Pioneer-SX1280-rec-sm电路图 维修手册.pdf

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1、XRABi3 RadioFans.CN 收音机爱 好者资料库 TypoVolr.rp R.mark! KU120V onlyU.S.A. rnodel KC120V only Canads model 110v, 120v. 22OV and 240V (Switchsble)Gen6ral exDort model s/G110V, 120V, 220V.nd 240V $i,itchsbl6lU.S. Milit8ry model six-1 eEto MODEL SX-1280 COMES IN FOUR VERSIONS DTSTINGUISHED AS FOLLOWS: NOTICE

2、: r This service manual is applicable to the KU and KC types . As to the S and S/G types, please refer to page 81. CONTENTS 1. SPECIFTCAT|ONS. 3 2, CONNECTION DIAGRAM 5 3. FRONT PANEL FACILITIES 7 4. LEVEL DTAGRAM . . . . 10 5. BLOCK DIAGRAM . . . 11 6. CIRCUIT DESCRPTIONS 6.1 Tuner Section .13 6.2

3、AF Section .14 6.3 Power Supply Circuit . .16 6.4 Proteqtion Circuit. .11 7, DTSASSEMBLY . 18 8, PARTS LOCATION 8.1 Front Panel View. .20 8.2 Front View with Panel Removed .21 8 . 3 T o p V i e w . . . . . . . 2 2 8.4 Bottom View .29 8.5 Rear Panel View . . . . . . 24 9. DIAL CORD STRINGING . . . .

4、. 25 RadioFans.CN 收音机爱 好者资料库 IO. ADJUSTMENTS 10.1 FM Tuner 1O.2 AM Tuner 10.3 Power Amplifier 10.4 Meter Amplif ier 11. EXPLODED VIEWS 11.1 External Part . , . 11,2 lnternal Part 12. PACKING 13. SCHEMATIC DIAGRAMS, P.C. BOARD PATTERNS AND PARTS LIST 13.1 Schematic Diagram and Miscellaneous Parts . .

5、 13.2 Tuner Assembly (AWE-092) 13.3 Microphone Jack Assembly (GWM-I05) 13.4 Cartridge Load Assembly (cWS-134) 13.5 Function Switch Assembly (GWS-I33) 13.6 EO Amplifier Assembly (AWF-031) . . . . . 13.7 Flat Amplifier Assembly (AWG-0601 13.8 Tone Amplifier Assembly (AWG-059) . . . . 13.9 Filter Ampli

6、f ier Assembly (AWM-119) 13.10 Power Amplifier Assembly (AWH.074) 13.11 Resistor Assembly (AWX-I27) 13.12 Meter Amplifier Assembly (AWM-I211 13,13 Power Supply Assembly AWR-I57) . . . . 13.14 Fuse Assembly (AWX-I261 or (AWX-I391 13.15 Protection Circuit Assembly (AWM-I23) ADDITIONAL SERVICE MANUAL 2

7、7 29 30 30 31 33 40 41 45 52 53 54 56 58 61 64 67 70 72 74 77 78 1. SPEC|F|CAT|ONS . . . . . 82 2. CONTRAST OF MISCELLANEOUS PARTS ,. 82 3. EXPLODED VIEW . . . . 84 4. SCHEMATIC DIAGRAMS, P.C. BOARD PATTERNS AND PARTS LIST Schernatic Diagram . . . gs 5P Connector Assembly (AWX-062) . . g7 Fuse Assem

8、bly (AWX-134) .88 NO?E: * .Fnse ossembly (AWX-I26) is applicable to the KII type, and AWX-tB9 is for the KC type. 4.1 4.2 4.3 e RadioFans.CN 收音机爱 好者资料库 1. SPECIFICATIONS Semiconductors F E T S . . . 5 l C s . . . . . 6 T r a n s i s t o r s . . . . . . 6 1 D i o d e s . . . . . . . . 5 0 Power Ampli

9、fier Section Continuous power output of 185 watts. per channel, min., at 8 ohms from 20 Hertz to 20,000 Hertz with n0 more than 0.03% total harmonic distortion. Total Harmonic Distortion (20 Hertz to 20,000 Hertz) Continuous Rated Power Output . .No more than 0.03% 90 watts per channel power output,

10、 S ohms . . No more than 0.01% I watt per channel Power output, S ohms . . No more than 0.01% Intermodulation Distortion (50 Hertz: 7,000 Hertz = 4:1) Continuous Rated Power Output . . No more than 0.01% 90 watts per channel power output, 8 ohms No more than 0.006% 1 watt per channel power output,8

11、ohms No more than 0.005% Frequency Response . . . 5 Hertzto IO,OOOHertzl!aA lnput Sensitivity/ lm pedance P O W E R A M P I N . . . . . . . l V / 5 O k i l o h m s Output SPEAKERS . . . . . A, B, C, A+8, B+C, C+A Damping Factor ( 2 0 H e r t z t o 2 0 , 0 0 0 H e r t z , 8 o h m s ) . . . . . . . .

