Ampex-400-tape-adj 电路图 维修手册.pdf

《Ampex-400-tape-adj 电路图 维修手册.pdf》由会员分享，可在线阅读，更多相关《Ampex-400-tape-adj 电路图 维修手册.pdf（15页珍藏版）》请在收音机爱好者资料库上搜索。

1、ff1 EWflELLXAND lfl ADZW:nTMJRTLL I *flnr! RadioFans.CN 收音机爱 好者资料库 AMPEXMODEL400 MECHANICALADJUSTMENTMANUAL TableofContents Pages SECTIONIGENERAL1-2 SECTIONIIOPERATIONALIRREGULARITIESAND THEIRCORRECTION1-3 SECTIONIIIADJUSTMENTS A.BRAKELEVERPIVOTS1 B.BRAKERELEASEARMRESETSTOP1 C.TRIPLEVERSTOP 1 D.FAST

2、FORWARDANDREWINDHOLDBACK1 E,BRAKES 1 F.MASTERSWITCHADJUSTMENT2 G.PLAYENGAGEADJUSTMENT 2 H.TURNTABLEREVERSINGSWITCH2 I.TURNTABLEMOTORCENTERING J.POWERBOOSTERSWITCHADJUSTMENT K.TAKEUPTENSIONARMTENSION 3 L.PLAY RESISTORSWITCH,RECORDINTER LOCKSWITCH ANDPLAYHOLDBACK ADJUSTMENT M,PLAYTAKEUP ADJUSTMENT N.R

3、EELIDLERHEIGHT 4 0,TURNTABLEHEIGHT P.REELSIZESWITCHADJUSTMENT4 Q.CAPSTANIDLERHEIGHT 5 R.CAPSTANTAPEGUIDEHEIGHTS RadioFans.CN 收音机爱 好者资料库 AMPEXMODEL400MAGNETICTAPERECORDER MECHANICALADJUSTMENTMANUAL SECTIONI-GENERAL EachModel400recorderhasbeenverycarefullyadjustedbefore leavingthefactory.Undernormalco

4、nditions,theseadjustmentsarequite stableandshouldnotbealtered.However,ifthemachineshouldgetout ofadjustmentthroughunusuallyroughhandlingoraccident,it mayrequire attention.Acompletedescriptionofalladjustmentsis containedinthis manual. DESCRIPTIONOFOPERATION TheModel400machineusesamechanicallinkagetoc

5、ontrolits variousfunctions.Twomotorsareused,oneforthecapstan drive,the otherfortakeupandrewindoftapeontheturntables.Thelatteroneis engagedwiththeproperturntablebyamechanicallinkageanddrivesit througharubbertireonthemotorpulley.Propertapetensionismain tainedbyafrictionholdback deviceusingfeltpads.Bra

6、kingtoallow rapidstoppingoftapemotionisperformedbyanadditionalsetoffelt- linedmechanicalbrakes. Themodeselectorswitch,togetherwiththeFlaybutton,serve tocontroltapemotioninthemachine.Theformerpositionsthemode changecamintoeither Forward,Rewind,orOffpositions.Settingthis caminto theForwardpositionperf

7、ormsthe followingfunctionsdirections ofmovementarethoseobservedwhenviewingbottomsideoftopplate. 1.BellcrankFig.2-5isrotatedcounterclockwise,moving turntablemotorlinkFig.2_6toleftandtherebycausingmotorpulley toengagetakeupturntable.Simultaneously,rotationofbellcrank. shaft positions turntablereversin

8、gswitchFig.2-3,connectingmotor windingssothat rotationindesireddirectionisproduced. , 2.CamfollowerFig.1-2is movedtoleft,causingcamfol l4owerleverFig.1-3torotateslightlyin aclockwisedirectionabout itspivotFig.l-6A.This motionisimpartedtothebrakerelease armthrougb itspivotFig.1-7Acausingthisparttomov

