HP-712B-Manual-SNprefix-002 电路图.pdf

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1、HP Archive This vintage Hewlett Packard document was preserved and distributed by Pleasevisituson the web! Scanned by on-line curator: Tony Gerbic * For FREE Distribution Only * RadioFans.CN 收音机爱 好者资料库 7128 REGULATEDPOWERSUPPLY SERIAlSPREFIXED:002- OPERATINGANDSERVICINGMANUAL PRINTED12-51 RadioFans.

2、CN 收音机爱 好者资料库 OPERATINGANDSERVICINGMANUAL FOR MODEL 7128 POWERSUPPLY SERIALPREFIX:002- HEWLETTPACKARD COMPANY 275 PAGE MILL ROAD, PALO ALTO, CALIFORNIA, U.S.A. 7128004-2 RadioFans.CN 收音机爱 好者资料库 TABLEOFSPECIFICATIONS OUTPUTVOLTAGES DCREGULATEDHIGHVOLTAGE: DCREGULATEDFIXEDBIAS: DCVARIABLEBIAS: ACUNREG

3、ULATED: oto+500volts(withoutswitching),200mamaximumload. -300volts,50mamaximumload. oto-150volts,5mamaximumload. 6.3voltsCT,10ampsmaximumload. OUTPUTVOLTAGEREGULATION(forconstantlinevoltage) DCREGULATEDHIGHVOLTAGE: DCREGULATEDFIXEDBIAS: DCVARIABLEBIAS: LINEVOLTAGEREGULATION RIPPLE INTERNALIMPEDANCE

4、DCREGULATEDHIGHVOLTAGE: RECOVERYTIME METERING CURRENTMETER: VOLTMETER: TERMINALS OVERLOADPROTECTION POWERSUPPLY DIMENSIONS WEIGHT Lessthan50millivoltschangeno-loadtofull-loadatanyoutput voltage. Lessthan50millivoltschangeno-loadtofull-load. Istiedtofixedbias,hencesourceregulationissameasforfixed bia

5、s.Internalimpedance0to10,000ohms,dependingonbias controlsetting. RegulatedDCoutputvoltagesvarylessthanl00millivolt.for linevoltagevariations115voltslOo/a. Lessthan500microvolts. (Forfrequenciesabove20cps.)Full-load:0.1ohminseries with25microhenriesmaximum.No-load:1ohminserieswith 50microhenriesmaxim

6、um. Uponapplicationoffull-load:0.1millisecondmaximum.Upon decreasefromfull-loadto: (a)0ma,0.5millisecondmaximum. (b)25ma,O. 1millisecondmaximum. Maximumtransientvoltage,1volt. oto200mao(highvoltageonly.) Threeranges,0to+500volts,0to+150voltsand0to-150volts. PanelswitchconnectsmetertoDCregulatedhighv

7、oltageorDC variab.!ebiasandselectsrange. EitherpositiveornegativeDCregulatedhighvoltageterminalmay begrounded.Positiveterminalsofbothbiassuppliesandnega- tiveterminalsofDCregulatedhighvoltagearecommon. ACline,DCregulatedhighvoltage,DCregulatedfixedbiasand filamentsupplyareseparatelyfused.DCregulated

8、highvoltage dropstoasafevalueifbiasfuseblows. 115volts10%,50to60cps.Approximately120to450watts dependingonloadandlinevoltage. CabinetMount.:12-3/4high,20-3/4wide,l4-/4deep. RackMount:Panel10-1/2high,19wide,13-11411deep behindpanel. CabinetMount:70lbs.shippingweightapprox.91lbs. RackMount:62lbs.shipp

9、ingweightapprox.85lbs. Para. TAILE OF CONTENTS FOR MODEL 7121 POWERSUPPLY Para. 1-1 1-2 2-1 2-2 3-1 3-2 3-3 SECTIONI GENERALDESCRIPTION General Inspection. SECTIONII ControlsandTerminals. Operation SECTIONIII General. HighVoltageRegulator Circuit BiasSupplyCircuit. 1-1 1-1 2-1 2-2 3-1 3-1 3-3 4-1 4-