12、. . . 3 0 Hum and Noise (lHF, short-circ u ited, A Network). . 105d8 Preamplifier Section Input (sens itiv ity/ lm pedance) PHONO I . Cartridge load (capacitance) . . . PHONO 2 t 4 t c . . . . .2.5mV/50kilohms 100, 200, 300, 400pF . . . 2.5mV/50 kilohms . . . 7.5mV/50 kilohms AUX. . l50mV/50 kilohms

13、 TAPE PLAY1 . 150mV/50 kilohms TAPE PLAY2. 150mVi50 kilohms PHONO Overload Level (1kHz;T.H.D: 0.03%) P H O N O l , 2 . . . . . . 3 0 0 m V Output Level/l mpedance T A P E R E C l . . . . . . . . 1 5 0 m V T A P E R E C 2 . . . . . . 1 5 0 m V P R E O U T . . . . . 1 V / 1 k i l o h m s Total Harmoni

14、c Distortion (20H2 to 20,000H2, 1V output). . .No more than 0.01% Frequency Response PHONO(RIAA equalization). 20Hz to 20,000H2 l0.2dB Tone Control B A S S . . . T R E B L E . Filter L O W . . . sx-,| 480 . ,LlOdB (l00Hz) main control a5dB (50H2) sub control . r10dB (1okHz) main control e5dB (20kHz)

15、 sub control H I G H . . . Loudness Contour (Volume control set . 15Hz (12dBloct.) . 8kHz (l2dB/oct.) at -40dB position) . . . . +6dB (100H2), +3Og 1l6kli.1 Hum and Noise (lH F, short-circuited, A Network) PHONO . AUX, TAPE PLAY , . . Muti ng . FM Tuner Section Usable Sensitivity t40No . 50dB Quieti

16、ng Sensitivity M O N O . . STEREO. Signal-to-Noise Ratio (at 75dBf) . . .STEREO . (at 65dBf) .MONO. STEREO. Distortion (at 65dBf) f00Hz MoNo/STEREO . .o.1%1o.2% lkHz MONO/STEREO . O.1o/o10.1570 6kHz I4ONO/STEREO . . 0.1YolO.2% Frequency Response . . . 3OHzto 15,O0OHzl33dB C a p t u r e R a t i o . .

17、 . . . . . . . . 1 . 0 d B A l ternateC hannel S el ecti vi ty .80d8 S puri ous R esponse R ati o . . . .100d8 l m a g e R e s p o n s e R a t i o . . . . . . . . . . . . . 9 0 d 8 l F R esponse R ati o . .110d8 A M S uppressi on R ati o. .55d8 Muting Threshold . . 19.2dBf(5gV) Stereo Separation . .

18、 . 50dB(lkHz), 35dB(30H2 - 15kHz) S u b c a r r i e r P r o d u c t R a t i o . . . . . . . . . . . 6 5 d 8 S C A R e j e c t i o n R a t i o . . . . . . . . . . . . . . 6 5 d 8 Antenna Input 300 ohms balanced 75 ohms unbalanced . . . 8 0 d 8 . . . 95dB . . -20d8 AUX, TAPE PLAY. . . 5Hz to S0,OOOHZI

19、?dB AM Tuner Section S ensit iv it y (lH F, Fe r r i t e a n t e n n a ) . . . . . . . . . . (lHF, Ext. antenna) . Selectivity Signal-to-Noise Ratio. . . . . . . lmageResponse Ratio . . . . . . l F R e s p o n s e R a t i o . . . . . . . . . Antenna. . Built-in 300!V/m . . 15pV . . . 30dB . . . 5 0

20、d 8 . . . 40dB . . . . . . 4 0 d B Ferrite Loopstick Antenna Misdellaneous P o w e r R e q u i r e m e n t s . . . . . . . . . . 1 2 0 V 6 0 H z PowerConsumption . 430W(UL), 1000VA(CSA) 1 100W (max.) Dimensions . 556(W) x i86(H) x461(D) mm 21-1 1/l6(w) x 6-1sll6(H) x 17-5l16(D) in Weight Without Pac