9、e tothe right.Iftheakeuptensionarmisinoperating positioneitherby tapebeingpraperLthreadedorbybeingheldoverinsomeother manneragainstspringtension,thetripleverFig.1-5willcatch thetriggeredofthebrakereleasearmFig.1-7andtherebycae positiontobeimpartedthroughthebrakereleaserodstothe l-lO.1-i5.Acol1arater

10、switchactuator,Fig.1-17onte RadioFans.CN 收音机爱 好者资料库 brake rodFig.1-11alsowilloperatethemasterswitchFig.1-19, ener gizingtheturntablemotor,Fast Forwardoperationwillthenoccur.If the takeuptensionarmisnotinoperating position,thebrakerelease arm willrotatecounterclockwiseaboutitspivot.Nomotion willbeimp

11、arted tothebrakerods,brakeswillnotrelease,andmaster switchwillnotclose. Inaddition,themodeselectorwillnotlatchinan operating position Ifthemodeselectorcam isplacedinRewindposition,the motion obe11crankandturntablereversingswitchwillbein aclockwise direc tion.Themotorwillrotateinoppositedirectiontoth

12、atdescribed above andwillbeengaged totherewindturntable.Theactionofbrakelinkage willbethesameasforForwardoperation. ShouldthePlaybuttonbedepressedpriortoplacingmodechange caminForwardposition,anadditionalfunctionoccurs.The playengage dogFig.2-2willcatchtheendoftheplayengageleverFig.2-4causing tttoro

13、tatein acounterclockwisedirection.This motioninturnwillbe impartedtotheplayengagetierodFig.2-22,movingittotheleft.Since itisattachedtothecapstan idleradjustmentarmFig.2-21,theidler assemblywillrotatebringingthe id.leragainstthecapstan.Inaddition, apinaffixednearthecenteroftheplayengagetierodwilloper

14、atethe playholdbackactuatorFig.2-12,thusincreasingtheholdback effectto maintainpropertapetension.Simultaneously,movementoftheplayhold- backactuatorpositionstherecordinterlockswitch Fig.2-13,andthe playresistorswitchFig.2-10.TheformerinterlockstheRecordbutton ontheelectronicsunit,whilethelatterreduce

15、svoltageontheturntable motorandconsequentlyreducesitstorquetotheamountneededfor proper tapetensioninthePlaymode. Othercontrolsprovidedarethepowerswitch,whichturnsonthe electronicunitsandenergizesthecapstandrive motor,thereelsizeswitch thisunitisaswitchinnameonly;itservesasamechanicallinkagetocon tro

16、lpressureonplayholdback,andtape speed switchwhichcontrolspeed ofthedrive motorbyvaryingconnectionofitswindings. SERVICING: beforeproceedingwithadjustments,thetapetransportmechanism andelectronicsshouldberemovedfromthecabinetandthetapetransport mechanismshouldbeplacedupsidedowninthecabinetwithitsfron

17、ttoward thefrontofthecabinet.Mostoftheadjustmentscanbemadewiththemachine inthisposition. Therecorderwasdesignedforuseeitherinthehorizontalposition or forrackmounting.Theonlyadjustmentaffectedisthe takeuptension aimtension.Seetakeuptensionarmtension adjustment. AMPEXMODEL400 MECHANICALADJUSTMENTMANUA

18、L SECTIONII OPERATIONALIRREGULARITIESANDTHEIRCORRECTION SnappingthemodeselectorintoForwardpositionwithPlaybutton depressedmaycausethemachinetotripoff. Ifthemachinetripsoffwithnormaloperationofthemodeselector, checkthefollowing: 1.Playengageandmasterswitchadjustments.SeeSectionIII 2.Take-uptensionarm

19、tension.Itmaybetoohigh. 3.Power bcxt switchadjustment. 4.Possiblefailureofmasterswitchorturntablereversing switch. WhenstartinginPlaymode,if excessiveslackdevelopsintapebe tweencapstanandholdbackreeltherebycausingtapetotrackoutofthe capstanengagementandpossiblybreak,thecauseisinsufficientplayhold ba

