Yamaha-K1020-tape-sm 维修电路原理图.pdf

$,tSTEREO CASSETTE DECKK-l 0nI FRONT PANEL;aIJITPORTANT NOTICEThis manual has becn providcd for the use of authorized Yamaha Retailers and their service personnel.It has been assumed that basic servicc proccdures inhcrant to the industry, and more specifically YamahaProducts, are alrcady known and understood by the users, and have thereforc not been rcstatcd.WARNING: Failure to follow appropriate service and safety procedures whcn servicing this productmay result in personal iniury, dcstruction of expcnsivc components and failure of theproduct to perform as specificd. For thesc reasons, we advisc all Yamaha product ownersthat all servicc required should be performed by an authorizcd Yamaha Retailer or thedppointed rer vice reprerentativc.IMPORTANT: The prescntation or salc of this manual to any individual or firm does not constituteauthorization, ccrtification, recognition of any applicable technical capabilitites, orestablish a principle agent relationship of any form.Thc data provided is belicved to be accurate and applicable to the unit/s indicatcd on the covcr. Thercscarch, engineering, and scrvice departments of Yamaha are continually striving to improve Yamahaproducts. Modifications are, therefore, inevitable and changes in specification are subject to change withoutnotice or obliSation to retrofit. Should any discrepancy appcar to exist, please contact the distributorsServicc Division.Static dischargcs can destroy experrsive components. Discharge any static electricity yourbody may have accumulated by grounding yourself to the ground buss in the unit (heavygauge black wires connect to this buss).Turn the unit OFF during disassembly and parts replacement. Recheck all work beforeyou apply power to th unit.IHYAMAIIA .,- !.!.,-! !,ts,+-t- L-rL) AL-t :u Lt,t_t Lt lE :rr:rr_- t-EE-f-ffir-ilILIL-(DS,0 (DilI CONTENTSTOSERVICEPERSONEL .1REARPANELS. .1BLOCKDIAGRAM .2SPEC|F|CAT|ONS. .3INTERNALVIEW. .3DISASSEMBLYPROCEDURES . . 4-6MECHANICALADJUSTMENTS. 7 -9ELECTRICALADJUSTMENTS . .9-11LSI DATA TABLES 12TIMINGCHART .13PRINTED CIRCUIT BOARD (Pattern Side) . . 14 - 17wtRtNG . . . . 18fcBLocK .19-21SCHEMATICDIAGRAM .22,23PARTSLTST. .24-36SINCEI87 YAMAHANIPPON GAKKI CO., LTD. HAMAMATSU, JAPAN2.5k 533 El Printed in Japan. 85 . I_ .1RadioFans.CN 收音机爱 好者资料库2.K-ro2()I TO SERVICE PER,SONNETCntical Components I nformation.Components having special characteristics are marked and must be replaced with parts having specif ications equalto those originally installed.Leakage Current Measurement (For l20V Model Onlv)When service has been completed, it is imperarive ihat yo,verify that all exposed conductive surfaces are properlyinsulated from supply circuits.Meter impedance should be equivalent to 1 5O0 ohm shunreoby 0.1 5r FLeakage current must not exceed 0.5mA.Be sure to test for leakagewith the AC plug in tjoth polaIrres.I REAR PANELSU.S.A. & Canadian modelsGeneral modelBritish & Australian modelsEuropean modelWALLOUTLETT .-.