape, Pressure-Sensitive Adhesive Paper (for carton

sealing) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Tape, Pressure-Sensitive Adhesive, Masking, Paper. . .Adhesive, Water Resistant . . . . . . . . . . . . . . . . . . . . . . .

Fiberboard; Corrugated and Solid, Sheet Stock(Container Grade), and Cut Shapes

Plastic Film (Polyethylene Thin Gage) . . . . . . . . . . . . . .Box, Fiberboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

AR 725-50TM 740-90-1TM 750-244-2MIL-STD-129

PPP-T-76UU-T-106MMM-A-260(Replaces MIL-A-101)

L-P-378PPP-B-636

A-1/(A-2 blank)

TM 9-6625-2801-14&P

B-1. General.

APPENDIX B

MAINTENANCE ALLOCATION CHART

Section I. INTRODUCTION

a. The maintenance allocation chartidentifies the maintenance operations thatmust be performed. It assigns each ofthose operations to the lowest level ofmaintenance authorized to perform thecomplete task, or any part of the task,in terms of availability of time, tools,test and support equipment, skills andemployment of the subsystem.

b. The Maintenance Allocation Chart(MAC) in section II designates overallresponsibility for the performance ofmaintenance functions for the TDR.

c. Section III lists the special toolsand test equipment required for eachmaintenance function as referenced fromsection II.

d. Section IV contains supplementalinstructions on explanatory notes for aparticular maintenance function.

B-2. Maintenance Functions.

a. Inspect. To determine the service-ability of an item by comparing its phys-ical, mechanical and/or electrical charac-teristics with established standardsthrough examination.

b. Test. To verify serviceability anddetect incipient failure by measuring themechanical or electrical characteristics ofan item and comparing those characteris-tics with prescribed standards.

c. Service. Operations requiredperiodically to keep an item in proper op-crating condition i.e., to clean (decon-taminate), preserve, drain, paint or

replenish fuel, lubricants, hydraulicfluids, or compressed air supplied.

d. Adjust. To maintain, within pre-scribed limits, by bringing into properor exact position, or by setting the opera-ting characteristics to specified para-meters.

e. Align. To adjust specified variableelements of an item to bring about opti-mum or desired performance.

f. Calibrate. To determine and causecorrections to be made or to be adjustedon instruments or test measuring anddiagnostic equipments used in precisionmeasurement. Consists of comparisons oftwo instruments, one of which is a certi-fied standard of known accuracy, to de-tect and adjust any discrepancy in the ac-curacy of the instrument being compared.

g. Install. The act of emplacing, seat-ing or fixing into position an item, part,or module (component or assembly) in amanner to allow the proper functioning ofan equipment or system.

h. Replace. The act of substituting aserviceable like type part, subassembly,or module (component or assembly) for anunserviceable counterpart.

i. Repair. The application of mainte-nance services1 or other maintenance ac-tions 2 to restore serviceability to an item

1Services - inspect, test, service, adjust,align, calibrate, or replace.

2Action – welding, grinding, riveting,straightening, facing, remachining, orresurfacing.

B-1

TM 9-6625-2801-14&P

by correcting specific damage, fault, mal-function, or failure in a part, subassem-bly, module (component or assembly),and item, or system.

j. Overhaul. The maintenance effort(services/actions) necessary to restorean item to a completely serviceable/opera-tional condition as prescribed by mainte-nance standards (i.e., DMWR) in appro-priate technical publication. Overhaul isnormally the highest degree of mainte-nance performed by the Army. Overhauldoes not normally return an item to likenew condition.

k. Rebuild. Consists of those ser-vices/actions necessary for the restorationof unserviceable equipment to a like newconditions in accordance with originalmanufacturing standards. Rebuild is thehighest degree of materiel maintenanceapplied to Army equipment. The rebuildoperation includes the act of returningto zero those age measurements (hours/miles, etc.) considered in classifyingArmy equipments/components.

B-3. Column Entries Used in the MAC.

a. Column 1, Group Number. Column1 lists group numbers, the purpose ofwhich is to identify components, assem–blies, subassemblies, and modules withthe next higher assembly.

b. Column 2, Component/Assembly.Column 2 contains the names of compo-nents, assemblies, subassemblies, andmodules for which maintenance is author–ized.

c. Column 3, Maintenance Functions.Column 3 lists the functions to be per-formed on the item listed in column 2.(For detailed explanation of thesefunctions , see para. B-2).

d. Column 4, Maintenance Category.