21、kaSe. . 28.7kg (631b 3oz) With Package Furnished Parts . 32.1kg (701b 10oz) F M T - t y p e A n t e n n a . . . . . . . . . . 1 O p e r a t i n g I n s t r u c l i o n s . . . . . . . . 1 Hex. Wrench 1 *Meacurcd pursudnt to the Federal Trade Commissions Trade Regulation rule on Pouer Output Claifis

22、for Amplifierc. NO?E: Specificotions dnd the design subject to possible modifico- tion uithout aotice due to improuements. HEX. WRENCH The accessory hexagonal wrench is provided for removing the TUNING knob and VOLUME knob or tightening their set screws should they become loose. If required, loosen

23、the set screw by inserting the wrench into the hole on the side.of the knob and tuming the wrench counter-clockwise. Be particularly careful not to scratch the front panel when employing the wrench. 2. CONNECTION DIAGRAM Turntable I (PHONO 1) AM outdoor antenna Cartridge type player (AUX) -t set to

24、ON, because the muting circuit has been actuated to suppress the unpleasant noise that is sometimes generated when the power is switched on and off. PHONES JACK Plug the headphones into this jack when you want to listen through your stereo headphones. Release the all SPEAKERS buttons if you want to

25、listen to the sound through your headphones only (This means that all three buttons will be released). SPEAKERS BUTT Press the button corresponding to the speakers connerrted to the SPEAKERS terminals (A, B, C) on the rear panel. You can presr two of these buttons to listen to sound from two pairs o

26、f speaker systems at the same time. NOTE: No ound utill be heard through the speahers if all lhree buttou are p?esed ot lhe same time. BALANCE CONTROL Use thir control to balance the volume of the left and right chennels. First, however, set the MODE switch to MONO, and adiust so that the sound appe

27、ars to c,)me from somewhere exactly between the two speakers. ll the sound appears to be louder on the right, it means that the volume of the right channel is higher. Turn the BALAIICE control to the left and adiust. Conversely, if the sound appears to be louder on the left, it means that the volume

28、 of the left channel is higher. Therefore, turn the BALANCE control to the right and adiust. After adjust- ing, return the MODE switch to STEREO. POWER METERS These power meters allow you to read out the rated power level when speakers with a nominal impedance of 8 ohms are connected to the receiver

29、s speaker terminals. NOTE: These ualues are related to the impedance of the speahers and they wry accprding to the frequency. In order to find out the exact output leuel, connect an 8-ohm dummy load instead of the speahers. FUNCTION INDICATOR MEMORY MARKERS These are very convenient for frequent tun

30、ing in to the same broadcasting station. MUTING SWITCH Set this switch to the -20d8 position to attenuate the audio output indicated by the VOLUME control by 20d8. There is no need to adiust the VOLUME control if you use this switch when turning down the audio output temporarily and when changing ov

31、er records or tapes. VOLUME CONTROL Use this control to adlust the output level to the speakers and headphones. Turn it clockwise to increase the output level. No sound will be heard if you set it to -. The scale is graduated in dB which indicate the attenuation when the maximum output level is 0dB.

32、 ti t tl II I I I Irt Iti il l,l I _rEeLE_ tw ,oi! - + -.,E;lia- o.,r E r:f o osss$:ffl # OErEn _TONE SWITCH Set this switch to ON when adjusting the BASS and TREBLE controls. In the OFF position, it causes the amplifier to operate with a flat frequency response. FUNCTION BUTTONS Press the function

33、button which corresponds to the pro- gram source. Turn the VOLUME control down first before selecting a different function button while the sound from one program source is being reproduced. FM. . . . . Press this button for FM broadcasts. The FM STEREO indicator tights up when the receiver is tuned

34、 in to an FM stereo broadcast. The sound is auto- matically received monophonically during FM monophonic broadcasts. TWIN BASS AND Use these controls TREBLE CONTR to adjust the bass and the treble. TAPE DUPLICATE SWITCH Set this switch to ON when you want to duplicate or edit a pre-recorded tape usi

35、ng two tape decks. TAPE MONTTOR SWTTCHES (1,2) Set switch I to ON with a tape deck which is connected to the TAPE 1 jacks (REC and PLAY) when you wanr to monitor the playback or recording of a tape. The tape on a deck which is connected to the TApE 2 jacks (REC and PLAY) can be similarly monitored b

