HP-415B-Manual 电路图.pdf

《HP-415B-Manual 电路图.pdf》由会员分享，可在线阅读，更多相关《HP-415B-Manual 电路图.pdf（36页珍藏版）》请在收音机爱好者资料库上搜索。

1、 HP Archive This vintage Hewlett Packard document was preserved and distributed by www. Please visit us on the web ! On-line curator: Daniel Sheen RadioFans.CN 收音机爱 好者资料库 l -, .:. OPERATINGAND.SERVICINGMANUAL r#jJ STANDINGWAVEINUICATOR (1-lr9 RadioFans.CN 收音机爱 好者资料库 OPERATINGANDSERVICINGMANUAL FOR M

2、ODEL415B STANDING WAVE INDICATOR SERIAL4183 AND ABOVE ( I , ;. .t CopyrightHEwLETT-PACKARDCOMPANY1955 275PAGEMILLROAD,PALOALTO,CALIFORNIA,U.S.A. 415B002-4 RadioFans.CN 收音机爱 好者资料库 FREQUENCY: SENSITIVITY: NOISELEVEL: AMPLIFIERQ: CALIBRATION: RANGE: SCALESELECTOR: .METERSCALES: GAINCONTROL: INPUT: RECO

3、RDEROUTPUT: lNPUTCONNECTOR: POWER: DIMENSDNS: WEIGHT: ACCESSORIES FURNISHED: i.CCESSORIESAVAILABLE: SPECIFICATIONS 1000cps2%.Otherfrequencies315to2020cpsavailableonspecial order. 0.1Jivata200ohmlevelforfullscaledeflection. Lessthan0.03J.vref.toinputoperatedfroma 200ohmresistorat roomteperature. 255.

4、 Squarelaw.MeterindicatesSWR,db. 70 db.Inputattenuatorprovides60 db in10dbsteps.AccuracyO.1 db per10dbstep.MaximumcumulativeerrorO.2 db. NormalExpandand-5db. SWR1-4SWR3-10,ExpandedSWR 1-1. 3,db0-10,Expandeddb0.2. Adjuststoconvenientreferencelevel.Rangeatleast10db. Bolo(200ohms).BiasprOVidedfor8.4rna

5、bolometerof 1/100amp fuse;or4.3rnalowcurrentbolometer. Crystal.200ohmsforcrystalrectifier. 200,000ohms.Highimpedanceforcrystalrectifierasnulldetector. JackprOVidedforrecordingmilliammeterhaving1 rnafullscaledeflec- tioninternalresistance.of1500ohmsorless. BNC. 115/230volts10%60cps,55watts.Otherfrequ

6、enciesonspecialorder. CabinetMount:7-1/2wide11-1/2high,12-1/4deep. RackMount:19 Wide,7high,11-3/4deep. CabinetMount:Net13Ibs.Shipping19Ibs. RackMount:Net18Ibs.,Shipping30Ibs. 4lA-16ECableAssembly. 415B-42BPlug-inFilter315-700cps. 700-2020cps. AC-16DCableAssembly,44inchesofRG-58/U50ohmcoaxialcable te

7、rminatedatoneendonlywithaUG-88/UTypeBNCmaleconnector. AC-16KVideoCableAssembly,4feetofRG-58/U50ohmcoaxialcable terminatedateachendwithUG-88/UTypeBNCmaleconnectors. Sect.IPage1 SECTIONI GENERALDESCRIPTION 1-1INTRODUCTORY Inhighfrequencyapplications,standing-wavemea- surementsarethecustomarymeansofinv

8、estigating theimpedancematchoftransmissionsystems, varioustypesofterminationssuchasantennasand loads,andoth21high-frequencydevicessuchas connectors,transitions,etc.TheModel415B standingWaveIndicatorisalaboratory-qualityin- strumentdesignedprimarilyforuseinmakingac- curatestanding-wavemeasurementsinc

9、onjunction withasuitabledetectorprobeandslottedcoaxial andwaveguidesections.The415Bcanalsobeused asadetectorinbridgecircuitsandforotherap- plicationsrequiringaverysensitivefixed-frequency indicator. 1-2DESCRIPnON TheHewlett-PackardModel415BStandingWave Indicatorisahighlysensitive,fixed-frequency ele