20、ck. Checkthefollowing: 1.Largereelonpayoutturntablewithreelsizeswitchin smallreelposition. 2.Playholdbackadjustment. Iftakeuptensionarmcontinuestooscillateaftermachineisstarte. inPlaymode,checkthefollowing: 1.Fastforwardaridr.windholdbackadjustment. 2.Takeuptensionrnfor excessivetension. Ifmachinefa

21、ilstotripoffwhen taperunsout orbreaks,checkthe following: 1.Takeuptensionarmtensionwillbetoolow. 2Takeuptensionarmshaftmaybebindingduetogummycondition Ifso,remove,clean,andreplace.Lubricatewithafewdrops oflightoil. Iftapeconsistentlyscrapestheflangesofeither,reel,check tiri following tee1forbentflan

22、ges 2.Differentrollsoftape.Sometapemayhave internalstrains orbeimproperlyslit,causingittowindimproperly. 3.Turntableheight. Iftapedoesnottrackproperlyinreelidlergroove,checkreelidler height.Tape shouldnotbearheavilyoneitheredgeofguidegroove. IfthemachinefailstogointoPlaymodewhenproperlyoperated,but

23、goesinsteadintoFastForward,thecauseisprobablya gummyconditionbe tweenthePlayengagedogandthemodechangecam.Removethemodechange camandwashthestickypartswithsolvent.Placeadroportwooflightoil onthedogpivotwhenreplacing. Ifmachinefailstooperatewhenmodeselectoristurnedtoanopera tingpositionandwhenmodeselec

24、torreturnstooffwhenreleased,checkthe following: 1.Triplever.If gummy,remove,clean,andreplace.Besure thatspringisattached. 2.Triplevers.topadjustment. Ifmachinefailstooperatewhenmodeselectoristurnedtoanopera tingpositionandmodeseiectorremainsinthatposition,checkthefollowing: 1.Masterswitchanditsadjus

25、tment. 2,Turntablereversingswitchanditsadjustment. 3.Topplatefuse. 4.Powerswitchandtopplate wiring. Ifbrakingistoosevereorirregularthecauseisprobablyaforeign depositonthebrakedrums.Cleandrumswithcarbontetrachlorid.orother solvent.Thefeltliningsshould functionproperlyafterthedrumshave been cleaned.Ho

26、wever,iftheyhaveinsomewaypickedupoiltheyshouldbe.re placed. Iftherubbertiredturntable drivewheelslipsonthebrakedrumin anymode,thesituationshouldbecorrectdimmediatelyastl!rubbertire willbeinjured,andrubberwillbedepositedonthbrakedi1rnscausing brakeandholdbackproblems. Checkthefollowing; 1,Presenceofo

27、ilonbrakedrumsor.tire. 2.Turntablemotorcenteringifslippageoccursinonlyone direction 3.Masterswitchadjustment. Iftapetendstowanderupordownfromengementbetweencapstan andcapstanidler,checkthefollowing 1.Capstanidlerheight. 2.Capstantapeguideheight. 3.Playholdbacktensioneithertoogreatortoolight. 4.Playr

28、esistorswitchnotcuttingin. 5.Powerboostswitchadjustment. Withthemachineinplaymodethereshouldbeanextrasurgeof powerasthe takeuptensionarmisforciblymovedinagainstthetape.If thissurgedoesnotoccurbeforethemachineshutsoffduetothetakeup tensionarmbeingpushedtowardtherestoroffposition,thenthemachine cannot

29、operatesatisfactorily.Checktheplayresistorswitchand power boostswitchforproperadjustmentandifnecessarymakefurthercheckto determinethattheswitchesarefunctioning. MODEL400MECHANICALADJUSTMENTMANUAL SECTIONIII A.BRAKELEVERPIVOTS -FIG,1-20 Ifforanyreasonthebrakeleversareremoved,replaceinsame. positionfr

30、omwhichtheywereremoved.Tightenlocknut,Fig.1-20, untilit bottomsonthebrakelever,thenbackoffapproximately1/4 turn.Allownodragonthebrakeleveratthis point. B.BRAKERELEASEARMRESETSTOP-FIG1-8 1.Placemodeselectorinoffposition. 2.Loosensecuringscrew,Fig.1-8Aandsetstop sothatthetrigger ingendof thebrakerelea

