BIRD TENULINE 8321 User manual

8320 SERIES
TENULINE®ATTENUATOR
Operation Manual
©Copyright 2017 by Bird Technologies, Inc
Instruction Book Part Number 920-8320S Rev. B
Tenuline ® is a registered trademark
of Bird Electronic Corporation

i
Safety Precautions
Thefollowingaregeneralsafetyprecautionsthatarenotnecessarilyrelatedto
anyspecificpartorprocedure,anddonotnecessarilyappearelsewhereinthis
publication.Theseprecautionsmustbethoroughlyunderstoodandapplytoall
phasesofoperationandmaintenance.
WARNING
KeepAwayFromLiveCircuits
OperatingPersonnelmustatalltimesobservegeneralsafetyprecautions.Do
notreplacecomponentsormakeadjustmentstotheinsideofthetest
equipmentwiththehighvoltagesupplyturnedon.Toavoidcasualties,always
removepower.
WARNING
ShockHazard
DonotattempttoremovetheRFtransmissionlinewhileRFpowerispresent.
WARNING
DoNotServiceOrAdjustAlone
Undernocircumstancesshouldanypersonreachintoanenclosureforthe
purposeofserviceoradjustmentofequipmentexceptinthepresenceof
someonewhoiscapableofrenderingaid.
WARNING
SafetyEarthGround
Anuninterruptibleearthsafetygroundmustbesuppliedfromthemain
powersourcetotestinstruments.Groundingoneconductorofatwo
conductorpowercableisnotsufficientprotection.Seriousinjuryordeathcan
occurifthisgroundingisnotproperlysupplied.
WARNING
Resuscitation
Personnelworkingwithornearhighvoltagesshouldbefamiliarwithmodern
methodsofresuscitation.
WARNING
RemovePower
Observegeneralsafetyprecautions.Donotopentheinstrumentwiththe
powerapplied.

SafetyPrecautions
ii
Safety Symbols
Note: Callsattentiontosupplementalinformation.
WARNING
Warningnotescallattentiontoaprocedure,whichifnotcorrectlyperformed,
couldresultinpersonalinjury.
CAUTION
Cautionnotescallattentiontoaprocedure,whichifnotcorrectlyperformed,
couldresultindamagetotheinstrument.
Thecautionsymbolappearsontheequipmentindicatingthereis
importantinformationintheinstructionmanualregardingthat
particulararea

8320SeriesTenuline®Attenuator
iii
Warning Statements
Thefollowingsafetywarningsappearinthetextwherethereisdangerto
operatingandmaintenancepersonnel,andarerepeatedhereforemphasis.
Seepages 6 and 8 .
Seepages 7 , 9 ,and 10 .
Seepage 8 .
WARNING
Theventplugmustbeinstalledatalltimeswhentheunitisinoperationor
cooling.Alwayschecktoensureventplugisinstalledpriortooperation.
Failuretodothiscouldresultindamagetotheequipmentandendangerthe
operator’ssafety.
WARNING
LeakingRFenergyisapotentialhealthhazard.
Neverattempttoconnectordisconnectequipmentfromthetransmission
linewhileRFpowerisbeingapplied.
Severeburns,electricalshock,ordeathcanoccur.
WARNING
Usingtheattenuatorintheupperendofitspowerdissipationrangewillcause
thehousingtobecomehot!
Careshouldbeexercisedintouchingthem.

SafetyPrecautions
iv
Caution Statements
Thefollowingequipmentcautionsappearinthetextwhenevertheequipmentis
indangerofdamage,andarerepeatedhereforemphasis.
CAUTION
Seepage
5 .
Seepages 7 and 8 .
Seepage 15 .
Seepage 16 .
Seepage 19 .
TheAttenuatorisdesignedtobeoperatedinthehorizontalposition,with
mountingbracketsdown.
Operationinanyotherorientationwillcauseinsufficientcoolingoftheunit
leadingtoprematurefailure.
CAUTION
Theinputandoutputendsoftheseattenuatorsareclearlylabeled.Donot
coupleanattenuatorbackwardstothedirectionofpowerflow.Destructionof
theoutputresistorwillresult.
CAUTION
AvoidputtingdirectpressureontheInputconnector.Theinputconnector
maybeinadvertentlydamagedcausinginaccurateoperationorpremature
failure.
CAUTION
Usecarewhenremovingorinstallingendcovertoavoiddamagingendcover
sealortheo‐ringsealontheRFoutputsection.
CAUTION
Donotoverfillthecoolanttankwithcoolant.Roommustbeallowedfor
expansionoftheheatedcoolant.