-* e-tt4,7J,r.,r.AlTERa-a$INSULATING TABLE.iltilil| tiltilililrilf il| il0AffiAffIftfffRadioFans.CN 收音机爱 好者资料库El_laxllee II;xd.;uEH./i -s-s:tEtrLl/,a ;tru,;oGYzo2tz=U3AEoasIGFcFItucazzooo=,t|nloPfdlofee?l ,pp;l i=*lFs3-. 6El,I,n:ud-ri5qu!ooUFAYyJ;F- 9e a*.HlVl!-U-o8tsUallnqa- FZolr/UInF lf lzlJ- 6JoJ u6;rJIutz_t oua = , | - oJO a-i&r Jr,. | E=U I FI 1l-tuoloo. Q i f:;N-fiJtqldisKr =l/,-J nl5A 9+-.35 |Xfi Y LEf I*l-l*rl7|nL-,1,Q. IEUJEFlr,=Jd)O- lrJIaK-|o20T SPECIFICATIONSType4-track. 2-channel stereoI nput Sonsitivity I mpedanceLi ne40 mV/30 k-ohmsHeadR & P Heads: Combination, Pure Sendust withtriple-laminated coreErase Heads: lon-plating Ferrite, Double-gapOutput Level/Load I mpedanceLineHead ohonesChannel Separation (31 5O Hz)Cross Talk i125 HzlMotorsCapstan: DC Servo MotorReel: Flat torque DC MotorAssist: DC Motor360 mV/47 k-ohms3.6 mW/8 ohms40 dB60 dBWow & FlutterNo more than +0.06% (W. Peak);No more than 0.03% (W. RMS)Power SuppliosU.S. & Canadian ModelsEuropean ModelBritish & Australian ModelsGeneral Model12OV AC,6OHZ22OV AC, 50HZ24OV AC,5OHZ1 1 0 I 120 I 220 1240V AC. 50/60H2Fast Wind TimeAbout 70 seconds/45 seconds(High Speed winding) (C-6O)Frequency ResponseNormal tape (-2OdB)Chrome tape (-2OdB)Metal tape (-20d8)Power Consumption28 watts20 to 18.O00H2 t 3 dB20 to 20,000H2 + 3 dB20 to 23,000H2 t 3 dBDimensionsWxHxD435 x 134 x 380 mm17I la x 5-1 14 x 15Weight7.6 kg 16 lbs. 12 oz.Signal to Noise RatioDolby oftDolby B onDolby C ondbx onMore than 59 dBMore than 67 dBMore than 75 dBMore than 95 dBSpecifications are subject to change without notice.(u).(c) .U.S.A. modelCanadian modelHarmonic DistortionNormal tapeChrome tapelvletal tapeLess than 0.5%Less than 0.5%Less than 0.8%(A). Australian model(G). European model(B) . . British model(R1. General modelI I NTTNNAL VIEWO PoWER TRANSFoRMERU.S.A. & Canadian models: GA68590European model : GA68600Australian & British models: GA68610General model: G468620) powEn clRcurr BoARD (1) vnrru crRcurr BoARD (1)()dbx Circuit Board Ootby Circuir Boardcnpsreru MoroR(D neel MoroR nssrsr MoroROp-COM lC: LM6402G-494powEa crRculr BoARD3K-ro2()I DISASSEMBLY PR,OCEDURES1. Adjustment of mechanism unit and replacement ofhead parts.a. Remove the cassette lid.b. Remove 2 screws O in f ig. l and remove the blindPlate.c. Remove 4 screws in Fig. 1 and remove the frontpl ate.* In this state, the head can be adjusted and its partscan be replaced.Fis. 1d. Remove 2 screws O in Fig. 2 and replace the record/playback head.e. Remove the screw in f ig. 2 and replace the erasehead.f. Remove the E ring in f ig. 2 and replace the supplyside pinch roller.g. Remove the E ring in f ig. 2 and replace the take-up side pinch roller.h. Bemove the washer O in f ig. 2 and replace the idler. Hsd wiring diagramviewed from theu nderside)Bemoval of mechanism unitRemove 5 screws in f ig. 3 and remove the topcover.Remove the cassette lid.c. Disconnect connectors #1Fis.4.Fis 3through rfi, +7 and #8 in. CONNECTOR WIRINGoA, G, B models.R model.U, C models BL2.d-b.d.RmCassette