31、searm9Fig.1-7,isapproximately1/16 fromthebrakereleasearm triggerendstop,Fig.1-7B. 3.Tightensecuringscrewusingcaretoavoidmovingstop asscrewis tightened. C.TRIPLEVER STOP-FIG,1-4 1.Fastentakeuptensionarminoperatin,positionwithScotch tape. 2.Loosenstopsecuringscrew,Fig.1-4A,andturnstoptoaposition thatw

32、illallow3/64to1/16contactbetweenthetriggerendofthe brakereleaselever,Fig.1-7,andthetriplever,Fig.1-5,asth modeselectoristurnedfromofftowardeitheroperatingposit. 3.Tightenstopsecuring screw. D.FASTFORWARDANDREWIND HOLDBACK -FIG.2-8and24 1.Removebrakedrums.Notepositionsothateach drummas placedonthesha

33、ftfromwhichitwasremoved. 2.Therewindandfastforwardholdbackarms,Fig.2-8and24. have arestposition2-3/4inchesfromtheturntableshaft,Bend.a. apointclosetotheirmountingstocorrectanymisadjustinent.Be surethat linings contactdrumsevenlyanddonotbearheavilyor heelortoeoflining. E.BRAKES-FIG.1-10and15 1.Swingt

34、akeuptensionarmontopplatetooperating positionandfasten ittherewithScotch tape. . . 2.Turnmodeselectortoeitheroperatingposition. . 3.Loosensetscrewonrewind brakeadjustmentcollar,Fig.1-9,ad adjustbrakeshoetohaveminimumclearancefrom drum,Tighten setscrew.Checktodeterminebrakedoesnot,drag. 4Loosensetscr

35、ewontakeupbrakeadjustu,ncllarandadjust.brake shoetoclearbrakedrumby1/32Tietacrew F.MASTERSWITCHADJUSTMENT -FIG.1-19 1.Fastentakeuptensionarminoperating positionwithScotchtape. 2.WiththePlaybuttondepressed,movemodeselectorinforward directionuntilmasterswitch timinblineoncamfollowerarm lines upwiththe

36、edgeofthemodechangecamas showninFig.1-21. 3.Setmasterswitchtoclickatthispointbyadjustingpositionofthe masterswitchactuator,Fig.1-17.Fineadjustmentsmaybemade bybending themasterswitchtongue,Fig. 1-18, slightly. 4.Tightensetscrewinthemasterswitchactuatorandrechecktosee thatthemasterswitchclicksjustast

37、heedgeofthecamlinesup withthemasterswitch timingline.Alwaysperformthischeckin playmode, G,PLAYENGAGEADJUSTMENT Alwayscheckmasterswitchadjustmentseeprecedingparagraph beforemakingthisadjustment. 1.Fastentakeuptensionarminoperating positionwithScotchtape. 2.Adjustcapstan idleradjustmentclamp screw,Fig

38、.2-19,togive mediumdragbetweencapstan idleradjustmentarm,Fig.2-21, andcapstan idler armshaft, 3,DepressPlaybuttonandmovemodeselectorinforwarddirection untilmasterswitchclicks.Shiftthecapstanidlerarm,Fig.2-20, withrespecttothecapstan idleradjustmentarm,Fig.2-21,so thatthecapstan idlerFig.2-17isabout1

39、/64 fromthecapstan, Fig2-16,asthemasterswitchclicks. 4.Securelytightencapstan idleradjustmentarmclamp screw,Fig.2-19. 5.RecheckbydepressingPlaybuttonandmovingmodeselectorin forwarddirection.ThemasterswitchshouldclIckasthecapstan idlerreachesapointabout 1/64fromthecapstan.Donotallow thecapstan idlert

40、otouchthecapstanbeforethemasterswitchclicks H.TURNTABLEREVERSINGSWITCH-FIG.2-3 1.Loosen clampboltonbellcrank,Fig,2-5A; 2.WithmodeselectorinOffposition,rotateswitch switchrotorbladesarecenteredintheswitch, 3.Tightenbellcrankclampbolt. shiftuntilthe Ifthemodeselectordoesnotsecurelylockinbothpositionsw

