Arcam-7R-int-sm维修电路原理图.pdf

ALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL1Arcam Alpha One/ 7R/ 8R/ 8P Amplifier Service ManualIssue 1 Serial Number 001 - (Paul Newton/ Haider Bahrani Sept 98)Circuit DescriptionThe Alpha One / 7R/8R and 8P share a commonpcb. The circuits are very similar and the maindifferences are the remote volume facility and extrapower output on the 7R and 8R and a switch tobypass the phono stage to enable its use as an extraline level input and the AV processor switch on theAlpha 8R integrated amplifier. The 8P poweramplifier utilises the same power amplifier circuit asthe Alpha 8R integrated amplifier. Power SuppliesThe ac output of the toroidal mains transformer isrectified and smoothed by D201-204 and C204, 205.This is then regulated to +/-15V by Z201, 202 topower the phono and tone control stages and thed.c. servo.The Alpha 7R and 8R transformers have an extratapping which is used for the remote volume circuit.The ac in is regulated to 5V by zener D902 andassociated components and this is then used topower the microcontroller Z901 and remote receiver.Phono Stage (Not applicable to Alpha One)The phono stage consists of a dual opamp Z305, oneopamp per channel. The RIAA equalization isachieved by the feedback components R703, 704,702 and C704, 705, 702 on left channel (R603 etc.as above for Right channel). R703 determines thegain and C703 the low frequency roll off.On the Alpha 8R this stage can be bypassed by useof switch SW302 to enable use as an extra line input.Tone ControlsThe tone control stage is based around Z304 a dualop amp.The range of the controls is set by R507, 508 for thebass pot RV302 and R509, 510 for the treble potRV303.The tone controls and balance pot can be bypassedby use of the direct switch, SW304.Power AmplifierThe input to the power amplifier from previous stagesis fed to the differential input of Q112 and Q113. Q110 and Q111 form a constant current source for the differential input stage.The output devices are n channel mosfets SMF045.Zener diodes D103,104 limit the voltage swing withinsafe limits for the output devices & fusible resistorsR105, 106 provide overcurrent damage to thedevices.A proportion of the output current appears across theprotection network R41,42. If this becomes too highQ17 is turned on and mutes the output. High D.C.levels at the output will also mute the output. Thereare no output fuses on the Alpha One, 7R and8R/8P amplifiers. The muting is done by the mute icZ303 and its associated compontents. The muteoperates on switch on/off and if an over current orover voltage condition occurs. The power led glowsamber when the mute circuit is operative and glowsgreen in normal use.Removing the Alpha One/ 7R/ 8R/ 8P TransformerThe toroidal transformer is extremely well secured tothe main pcb with a double sided adhesive gasket.To remove the transformer you must break thisadhesive bond by cutting through the gasket. Thiswill