Pioneer-SX990-rec-sm 维修电路原理图.pdf

PIONEEFIvJSOLID STATEAM/FM STEREO RECEIVERModels)Ges|oCAUTIONBefore connecting the line cord to the wall socket, carefully read andfollow the instructions described below, to assure the safety of yourunit. This rsceiver is set for 24OV operation when shipped. lf this unitis usd in a different linevoltage arsa, read and follow LINEVoLTAGE SELECTION AND FUSE on page 1. Be sure that thelin voltage sstting on your unit agrees with tho line voltags inyour area and that the fuse installed in your unit is a proper one.INSTALLATION, OPERATING AND SERVICE MANUALIncluding PARTS LIST, CIRCUIT DIAGRAMS, TROUBLESHOOTING AND MOUNTING TEMPLATE.(FVW)PIONEER ELf, CTRtrNIE EtrRPtrRATItrilRadioFans.CN 收音机爱 好者资料库IrJIONEEFIFEATURESHIGH.PERFORMANCE FM TUNERAn FET field-effect transistor) is used in th radiofrequency amplifier to attain a highsensitivhy and selectivity. Funher, four lcs (integrated circuits) are usd for thintermediate frequency amplifier to eliminate interference and noise.BUILT.IN EXCELLENT FM MPX CIRCUITThis srwitching cirdit having excllent separation and frequency response is built in forreproduction of rea lity music.BUILT-IN HIGHLY-SENSITIVE FERRITE ANTENNA FORRADIO RECEPTIONThe ferrite antenna provides high-sensitivity reception of AM broadcast programs. SPECIAL CIRCUITRY FOR VERSATILITYThe high output given by strictly selected transistors, two seG of loudspeakor terminalsand phono terminals, and the provision for using a microphone make Model SX-990suitable for the professional use a well 6 the family use.A VARIETY OF ACCESSORIESAccessories include the program lamps that indicate the program being played, thetuning meters vertically arranged for facilitating selection of an FM broadcast program,the loudspeaker selector switct, tape monitor switch, etc., all for enjoyable use of Modelsx-990.ELEGANTLY DESIGNED FRONT PANELNarvly designed knob6 are uniquely arrangd on the silver tone panel.LINE VOLTAGE SELECTION AND FUSSWITCHING LINE VOLTAGE SETTING AND FUSEIn order to remove the fuse, tum the fuse cap locatedon the line voltage selector switch in the directionindicated by an arJow. Then remove the fuse plugfrom the unit. Put the fuse plug back so that theproper line voltage marking can be seen through thecut in the edge of the plug.Whenever the set position of the selector s itch ischanged, check the rating of the fuse. A l-ampere fuseis to be used for either 220V or 24OV operation and2-ampere fuse for any of 110V, 117V, or 130Voperation. lf the rating of the fuse is proper, installthe fuse in the fuse caD.REPLACING OF FUSEWhen the fuse is blown, remove the fuse cap andreplace the fus with a nevv one.Take off the fuse cap by turning it with a coin,etc. in the direction indicated by the arrow mark,AIIIwvcottFUSE PLUGFis. 1RadioFans.CN 收音机爱 好者资料库REAR CONNECTIONSTURNTABLE(MM) CARTRIDGETAPE PLAYERCRYSTAL /CERAMICTAPERECORD PLAYER GNDI TERMINALRECORDINGTAPETAPE REC / P.B.CONNECTOR(DIN TYPE)REC/P. S.TAPEMONITORfo)ro)lTAPEESPEAKER OUTPUTFTERMINALSl(4n-l6a) gCENTERCHANNEL220V2At 3 0 vI tovINOTE : tf the(DlNtype) isCONNECTOR ,and MONITORA-SPEAKER SYSTEMB-SPEAKER SYSTEMNOTE: l. Whn only on st of sPaker systm is connectedto th Sx-99O. The speskr imPedance mav be 4to 16 ohms.2. Do not short the SPEAKER TERMINALS.ALL TERMINALS *9*O !T! LJJL4EFMAGNETICARE INTERNALLYPHONO I PHONO2wrREo AS FOLLoWS: | ry q! ryx;l*;:i:11$ E ELINE VOLTAGISELECTOR AILEFT CHANNELCHANNELRIGHTCHANNELLINE CORDFM ANTENNAlI the indoor antennajs not adequate forreception of FM Prog-rams. seParatly esta-blish an antenna in theoutside ol th house forreceiving FM sig alsSTEREO SYSTEMThe SX-990 is a generafpurpce stereo amplifier.Connect to it the loudspeoker systems (two or four),turntablo, tape