41、hen the takeuptensionarmisheldinoperatingposition,itis probablybe causeofmisadjustmentofthisswitchThestopontheswitch iscausing aprematurestoppageofthecamReadjustslightlytocorrectthiscodi. tion. I.TURNTABLEMOTORCENTERING-FIG, 2 I.Removeturntablemotolink,Fig.26,mbellcrank. Fig.2-5. 2.Holdthe.turntable

42、motorcenteredaccuratelybetweenthebrake drums.Asimplecenteringjibcouldconsistoftwopiecesof1/16 thickmetalinsertedbetweenbrake drumsandturntablemotortire. 3Revolvetheturntable motor link,Fig2-6,untilitlinesupwiththe outside holeinthebellcrank,Fig2-5 4.Insertturntablemotorlinkfromcastingsideandinstalln

43、ewretain ingring J.POWERBOOSTERSWITCHADJUSTMENT-IG.1-16 1.Movethetakeutensionarmfromitsrestoroffpositiontoward thereelidler,Thepowerboostmicroswitchshould clickoropen asthearmguidepassesthrougha linedrawnbetweenthecenterof thereelidlerandthecenterofthe takeuptensionarm bearing. 2.Ifnecessary,adjustb

44、ybending themicroswitcharmslightly. K.TAKEUPTENSIONARMTENSION -FIG.1 Theamountoftensiongiventothetakeuptensionarmisimportant. Anamountjustsufficienttotripthemechanismshouldbemaintained. Ifexcessiveitwillcausethemachinetoshutoffduringrewindorfast forwardandcausestartingdifficulties.Forrackmounting,ad

45、ditional tensionhastobeprovidedtocompensatefortheweightofthetensionarm Adjustmentisaccomplishedbylooseningthelocknutatthecamfol lowingarmpivot,Fig. 1-6A,and movingtakeuptensionarmadjustment lug,Fig.1-6,toobtaincorrecttension.Forrackmountingitmaybe necessarytoshortenspringtosecuresufficienttension. L

46、,PLAYRESISTORSWITCH,RECORDINTERLOCKSWITCH ANDPLAY HOLDBACKADJUSTMENT 1.Faste.ntakeuptensionarminoperating positionwithScotchtape. 2.Connectohmmeteracrosstheoutsideterminalsofplayiesistr, Fig.2-15,usingalowresistancerange,todetermineexacttime ofplayresistorswitch action. 3.Playholdbackactuator,Fig.2-

47、12,shouldbeinapproximately normal positiononshaft. . 4,Loosenclampscrewonswitchactuator,Fig.2-25,butmaintain slightdrag. 5Moveswitchactuator,Fig2-25,ontheswitchshaftothatthere sistorcutsinafterthemasterswitchclickasthemodeselector is movedintheforwarddirectionwiththeplaybuttondepressed Resistorshoul

48、dcutinwhenpositionofthemodeche.ngecamand camfollowerareas showninFig 3 6WithmachineinPlaymode,readjustplayholdbackactuatoras showninFig2-12untilitpressestheentire surfaceoftheplay hdbackfeltevenlyontheholdbackbrakdrumPlayhod,bak shouldbe4oz,measuredwithrecorderinPlaymodeandfrom N. A. B.hub,Reel size

49、switchshouldbeinlargereelposition. Securelytightenclampscrewwhenadjustmentiscompleted. 7.Recheckplayresistorandrecordswitch,Besuretheplayresistor switchiscorrectlyadjustedasinParagraph5,above,Recordinter lockswitchadjustmentisalsoaccomplishedbythisprocedure. M.PLAYTAKEUPADJUSTMENT Theslideontheplayresistor,Fig.2-15,adjuststheplaytakeup. Movingtheslidetowardthetopplateincreasesthetakeup. Tocheckforpropertension: 1.Fastentakeuptensionarminoperating positionwithScotchtape and withtransportmechanisminnormal positionandpowerconnected. 2.Attachashortpieceofstringabout30tothetakeup