LidVoltageR. A, G, A mod.l! otrlrr) RE lF6frE;Tfil t, BE - 3121E: G model-RE: A, B modelsFig.2d.I:IiiI;ii!ARemove 4 screws ) in f ig. 5 and pull outmechanism unit gradually to the rear.Replacement of capstan motorRemove the mechanism unit.Remove 4 screws in f lg. 6 and remove the back-plate.O WIRING OF MECHANISM UNITthe 3.a.b.Fig.5r/IJAIIIiji. Srtting flywhsl belt(viryed trom the rsr)Fig.6Sensor Circuit BoardReel Motor - LavelAFc. Remove 3 screwsmolor.) in Fig. 7 and replace the capstanFig.74. Replacement of reel motora. Remove the mechanism unit.b. Remove 2 screws in Fig. 8 and remove the blindPlate.c. Remove the reel base as shown in Fig. 8. Note that coil springs of the supply reel and takeupreel are different.Supply side: SilverTake-up side: Greend. Remove the back plate (Refer to Fig. 6.)e. Remove the washer in f ig. 8 and remove theflywheel (take-up side).K-ro20Remove 2 screws and nuts in Fig. 9 andremove the reel motor installation plate.Remove 2 screws ln fig.9 and replace the reelmotor.Reel Motor lnstallation PlateFig.95. Replacement of assist motora. Remove the top cover.b. Remove the blind plate.c. Remove 2 screws in f ig. 10 and remove the assistmotor installation plate.d. Remove 2 screws in f ig. 10 and replacethe assistmotor.Assist Motorlnstallation PlateAssist MotorFis. l0s.6Capstan MotorPush the reel base to the rear and removethe ring.Fig. IK-ro20I MECHANICAL ADJUSTMENTS1. Before adjustmento Since head magnetization, dust accumulations, etc.are likely to introduce error in the various character-istics, it is very important that the heads are properlydemagnetized and cleaned.2. lnstruments required. Head Gauge (M-300)o Audio frequency oscillator. Oscilloscope. Mirror Cassette MC-109Ca Torque metero Wow/flutter metero D.C.V.M. (DC Voltagemeter). A.C.V.M. (AC Voltagemeter)/r2-r1.tAdlustmntatmTapeTestPointInstrumentrequiredMode%H.l:iH:, lAdiustmenti natine I Remarks1Check clear-ance betweentake-up sidepinch rollerand capstanshaft.PAUSEFig. AMore than O.52Panch RollerTimingBFigI STOP lWith head baseI jpushed up,j icheck timing atI which pinchI lrollers onI isuoolv side andI itake-up side lcontact capstan Take-up side Pinc roller should startI rotating first.Illli timing ot bothlsides is samultane-ous or supply sideprecedes, adj.ustlment rs requrreo.It-Height of re-cord/playbackhad and tapeguideig.oA.C.V.M.Oscilloscopet, ir- t*tt(MC-109C)-Trq*t*(Cassette type)Repeat adj ustmentin steps 3 to 6 andapply screw lockparnt upon comp-letion of adjust-r9!.Adjust by usingspacer as shown inFig. H.f Ot.n t.t Ptorque, read thecenter of deflec-tron.Headgauge L(M 3oo) I I1lHeadgauge I lwithM300(M-3OO) I lblock placedI lverticallY on reI lcord/PlaybackI lhead, adjust soI lthat M 3OOI lgurg and blocki oecomes ParallelI l(Fis. E)-n.asffi(M-300) i iPBSupply side Head gauge shouldoinch rotler I pass through smoothlVheight adiust- lwathout i.ts block con-ing screw (Fig. Jtacting pinch rollerc) lguide. (Fig. F)n.i. rtn aa- Eavback output of Ljusting screw