recorder, etc., which are separately6vailable.Fig. 3INSTALLATIONFor installation of the stereo system, select a placerneeting the follo,ving:. Well ventilated. and free from moisture and dust. Unex posed to direct slnlighta Far from heat radiators (space heaters. etc). Stable without incurring vibrationsLISTENING ROOM. When the stereo system is installed, listen to musicaccording to the connection and operation in-structions descriH below. The reproduced sound isvery diffurent dependingon the size of the room, the furniture anangementin the room, and the materials of walls,floor andceiling.Generally, the reproducd sound fills the room ifthe room has a low ceiling and hard floor, or theroom has a small length and a hard wall opposingloudspeakers. This undesirable acoustlg conditioncan be much alleviatd by laying a carpet on thefloor for the former room and by covering thewall with a thick olrtain for the latter room. lt isalso an effective solution to dlange the arrangement of fumitur6 for irregular reflection of ttleloudspeaker sound.ecordlplayback connectorrrovided on your tapeAPE REC / P,B.erDinals to the rsceiverRECOROER)FM ANTENNATERMINALS230 VA(TAPEFis.2IPIONEETTCONTROLS AND SWITCHES ON THE FRONT PANELPROGRAM3 rruotcnroR LAMPSt61514l3l.SPEAKERS SWITCHA combination of the Dower on/off switch and thloudspeaker system selector switch.NNssK:w slf o,N N KK+ sexn,s-orr_lr+e_:;1ssGmffKr:Fig.4POWER OFF:.The equipment is deenergized.The power supplied from theS1I/ITCHED AC outlet (36) is discon-tinued simultaneously.A: .-.-.-. Sound is reproduced from the loud-speaker system connected to theSPEAKER OUTPUT A terminals (31and 321.SPKR OFF: . Loudspeakers stop sounding.This position is selected when using astereo headphone.B: .-.-.The loudspeaker system connectd tothe SPEAKER OUTPUT B terminals(33 and 34) is put in operation.A + B: . .-.The loudspeaker systems connected toSPEAKER OUTPUT A and B termi-nals are put in operation,FM _E6 e0 s2 s4 .g!jgj0g_-10:_I0j_!0j_!0!_.MHzia-i6t-xrokrzSPEAKEFISFi$ 52. TUNING METERSWhen tuning the receiver to an AM broadc6tirEstation, adjust the TUNING knob (4) so the pointerof the lower one of the meters deflects largelyrightward.When tuning the receiver to an FM broadcastingstation, adiust the TUNING knob so the pointer ofthe lower meter deflects largely rightward and, inaddition, the pointer of the upper meter is at thecenter,Tuning to AM Rdio StationFis.63. FM STEREO INDICATORThis lamp is lit during reception of an FM stereoprogram.4. TUNING KNOBThe knob for tuning the receiver to an AM or FMbroadcasting sttion. Adiust the knob for the besttuning while obsrving the tuning meters (2).5. SELECTOR SWITCHThe s,witch for selecting the program source.AM: . . For reception of an AM program.FM MONO: .,. For recption of an FM monauralprogram,FM AUTO: . For automatically selectiv receptionof stereo or monaural FM Program.PHONO 1. For playing a disk record by using theturnbble connected to the PHONO 1terminals (17),PHONO 2/MlC: For playing a disk record by using theturntable connected to the PHONO 2terminals (18) or for using a micpphone by inserting its cord plug intothe MIC iack (16). (When the microphone is connected to the iack, theturntable connected to the PHONO 2terminals cannot be used.)AUX: .