8320SeriesTenuline®Attenuator
v
Safety Statements
USAGE
ANY USE OF THIS INSTRUMENT IN A MANNER NOT SPECIFIED BY
THE MANUFACTURER MAY IMPAIR THE INSTRUMENT’S SAFETY
PROTECTION.
USO
EL USO DE ESTE INSTRUMENTO DE MANERA NO ESPECIFICADA
POR EL FABRICANTE, PUEDE ANULAR LA PROTECCIÓN DE
SEGURIDAD DEL INSTRUMENTO.
BENUTZUNG
WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM
HERSTELLER BESCHRIEBEN, KANN DIE GERÄTESICHERHEIT
BEEINTRÄCHTIGT WERDEN.
UTILISATION
TOUTE UTILISATION DE CET INSTRUMENT QUI N’EST PAS
EXPLICITEMENT PRÉVUE PAR LE FABRICANT PEUT
ENDOMMAGER LE DISPOSITIF DE PROTECTION DE
L’INSTRUMENT.
IMPIEGO
QUALORA QUESTO STRUMENTO VENISSE UTILIZZATO IN MODO
DIVERSO DA COME SPECIFICATO DAL PRODUTTORE LA
PROZIONE DI SICUREZZA POTREBBE VENIRNE COMPROMESSA.

SafetyPrecautions
vi
SERVICE
SERVICING INSTRUCTIONS ARE FOR USE BY SERVICE - TRAINED
PERSONNEL ONLY. TO AVOID DANGEROUS ELECTRIC SHOCK, DO
NOT PERFORM ANY SERVICING UNLESS QUALIFIED TO DO SO.
SERVICIO
LAS INSTRUCCIONES DE SERVICIO SON PARA USO EXCLUSIVO
DEL PERSONAL DE SERVICIO CAPACITADO. PARA EVITAR EL
PELIGRO DE DESCARGAS ELÉCTRICAS, NO REALICE NINGÚN
SERVICIO A MENOS QUE ESTÉ CAPACITADO PARA HACERIO.
WARTUNG
ANWEISUNGEN FÜR DIE WARTUNG DES GERÄTES GELTEN NUR
FÜR GESCHULTES FACHPERSONAL. ZUR VERMEIDUNG
GEFÄHRLICHE, ELEKTRISCHE SCHOCKS, SIND
WARTUNGSARBEITEN AUSSCHLIEßLICH VON QUALIFIZIERTEM
SERVICEPERSONAL DURCHZUFÜHREN.
ENTRENTIEN
L’EMPLOI DES INSTRUCTIONS D’ENTRETIEN DOIT ÊTRE RÉSERVÉ
AU PERSONNEL FORMÉ AUX OPÉRATIONS D’ENTRETIEN. POUR
PRÉVENIR UN CHOC ÉLECTRIQUE DANGEREUX, NE PAS
EFFECTUER D’ENTRETIEN SI L’ON N’A PAS ÉTÉ QUALIFIÉ POUR CE
FAIRE.
ASSISTENZA TECNICA
LE ISTRUZIONI RELATIVE ALL’ASSISTENZA SONO PREVISTE
ESCLUSIVAMENTE PER IL PERSONALE OPPORTUNAMENTE
ADDESTRATO. PER EVITARE PERICOLOSE SCOSSE ELETTRICHE
NON EFFETTUARRE ALCUNA RIPARAZIONE A MENO CHE
QUALIFICATI A FARLA.