10、ctronicmetercalibratedtoindicatedirectlyboth voltageandpowerstanding-waveratioswhenused withsquarelawdetectorssuchascrystaldiode! andbarretters.Expandedmeterscalesareprovided foreasyreadingofextremelysmallincrements. ThehighlyaccurateinputRANGEswitchpermits range-to-rangereadingwithoutlossofaccuracy

11、. Becauseofthelownoiselevelinthe415B,measure- mentofsignallevelstobelowO.1microvoltispos- sible. Afrontpanelselectorswitchadaptstheinputcir- cuitofthe415Btoeitheracrystaldiode, abarret- telorahighimpedancesignalsource.Forbar- retters,thecorrectbiascurrentisautomatically suppliedthroughtheinputjack,t

12、hecurrentvalue beingselectedbyatoggleswitchforeitherof two differentbarretterresistancesincommonuse. The415Brespondstoasinglefrequencyonly, 1000 cyclespersecond.Thefrequencymaybechanged inthefieldbyinstallinganewplug-infiltertuned tothedesiredfrequency,nofurtheradjustmentbeing required.Plug-infilter

13、stunedtofrequenciesbe- tween315and2020cyclesareavailablefromthe Hewlett-PackardCompany,onspecialorder. ProvisionismadeintheModel415Bforpassing themetercurrentthroughanexternalrecorder. Thiscurrentcanalsobeusedtooperateearphones oranoscilloscope. 13ELECTRICAL CHARACTERISTICS TheModel 415B Standing Wa

14、veIndicatorisdesigned andcalibratedtomeasureasignal-obtainedfrom square-lawdevicessuchascrystaldiodes(atlow signallevels)andbarretters;however,itmayalso beusedasapeakornullindicatorinconjunction withlinearsignalsources.Theindicatingmeter iscalibratedtoindicatestandingwaveratiodirectly invswrandindba

15、ndincludesexpandedscalesfor veryaccuratereadingsofsmallincrements.The range-to-rangeaccuracyiswithin0.1dbbetween eachrange.Themaximumsensitivityofthe415B (whensetforCRYSTALorBOLOoperation)is0.1 microvoltforfullscalemeterdeflection.Thenoise levelislessthan0.03microvoltasreferredtoa signalobtainedfrom

16、a 200ohmresistorconnected totheinput jack.Usefulmeasurementsmaybemade downtotheactualnoiselevel. Thesensitivityofthe415Bisvaried10dbstepsover arangeof60decibelsbythefrontpanelRANGE switch.TheGAINcontrolprovidesafurtherad- justmentofthesensitivityoveranapproximate12. 5 decibelrangetoobtainaconvenient

17、meterreading forany inputsignallevel.TheEXPAND-NORMAL- 5DBswitchselectsanexpandedmeterscalewhen desiredandinthe-5dbpositionshiftsthemeter readingdownscale by 5 dbsothatreadingsnormally readfroma downscalepositioncanbereadupscale onthenextlowerstepontheRANGEswitch. Theinternalimpedanceofthe415Basseen

18、atthe INPUTjackiseither200ohms,or200,000ohms asselectedby the BOLO-CRYSTAL-200, 000selector switch.WhensettoBOLO, ad-cbiasofapproxi- mately8.4milliamperesisautomaticallyapplied toa 200-ohmbarretterconnectedtotheINPUTjack. Sect.IPage2 Atoggleswitchonthefrontpanelchangesthebias currenttoapproximately4

19、.3milliamperes.The BOLOCURRENTjackonthefrontpanelpermits thebiascurrentsuppliedtotheexternalbarretter tobemonitoredbyanexternalmeteranddecreased byinsertionofaddedseriesresistance. The frequency ofthe415BassuppliedfromHewlett- PackardCompanyis1000cyclespersecond2%with abandwidthofapproximately38cycl

20、esatthehalf powerpoints.Theselectivityofthetunedamplifier isdeterminedbyasingleplug-infilterhavingan effectiveQbetween20and30. Thefrequency oftheamplifiermaybechangedwith- outadjustmentbyinstallinganewfiltertunedtothe desiredfrequency.TheRECORDERjackonthe front panel provides sufficientsignalcurrent