(1) Column 4 specifies, by the listingof a “work time” figure in the appropriatesub-column(s), the lowest level of

maintenance authorized to perform thefunction listed in column 3. This figurerepresents the active time required toperform the maintenance function, at theindicated level of maintenance.

(2) If the number or complexity ofthe tasks within the listed maintenancefunction vary at different maintenancelevels, appropriate “work time” figureswill be shown for each level. The num-ber of man-hours specified by the “worktime” figure represents the average timerequired to restore an item (assembly,subassembly, component, module, enditem, or system) to a serviceable conditionunder typical field operating conditions.This time includes preparation time,troubleshooting time, and quality assur-ance/quality control time in addition tothe time required to perform the specifictasks identified for the maintenance func-tions authorized in the maintenance al-location chart. The symbol designationsfor the various maintenance levels are asfollows:

C - Operator or crew.O - Organization maintenance.F - Direct support maintenance.H - General support maintenance.D - Depot maintenance.

e. Column 5, Tools and Equipment.Column 5 specifies, by code, those com-mon tool sets (not individual tools) andspecial tools, test, and support equip-ment required to perform the designatedfunction.

f. Column 6, Remarks. Column 6contains a letter code in alphabet orderwhich is keyed to the remarks containedin section IV.

B-4. Column Entries Used in Tool andTest Equipment Requirements (SectionIII).

a. Column 1, Tool or Test EquipmentReference Code. The tool and test equip-ment reference code correlates with a

B-2

TM 9-6625-2801-14&P

maintenance function on the identifiedend item or component.

e. Column 5, Tool Number. The manu-facturer’s part number.

b. Column 2, Maintenance Category.The lowest level of maintenance author-

B-5. Explanation of Columns to Section IV.

ized to use the tool or test equipment.a. Reference Code. The code scheme

c. Column 3, Nomenclature. Name orrecorded in column 1, section III.

identification of the tool or test equip-b. Remarks.

ment. This column list infor-mation pertinent to the maintenance

d. Column 4, National/NATO StockNumber. The National or NATO stocknumber of tool or test equipment.

function being performed as indicated onthe MAC, section II.

Section II. MAINTENANCE ALLOCATION CHART FOR TIME DOMAINREFLECTOMETER TYPE 1502-1 (TDR)

(1)GROUP

NUMBER

1

1

(2)

COMPONENT. ASSEMBLY

Tektronix Time Domain fteflectometer Type 1502-%

fh,ttery

(3)

MAINTENANcEFUNCTION

InspectTestServicelnst.dlReplace

ServiceReplace

(4)

MAINTENANCE C4TEGORY—c o F

.1

.5

.5

.2

.2

!. o

H D

(5)

TOOLS ANDEQUIPMENT

(6)REMARKS

B-3

TM9-6625-2801-14&PSECTION III. TOOL AND TEST EQUIPMENT REQUIREMENTSFOR TEKTRONIX TIME DOMAIN REFLECTOMETER TYPE 1502-1

TOOL OR TESTEQUIPMENT MAINTENANCE NATIONAL/NATO TOOLREF NUMBER CATEGORY NOMENCLATURE STOCK NUMBER NUMBER

1 F FLUKE 8000ADIGITAL MULTIMETER

2 F SHORTED BNC CONNECTOR

B-4

TM 9-6225-2801-14&P

APPENDIX C

MAINTENANCE REPAIR PARTS LIST

C-1. Introduction. This appendix listsauthorized repair parts for performanceof maintenance of the Time Domain Re-flectometer Tektronix Type 1502-1.

C-2. Explanation of Columns. Thefollowing provides an explanation ofcolumns found in the listings.

a. Figure. This column indicates thefigure number of the illustration in whichthe item is shown.

b. Item. This column indicates thenumber used to identify each item calledout in the illustration.

c. Part No. This column indicates theprimary number used which controls thedesign and characteristics of the item bymeans of its engineering drawings, speci-fications, standards, and inspection re-quirements, to identify an item or rangeof items.

NOTE

When a stock numbered item isrequisitioned, the repair partreceived may have a differentpart number than the partbeing replaced.

d. Description. This column providesthe item name and a minimum descriptionto identify the item.

e. Manufacturer. This column pro-vides the name of the manufacturer of apart where the manufacturer differsfrom the manufacturer of the TimeDomain Reflectometer.

C–3. Abbreviations.

