Arcam-Alpha9P-int-sm维修电路原理图.pdf
ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALARCAM ALPHA 9/9P SERVICE MANUALIssue 1 Serial No. 001 - (Paul Newton July 96)Circuit DescriptionInput/Output SelectionThe Alpha 9 integrated amplifier has 6 line levelinputs and optional phono input selected by use ofthe motorised listen switch, SW201.The use of the record switch SW202 allowsrecording of one source whilst listening to another.The Processor/Tape 2 switch, SW207, allows tapemonitoring of a 3 head tape deck connected to theProcessor/Tape 2 sockets. It can also be used toallow input signals to be routed to an externalsurround decoder for processing before beingrouted back to the Alpha 9. Tone Control & Preamp Out/Power Amp InThe tone control stage on the Alpha 9 is basedaround a dual op-amp Z2. The first half providesa buffer stage for the tone controls and the secondone with its frequency dependent feedback is usedas the tone control itself.The output of the tone control then passes throughthe balance control RV201 and then onto thepower amp stages and the preamp out bufferstage formed by Z203.The tone controls and balance pot can bebypassed by use of the direct switch SW205.The Alpha 9 can be driven from an externalpreamplifier source by moving the internal switchSW206 to disconnect the Alpha 9 preamp stagesfrom the power amp.Power AmplifierThe signal from either the Alpha 9 input sockets oran external preamp enters the power amp stagevia C12 and R35. Q11, Q16 form a long, tailed pair driven by thecurrent source formed by Q18 and Q19.Q6 is the Class A stage driving the quasicomplementary output stage of Q4, Q5, andmosfets Q1, 2.The Alpha 9 and Alpha 9P utilize an auto biascircuit to maintain the correct quiescent current(IQ). The circuit works by monitoring the voltageacross the 0.22 ohm resistors R1, RA1 andcomparing it to a voltage derived from the - 44v railvia R24. Both these voltage are fed into the inputsof comparator Z3. If the voltage across the 0.22ohm resistors increases the output of thecomparator goes high impedance and Q15 isturned off. This causes capacitor C72 to dischargeand reduce the bias on the base of Q17 whichreduces the IQ. Conversely if the voltage acrossthe 0.22 ohm resistors is low then Q15 is turned onmore and C72 charges and increases the bias onQ17 and so increases the IQ. Under signalconditions a low frequency, variable mark/spaceratio, waveform can be seen on the collector oftransistor Q20 as the bias is being automaticallyadjusted. Z1 is a d.c. servo used to maintain a low d.c. offsetat the speaker outputs.Power SuppliesThe Alpha 9/9P is powered by a toroidaltransformer with 2 sets of secondary windings.The main windings are used to provide +/-44VD.C. after rectification and smoothing by diodesD201-204 inc. reservoir capacitors C201, 202.The second winding is rectified to provide anunregulated supply voltage for the motor driver ics,Z402 (for the volume control) & Z403 (for the listenselector).This unregulated supply is also