8320SeriesTenuline®Attenuator
vii
About This Manual
Thismanualcoverstheoperatingandmaintenanceinstructionsforthe
followingmodels:
Changes to this Manual
Wehavemadeeveryefforttoensurethismanualisaccurate.Ifyoudiscoverany
errors,orifyouhavesuggestionsforimprovingthismanual,pleasesendyour
commentstoourSolon,Ohiofactory.Thismanualmaybeperiodicallyupdated.
Wheninquiringaboutupdatestothismanualrefertothepartnumberand
revisiononthetitlepage.
Chapter Layout
Introduction — Providesgeneralinformationaboutthe8320series
attenuators.
Theory of Operation — Describesindetailtheconstructionofthe8320
seriesattenuatorsandhowcoolingisachieved.
Installation — Providesinstructionsonhowtosetupthe8320series
attenuatorsforworryfreeoperation.
Operating Instructions — Detailsthestepsrequiredtosafelyoperatethe
8320seriesattenuators.
Maintenance — Providesroutinemaintenanceinspectionsandprocedures,
detailedtroubleshootingshouldmalfunctionsoccur,andstepbysteprepair
procedures.
Specifications — Givesdetailedspecificationsforeach8320seriesmodel,as
wellasacomprehensivelistofavailablereplacementpartsandoptionalRF
connectors.
8321 8322 8323 8325

viii
Table of Contents
Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i
SafetySymbols..................................................ii
WarningStatements.............................................iii
CautionStatements..............................................iv
SafetyStatements...............................................v
About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
ChangestothisManual..........................................vii
ChapterLayout................................................vii
Chapter 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
GeneralDescription..............................................1
OperatingEnvironment.......................................1
RFConnectors...............................................2
Chapter 2 Theory of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
AttenuatorConstruction..........................................3
Cooling........................................................3
CoolantExpansion............................................4
HeatDissipation..............................................4
Chapter 3 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
UnpackingandInspection.........................................5
Location.......................................................5
Mounting......................................................6
Setup..........................................................6
VentPlugInstallation(Model8325).............................6
Installingina50OhmLine.....................................7
Chapter 4 Operating Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
NormalOperation...............................................8
EmergencyShutdown............................................9

8320SeriesTenuline®Attenuator
ix
Chapter 5 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
RFAssemblyResistanceTest.....................................10
DCResistanceMeasurement..................................10
PreventiveMaintenance.........................................12
PeriodicInspection..........................................12
CleanOutsideSurfaces.......................................12
CleanConnectors............................................12
Troubleshooting................................................13
RepairProcedures..............................................14
CoolantLeakageRepair.......................................14
ReplaceRFConnector........................................14
ReplaceCoolantTankOutputEndCoverSeal.....................14
ReplaceCoolantTankInputO‐ringSeal.........................17
ReplaceRFAssembly.........................................18
CoolantLevelInspection......................................18
Storage.......................................................19
CustomerService...............................................20
Shipping......................................................20
Chapter 6 Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Specifications..................................................21
ReplacementParts
.............................................22
AvailableQCTypeConnectors.................................23
Limited Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

1
Chapter 1 Introduction
General Description
TheSeries8320Tenuline Attenuatorarelowreflectionresistancenetworksfor
useinreducingRFpowerin50ohmtransmissionlinesbyknownandcontrolled
amounts.See"OutlineDrawing"onpage2.
OverthefrequencyrangeofDCto500MHz,thepoweroutputwillbereduced
by30dB(99.9percent)±0.5dB.Upto500MHz,theinputVSWRwillnotexceed
1.1andtheoutputVSWR1.15.Theseattenuatorsareusefulforloweringahigh
inputRFpowertoalevelsuitableforfeedingintoascope,frequencycounteror
similardevice.
Theyareself‐containedinstrumentsthatrequirenoexternalsourceofpoweror
utilityservice.
Allmodelsareportableandhaveaconvenientcarryinghandlenestedamong
thecoolingfinsonthetopside.Ifdesiredtheattenuatormaybepermanently
mounted,see"Mounting"onpage6.
Operating Environment
TheTenuline Attenuatorsshouldbeoperatedinadustandvibrationfree
environment.
Theyrelyonlyonambientaircurrents,theseattenuatorswillsafelyabsorb,and
dissipate,uptotheirmaximumratedinputpower.Theradiatorshavingcooling
finsspacedevenlyalongtheirlengthstoefficientlydissipateheatgenerated
duringoperation.
Allowatleast6inches(150mm)ofclearancearoundtheunittoallowsufficient
convectionaircurrentsforadequateheatdissipation.Theambienttemperature
rangeshouldremainbetween‐40°Cand+45°C(‐40°Fand113°F)forproper
operation.See"Specifications"onpage21fortheratedpower,dimensionsand
weightoftheattenuators.