21、tooper- atea 1milliampererecorder(orotherindicating device) having an inputresistanceof 1500ohms.The currentthroughtherecorderisthesamecurrent thatflowsthroughthevswrmeter. The415Boperateson115voltor230volt,60cycles a-cpowerandconswnes55wattsofpower.Thein- strumentisnormallysuppliedwitha 1ampere Slo

22、-Blofuse.For230voltoperationuseaO.5 amperefuse. 14APPLICATIONS ThetiJModel 415BStandingWaveIndicatorhasbeen specificallydesignedforusewiththe!5f;seriesof SlottedLinesandDetectorMounts.Acomplete seriesofSlottedLineequipmentforimpedanceand swrmeasurementsincoaxialandwaveguidetrans- missionsystemsisava

23、ilabletocovertheentire frequencyrangefrom500meto18kmc.Also availableisaconvenientlineofwaveguideand coaxialDetectorMountsfortherangefrom10me to12.4kmc.Table1-1showsthevariousHewlett- Packardinstrumentsfortheseservicesarrangedby frequencycoverage. -SLontINE-. TYPE NSYSTEM INSTRUMENTSUSEDWITHTHE4158ST

24、ANDINGWAVEINDICATOR foo- 805B -SLOTTEDLINE-0 t) l;COAXIALStSTEM lJ I II806BIII . -.I I .ICOAXIALSLOTTEDSECTION.TYPENSYSTEM 1+tTI I 10.: f+-S810A.t-GBIOB-+lJ810BXBIOBP810B I-. WAVEGUIDE WAVEGUI!WAVEGUIDEWAVEGUIDESLOTTEDWAVEGUIDE SLOTTEO SECTION CSLOTTEDSLOTTEDf-SLOTTEDISECTION -.I SECTION ,nNt t) _._

25、.-_._._.- H810BNOTE5 _._._.f.-_e_-f.-=-tf-e- Requires444AWidebond Probe. _._.- Requires440ADetector mounte. .- Io-S4B5. G485J48/:!X4BB 422BBroadband Probe. WAVEGUIDEWAVEGUIDEWAVEGUIDEWAVEGUIDERequires809BUni,ersol Probe DETECTORDETECTORrl-DETECTORDETECTOR Conioge,444ABroadband Probe. MOUNTMOUNTMOUNT

26、MOUNT )UsesBorretter. ,I II WAVEGUIDE U.,.BorretterorCrystal. DETECTOR MOUNT 476A X421A t) BOL.TUNABLEWAVEGUIDE MOUNTBOLOMETER+-CRYSTAL DETECTORP421A Q: MOUNT 420AMOUNT WAVEGUIDE C CRYSTALDETECTOR I-. WIDEBANDCRYSTALDETECTOR I MOUNT ,TYPE N SYSTEM .) II lJ 440ADETECTORMOUNT,422BBROADBANDPROBE ., I-.

27、 lJ FORWAVEGUIDE SLOnEDECTIONS C 444A BROADBANDPROSE I FORWAVEGUIDE SLOTTED SECTIONS IITI o23456 78910II12131415161718 rREOUENCY.KMC Table1-1.Suitable/4, LOADEQUALSr.oVSWR LOAD MINIMUM :/ MINIMUMWILLSHIFTTO V MINIMUMWILLSHIFT TO THIS REGION IF LOAD THISREGIONIFLOAD IS INDUCTIVE SCAPACITIVE I LOAD +

28、4 IFMINIMUMDOESNOT SH IFT,LOADEQUALSr.c!VSWR Figure2-8.SummaryofRulesforImpedanceMeasurement ( Sect.IIPage9 -t +-SHORT 04-LOAD And:Ad=Shiftincentimetersoftheminimum p:intwhentheshortisapplied. Figure2-9.GraphShowingStandingWavePatternswithaLoadandShort- zL Where:X A 2 1 -j(VSWR)TanX (VSWH) -iTanX dt

29、akesapositive(+)signwhen theminimumshiftstowardtheload. dtakesanegative(-)signwhen theminimumshiftstowardthegen- erator. One-halflineorguidewavelength. nisthedistanceincentimetersas measuredbetweentwoadjacent minima. 2-13IMPEDANCE MEASUREMENT ANDTHE SMITH CHART Whendataisobtainedfromslottedlinemeasu