smoothedand regulated with a simple stabilizer circuit (zenerdiode D402 and associated components) toprovide a stable voltage for the micro controllerZ401.Protection/ Mute circuit The protection and mute functions are carried outby Z501. This performs turn on delay, d.c. offsetdetection and thermal cutout. It also displays thestatus of the amplifier with the use of a bicolourLED - Green for ready and Amber for when thespeakers are disconnected internally because of afault condition or on initial power up whilst the 5second switch on delay mute is operating.If the unit suffers a current overload the protectioncircuit may latch and the unit will not reset until ithas been switched off and on again. If theprotection is activated by a thermal problem theunit will begin to operate again when it has cooleddown.The thermal cut out operating point is set by thethermistor TH501, mounted close to the outputdevice heatsinks.Disc Stage (optional)RadioFans.CN 收音机爱 好者资料库ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALThe optional phono stage board available for theAlpha 9 provides amplification and RIAAequalization for both moving coil (MC) and movingmagnet (MM) cartridges.Transistors Q2-5 and their associated componentsprovide the extra gain required for moving coilcartridges when required Z1 forms a flat responsegain stage with the gain set by R3 and R4. R5 andC2 provide a low pass filter used as the highfrequency part of the RIAA de-emphasis. Thenegative feedback loop around IC2, R7, 8, 9, 10and C3 provides the active low frequency RIAA de-emphasis. The pcb mounted switch selects between MM or MC.The board is powered by +/- 15V regulated rails fromthe main pcb and the +15V rail is then regulated to6.3V by Q1 and D1, D2 to power the moving coilstage.Disassembly For Servicing1.Remove the top cover and front panel.2.Remove 2 screws securing the sub front to thechassis sides and 3 screws holding thesubfront to the chassis base.3.Remove 3 screws holding the pcb to thechassis. These can be found close to the largeheatsink and also near to the mains inletsocket.4.Remove 5 screws from the rear panel, one ateach end and 3 along the bottom edge.5.Remove the transformer bolt.The pcb, with the rear panel, transformer andsubfront attached, can now be pulled backwards outof the unit.TEST POINTDC VOLTAGETP1+ 5VTP2+9.6VTP30V MUTE ON +2V MUTE OFFTP40V VOL UP +5V VOL DOWNTP5+5V VOL UP 0V VOL DOWNTP6+15VTP7-15VTP8+44VTP9-44VTEST POINTDC VOLTAGETP100.5VTP110.5VTP12-2VTP13-2VTP14+2.2VTP15+2.2VTP16+6.8VTP170V MUTE ON +2V MUTE OFFThe IQ voltage measured across the 0.22 ohmresistors R1, RA1 or R101, RA101should be about 6-7 mV.RadioFans.CN 收音机爱 好者资料库ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALAlpha 9 Integrated Amplifier Parts ListRef. No.DescriptionPart No.C1ELST 100U 25V2N710C2PEST 47N 63V 5%2K347C3ELST 100U 100V2N710BC4PCRB 100N 100V 5% RA 5mm2H410C5PPRO 680P 5% 63V RA2D168C6PSTY 56P 160V ENCAP 1PF%2F056C7ELST 10U 50V2N610C8ELST 100U 25V2N710C9PEST 15N 63V 5%2K315C10PEST 15N 