8320SeriesTenuline®Attenuator
2
RF Connectors
TheSeries8320AttenuatorsareequippedwithaBirdQuick‐Change(QC)
connectors.
FemaleNtypeconnectorsarenormallysuppliedfortheinputandoutputbut
maybeconvenientlyandeasilyinterchangedwithotherBirdQCconnectors.See
"AvailableQCTypeConnectors"onpage23foralistofavailableconnectors.See
"ReplaceRFConnector"onpage14forreplacementinstructions.
Figure 1 Outline Drawing

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
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'(""
%)$'
*!+
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./.#0%!#
#%
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
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*!+
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./.#0%!#
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$&$
+"2
#$03"
Note: Model8325isshowninFigure1.

3
Chapter 2 Theory of Operation
TheSeries8320maybeusedfortheisolationofpowersourcesuptotheir
maximumpowerratingandforlowlevelmonitoring.Thelowpowervalue
obtainedattheoutputoftheattenuatorcaneasilybefedintoanoscilloscopeor
terminatedinasmallRFloadresistor.
Attenuator Construction
TheSeries8320Attenuatorsaresymmetrical“T”pads,withthepower
distributiononthelegsbeingdifferent.Thevalueoftheresistanceoneachleg
varies;therefore,accordingtothepoweritistoabsorb.Ontheinputresistance
element,aproportionatelylargerresistorisofcourserequiredforitsmuch
greaterpowerdissipation.A“T”configurationisusedtoprovideequalinputand
outputimpedancesforthe50ohmtransmissionlineattenuation.
Theinputresistorisjoinedtothe“T”legjointinanexponentiallytapered
housingtoprovidealinearreductioninsurgeimpedancedirectlyproportional
tothedistancealongtheresistor.Theoutputresistorisenclosedinahousing
designedtoreturntheattenuatortothecharacteristicimpedanceof50ohms.
Thisarrangementproducesauniformandpracticallyreflection‐lessattenuation
characteristicoverthestatedfrequenciesoftheattenuator.
Thissystemoffilm‐on‐ceramiccylindricalresistorsimmersedinadielectric
coolantconstitutestheRFAssembly.Thedielectricconstantofthecoolingfluid
andthetaperedinputandoutputresistorhousingsprovidetheproperelectrical
characteristicsforthecoaxiallineattenuationthroughouttheinternalcircuitry.
Cooling
Thedielectriccoolantiscarefullychosenforitsdesirabledielectricproperties,to
whichthediametersoftheresistorsandhousingsarematched,andforitshigh
thermalstabilitycharacteristics.
Thecoolantusedis10CTransformerOil,P/N5‐030.
Model8321requiresapproximately1pint(0.47liter)
Model8322,0.7gallons(2.65liter)
Model8323,0.35gallons(1.3liter)
Model8325,0.9gallons(3.4liter).

8320SeriesTenuline®Attenuator
4
Coolant Expansion
Models8321,8322and8323allowforexpansionofthecoolantbyusingunder‐
filledradiatortanksandaderatingoftheirloadcarryingcapacities.
Model8325includesanexpansiontankandaventpluglocatedontheoutput
endatthetop.Whenpowerisappliedtotheattenuator,thecoolantexpands
intotheexpansiontank,astheairintheexpansiontankiscompresseditis
allowedtoescapethroughtheventplug.
Heat Dissipation
HeatDissipationisaccomplishedbyconvection,thecoolingfluidcarriestheheat
generatedintheresistorelementstothewallsofthecoolanthousing.This
housingisencasedinasetofradiatingfinswhichareattachedtoitsouter
surface.Theseradiatingsurfacesdissipatetheheatofthecoolantintothe
surroundingair.