and R is maximum(Fig. C) jand Phase differenceI lshould be minimumI I (Phase difference lessI lthan 60)r lTape should move in1 lthe center of eraselhead smoothlYlCapstan (suppty side)I lshould move smoothlv.rvu,- Fr -T- -ffi?,c,REWtorque, i 35-559/cmtake up torque 1 i FF, REW torqueand back tensi- I more than 7oglcmon torque. Back tension: I Back tenslorl:lAdjustleaf 5-1Og/cmspring (5 steps) iFie. t) I4R eco rdlpl a Vback head tiltangle5SupplV sidepinch rollerh eightFig.F6Azimuth1OkHz,-10d8(MTT-1 14)LINEOUT7Check Posrtion of erasehead and tapemovement.Check each9Check FFand BEW takuP t imsAC-512712,22ac-60I I l Normal; Less than u5I I secondsI I High speed: Less thanI I I sssecondsCheck speed lsmr f xed varr I3OOO +.:Hzwhileplaying ar,leresrstorat J -rcjback 3kHz test the back of the Itape. lg_apstglt Motor. I(Fiq. J)t0Tape speed3kHz,-10dB(MTT-111)LINEOUTWow,/f luttermeter Frequency counterPBWow/ F lutter3ooo +., !uzI Less than O.O5% Check wow/flutter(WRMS) while confirming3kHz frequencywith wow/fluttermeter counter.-1l.IIIIlo?lJli3l ;,TlIclearaoce l6190r.K-ro2()Fig. BFig. ct-rg. EDifferencebeMeen A .nd BLess than l/2*Make sure to reconfirm after sdjustmentAdjust by beoding head basecontscting part of supply sidepinch roller.Confirm clearance and t;ming atteracljustment. There should be a clear-ance between lhe pinch arm andhead base on both supply and t6ke-up srdes.Take-up Side Pinch Roller-aTapeSupply Side Pinch RollerHeight Adjust ScrwCapstanFig. AFig. DErgHead .Hesd F ix ScrewrTilt Angle Adjust Scrw-A: Be sura to tighten the head fixing scrfl securely, Be sureio apply scrw lck painr to each adjusiingscrry after sdjustment.,/a(t)7Head GaugeM.300eyil I .il|ti-It | .il|t Iil t ililt lll L- .t | r-_I_-r -_:-J Il_-Head GaugeM-300Adjust so that the sameclearance is obtained atthe upper and lwor parts.E;* Take-up side Pinch FlollerFig. FFis. GK-ro2() Use spacer to adjust the h8sd heighlFig. HFig. ICapslsn Moto.Fig. JI ELECTRI CAL ADJUSTMENTSO PLAYBACK ADJUSTMENTS* Make sure to use a new tape of I EC standards for a testtaDe.Alignment tapeNormal TDK AC223 or YAMAHA NR 60CrO2 TDK AC512 or YAMAHA CR 60METAL TDK ACl12 or YAMAHA MR 60o Proceed with the playback adjustments after having finished the mechanical adjustments. (dbx circuit I I dbx circuit iI 1 board) 1-_1 I board) I. RECORDING ADJUSTMENT. Proceed with the recording adiustments after having finished the playback adjustments.tuHe8dHei0hrOrivcr/(-F;f *r;,-.;-l-;- -j-,*l1;l*- Tffr# JW;11E.o- r J;iat-r- I D.cr/M frtor l *roiril- o.rfoc -i iDc.offset lrP2B)-E i I I vR102(R) ii-t-lFryb.ki r - itztzc l Lrrveou-f-eivnr-trl uRlon-L) -i 36otls-v -I I | 1stsa, i (Acvort/da I I vR1o4(R) I t-g.o+tdBv)i I I toonwo/m/ I I rvteter) I lF_+ _+ _ _ f_t _ II s i etayuacr rrequency Mrr.3s6u I r-rr.re oui I ; 6nt i t-f-T;*;,*;J i r.oonre conf irmation I 3t80 + 70ps1 i 1 1 lshoutd be wrthin specif i-response conTtrmatton (J tUU + /Ups, 1 i lshould be wtthin speciti-I ,.I,.r;,tuo|, I I i lcationinFieKa ldbx rc 1 Tpl -rp2 D.C.V.M. 1 Srop 1 vRTOt i 15 t 2mV D.C.I I (dbx circuit dbx circuitt-Aai-tfntT , -tTt T.rj:l:jt- ,. . M.u,-nt Jnaitln,tl *;- *.