63V 5%2K315C11PPRO 220P 5% 63V RA2D122C12ELST NON POLAR 10UF 35V2U610C13NPPRO 220P 5% 63V RA2D122C14NPPRO 220P 5% 63V RA2D122C15NELST 10U 50V2N610C16NPCRB 100N 100V 5% RA 5mm2H410C17NPCRB 100N 100V 5% RA 5mm2H410C18NPPRO 100P 63V 5% RA2D110NC19NPPRO 100P 63V 5% RA2D110NC20PEST 15N 63V 5%2K315C21NELST 10U 50V2N610C22PCRB 100N 100V 5% RA 5mm2H410C23PCRB 100N 100V 5% RA 5mm2H410C25NPPRO 2N2 5% 63V RA2D222C26NELST 10U 50V2N610C71ELST 10U 50V2N610C72ELST 100U 25V2N710C101ELST 100U 25V2N710C102PEST 47N 63V 5%2K347C103ELST 100U 100V2N710BC104PCRB 100N 100V 5% RA 5mm2H410C105PPRO 680P 5% 63V RA2D168Alpha 9 Integrated Amplifier Parts ListRef. No.DescriptionPart No.C106PSTY 56P 160V ENCAP 1PF%2F056C107ELST 10U 50V2N610C108ELST 100U 25V2N710C109PEST 15N 63V 5%2K315C110PEST 15N 63V 5%2K315C111PPRO 220P 5% 63V RA2D122C112ELST NON POLAR 10UF 35V2U610C113NPPRO 220P 5% 63V RA2D122C114NPPRO 220P 5% 63V RA2D122C115NELST 10U 50V2N610C116NPCRB 100N 100V 5% RA 5mm2H410C117NPCRB 100N 100V 5% RA 5mm2H410C118NPPRO 100P 63V 5% RA2D110NC119NPPRO 100P 63V 5% RA2D110NC120PEST 15N 63V 5%2K315C121NELST 10U 50V2N610C122PCRB 100N 100V 5% RA 5mm2H410C123PCRB 100N 100V 5% RA 5mm2H410C125NPPRO 2N2 5% 63V RA2D222C126NELST 10U 50V2N610C172ELST 100U 25V2N710C173ELST 100U 25V2N710C201ELST 10m 50V RA 32mm2N910C202ELST 10m 50V RA 32mm2N910C205PPRO 4N7 63V 5% RA2D247NC206PPRO 4N7 63V 5% RA2D247NC207ELST 10U 50V2N610C208ELST 10U 50V2N610C209ELST 10U 50V2N610C210ELST 10U 50V2N610C301NCERD 1N0 63V 20% RA2A210C401NELST 1M0 25V2N810ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALC402NCERD 10N 63V 20% RA2A310C403NELST 1M0 25V2N810C404CERD 10N 63V 20% RA2A310C405NCERD 10N 63V 20% RA2A310C406NCERD 10N 63V 20% RA2A310C407NCERD 10N 63V 20% RA2A310C408NCERD 10N 63V 20% RA2A310C409NCERD 10N 63V 20% RA2A310C410NELST 10U 50V2N610C411NELST 1U0 50V 20% RA2N510C501ELST 100U 25V2N710C502ELST 1U0 50V 20% RA2N510C503ELST 100U 25V2N710C504ELST 1U0 50V 20% RA2N510C505SUPPR CAP 4N7 250V2K247C506CERD 10N 63V 20% RA2A310C507CERD 1N0 63V 20% RA2A210C508CERD 1N0 63V 20% RA2A210C509CERD 1N0 63V 20% RA2A210C510CERD 1N0 63V 20% RA2A210C511CERD 1N0 63V 20% RA2A210C512CERD 1N0 63V 20% RA2A210C601NPPRO 220P 5% 63V RA2D122C602NPEST 15N 63V 5%2K315C603NCERD 10N 63V 20% RA2A310D1ZENER 10V 400MW3C11004D2RECTIFIER 1N4003F 1A 200V3B4003D3ZENER 10V 400MW3C11004D4ZENER 10V 400MW3C11004D5ZENER 5V6 400MW3C05604D6ZENER 22V 400MW3C22004D101ZENER 10V 400MW3C11004D102RECTIFIER 1N4003F 1A 200V3B4003D103ZENER 10V 400MW3C11004D104ZENER 10V 400MW3C11004D106ZENER 22V 400MW3C22004D201RECTIFIER MUR420 4A 220V3B420D202RECTIFIER MUR420 4A 220V3B420D203RECTIFIER MUR420 4A 220V3B420D204RECTIFIER MUR420 4A 220V3B420D401NRECTIFIER 1N4003F 1A 200V3B4003D402NZENER 5V6 400MW3C05604D403NRECTIFIER 1N4003F 1A 200V3B4003D404NZENER 5V6 400MW3C05604D405NZENER 5V6 400MW3C05604D406NSSDIODE 1N4148 75V3A4148D407NRECTIFIER 1N4003F 1A 200V3B4003D408NZENER 5V6 400MW3C05604D501RECTIFIER 1N4003F 1A 200V3B4003D502RECTIFIER 1N4003F 1A 200V3B4003D503RECTIFIER 1N4003F 1A 