30、re- ment,one ofthemostindispensabletoolsandcer- tainlythesimplesttouse,istheSmithChart.This chartrepresentsanimpedancecoordinatesystem soarrangedthatthevariablequantitiesinimpedance relationshipsareconvenientlydisplayedforthe solutionoftransmissionlineproblems.* Thevaluesofresistanceandreactanceshow

31、non theSmithChartinFigure2-10arebaseduponthe normalizedvalues.Thenormalizedimpedance, resistanceorreactanceisobtainedbydividingthe actualvaluebythecharacteristicimpedanceofthe line.Forexample,iftheactualimpedanceofa50 .ohmtransmissionlinewerefoundtobe100ohms atsomepoint,thenormalizedimpedancewouldbe

32、2. ThecirclesontheSmithCharttangenttobottomof thechartarecirclesofconstantandnormalized resistance. Thesecalculationsarebasedupontheassumption thatnolossesoccurinthetransmissionsystem. Forlaboratoryset-upswherethelinelengthsare shortthisassumptioniscustomary.Itisalsoas- sumedthattheZoforthelinesisen

33、tirelyresistive. *Smith,P.H.Transmission-lineCalculator Electronics,Jan.1939,McGraw-Hill. Ragain,G.L.Ch.2,Vol.9M.I.T.Had.Lab. Series,1948,McGraw-Hill. Sect.IIPage10 Thestraightlineformingtheverticaldiameterof thechartisthelineofzeroreactance.Totheright andleftofthislineareseenlineswhichcurveaway fro

34、mthezeroreactanceline.Thecurvedlinesto therightarethelinesofpositivereactance+ jX. Zo Thecurvedlinetotheleftarethelinesofnegative reactance,- jX . Forexample,theimpedance point of alineterminated byitscharacteristicimpedance wouldbethecenterof thechart(Withanormalizedresistanceof1.0and no reactiveco

35、mponent). Inanotherexampleofactualimpedancecalculation: ZL=5+j25ohms Normalizedfora50ohmlinewould be: zN=0.1+ jO.5 2-14PROCEDURE FOR SMITH CHART CALCULATIONS ThestepbystepprocedureforemployingtheSmith Chartwhensolvingtransmissionlineproblemsis outlinedbelow.Itshouldbeunderstoodthatthere arevariousme

36、thodsemployedforenteringtheSmith Chartwithdataobtainedfromtheslottedline,and thatthemethodoutlinedinthissectionhasbeen foundpracticalandsimple. a.Setupslottedlineinsystem. b.Measurevswrinmannerdescribedinsection2-5. g.Determinethenumberofwavelengthofshift (.a.). .ld AL h.StartingatcenterofSmithChart

37、drawcircle withvswrasradius.Readvswronzeroreac- tancelinedownfromcenter. i.EntertheSmithChartatthetopandproceed- inginadirectionofprobemovement(either towardtheloadortowardthegenerator)whenthe loadwasreplacedbyashorttothequantity.lA establishedinstepg. j.Drawalinetothecenterofthechartfromthe .a.poin

38、t. k.Theintersectionofthislineandthevswrcircles isthenormalizedimpedance. 1.Itisimportantthattheconventionbefollowed offirstfindingtheminimumreferencewiththe loadonthelineandthenslidingtheprobetothenew minimum whenthelineisshorted.Shoulditbeneces- sarytoestablishtheshortedminimumpointfirst,the Smith

39、ChartwouldbeenteredwithA.inadirection oppositetothedirectionofprobemovement.That is,theprobemovementtowardtheloadwouldbe enteredonthechartinadirectiontowardthegener- ator. m.Anexamplewillclarifythisprocedure. Thevswrismeasuredas3.3. Thedistancebetweentwoadjacentminimais15em. .Therefore,thewavelength

40、ofthelineis30em(AL) Aconvenientminimumislocatedat22em. Thelineisshorted. Theminimum pointshiftsto19em(towardgenerator). ( .ld=22 -19=3emc.Determinewavelengthoftransmissionline (.L).Paragraph2-8showedthatthedistance asmeasuredonslottedlinebetweentwoadjacent minimawasequaltoone-halfthewavelengthofthe