-. For using the cartridge tape player,reproducing the TV audio output, oroperating other equipment connectdto the AUX terminals (20).When the SELECTOR sl,vitch is operated. theprogram indicator lamp corresponding to the select-ed source ligh.6. PHONES JACKWhen using a stereo headphone, insert its plug intothis iack. For the headphone to be used with ModelSX-990, PIONEERs Model SE-20, SE-30 or SE-50 isrecommended.When a longer cord is required for the stereoheadphone. use PIONEERs Model JB-23 extensioncord separately available.When desiring to connect two stereo headphonetuse PIONEERs Model JB-22 Y cord separatelyavailable.BASS CONTROLWhen this knob is turned clockwise, bass is boosted;when tumed counterclockwise. attenuated. Whh theknob set to the center, the frequency response curveis flat. The center and outer knob6 of this doubleknob are friction-coupled with each other. and thetone of both left and right channels can be adjustedsimultaneously by tuming either knob. The centerknob is for the left channel. and the outer knob isfor the right channel. When adjusting the tone ofonlv one of the channels, turn the knob for thatchannel while holding the other knob by the otherhand.RIGHT CHANNEL(cH .R)Tuning to FM Radio Stationtw-t*7.LEFT CHANNEL(cH .L)Fis.7OIv8. TREBLE CONTROLUse of this knob is similar to that of the BASScontrol knob (7).9, FILTER SWITCHESLOW: A svtitch for suppressing low-frequencynoise or hum.HIGH: A su?itch for zuppressing high-frequencynoise.These s,witches are of the pushbutton type. Whenthe button is pressed once, the switch tums on. andwhen pressed once again, it turns off,10. BALANCE CONTROLThis knob is used for adjusting the stereophonicbalance. When the volume of the right channelloudspeaker is smaller, turn the knob clockwisetoward RIGHT; when left channel volume is smaller,counterclockwise toward LEFTBALANCEwhn the volume *.)jlt- when the volume oteft channet f N right chsnneltoudspeak6r it lk-+:) loudsPeaker issmattr VrZ smallerLEFT- FTIGHTFig.811. VOLUME CONTROLThe volume increases when the knob is turnedclockwise,12, 13 and 14 are pushbutton switches. Switchesturn on when the pushbuttons are depressed once;turn off when depressed again.12. LOUDNESS SWITCHWith this switch turned on when the sound volumeis low, insufficiencies of bass and treble are com-pensatd for. When the sound volume is high, it isrecommendd to keep this s,witch turned off.13. MUTING SWITCHTurning on this switch, the noise generated whentuning the receiver to an FM station can beeliminated. lf l4odel SX-990 is used where the FMfield strength is low, keep this str/itch turned offsince the program sound is also suppressed with theswitch tumed dn.14. TAPE MONITOR SWITCHTurn on this switch for listening to or monitoringonly the signal reproducd by a tape deck (or taperecorder). When not using the tape deck (or taperecorder). keep this switch turned off. Otherwise,loudsoeaken will not sound.15. MODE SWITCHFunctions as follows:REV. Stereo, with lefi and right channelinput signals exchanged for eachother.STEREO . Normal stereoL.- Monaural play with only the leftchannel input signal fed to bothchannel loudsDeakers.R. Monaural play with only the rightchannel input signal fed to bothchannel loudsPeakers.L + R . Monaural play with both leftand rightchannel input signals mixed togetherand reoroduced from both channellou&Deakers.If- R* -_ll-.-T-_.-/-_-r1., -H-f *T:llt *;-_- LEFrv -t- rlr-r -.tI D U T I I I O U T P U TL-RGHro I L.-.-r .-;-_-l-LEFro-t- !LE;r-.1t:1., -+-t-F ,.?i-. Fis.916. MIC MICROPHONE JACKWhen a microphone is connecGd to this iack, thesignal fed from the turntable connected to thePHONO 2 terminals (18) on the rear panel isd iscon nected,ITJTONEEIITERMINALS AND CONNECTORS ON THE REAR PANEL:17 18 t9 20 2122 232526 2735 36 3728 29 30 31 32 33 34The upper ones of the terminals 17, jA,20,21,22,28 and 29 are for the left channel respectively; thelower onet for the right channel.17. PHONO 1 TERMINALSMAG: .,. Connect here a turntable equippedwith a moving magent cartridge.CER: .,.,. Connect here a turntable equippedwith a ceramic or crystal cartridge.NOTE: Two turntable cannot be connectedto the MAG and CER terminalssimultaneously.18. PHONO 2 MAG TERMINALSConnect here a