10、2 4-3 4-4 4-5 4-6 4-7 4-8 SECTIONIV MAINTENANCE CoverandBottomPlate Removal Replacements Adjustments LineRegulation Adjustment AdjustmentofFixed-300 VoltBiasSupplyOutput Voltage AdjustmentOfHVSupply OutputVoltage SettingVariableResistor R39. SettingtheStopontheH V Control 4-1 4-1 4-3 4-3 4-5 4-5 4-5

11、 4-7 SECTIONV TABLEOFREPLACEABLEPARTS SECTION I GENERAL DESCRIPTION CAUTION Voltageswhicharedangeroustolife arepresentattheterminalsand withinthisinstrument. I-IGENERAL TheModel712BPowerSupplyisaverystable sourceofcontinuouslyvariabledirectcur- rentforplateandbiascircuits.Italsopro- videsupto10amper

12、es,6.3voltsalternat- ingcurrentforfilamentcircuitsAtwo- rangevoltmeterandamilliammeter(high voltageonly)areprovidedtomeasurethe directcurrentoutput.Thispowersupplyis veryusefulasapowersourceforsmalltrans- mitters,oscillators,complexsystems,cer- taintypesofklystrons,andgenerallabora- toryuse. CAUTION

13、 TheACpowershouldbeturnedon foratleast30secondsbeforeswitch- ingonthehighvoltage.Thisallows theregulatorcircuitstoreachtheir properoperatingpointandavoids excessivevoltageatthehighvoltage terminals. 1-2 INSPECTION Thisinstrumentwasthoroughlytestedand inspectedbeforebeingshippedandisready forusewhenr

14、eceived. Mtertheinstrumentisunpacked,itshould beinspectedfordamagereceivedintransit. Ifanyshippingdamageisfound,followthe procedureoutlinedintheClaimforDamage inShipmentpageatthebackofthisinstruc- tionmanual. 1-1 SECTION II OPERATING INSTRUCTIONS 2-1CONTROLS AND TERMINALS ACPOWER Thistoggleswitchcon

15、trolsthepowersup- pliedtotheinstrumentfromthepowerline. WhentheswitchisintheONpositionthe redindicatorlampabovetheswitchwill glow. LINE4AMP Thefuseholder,locatedonthecontrolpanel, containsa 4amperecartridgefuseforthe protectionofthewholeinstrument.The fusemaybereplacedbyturningthefuse- holdercap,rem

16、ovingtheoldfuse,andin- sertinganewfuse.Replacementfusesfor thisinstrumentmustbeoftheSlo-Blo typeasspecifiedintheReplaceableParts List. -300V1/16AMP Thefuseholder,locatedonthecontrolpanel, containsa1/16amperecartridgefusefor theprotectionofthe-300voltfixedbias supply.Thefusemaybereplacedbyturn- ingth

17、efuseholdercap,removingtheold fuse,andinsertinganewfuse. NOTE Ifthisfuseblows,thepositive high-voltageregulatorcircuit willdroptheHVvoltagelevelto lessthan100volts,thusprotect- ingexternalequipmentorcir- cuitsagainstthepossibilityof damageduetolossofbias.When theopenfuseisreplaced,allcir- cuitsresto

18、retonormal. +HV1/2AMP Thefuseholder,locatedonthecontrolpanel, containsa.5amperecartridgefuseforthe protectionofthehighvoltagedccircuit. Thefusemaybereplacedbyturningthe fuseholdercap,removingtheoldfuse,and insertinganewfuse. 2-1 CAUTION Ifthisfuseblows,immediately turnofftheACPOWERswitch, andthenrep

19、lacethefuse.Con- tinuedoperationoftheinstrument withthe+HV1/2AMPfuseopen willdamagethescreengridsof theseriesregulatortubes(V3, V4,V5,V6). HIGHVOLTAGE Thistoggleswitchturnsthehighvoltage directcurrentoffandon.Theswitchalso controlstheredindicatorlightaboveiton thecontrolpanel.Whentheswitchison, thei