200V3B4003D504RECTIFIER 1N4003F 1A 200V3B4003D505NRECTIFIER 1N4003F 1A 200V3B4003D602ZENER 5V6 400MW3C05604F501INS COVER PCB FUSEHOLDERF022F501FUSEHOLDER 20mm PCB8S004F501SPARE FUSE 20mm 1.6A ASC12166FS502INS COVER PCB FUSEHOLDERF022FS502FUSEHOLDER 20mm PCB8S004HS1ALPHA9 & AV50 HEATSINKE801HKHS201HEATSINK TO220 13 DEGC/WF005HS201HEATSINK CLIP TO220 13/8.6 DC/WF006HS202HEATSINK TO220 CLIP 23DEG/WF004KP1KWIKSTIK PAD S/A 25 X 12mmF157SKP2KWIKSTIK PAD S/A 25 X 12mmF157SL1INDUCT 2U2 15x25mm AD20187D002AL101INDUCT 2U2 15x25mm AD20187D002ALED601LED RED/GREEN 5MM3D002ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALLK401NJUMPER 3 WAY x 125mmL815CALK501NLINK BANDOL PREFORM 10mm1X010ALK601JUMPER 3 WAY x 125mmL815CAMIMAINS SWITCH SD33P INSULATORE00301MSMAINS SWITCH SPACERE66901PL1N2WAY MOLEX VERT MALE CONNECTOR8K6201Q1TRANS POWER MOSFET IRPF2404K240Q2TRANS POWER MOSFET IRPF2404K240Q3TRANS LF SS P 2SA10854A1085Q4TRANS LF SS N 2SC25474A2546Q5TRANS LF SS P 2SA10854A1085Q6TRANS LF SS P BC556B4A556Q7TRANS LF SS N BC546B4A546Q8TRANS LF SS P BC556B4A556Q9TRANS LF SS N BC546B4A546Q10TRANS LF SS P BC557B4A557Q11TRANS LF SS N BC547B4A547Q12TRANS LF SS N 2SC25474A2546Q13TRANS LF SS P BC557B4A557Q14TRANS LF SS N 2SC25474A2546Q15TRANS LF SS P BC557B4A557Q16TRANS LF SS N BC547B4A547Q17TRANS LF SS N BC547B4A547Q18TRANS LF SS N BC547B4A547Q19TRANS LF SS N BC547B4A547Q20TRANS LF SS N BC547B4A547Q101TRANS POWER MOSFET IRPF2404K240Q102TRANS POWER MOSFET IRPF2404K240Q103TRANS LF SS P 2SA10854A1085Q104TRANS LF SS N 2SC25474A2546Q105TRANS LF SS P 2SA10854A1085Q106TRANS LF SS P BC556B4A556Q107TRANS LF SS N BC546B4A546Q108TRANS LF SS P BC556B4A556Q109TRANS LF SS N BC546B4A546Q110TRANS LF SS P BC557B4A557Q111TRANS LF SS N BC547B4A547Q112TRANS LF SS N 2SC25474A2546Q113TRANS LF SS P BC557B4A557Q114TRANS LF SS N 2SC25474A2546Q115TRANS LF SS P BC557B4A557Q116TRANS LF SS N BC547B4A547Q117TRANS LF SS N BC547B4A547Q118TRANS LF SS N BC547B4A547Q119TRANS LF SS N BC547B4A547Q120TRANS LF SS N BC547B4A547Q121TRANS LF SS P 2SA10854A1085Q401NTRANS LF SS N BC547B4A547Q402NTRANS LF SS P BC557B4A557Q403NTRANS LF SS P BC557B4A557Q502TRANS LF SS N 2SC25474A2546R1RES MO 3W 5% 0R22 KOASPR31Q922R2RES CF 1W 1R5 5%1E815R3RES CF 1W 5R6 5%1E856R4RES MF FU W3 100R 5% NFR251G110R5RES MF W4 470R 1%1H147R6RES MF FU W3 100R 5% NFR251G110R7RES MF W4 470R 1%1H147R8RES MF FU W3 100R 5% NFR251G110R9RES MF W4 1K0 1%1H210R10RES MF W4 1K0 1%1H210R11RES MF FU W3 220R 5% NFR251G122R12RES MF FU W3 220R 5% NFR251G122R13RES MF FU W3 470R 5% NFR251G147R14RES MF FU W3 470R 5% NFR251G147R15RES MF W4 1K0 1%1H210R16RES MF W4 18K 1%1H318R17RES MF W4 5K6 1%1H256ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALR18RES MF W4 2K7 1%1H227R19RES MF W4 2K7 1%1H227R20RES MF W4 4K7 1%1H247R21RES MF W4 330R 1%1H133R22RES MF W4 2K7 1%1H227R23RES MF W4 100R 1%1H110R24RES MF W4 220K 1%1H422R25RES MF W4 18K 1%1H318R26RES MF W4 2K7 1%1H227R27RES MF W4 5K6 1%1H256R28RES MF FU W3 10R 5% NFR251G010R29RES MF FU W3 470R 5% NFR251G147R30RES MF W4 100K 