be easier if the transformer is warm.Use a cheese wire under the transformer, pullingbackwards and forwards under tension to graduallycut through. Once most of the adhesive is cut, youshould be able to pull the transformer away from thepcb.A less satisfactory substitute for cheese wire is to usesome 22 gauge tinned copper wire, stretched first toremove kinks, and two temporary handles.Alpha One/7R/ 8R/ 8P Quiescent Current (IQ)SettingsWhen replacing the output transistors of the aboveamplifiers it is important to reset the quiescentcurrent (IQ) to the correct value to prevent theamplifier blowing again.The IQ should be checked and set by following theprocedure below:From cold and with no load or signal connectedTurn both IQ presets (RV1 and RV101) down tominimum (fully anticlockwise) and set the voltagedrop across resistor R1 (R101 for right hand channel)to between 3.0 and 3.5mV for the Alpha One and 7RRadioFans.CN 收音机爱 好者资料库ALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL2amps or between 2.3 and 2.8mV for the Alpha 8R/8Pamps.Leave the unit for 1 minute and reset to these valuesif required.Leave the unit for a further 5 minutes and reset ifrequired.The IQ is now set and the unit can be connected tospeakers and fully checked out.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 1 screw holding the pcb to thechassis. This can be found near to the mainsinlet socket.4.Remove 5 screws from the rear panel, one ateach end and 3 along the bottom edge.5.Remove the transformer bolt.6.Release the PCB pillar located near to theserial number on the pcb.The pcb, with the rear panel, transformer andsubfront attached, can now be pulled backwards outof the unit.TEST POINT VOLTAGESTest PointDC Voltage Alpha OneDC Voltage Alpha 7RDC Voltage Alpha 8R/8P132.8V35V37V227.8V29V31V315V15V15V4-32.8V-35V-37V527.8V-29V-31V6-15V-15V-15V7N/A0.09V0.09V8N/A0.10V0.10V90.3V0.27V0.27V103.4V3.2V2.9V1132.8V35V37V12-3V-2.7V-2.5V1332.8V-35V-37VBetween 14 & 153.0 -3.5mV3.0-3.5mV2.3-2.8mV16 (protection off)0.0V0.0V16 (protection on)0.6V0.6V170.0V0.0V180.0V0.0V190.0V0.0VRadioFans.CN 收音机爱 好者资料库ALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL3Test PointDC Voltage Alpha OneDC Voltage Alpha 7RDC Voltage Alpha 8R/8P200.0V0.0V0.0V21 (protection off)1.6V1.6V1.6V21 (protection on)5.0V5.0V5.0V220.58V0.17V0.17V233.4V3.1V3.1V24-3V-2.7V-2.7V25-26V-29V-29VBetween 26 & 273.4mV3.4mV2.5mV28 (muted)35V35V35V28 (protection off)1V1V1V29N/A5V5V30N/A10.510.5V31(volume going up)N/A0V0V31(volume going down)N/A5V5V32(volume going up)N/A0V0V32(volume going down)N/A5V5VPARTS LISTSThe parts for all the units are as the Alpha 7 except where shown.REFDescriptionPart NoProductC1ELST 100U 100V2N710B7RC2PEST 47N 63V 10%2K3477RC3PCRB 100N 100V 5% RA5mm2H4107RC4PEST 47N 63V 10%2K3477RC5PSTY 33P 160V ENCAP1PF%2F0337RC7PPRO 4N7 63V 5% RA2D247N7RC8PPRO 100P 63V 5% RA2D110N7RC9ELST 100U 25V2N710A1C10ELST 22U 20V OSCON2P6227RC10ELST 22U 63V