20、ndicatorlampglowsasawarningthat thehighvoltageisturnedon. 6.3VAC,10AMP Thetwofuseholders,locatedonthecontrol panel,eachcontaina 15amperecartridge fuseforprotectionofthe6.3voltACfila- mentsupplycircuit.Eachfusemaybere- placedbyturningitsfuseholdercap,re- movingtheoldfuse,andinsertinganew fuse.Replace

21、mentfusesmustbeofthe Slo-BlotypeasspecifiedintheReplace- ablePartsList. 6.3VAC10AMPCT Thesebindingpostsareterminalsforthe unregulatedACfilamentsupply. 6.3VAC10AMP Thesearetheterminalsforthe6.3volt unregulatedalternatingcurrent. CT Thisbindingpostistheterminalforthe centertapofthesecondarywindingfrom

22、 whichtheunregulatedACistaken. -300V50MA5NIAGND Thesebindingpostsareterminalsforthe biassupplyoutputandchassisground. -300V50MA Outputterminalforthefixed-300Vregu- latedvoltagesupply. 5MA Outputterminalforthevariable(0-150 volt)regulatedbiasvoltagesupply. GND Terminalformakingconnectiontothe chassis

23、.Anyoneoftheoutputterminals maybeconnectedtothechassisbycon- nectiontoterminalGND. COM+HVGND Thesebindingpostsareterminalsforthe highvoltagesupply,commonconductor, andchassisground. +HV Outputterminalfortheregulated0-500 voltvoltagesupply. COM OutputterminalcommontotheHV,5MA (variablebias),and-300V5

24、0MA(fixed bias)circuits GND Terminalformakingconnectiontothe chassis. -BIASCONTROL Thiscontrolvariestheoutputoftheregu- latedbiasvoltagesupplyfrom0to150volts. HVCONTROL Thiscontrolvariestheoutputoftheregu- latedhighvoltagesupplyfrom0to500volts. METERRANGE Thisswitchconnectstheregulatedhigh voltagesu

25、pplycircuittothevoltmeteron eitherthe0-150Vor0-500Vrange:Opera- tionoftheswitchto0-150-BIASconnects thevariablebiassupplycircuittothevolt- meter. 2-2 OPERATION CAUTION Avoidelectricshockbyturningthe highvoltageswitchtotheoffposi- tionbeforemakinganyconnections totheinstrument. 2-2 Theprocedureforope

26、ratingtheModel7l2B PowerSupplyisasfollows: a.Connectthepowercabletoal15Vpower lineandturntheACPOWERswitchto ON. NOTE Thetriple-conductorpowercableis suppliedwiththenewNEMAapprov- edthree-prongplug.Thethirdcon- ductorprovidesachassisground. Anadaptermaybeobtainedtoper- mituseofthisplugwithtwo-conduc-

27、 torreceptacles. b.WiththeHIGHVOLTAGEswitchinthe offposition,connecttheoutputterminals totheload. c.Ifthebiassupplyistobeused,setthe METERRANGEswitchtothe0-150V -BIASpositionandadjustthe-BIASCONTROL forthedesiredvoltage. NOTE Theinternalimpedanceofthevari- ablebiascircuitcanbeashighas 10,000ohms,dep

28、endingontheset- tingof-BIASCONTROL. d.SettheMETERRANGEswitchatthe0- l50Vor500Vposition,andadjustthe HVCONTROLforthedesiredoutputvoltage. e.TurntheHIGHVOLTAGEswitchtoON, checkthebiasvoltage,andreadjust-BIAS CONTROLifnecessary. f.IftheModel7l2Bistobeusedforan applicationwhichrequi.resapowersup- plyofm

29、orethan500volts,upto300volts additionalmaybemadeavailablebyconnect- ingtheloadacross+HVand-300V50MA. Groundmaybeconnectedtoeitherterminal, asdesired. SECTION III CIRCUIT DESCRIPTION -1GENERAL TheModel7lZBPowerSupplyfurnishestwo separateregulatedsupplies:apositivehigh voltageinthe0-500voltrangeandabi