41、line. .a.3/300.1wavelength d.Findaconvenientminimumpoint. e.Replaceloadwithshort. ConstructvswrcircleonSmithChart.SeeFigure 2-10. Constructradiustowavelengthshiftpoint.See Figure2-11. f.Measure.ld(theshiftincentimetersofthe minimumpointwiththeshortapplied). Read impedanceatintersectionatpointAonFigu

42、re 2-12.Normalizedimpedanceequals.44+jO.64. RW7fP Sect.IIPage11 Figure2-10.SmithChartwithConstructedVSWRCircle,VSWR3.3 Sect.IIPage12 ( . . ., 0? .;,; . I 0 . 0 ?. 0 .; i: f ;: . Figure2-11.SmithChartwithWavelengthShiftPointConstructedasaRadius.AA -0.1 Sect.ITPage13 Figure2-12.SmithChartShowingImpeda

43、ncePoint,A (l I, II 1 IINPUTI lVSWR INPUT - 115DBMETER TRANSFORMER SELECTIVECb AMPLIFIER (300BGAIN) AMPLIFIER VIV2 V3 POW ERSUPPLY POWER 115/230VAC TRANSFORMER RECTIFIERSERIESTUBE +240VDC - TI V4V5 REGULATED AMPLlfl.ER V6 REFERENCE TUBE V7 CHASSIS GROUND Figure 3-1,Mode1415BBlock Diagram (J) 11l n .

44、 S Id PJ aq 11l o ;, . = Sect.illPage1 SECTIONIII THEORYOFOPERATION 31CIRCUIT DESCRIPTION TheModel415BStandingWaveIndicatorconsists ofahigh-gainamplifier,a 1000cycleresonantcir- cuit,anindicatingmeterandanelectronicallyregu- latedpowersupply.Alltubesoftheinstrumentare shownintheblockdiagraminFigure3

45、-1.Basically, operationoftheinstrumentisasfollows: a.Afour-stage,frequencyselectiveamplifier amplifiestheinputsignalamaximumof115 decibelsforapplicationtotheindicatingcircuit. Thesensitivityoftheselectiveamplifierisad- justedbytwofrontpanelcontrols,theSWR-DB RANGEselectorandtheGAINcontrol. b.The1000

46、-cyclesignalfromtheselectiveampli- fierisfedtoafeedbackamplifierwhichinturn operatesthevswrmeter. c.Allcircuitsarepoweredfromtheelectronically regulated+240-voltpowersupply. 3-2FRE9UENCYSELECTIVEAMPLIFIER Thefrequencyselectiveamplifierconsistsof31:1 step-upinputtransformerT2,threeresistance coupledh

47、i-mutriodestagesandafourthstagewhich isplatetunedto1000cps.Theamplifierwithout theinputtransformerprovidesatotalof115-db gain,whileT2providesanadditional30db. Theinputcircuittotheselectiveamplifierisar- rangedtomatchvariousexternalsignalsourcessuch asacrystaldiode,barretterorarelativelyhigh- impedan

48、cedevice(bridgecircuit,etc.).Whenthe inputcircuitisswitchedto200KnCRYSTALtheinput jackconnectsthroughtheSWR-DB RANGEswitchS5 tothegridofthefirstamplifiertube.Inthe2000 CRYSTALpositiontheINPUTjackconnectstothe primaryofT2whichprovidesareflectedloadof 200ohmstoanydeviceconnectedtotheINPUTjack. IntheBO

49、LO.positiontheinputjackconnectstothe primaryoftheinputtransformerasabove;except thattheprimarywindingisnowreturnedtoacur- rentsource,R2andR3,providingd-coperating biasthroughthetransformerwindingtoany 200ohm detectorelementconnectedtotheinputjackThe HIGH-LOWtoggleswitchshuntsthecurrentsource withRIsothattwodifferentvaluesofbias(4.3and 8.4milliamperes)maybeused.Thebiascurrent isfedalsothroughajackonthefrontpanelsothat anexternalmilliammetermaybeusedtomeasure thebiascurrentpassingthroughthe