ELECT2N622A1C11ELST 100U 100V2N710B7RC12ELST 100U 100V2N710B7RC13PEST 15N 63V 10%2K3157RC14PEST 15N 63V 10%2K3157RC15SUPPR CAP 4N7 250V2K2477RC16ELST 100U 25V2N7107RC17CERD 470P 63V 20% RA2A1477RC18CERD 1N0 63V 20% RA2A2107RC19ELST 100U 25V2N7107RC20CERD 470P 63V 20% RA2A1477RC21CERD 10N 63V 20% RA2A3107RC22CERD 10N 63V 20% RA2A3107RC23SUPPR CAP 4N7 250V2K2477RC24PPRO 4N7 63V 5% RA2D247N7RC25PCRB 100N 100V 5% RA5mm2H4107RC26PCRB 100N 100V 5% RA5mm2H4107RC27ELST 220U 16V2N7227RC28PCRB 100N 100V 5% RA5mm2H4107RALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL4C29ELST 1U0 50V 20% RA2N5108RC30ELST 22U 63V ELECT2N6227RC30ELLL 47U 10V ELECT2R647A1C30ELEC 10U 25V CERAFINE2P610CC8RC101ELST 100U 100V2N710B7RC102PEST 47N 63V 10%2K3477RC103PCRB 100N 100V 5% RA5mm2H4107RC104PEST 47N 63V 10%2K3477RC105PSTY 33P 160V ENCAP1PF%2F0337RC107PPRO 4N7 63V 5% RA2D247N7RC108PPRO 100P 63V 5% RA2D110N7RC109ELST 100U 25V2N710A1C110ELST 22U 20V OSCON2P6227RC110ELST 22U 63V ELECT2N622A1C111ELST 100U 100V2N710B7RC112ELST 100U 100V2N710B7RC113PEST 15N 63V 10%2K3157RC114PEST 15N 63V 10%2K3157RC116ELST 100U 25V2N7107RC117CERD 470P 63V 20% RA2A1477RC118CERD 1N0 63V 20% RA2A2107RC119ELST 1U0 50V 20% RA2N5107RC120CERD 470P 63V 20% RA2A1477RC121ELST 1U0 50V 20% RA2N5107RC122ELST 100U 25V2N7107RC123ELST 100U 25V2N7107RC124PPRO 4N7 63V 5% RA2D247N7RC125PCRB 100N 100V 5% RA5mm2H4107RC126PCRB 100N 100V 5% RA5mm2H4107RC127ELST 220U 16V2N7227RC128PCRB 100N 100V 5% RA5mm2H4107RC130ELST 22U 63V ELECT2N6227RC130ELLL 47U 10V ELECT2R647A1C130ELEC 10U 25V CERAFINE2P610CC8RC200CERD 1N0 63V 20% RA2A2107RC201SUPPR CAP 4N7 250V2K2477RC204ELST 10m 50V RA 32mm2N9107RC204ELST 6M8 35V RA2N868A1C205ELST 10m 50V RA 32mm2N9107RC205ELST 6M8 35V RA2N868A1C206PCRB 100N 100V 5% RA5mm2H4107RC207PCRB 100N 100V 5% RA5mm2H4107RC208PPRO 4N7 63V 5% RA2D247N7RC209PPRO 4N7 63V 5% RA2D247N7RC210ELST 10U 50V2N6107RC211ELST 10U 50V2N6107RC212CERD 10N 63V 20% RA2A3107RC213CERD 10N 63V 20% RA2A3107RC214CERD 10N 63V 20% RA2A3107RC215CERD 10N 63V 20% RA2A3107RC216CERD 10N 63V 20% RA2A3107RC217CERD 10N 63V 20% RA2A3107RC301CERD 10N 63V 20% RA2A3107RC302CERD 10N 63V 20% RA2A3107RC502PCRB 100N 100V 5% RA5mm2H410A1C303CERD 1N0 63V 20% RA2A2107RC304CERD 1N0 63V 20% RA2A2107RC305CERD 47P 63V -20% +80%RA2A0477RC306CERD 47P 63V -20% +80%RA2A0477RC401ELST 10U 50V2N6107RC402PEST 220N 63V 10%2K4227RC402PCRB 100N 100V 5% RA5mm2H410A1C403PCRB 100N 100V 5% RA5mm2H410A1C403PEST 220N 63V 10%2K4227RC404PPRO 4N7 63V 5% RA2D247N7RC4042N2 PP2D222A1C405ELST 10U 50V2N6107RC406CERD 100P 63V 20% RA2A1107RC407CERD 100P 63V 20% RA2A1107RC408CERD 10P 63V 20% RA2A0107RC501ELST 10U 50V2N6107RC502PEST 220N 63V 10%2K4227RC503PEST 220N 63V 10%2K4227RC503PCRB 100N 100V 5% RA5mm2H410A1C504PPRO 4N7 63V 5% RA2D247N7RC5042N2 PP2D222A1C505ELST 10U 50V2N6107RALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL5C506CERD 100P 63V 20% RA2A1107RC507CERD 100P 63V 20% RA2A1107RC508CERD 10P 63V 20% RA2A0107RC601PPRO 