30、as voltage.AblockdiagramoftheModel7lZB isshowninFigure1 Voltagelevelofthehighvoltagesupplyisad- justedbymeansofapanelknob,HVCON- TROL,whichcontrolsthesettingofvariable autotransformerTl.Theautotransformer suppliesprimaryvoltagetothehighvoltage powertransformer,TZ.Thecomparison voltageintheregulatorc

31、ircuitisadjustedby meansofvariableresistorR39whichisme- chanicallycoupledtotheautotransformer shaft.Thisarrangementmaintainstheregu- latorcircuitatitsoptimumoperatingpoint, regardlessofoutputvoltagelevel. Afterthehighvoltagehasbeenrectified(dual diodesVIandVZ)andfiltered,itisapplied toagroupofseries

32、regulatortubes(pentodes V3-V6),totheDCmilliammeter,andthen tothehighvoltageoutputterminal,+HV.The conductionoftheseriesregulatortubesis controlledbyacascadedifferentialamplifier (dualtriodesVIZandV13).Thedifferential amplifiercomparesasampleoftheoutput voltagewiththevoltagedevelopedacross voltageref

33、erencetubeVII;anydifference betweenthesevoltagesisamplifiedandthe conductivityoftheseriesregulatortubesis changedaccordingly. Thefixedbiasvoltage(-300V)supplycon- sistsofaconventionalpowertransformer, full-waverectifier(dualdiodeV7),andcapa- citor-inputfilter.Thevoltageisregulated bymeansofaseriesre

34、gulatortube(pentode VB),whichiscontrolledinturnbyacascade differentialamplifier(dualtriodesV9and VlO).Operationoftheregulatorcircuitis similartothe+HVregulatordescribedabove. Asourceofvariablebiasvoltageisprovided bymeansofavoltagedivider(variablere- sistorR46)whichisconnectedbetweenthe -300V50MAter

35、minalandtheCOMterminal. Thisvoltageisregulatedagainstlinevoltage variationsonly.Sincetheinternalimpedance maybeashighas10,000ohms,depending uponthesettingofresistorR46,thevoltage willdependupontheactualloadcurrentbe- ingdrawn(5maomax.).Thisvoltagecan bemeasuredbyturningtheMETERRANGE switchtothe-150V

36、-BIASposition. -2HIGHVOLTAGE REGULATOR CIRCUIT Theregulatorcircuitissoarrangedthata slightvoltagechangeinthesampledoutput inthepositivedirectionwillresultinarela- tivelylargevoltageswinginthenegativedi- rectiononthegridsoftheseriesregulator tubes,andviceversa. Figure2showsthearrangementofdualtri- od

37、esV13andVIZwhich,connectedincascade, formatwostagedifferentialamplifier.In eachtube,cathodeconnectionsarecommon forthetwosections.Thusanyvariationin platecurrentinonesectionappearsacross thecathoderesistorcommontobothsections, andresultsinadifferencevoltageineachof theoutputcircuits. Inthefirststage

38、,afixedbiassuppliedby voltagereferencetubeVIIisappliedtoone gridofdualtriodeV13.Thebiasontheother gridofV13isaportionofthe+HVvoltage, sampledwithrespecttothe-300voltbiassup-. plythroughavoltagedivider.Anyvariation intheleveloftheoutputvoltageresultsin voltagechangesintheplatecircuitsofboth sectionso

39、fV13,andcorrespondingchanges inthebiasesonthegridsofdualtriodeVIZin thenextstage. Forexample,ifthevoltageofthesampled outputswingsinthepositivedirection,in- creasedcurrentwillflowthroughtheright- handsectionofV13,whichwillraisethecath- odevoltageandlowertheright-handplate (pin1)voltage.Sincethebiaso

40、nthegridin theleft-handsectionofV13remainsfixed, theincreasedcathodevoltagewilldecrease conductionintheleft-handhalfofthetube, whichresultinanincreaseinvoltageonthe left-handplate(pin6). 3-1 SERIES REGULATOR - HIGH VOLTAGE SUPPLY HV CONTROL - !/ -1.-IOUTPUT.-_.-0:+HV CURRENT -+.-.-. r-. VARIABLE - T