#Actr

" InchNumber sizeActuator

AdptrAlignAlAssemAssyAttenA W GB dBrktBrsBrzBshgCabCapCerChasCktCompConnCovCplgCrtCurDegDiaD w rElctrnElecElctltElemEPLEqptFbExtFilFlexFlhFlmFltrFrFstnrFtFxdGsktH dHdlHexHex hd

AdapterAlignmentAluminumAssembledAssemblyAttenuatorAmerican wire gageBoardBracketBrassBronzeBushingCabinetCapacitorCeramicChassisCircuitCompositionConnectorCoverCouplingCathode ray tubeCurrentDegreeDiameterDrawerElectronElectricalElectrolyticElementElectrical parts listEquipmentFast blowExternalFillister headFlexibleFlat headFilmFilterFrame or frontFastenerFootFixedGasketHeadHandleHexagonHexagonal head

C-1

TM 9-6225-2801-14&P

Hex socHlcpsHlextH vICIDIdentImplrInIncandInsulIntlLEDLphldrMachMechMetMtgNipNon wirO B DO DO v hPCP C BPh brzPlPlstcPNPnhPwrQtzRcptResRfR g d

Hexagonal socketHelical compressionHelical extensionHigh voltageIntegrated circuitInside diameterIdentificationImpellerInchIncandescentInsulatorInternalLight emitting diodeLampholderMachineMechanicalMetalMountingNippleNot wire woundOrder by descriptionOutside diameterOval headPrinted circuitPrinted circuit boardPhosphor bronzePlain or platePlasticPart numberPan headPowerQuartzReceptacleResistorRadio FrequencyRigid

RlfRtnrSchScopeScrSESectSelSemicondSensShldShldrSktSlSlflkgSlvgSprSqSSTStlS wTTermThdThkTnsnT p gTrhVVarW/WshrW WXfmrXstrXtal

ReliefRetainerSocket headOscilloscopeScrewSingle endSectionSelectedSemiconductorSensitiveShieldShoulderedSocketSlideSelf-lockingSleevingSpringSquareStainless steelSteelSwitchTubeTerminalThreadThickTensionTappingTruss headVoltageVariableWithWasherWire woundTransformerTransistorCrystal

C-2

TM9-6625-2801-14&P

TABLE C-1. REPLACEABLE ELECTRICAL PARTS

FIGURE ITEM FIGURE DESCRIPTION

C-1 1 159-0029-00 *FUSE, CARTRIDGE:0.3A,3AG, SLO-BLOWC-1 1 150-0029-00 *FUSE, CARTRIDGE:0.3A,3AG,SLO-BLOWC-1 2 159-0128-00 *FUSE, CARTRIDGE:2A,125V, 5SECC-1 2 159-0128-00 *FUSE, CARTRIDGE:2A,125V, 5SECC-1 2 159-0128-00 *FUSE, CARTRIDGE:2A,125V, 5 SECC-1 2 159-0128-00 *FUSE, CARTRIDGE:2A,125V, 5 SECC-1 3 016-0595-00 BATTERY PACK

TABLE C-2. STANDARD ACCESSORIES

FIGURE ITEM PART NO. DESCRIPTION

C-2 1 016-0297-00 VISOR, CRT:C-2 2 103-0028-00 ADAPTER, CONN:BNC TO BNCC-2 3 011-0123-00 TERM, COAXIAL:50 OHM, BNCC-2 4 012-0482-00 CABLE ASSY, RF:50 OHM, 36 INCH LONGC-2 5 161-0066-00 CABLE ASSY, PWR:3 WIRE, 98 INCH LONGC-2 6 003-0700-01 RULE, SLIDE:TIME DOMAIN REFLECTOMETERC-2 7 159-0029-00 FUSE, CARTRIDGE:0.3A,3AG,SLO-BLOW

159-0054-00 FUSE, CARTRIDGE:0.15A,3AG,250V,SLO-BLOW

C-2 8 378-0055-00 FILTER, MESH:CRT

*STOCKED ITEM

C-3

TM 9-6225-2801-14&P

Figure C-1. Replaceable electrical parts

C-4

TM 9-6225-2801-14&P

Figure C-2. Standard accessories

C-5/(C-6 blank)

TM 9-6625-2801-14&P

INDEX

Subject

Chapter, Para.Figure, Table

Number

A, B

Accessories, Control Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3cAccessories, Use. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3d

Camera Use with TDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3d(3)Mesh Filter for the CRT... . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3d(1)Viewing Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3d(2)