100P 63V 5% RA2D110N7RC602CERD 47P 63V 20% RA2A0477RC603ELST 22U 63V2N6227RC604PPRO 4N7 63V 5% RA2D247N7RC605PPRO 1N3 63V 5% RA2D213N7RC606ELST 10U 50V2N6107RC701PPRO 100P 63V 5% RA2D110N7RC702CERD 47P 63V 20% RA2A0477RC703ELST 22U 63V2N6227RC704PPRO 4N7 63V 5% RA2D247N7RC705PPRO 1N3 63V 5% RA2D213N7RC706ELST 10U 50V2N6107RC801PPRO 100P 63V 5% RA2D110N7RC802PPRO 100P 63V 5% RA2D110N7RC803ELST 10U 50V2N6107RC804ELST 10U 50V2N6107RC805CERD 10N 63V 20% RA2A3107RC806CERD 10N 63V 20% RA2A3107RC901CERD 10N 63V 20% RA2A3107RC902ELST 220U 16V2N7227RC903CERD 10N 63V 20% RA2A3107RC904CERD 10N 63V 20% RA2A3107RC905CERD 10N 63V 20% RA2A3107RC906CERD 10N 63V 20% RA2A3107RC907ELST 1M0 25V2N8107RC1000CERD 10N 63V 20% RA2A3107RCL1ALPHA AMP 7/8 HEATSINKCLAMPE822017RCL2ALPHA AMP 7/8 HEATSINKCLAMPE822017RD1RECTIFIER 1N4003F 1A200V3B40037RD2ZENER 10V 400MW3C110047RD3ZENER 10V 400MW3C110047RD4ZENER 10V 400MW3C110047RD5SSDIODE 1N4148 75V3A41487RD6RECTIFIER 1N4003F 1A200V3B40038RD7SSDIODE 1N4148 75V3A41487RD8RECTIFIER 1N4003F 1A200V3B40037RD9RECTIFIER 1N4003F 1A200V3B40037RD10ZENER 5V6 400MW3C056048RD101RECTIFIER 1N4003F 1A200V3B40037RD102ZENER 10V 400MW3C110047RD103ZENER 10V 400MW3C110047RD104ZENER 10V 400MW3C110047RD105RECTIFIER 1N4003F 1A200V3B40037RD106RECTIFIER 1N4003F 1A200V3B40037RD107RECTIFIER 1N4003F 1A200V3B40037RD108ZENER 5V6 400MW3C056047RD201ULTRAFAST RECTIFIERDIODE UF5403 3A3B5403F7RD202ULTRAFAST RECTIFIERDIODE UF5403 3A3B5403F7RD203ULTRAFAST RECTIFIERDIODE UF5403 3A3B5403F7RD204ULTRAFAST RECTIFIERDIODE UF5403 3A3B5403F7RD801ZENER 5V6 400MW3C056047RD802ZENER 4V7 400MW3C047047RD803SSDIODE 1N4148 75V3A41487RD901RECTIFIER 1N4003F 1A200V3B40037RD902ZENER 5V6 400MW3C056047RD903RECTIFIER 1N4003F 1A200V3B40037RD904ZENER 5V6 400MW3C056047RD905SSDIODE 1N4148 75V3A41487REL1FUSE CLIP WCK-180-01AF0627RFS201INS COVER PCBFUSEHOLDERF0227RFS201FUSE 20mm 1.25A ASC121267RFS201FUSEHOLDER 20mm PCB8S0047RFS202FUSEHOLDER 20mm PCB8S0047RFS202INS COVER PCBFUSEHOLDERF0227RHS1ALPHA AMP 7/8 HEATSINKE818017RHS1SIL PAD - 25 X 12.5mmE817MC7RHS1ALPHA AMP 7/8 HS CLIPE810MC7RHS2SIL PAD - 25 X 12.5mmE817MC7RHS2ALPHA AMP 7/8 HEATSINKE818017RHS2ALPHA AMP 7/8 HS CLIPE810MC7RHS3SIL PAD - 25 X 12.5mmE817MC7RALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL6HS3ALPHA AMP 7/8 HEATSINKE818017RHS3ALPHA AMP 7/8 HS CLIPE810MC7RHS4SIL PAD - 25 X 12.5mmE817MC7RHS4ALPHA AMP 7/8 HS CLIPE810MC7RHS4ALPHA AMP 7/8 HEATSINKE818017RL1INDUCT 2U2 12x20mm7D002B7RL101INDUCT 2U2 12x20mm7D002B7RLED201LED RED/GREEN 5MM3D0027RLK19RES MF W4 3K3 1%1H2337RLK19AA8R AMP MBD TO AVSWITCH CABLEL835CA8RLK20RES MF W4 3K3 1%1H2337RLK3117-WAY RIBBON 250mmL825CA7RLK805JUMPER 3 WAY x 125mmL815CA7RLK901JUMPER 8-WAY LEADL809CA7RLK902JUMPER 3 WAY x 125mmL815CA7RMSMAINS SWITCH SPACERE669017RPCBPRINTED CIRCUIT BOARDL846PB7RQ1TRANS PWR MOSFETIRF540/SMF0454K0457RQ2TRANS PWR MOSFETIRF540/SMF0454K0457RQ3TRANS LF SS P BC556B4A5567RQ4TRANS LF SS N BC546B4A5467RQ5TRANS LF SS P