*,-n.n=.;r lL;F;* faoa*. Appry a rkHz sine *;-u*.tLr-r l*aaE rn-*,-i -lMeter OUT signal from LINE lN so iVR5O4 R) I (red should Ir 1(+4.5dBl I rLiNE l-Au;it that LINE OUT voltase rs I ltisft. Ir ltno uott j li-,i fll$,., $J*,i,-iyJrlirtase is I lrisht ifF;k L*f oscillator f,ppty r ri. rinu *u* fvnsor tr-r I ooe ,g-n, -iwrtn nllnsrEn -lMeter signal from LINE lN so 1VR502 (R) i(redl should FADER isdecreased L ll(OdB) 1 that LINE OUT voltage i tliStrt. and R segmentsi is 360mV (-gdBV). L around OdB shouldI 1 fade out almost simul-* Use 360mV (-9dBV) for 0dB as the standard level ofthis unit. )A98ek Teosion (5 iteps)at Playback model(OdB) 1 that LINE OUT voltage I llight. and R segmentsis 360mV -gdBV. around OdB should , I L fade out almost simur- i_l _ taneousty. IAE1,J#F* ,.t iHlT:lI . i - %:1:i: loo,;:Hp Ratins i .*1li-5Lnso+Tnrrraillp;c.v.n,r.- rnrc israseolust* -Fjg: -noiu.trotn,1lation level TP6 LMaximum (VR107) lt-t tO oscitlation Set VRl 19 and 12O all I 1 output isI the way to the teft. I t ;r.OUT ,TAPE (REC at minimum), set lFi102 (R) i 13mV imize bias leak.I I I BIAS ADJUST to maxi- I l, 1 mum and measure bias I i II leak at LINE OUT when I i I- - -t- - - -l 4t i1I tt tilt -l- - tlrililnun3 ,BrAS Leak MErAL ir-rruE n c.v ru. tIFg_ IHL;tflttped -:19119q -!3;,1.r; -lnJr,- *.rn,nillI I I recording and monitoring I IAC-223INPUTLIN E A.C.V.M.lsrcNnr-T(1 kHz,1 0kHz,-20d B lsimultaneouslv TAPEmode) by using a metalthe standard level)3-rRecord the signal andadjust so that the samelevel as the above ilrlevel is obtained.I rRecord and playback al kHz (-20d8) signaland read the level.Record and playback a10kHz (-20dB) signaland adjust so that thesame level as the above:-!, level is obtainedSet METAL (AC-712) andDerform BIAS TEST.Frequencyresponseshould satisfyFig. N.Ilirrili. i i ii.ii r*lguency is used foradiustment. Bias,191:ll may indi-Each adjustment inSteps4and6shouldbe complited. Con-I simultaneously TAPE I II I mode) by using a metal I Ilitape.lirrllltaneilia-n*Jis-iara-firvF-e.cl.rv. inic l,r,swilrglaiio s -ft*iri lr_jlto.sae - -rh;r.I Levet ilNpuT OUT TAPE 1 the midpoint. lVR1t2 (R) i lthis unir(Through) SIGNAL _-NR-+ ,zApplyalkHzsinewavel (equivat,i L ,(lkHz, iLtNE tnudio oFF I sisnal from LINE lN so I i vn). ttt i 1-20d8) jlN ifrequency I I that LINE OUT voltage I L used, stiri I I j osilaror i I is 36mV (-29dBV). I lin revet r* r-l) 4 Becording tAC-712 ILINE A.C.V.M. REC 1,r,SetVR119and 120as lVR11l L) 10.5d8 Thereferencetapeof Level INPUT OUT TAPE the midpoint. lVR112 (R) this unit is AC-720(Throush) 99.ryAL - -ryl_* ,zApply-alkHzsine-waveI (equivalenttoTDK. Iilii(equivalent to TDK- MA). lf other tape is jused, slight difference jin level results. II 1(Through) TSIGNALT_ -L_lNR-+ jZAnOlvalkHzsinewave | (equivalentt,i L ,(lkHz, iL|NE tnudio oFF I sisnal f rom LINE lN so I i MA). lf otheI i 1-20d8) jlN ifrequency I I that