1%1H410R31RES MF W4 120K 1%1H412R32RES MF W4 47K 1%1H347R33RES MF W4 470K 1%1H447R34RES MF W4 47K 1%1H347R35RES MF W4 2K7 1%1H227R36NRES MF W4 5K6 1%1H256R37NRES MF W4 6K8 1%1H268R38NRES MF W4 6K8 1%1H268R39NRES MF W4 12K 1%1H312R40NRES MF W4 6K8 1%1H268R41NRES MF W4 10K 1%1H310R42NRES MF W4 12K 1%1H312R43NRES MF W4 470R 1%1H147R46NRES MF W4 100K 1%1H410R47NRES MF W4 4K7 1%1H247R48NRES MF W4 4K7 1%1H247R49NRES MF W4 1K8 1%1H218R50NRES MF W4 6K8 1%1H268R51NRES MF W4 100R 1%1H110R52RES MF W4 6K8 1%1H268R53RES MF W4 2K2 1%1H222R54NRES MF W4 1K8 1%1H218R55NRES MF W4 1K0 1%1H210R56RES MF W4 56R 1%1H056R57NRES MF W4 100K 1%1H410R58RES MF W4 330R 1%1H133R59RES MF W4 27K 1%1H327R60RES MF W4 1K0 1%1H210R61RES MF W4 33K 1%1H333R62NRES MF W4 820R 1%1H182R71RES MF W4 15K 1%1H315R72RES MF W4 15K 1%1H315R73RES MF W4 15K 1%1H315R74RES MF W4 15K 1%1H315R75RES MF W4 10K 1%1H310R76RES MF W4 12K 1%1H312R77RES MF W4 220K 1%1H422R78RES MF W4 120K 1%1H412R79RES MF W4 33K 1%1H333R80RES MF W4 1K5 1%1H215R81RES MF W4 2K2 1%1H222R82RES MF W4 100R 1%1H110R83RES MF W4 4K7 1%1H247R84RES MF W4 18K 1%1H318R101RES MO 3W 5% 0R22 KOASPR31Q922R102RES CF 1W 1R5 5%1E815R103RES CF 1W 5R6 5%1E856R104RES MF FU W3 100R 5% NFR251G110R105RES MF W4 470R 1%1H147R106RES MF FU W3 100R 5% NFR251G110R107RES MF W4 470R 1%1H147R108RES MF FU W3 100R 5% NFR251G110R109RES MF W4 1K0 1%1H210R110RES MF W4 1K0 1%1H210R111RES MF FU W3 220R 5% NFR251G122ALPHA 9/9P SERVICE MANUALALPHA 9/9P SERVICE MANUALR112RES MF FU W3 220R 5% NFR251G122R113RES MF FU W3 470R 5% NFR251G147R114RES MF FU W3 470R 5% NFR251G147R115RES MF W4 1K0 1%1H210R116RES MF W4 18K 1%1H318R117RES MF W4 5K6 1%1H256R118RES MF W4 2K7 1%1H227R119RES MF W4 2K7 1%1H227R120RES MF W4 4K7 1%1H247R121RES MF W4 330R 1%1H133R122RES MF W4 2K7 1%1H227R123RES MF W4 100R 1%1H110R124RES MF W4 220R 1%1H122R125RES MF W4 18K 1%1H318R126RES MF W4 2K7 1%1H227R127RES MF W4 5K6 1%1H256R128RES MF FU W3 10R 5% NFR251G010R129RES MF FU W3 470R 5% NFR251G147R130RES MF W4 100K 1%1H410R131RES MF W4 120K 1%1H412R132RES MF W4 47K 1%1H347R133RES MF W4 470K 1%1H447R134RES MF W4 47K 1%1H347R135RES MF W4 2K7 1%1H227R136NRES MF W4 5K6 1%1H256R137NRES MF W4 6K8 1%1H268R138NRES MF W4 6K8 1%1H268R139NRES MF W4 12K 1%1H312R140NRES MF W4 6K8 1%1H268R141NRES MF W4 10K 1%1H310R142NRES MF W4 12K 1%1H312R143NRES MF W4 470R 1%1H147R146NRES MF W4 100K 1%1H410R147NRES MF W4 4K7 1%1H247R148NRES MF W4 4K7 1%1H247R149NRES MF W4 1K8 1%1H218R150NRES MF W4 6K8 1%1H268R151NRES MF W4 100R 1%1H110R152RES MF W4 6K8 1%1H268R153RES MF W4 2K2 1%1H222R154NRES MF W4 1K8 1%1H218R155NRES MF W4 1K0 1%1H210R156RES MF W4 56R 1%1H056R157NRES MF W4 100K 1%1H410R158RES MF W4 330R 1%1H133R159RES MF W4 27K 1%1H327R160RES MF W4 1K0 1%1H210R161RES MF W4 33K 1%1H333R162NRES MF W4 820R 1%1H182R173RES MF W4 15K 1%1H315R174RES MF W4 15K 1%1H315R175RES MF W4 10K 1%1H310R176RES MF W4 12K 1%1H312R177RES MF W4 220K 1%1H422R178RES MF W4 120K 1%1H412R179RES MF W4 33K 1%1H333R180RES MF W4 1K5 1%1H215R181RES MF W4 2K2 1%1H222R182RES MF W4