BC556B4A5567RQ6TRANS LF SS P BC556B4A5567RQ7TRANS LF SS P BC556B4A5567RQ8TRANS LF SS N BC546B4A5467RQ9TRANS LF SS N BC546B4A5467RQ10TRANS LF SS N BC547B4A5477RQ11TRANS LF SS N BC547B4A5477RQ12TRANS LF SS N BC547B4A5477RQ13TRANS LF SS N BC547B4A5477RQ14TRANS LF SS P BC557B4A5577RQ15TRANS LF SS N BC546B4A5467RQ16TRANS LF SS P BC557B4A5577RQ17TRANS LF SS N BC546B4A5467RQ18TRANS LF SS N BC546B4A5467RQ19TRANS LF SS P BC556B4A5567RQ101TRANS PWR MOSFETIRF540/SMF0454K0457RQ102TRANS PWR MOSFETIRF540/SMF0454K0457RQ103TRANS LF SS P BC556B4A5567RQ104TRANS LF SS N BC546B4A5467RQ105TRANS LF SS P BC556B4A5567RQ106TRANS LF SS P BC556B4A5567RQ107TRANS LF SS P BC556B4A5567RQ108TRANS LF SS N BC546B4A5467RQ110TRANS LF SS N BC547B4A5477RQ111TRANS LF SS N BC547B4A5477RQ112TRANS LF SS N BC547B4A5477RQ113TRANS LF SS N BC547B4A5477RQ114TRANS LF SS P BC557B4A5577RQ115TRANS LF SS N BC546B4A5467RQ116TRANS LF SS P BC557B4A5577RQ117TRANS LF SS N BC546B4A5467RQ118TRANS LF SS N BC546B4A5467RQ119TRANS LF SS N BC546B4A5467RQ120TRANS LF SS N 2SC25474A25467RPL116 WAY DIL PIN HEADER8K63168PR1ARES MO 3W 5% 0R22KOASPR31Q9227RR1RES MO 3W 5% 0R22KOASPR31Q9227RR2RES CF W2 4R7 5%1D8477RR3RES CF W4 5% 2R21B8227RR4RES MF FU W3 100R 5%NFR251G1107RR5RES MF FU W3 100R 5%NFR251G1107RR6RES MF FU W3 100R 5%NFR251G1107RR7RES MF FU W3 470R 5%NFR251G1477RR8RES MF FU W3 470R 5%NFR251G1477RR9RES MF FU W3 470R 5%NFR251G1477RR10RES MF FU W3 470R 5%NFR251G1477RR11RES MF FU W3 470R 5%NFR251G1477RR12RES MF FU W3 470R 5%NFR251G1477RR13RES MF W4 1% 1K01H2107RR14RES MF W4 1% 1K01H2107RR15RES CF W4 5% 1K01B2107RR16RES MF W4 1% 2K71H2277RR17RES MF W4 1% 5K61H2567RR18RES MF W4 1% 2K71H2277RALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUALALPHA ONE/7R/8R/8P AMPLIFIER SERVICE MANUAL7R19RES CF W4 5% 5K61B2567RR20RES MF W4 1% 15K1H3157RR21RES MF W4 1% 100R1H1107RR22RES MF W4 1% 120R1H1127RR23RES MF W4 1% 2K71H2277RR24RES MF W4 1% 2K71H2277RR25RES MF W4 1% 330R1H1337RR26RES MF FU W3 470R 5%NFR251G1477RR27RES MF FU W3 470R 5%NFR251G1477RR28RES MF W4 18K 1%1H3187RR29RES MF W4 1% 1K21H2127RR30RES MF W4 1% 33K1H3337RR31RES CF W4 5% 1K01B210A1R32RES MF W4 1% 33K1H333A1R33RES MF W4 1% 680K1H468A1R34RES MF W4 1% 1K01H2107RR34RES MF W4 1K6 1%1H216A1R35RES MF W4 1% 33K1H3337RR36RES MF FU W3 100R 5%NFR251G1107RR39RES MF W4 18K 1%1H3187RR40RES MF W4 1% 33K1H333A1R41RES MF FU W3 470R 5%NFR251G1477RR42RES MF W4 1% 620R1H1627RR43RES MF W4 1% 22K1H3228RR44RES MF W4 1% 68K1H3687RR45RES MF W4 18K 1%1H3187RR46RES MF W4 1% 150R1H1157RR47RES MF W4 1% 4K71H2477RR48RES MF W4 1% 47K1H3477RR49RES CF 1W 330R 5%1E1337RR50RES CF W2 100R 5%1D1107RR51RES MF W4 1% 15K1H3157RR52RES MF W4 1% 3K91H2397RR53RES MF W4 18K 1%1H3187RR54RES MF W4 1% 68K1H3687RR55RES MF W4 1% 22K1H3227RR56RES MF W4 1% 22K1H3227RR57RES CF 1W 2K7 5%1E2278RR58RES MF W4 1% 1K81H2187RR61RES MF W4 18K 1%1H3187RR62RES MF W4 18K 1%1H3187RR63RES MF W4 1% 56K1H3568RR64RES MF W4 1% 56K1H3568RR70RES MF W4 1% 680R1H1687RR101AR