36、y setting switch 2 to oN. NOTE: Set these switches to the upper (offl position when Iistening to records or a broadcast. A M . . . A U X . . PHONO 2IMIC . . Press this button for AM broadcasts. Press this button when listening to an audio component cornected to the AUX input jacks. Press this button

37、 when playing a record on the turntable connected to the PHONO 2 iacks, or when using a microphone which you have plugged into the MIC iack. Press this button when playing a record on the turntable connected to the PHONO i jacks. P H O N O 1 . . . . . NOTES: 1. Unplug the microphone from the MIC jac

38、h when you do not intend to use the microphone otherwise you will not be able to use the PHONO 2 jachs. 2. Only one function button should be pressed at a time. Plug your microphone into this lack. The microphone signals are reproduced in mono through the left and right speakers. a ti I r I t l t l

39、L t t t U ttl I I t l . , t : I EEE! ffi gt trED - TUNING METER When tuning in to an FM station, the optimum reception position is indicated when the metei pointer deflects to dead center. Check that the SIGNAL meter pointer has deflected as far to the right as possible. SIGNAL METER When tuning in

40、to an AM or FM station, the optimum reception position is indicated by the maximum deflec. tion of the meter pointer to the right. FM MULTIPATH BUTTON Use this switch to detect multipath sound when installing the FM antenna in a position which yields the minimum multipath interference. STEREO INDICA

41、TOR FILTER 15Hz BUTTONS . When this button is pressed, a 12dB/oct atten- uation can be provided for frequencies below l5Hz. This means that you can cancel out noise in the ultra-low frequencies which is generated by low-pitched rumble from a turntable and other forms of distortion. Although this noi

42、se cannot be heard, it can generate intermodula- tion distortion. 8kHz . . Press this button to provide a l2dBloct atten- uation at frequencies above 8kHz. Set it to this position when you find high-frequency noise, such as that from scratched records, unpleasant. FM 25ps BUTTON Press this button wh

43、en listening to a *Dolby FM broad- cast; otherwise keep this button at the released position. sx-1 eao PHONO 1 CARTRIDGE LOAD SWITCH Use this knob to select the input capacitance (pF) in accordance with the sp.ecified load capacitance of the moving magnet (MM) cartridge connected to the PHONO 1 jack

44、s. TUNING KNOB Use this to tune in to broadcasting stations. Select the station and tune for optimum reception by observing the SIGNAL meter for AM stations and both the SIGNAL and TUNING meters for FM stations. MODE SWITCH Use this switch for selecting mono or stereo performances. STEREO: Set to th

45、is position for normal stereo opera- tion. MONO:When set to this position, the left and right channel signals will be mixed and reproduced monophonically from both speaker systems. FM MUTING BUTTON ON (released position) . . . Release this button to sup- press unpleasant inter-station noise when tun

46、ing in to FM statio ns. OFF (depressed position) . Depress this. button to pick up weal( stattons. It t, ill /t I l t t l It $ 5-,6t* OFOTEn sE FrcErvr Sx-1eAO 5. BLOCK DIAGRAM ANTENNA t- F M A M L A U X PHONO I PHONO 2 M l c R PHONO 2 PHONO I A U X L# GND -+7 16 9.? Ortver Of pOWer Omp. i c,rc le g

47、mpl tf ier r A: 3- ir, rer r - e a n l r n l V e r q . 5 1 ! l r f r Q r - . . . -J_ Ss : CARTRIDGE LOAD ( lCO , 200,30C, 400 ) pF g7 : FM MUTING ( on - off ) Se : MULTI PATH ( on - off t Ss: 0E - EMPHASIS llrs - 75ps ) Sro : 0UPLICATE ( on - off ) Srr : MONlT0R 1 ( on -off ) 512: MONlT0R 2 (on-gl!

48、) Srs: ADAPTOR ton-ql Stc: M00E ( Stereo - Mono ) Sts: MUTING ( -20d8 - oft ) Sre : LOUDNESS ( on - orl ) Srr: T0NE ( on - off ) 6. CIRCUIT DESCRIPTIONS Refer to the block diagram on page 11 and the schematic on page 43 for the circuit composition of this unit. 6.1 TUNER SECTION AM Tuner The AM tune

49、r employs a 2-gangvariable capaci- tor, one IC (HA1197) and one AM ceramic filter. Its block diagram is given in Fig. 1. HA1L97 is an IC containing an RF amplifier, converter, 2-stage IF amplifier, detector, and AGC circuit, and features excellent AF frequency re- sponse and distortion. Q1 of the output circuit is a special AM muting circuit. T