turntable equipped with a movingmagnet cartridge.3BFis. 1019. GND (GROUND) TERMINAL 1lf the turntable or other equipment used with/odel SX-990 is provided with a ground wire,connect the wire to this terminal.20. AUX. (AUXILIARY) INPUT TERMINALSConnect here the output of a cartridge tape player.21. TAPE MON TERMINALS (TAPE PLAY.BACK INPUTS)Connect the iine output or monitor output of tapedeck (or tape recorder) to these termanals.22. T APE REC TERMINALS (TAPE RECORD-ING OUTPUTS)Connect the line input of a tape deck (or taperecorder). Signal is always supplied to these termi-nals while SX-990 is working; however, the signalOIwcannot be controlled with the VOLUME (11),BALANCE (10), TREBLE (8) or BASS (7) controlon the fmnt Danel.23. TAPE RECiPB CONNECTOR(DI N TYPE)lf the tape deck (or tape recorder) to be used withModet SX-990 is provided with a record/playbackconnector of the DIN type, the tape deck (or taperecorder) can be connected to Model SX-990 for bothrecording and playback (and monitor) by simplyconnecting the DIN cable.When this cable is used, connections to terminals(21t. and l22l are unnecessary.The detail of connection is shown on page lO.Connection of tape deck (or tape recorder),.24. AM FERRITE ANTENNAWhere the field strength is high, adjust the directionof this ferrite antenna for good reception, withoutusing an external antenna. lf good reception cannotbe obtained, see page g. Antenna Cmnection andGrounding.25, AM ANTENNA INPUT TERMINALConnect a lead wire or outdoor AM antenna to thisterminal if the ferrite antenna (24) cannot getgood reception.26. GND GROUND) TERMTNAL 2Connect a ground wire to this terminal.27. FM ANTENNA INPUT TERMINALSConnect an FM antenna to these terminals.NOTE: For the details of AM antenna, FMantenna and grounding, see Antennaconnection and grounding on page g,28. PRE-AMP OUTPUT TERMINALSThe outpr.rt of preamplifier stage, which is the signalhaving passed the tone control circuit is alwayssupplied to these terminals.29. MAIN-AMP INPUT TERMINALSThese are input termirEls of the power amplifierstage of Model SX-990.The PRE-AMP OUTPUT (28) and MAIN-AMPINPUT (291 terminals are connected to each otherwith the iumper plugs. With these plugs removed,the preamplifier and power amplifier stage ofModel SX-990 can be used apart. This system isconveniert for compocing s multi.amplitier systsmand other purposes.30. CENTER CHANNEL OUTPUT TERMI-NALThe signals of left and right channels are mixedtogether and supplied to this terminal at all times.The terminal may be used for composing a 3-Drystem or connecting a center-channel amplifier.31. & 32. SPEAKER OUTPUT A TERM|.NALSModel SX-990 is designed to permit connection oftw sets of stereo loudspeaker systems.Connect the first set of loudspeaker system (systemA) to these terminals; the right channel to terminal(31) and the left channel to terminal (32).33. & 34, SPEAKER OUTPUT B TERMI.NALSConnect the right channel loudspeaker of the secondloudspeaker system (system B) to terminal (33) andthe left channel loudspeaker of this system toterminal (34).For connection of loudspnakrs to the SPEAKEROUTPUT A and B terminals, the plugs supplied asaccessories must be usd. Follow the instructionsunder ConrEction of loudspeaker system on page9, for the conect use of the plugs.35. LINE VOLTAGE SELECTOR ANDFUSE HOLDERThis selector is used for setting the SX-990 to suitthe line voltge to be supplied. lt also serves 6 a fuseholder.For the selector setting and fuse replacement proce.dures, refer to the article LINE VOLTAGE SELEGTION AND FUSE. (Page 1)36. SWITCHED AUXILIARY AC OUTLETA power of 230 VA can be supplied to a tumtableor other eqipment from lis outlet. The powersupply is turned on and off corresponding to thcturningFon and off operat