41、RANSFORMER DIFFERENTIAL -+-AMPLIFIERf-+-l - COM ( 5MA (- ?O-BIASCONTROL lGND - -300V - SOMA - - 6.3VAC :CT 10AMP - - POWER INPUT 115V 50-1000, VOLTAGE REFERENCE TUBE DIFFERENTIAL -.- AMPLIFIER + -300 SERIES VOLT SUPPLYREGULATOR FILAMENT TRANSFORMER / -OUTPUT VOLTAGE ) ) Figure1.Model7l2BBlockDiagram

42、 3-2 Inthesecondstage,theright-handsectionof dualtriodeVIZactsasacathodefollowerto increasethesignalonthegridoftheleft- handsection.Theplatecircuitintheleft- handsectionsuppliesthebiasforthegrids oftheseriesregulatortubes.Theplatecir- cuitsofthetwosectionsofVIZarecross- coupled.Thisarrangementresult

43、singreat- eramplifiergainandsensitivity. Toensurethattheseriesregulatortubeswill havesufficientconductivitytomaintainregu- lationundertransientconditions,aseparate screenvoltagesupplyfromseleniumrecti- fierSRIisprovidedfortheregulatortubes. Thevoltagedividerinthevoltagecompari- soncircuitprovidessep

44、aratepathstothe signalgridofdualtriodeV13forhigh-fre- quencyandlow-frequencyvoltages,tomake theresponseoftheregulatedsupplyfastat highfrequenciesandyetverystable.Ata- bout1,000cycles,ACcomponentsarecou- pledtothegridviaresistorR3Bandcapaci- torC4.DCcomponentspasstothegrid througharesistornetwork(R3B

45、,R39,R40, R4l) 3-3 3-3BIASSUPPLYCIRCUIT Arrangementandoperationoftheregulated biassupplycircuitissimilartothatofthe platevoltagesupplycircuitexceptthatpri- marycurrenttothebiassupplytransformer, T3,isnotvariable.Thebiassupplyseries regulatortube,VB,iscontrolledbyadiffer- entialamplifier(dualtriodesV

46、lOandV9). Thecomparisonvoltageforthecircuitis furnishedbyvoltagereferencetubeVII,and thesamplevoltageissampledwithrespect toCOMthz:oughavoltagedividerwhichin- cludesvariableresistorRZ4.Thefixedbias voltageisbroughtouttobindingpost-300V 50MAonthecontrolpanel. Avariablebiasvoltageisavailableatbind- in

47、gpost5MA.Thevoltagelevelofthevari- ablebiassupplymaybeadjustedbymeansof the-BIASCONTROLknobonthefrontpanel. Thecontrolvariesthesettingofvariablere- sistorR46inthevoltagedivideracrossthe biassupplyoutputcircuit. 3 R6 R36 R45 M2 R38 R39 R40 R34R35 2 Vl3 R43 R42 !-300VI 50MA Figure2.PartialSchematicofH

48、ighVoltageSupplyRegulatorCircuit 3-4 CAUTION SECTION IV MAINTENANCE Tubes Voltageswhicharedangeroustolife arepresentwithintheinstrument. Disconnectthepowercablefromthe powerlinebeforeremovingthecover orbottomplate. 4-1COVER ANDBOnOMPLATEREMOVAL RackModel Toremovethecover,unscrewthefourscrews whichfa

49、stenthecovertothebackofthein- strument,andslidethecovertowardtherear oftheinstrument.Toremovethebottom plate,unscrewthefourscrewswhichfasten theplatetothebottomoftheinstrument,and liftofftheplate. CabinetModel a.Ontherearoftheinstrument,remove thefourscrewswhichfastentherear covertothechassis,.Removetherearcover. b.Turntheinstrumentonitsback. c.Removethetwo3/16inchAllensetscrews onthebottom,nexttothecontrolpanel. d.Liftthecabinetofftheinstrument. 4-2REPLACEMENTS VariableTransformerBrush Inspectthebrushcontactatperio