C

Cable Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Cable Problems, Typical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Cable Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Connection of Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Evaluating a Discontinuity . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Locating a Discontinuity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Other Than 50 Ohms Impedance . . . . . . . . . . . . . . . . . . . . . . . . .Typical Cable Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Camera Use With TDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Checkout Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Checks, Detailed Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Fogging Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Horizontal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Preliminary Connections and Set-up . . . . . . . . . . . . . . . . . . . . . .Trace Focus and Astigmatism . . . . . . . . . . . . . . . . . . . . . . . . . . .Trace Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Trace Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Vertical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Voltage Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .X-Y Output Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Circuit Analysis, Simplified . . . . . . . . . . . . . . . . . . . . . .. .....Chart Recorder ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Puller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CleaningCrt Implosion Shield . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Content Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Control Settings

Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TDR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-42-4e2-42-4a2-4c2-4b2-4e2-4d1-3, 3-92-2d(3)3-25-45-4f5-4b5-4l5- 4k5-4a5-4d5-4c5-4g5-4i5-4h5-4j5-4e5-4m4-14-1c4-1a4-1b

3- 6d3- 6C3-6a3-6b1-1b

2-3c2-3b

Index 1

TM 9-6625-2801-14&P

INDEX - Continued

Subject

Chapter, Para.Figure, Table

Number

Depot RepairedDescription . . .

AccessoriesGeneral . . .Main Case .

D,E

Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Destruction of Material to Prevent Enemy Use . . . . . . . . . . . . . . . .Detailed Performance Checks and Adjustments . . . . . . . . . . . . . . . .

Crt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Fogging Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Horizontal.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Preliminary Connections and Set-up . . . . . . . . . . . . . . . . . . . . . .Trace Focus and Astigmatism . . . . . . . . . . . . . . . . . . . . . . . . . . .Trace Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Trace Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Vertical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Voltage Measurements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .X-Y Output Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DiscontinuityEvaluation of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Location of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

F, G, H

Fault Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Final Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Final Inspection Checks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Forms and Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Front Panel Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . . .Fuses, Repair and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . .

I, J, K

Incident and Reflected Pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Inspection and Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

L

Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-21-61-6b(2), T 1-11-6a1-6b(1)1-45-45-4f5-4b5-4l

5-4k5-4a5-4d5-4C5-4g5-4i5-4h5-4j5-4e5-4m

2-4c2-4b

5-5, T 5-18-18-2, T 8-11-22-1, T 2-1,7-4a

F 2-49-4

3-4

F 2-1

Index 2

TM 9-6625-2801-14&P

INDEX - Continued

Chapter, Para.Figure, Table

Subject Number

M, N

Maintenance Allocation Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1Maintenance Efforts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2, T6-1Maintenance Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1Maintenance Repair Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1Mesh Filter Use . . . . . . . .

Operating Power SelectionBattery Connections . .230 Volt Operation . . .

Performance Checks . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3d(1)

O

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2a, F 2-2

. . . . . . . . . . . . . . . . . . . . . . . . ........ 2-2b, F 2-3

P, Q

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

Performance Checks/Fault Isolation . . . . . . . . . . . . . . . . . . . . . . . .Preparation for Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Packing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Shipping Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Preparation for Performance Checks . . . . . . . . . . . . . . . . . . . . . . . .Preparation for Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Preparation for Travel (In Shelter) . . . . . . . . . . . . . . . . . . . . . . . . .Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

R

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Repair and Replacement Instructions . . . . . . . . . . . . . . . . . . . . . . .

Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Repair Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Repair Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Replaceable Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

S

Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ......Servicing Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Shipment, Preparation for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Packing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Shipping Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Simplified Circuit Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Chart Recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Pulser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...Sampling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Storage, Preparation for . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-19-29-2a9-2b5-29-39-13-51-1a

App. A7-47-4b7-4a7-13-3C-1

1-13-79-29-2a9-2b4-14-1c4-1a4-1b9-3

Index 3

TM 9-6625-2801-14&P

INDEX - Continued

Subject

T

Tabulated Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TDR Control Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Travel (In Shelter), Preparation for . . . . . . . . . . . . . . . . . . . . . . . .Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Turn-on Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

U

Unpacking and Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

V

Viewing Hood Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

W, X, Y, Z

Watertight Seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter, Para.Figure, Table

Number

1-7, T2-3b9-1T 5-12-3

1-2

3-1

2-3d(22)

3-8

Index 4

TM 9-6625-2801-14&P

By Order of the Secretary of the Army:

Official:

ROBERT M. JOYCEBrigadier General, United States Army

The Adjutant General

Distribution:

To be distributed in accordance with Special List.

E. C. MEYERGeneral, United States Army

Chief of Staff

TM 9-6625-2801-14&P