5
Chapter 3 Installation
Unpacking and Inspection
1. Carefullyinspectshippingcontainerforsignsofdamage.
Iftheshippingcontainerisdamaged,donotunpacktheunit.
ImmediatelynotifytheshippingcarrierandBirdTechnologies.
Iftheshippingcontainerisnotdamaged,unpacktheunit.Save
shippingmaterialsforrepackaging.
2. Inspectunitforvisualsignsofdamage.
Note: Ifthereisdamage,immediatelynotifytheshippingcarrier
andBirdTechnologies.
Location
TheSeries8320TENULINE®Attenuatorsshouldbelocatedtoallowoperationin
thehorizontalpositiononly,withthehandleupandmountingbracketsdown.
Allowatleastsixinches(150mm)ofclearancearoundtheunitinanareawith
freelycirculatingambientair.Unimpededairflowofconvectionaircurrentsis
requiredforadequateheatdissipation.
Positiontheattenuatortopermittheshortestpossiblecablelengthsbetween
theunitandthetransmittingequipment.
Theattenuatorisnotintendedorrecommendedforoutdoorusewhereitwillbe
unprotectedandexposedtotheelements.
CAUTION
TheAttenuatorisdesignedtobeoperatedinthehorizontalposition,with
mountingbracketsdown.
Operationinanyotherorientationwillcauseinsufficientcoolingoftheunit
leadingtoprematurefailure.

8320SeriesTenuline®Attenuator
6
Mounting
Theattenuatorisdesignedforeitherportableoperationorfixedinstallation,
thatis,itmayoperatedwithorwithoutbeingsecuredtoabenchorother
horizontalsurface.
Model8321isequippedwithrubberbumperfeetwhichcanberemovedfor
permanentmounting.Theholesaretappedfor8‐32screws.
ForModels8322,8323and8325,thefrontandrearfinsaremadeofheavier
gaugematerialbentoutward90toformmountingflanges.Ateachcornerof
theseflangesisa9/32inch(7mm)diametermountinghole.Theholesare
arrangedinarectangle,see"Specifications"onpage21forthedimensions.The
attenuatormaybesecuredtoahorizontalsurfaceusingcustomerprovided
screws,nutsandlockwashers.
Setup
Vent Plug Installation (Model 8325)
BeforeplacingtheModel8325Attenuatorintoservice,thesolidshippingplug,
P/N2450‐049mustberemovedandreplacedbythespringloadedventplug,
P/N2450‐094.Thetwoplugsarelinkedtogetherbyapieceofbeadchain.
1. Locatetheventholefortheplug,locatedonthetopneartherear.
SeeFigure1onpage2.
2. Removetheshippingplug.
3. VerifytheO‐Ringisinstalledontheventplug.
4. Installtheventplug
5. Retaintheshippingplugforuseintransportingtheattenuator.
Theshippingplugshouldbeplacedbackintheventholewheneverthe
attenuatoristobeshipped.TakecarenottolosetheO‐Ringseal.
WARNING
Theventplugmustbeinstalledatalltimeswhentheunitisinoperationor
cooling.Alwayschecktoensureventplugisinstalledpriortooperation.
Failuretodothiscouldresultindamagetotheequipmentandendangerthe
operator’ssafety.

Installation
7
Installing in a 50 Ohm Line
Models8322,8323and8325arelabeledINPUTandOUTPUTontherespective
ends.
Model8321islabeledontheoutputendonly.
Theproperendsoftheseattenuatorsmayalsobeidentifiedbytheinput
connectorbeingmountedontheflatgoldcoloreddiscwhereastheoutput
connectorismountedontheroundedsilvercoloreddome.
CAUTION
1. PerformtheRFAssemblyTestontheAttenuator,see"RFAssembly
ResistanceTest "onpage10.
2. Connectthetransmittingequipmentundertesttotheinputofthe
attenuator.
Use50ohmcoaxialcabling(RG‐8A/U,RG‐9/U,RG‐213/Uorequivalent)
equippedwithplugswhichmatewiththeconnectorsontheattenuator.
3. Connecttheoutputtoasuitableload.
4. Proceedaccordingto"OperatingInstructions"onpage8.
Note: Whenreconnectingtheantenna,itmaybecomenecessary
toslightlyreadjustthetransmitterduetopossibledifferencesin
VSWRbetweentheattenuatorandtheantennasystem.
WARNING
LeakingRFenergyisapotentialhealthhazard.
Neverattempttoconnectordisconnectequipmentfromthetransmission
linewhileRFpowerisbeingapplied.
Severeburns,electricalshock,ordeathcanoccur.
Theinputandoutputendsoftheseattenuatorsareclearlylabeled.Donot
coupleanattenuatorbackwardstothedirectionofpowerflow.Destructionof
theoutputresistorwillresult.

8
Chapter 4 Operating Instructions
TheSeries8320TENULINE®Attenuatorsshouldfunctionfaultlessly,absorbing
andconvertingRFenergyintoheatindefinitely,iftheyareproperlymaintained
andnotsubjectedtoanoverload.
Normal Operation
Note: TheSeries8320TENULINE®Attenuatorsarenotintendedor
recommendedforoutdoorusewheretheywillbeunprotectedand
exposedtotheelements.
1. Installtheattenuatorinthetransmissionline,see"Installingina50Ohm
Line"onpage7.
2. (Model8325)VerifytheVentPlughasbeeninstalled,see"VentPlug
Installation(Model8325)"onpage6.
3. Proceedaccordingtothetransmittermanufacturer’sinstructions.
Theattenuatormaybesubjectedtoverymoderateoverloadsforlimited
periodsoftimewithoutoverheating.However,thisshouldbedonevery
cautiouslytoguardtheattenuatoragainstthedangersofoverheating.
CAUTION
Theinputandoutputendsoftheseattenuatorsareclearlylabeled.Donot
coupleanattenuatorbackwardstothedirectionofpowerflow.Destructionof
theoutputresistorwillresult.
WARNING
Theventplugmustbeinstalledatalltimeswhentheunitisinoperationor
cooling.Alwayschecktoensureventplugisinstalledpriortooperation.
Failuretodothiscouldresultindamagetotheequipmentandendangerthe
operator’ssafety.
WARNING
Usingtheattenuatorintheupperendofitspowerdissipationrangewillcause
thehousingtobecomehot!
Careshouldbeexercisedintouchingthem.

OperatingInstructions
9
Emergency Shutdown
Shouldtherebeanyabnormaloperationorfailureoftheattenuator,shutdown
thetransmitterimmediatelyandallowtheunittocoolbeforeperformingany
maintenance.
1. DisableRFpoweratthetransmitter.
WARNING
LeakingRFenergyisapotentialhealthhazard.
Neverattempttoconnectordisconnectequipmentfromthetransmission
linewhileRFpowerisbeingapplied.
Severeburns,electricalshock,ordeathcanoccur.

10
Chapter 5 Maintenance
RF Assembly Resistance Test
Note: Thesetestsarebynomeansanecessitytotheoperationof
theattenuatorbutmerelyguidelinesfortheusersinformation.
AccuratemeasurementoftheDCresistancebetweentheinputtoground,
outputtoground,andinputtooutputwillprovideagoodcheckofthecondition
oftheattenuator.
CheckingtheDCresistanceissimplyusedtomeasureachangeintheresistance
overtime.TrackingtheDCresistanceshouldstartbefore theunitisfirstputinto
service.Performthefollowingstepsandrecordthevalueforfuturecomparison.
Resistancemeasurementsshouldbetakenperiodicallyaccordingtouse.
Preparation:
Tools:Commonhandtools.
Ohmmeterwithanaccuracyof±1%at50ohms(orusearesistance
bridge).
Uselowresistanceleads,preferablyashortpieceof50ohmcoaxial
cablefittedwithanappropriateconnectororalligatorclips.
Temperatureoftheattenuatorshouldbestabilizedbetween20°Cto
25°C(68°Fto77°F).
DC Resistance Measurement
Note: Itisrecommendedthatthisresistancecheckbeperformed
eachtimetheattenuatoristobeused.
1. TurnoffRFpowerbeforemakinganydisconnections.
2. DisconnecttheRFcoaxialline.
3. Takethefollowingmeasurements:
WARNING
NeverattempttoconnectordisconnectRFequipmentfromthetransmission
linewhileRFpowerisbeingapplied.
LeakingRFenergyisapotentialhealthhazard.