McIntosh-C45-pre-sm 维修电路原理图.pdf

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1、SERVICE MANUALPerformance Specifications . 2 - 3Rear View and Section Location . 4Block Diagram . 5 - 8Interconnection Diagram . 9 - 10Main Schematic and PCB . 13 - 26Display Schematic and PCB . 27 - 326 Channel Schematic and PCB. 33 - 36Tone Schematic and PCB . 37 - 38Data Schematic and PCB. 39 - 4

2、0Pushbutton Schematic and PCB . 41 - 42Tuner/RAA1 Schematic and PCB . 43 - 46Tuner AM/FM Alignment Procedure. 47 - 48Parts List . 51 - 60Exploded View and Parts Lists . 61 - 65Repacking Instructions . 67CONTENTSAUDIOCONTROL CENTERSERIAL NO. XF1001 And AboveSerial Number XF1001 And AboveRadioFans.CN

3、收音机爱 好者资料库PERFORMANCE SPECIFICATIONSFrequency Response+0, -0.5dB from 20Hz to 20,000HzTotal Harmonic Distortion0.002% maximum from 20Hz to 20,000Hz at rated outputSignal To Noise RatioPhono: 86dB below 10mV input (A Weighted)High Level: 96dB below rated output (A Weighted)Rated Output Voltage2.5V Un

4、balanced Outputs (Main)5.0V Balanced Outputs (Main)Maximum Voltage Output8V Unbalanced16V BalancedOutput Impedance250 ohms Unbalanced500 ohms BalancedInput ImpedancePhono: 47k ohms, 65pfHigh Level: 22k ohms Unbalanced, 50k ohms BalancedSensitivity for Rated OutputPhono: 4.5mVHigh Level: 450mV Unbala

5、nced, 900mV BalancedMaximum Input SignalPhono: 50mVHigh Level: 5V Unbalanced, 10V BalancedVoltage GainPhono to Tape/VCR Out: 40dBPhono to Output (Main): 55dBHigh Level to Tape/VCR Out: 0dBHigh Level to Output (Main): 15dBTone ControlsBass Control: 12dB at 30HzTreble Control: 12dB at 10,000HzPower Re

6、quirements100 Volts 50/60Hz, 35 watts110 Volts 50/60Hz, 35 watts120 Volts 50/60Hz, 35 watts220 Volts 50/60Hz, 35 watts230 Volts 50/60Hz, 35 watts240 Volts 50/60Hz, 35 wattsNote: Refer to the rear panel of the C45 for the correct voltage.Overall Dimensions17-1/2 inches (44.45cm) W, 6 inches (15.24cm)

7、 H, includingfeet, 16-1/2 inches (41.91cm) D, including clearance forknobs and connectors.Weight21 pounds (9.53kg) net, 35 pounds (15.88kg) in shipping car-tonOPTIONAL TM1 TUNERFM TunerUseable Sensitivity14dBf which is 1.4uV across 75 ohms50dB Quieting SensitivityMono: 19dBf which is 2.4uV across 75

8、 ohmsStereo: 35dBf which is 15uV across 75 ohmsSignal To Noise RatioMono: 75dBStereo: 70dBFrequency ResponseMono: +0, -1dB from 20Hz to 15,000HzStereo: +0, -1dB from 20Hz to 15,000HzHarmonic DistortionMono: 0.3% at 100Hz, 0.3% at 1,000Hz, 0.3% at 10,000HzStereo: 0.45% at 100Hz, 0.45% at 1,000Hz at 1

9、000Hz, 0.65% at10,000HzIntermodulation DistortionMono: 0.25%Stereo: 0.45%Capture Ratio1.2dBAlternate Channel Selectivity75dBSpurious Response100dBImage Response75dBRF Intermodulation65dB2RadioFans.CN 收音机爱 好者资料库31. The heavy notes on the schematic denote the primarysignal path.2. Unless otherwise not

10、ed, all voltages indicated on theschematics are measured under the following conditions:a. AC input at 120 volts, 50/60Hz.b. All voltages are +/-10% with respect to ground. Ahigh impedance (10 megaohm) voltmeter must be used.3. Unless otherwise specified:a. Resistor values are in ohms.b. Capacitor v

11、alues are microfarads (uF).c. Inductor values are in microhenries (uH).4.On PC board drawings, Square pad indicates:a. Polarized Capacitors - Positiveb. Diodes - Cathodec. Others - Pin 15.WARNINGParts marked with the symbol have criticalcharacteristics. Use only replacement parts recom-mended by the

12、 manufacturer.NOTESStereo Separation45dB at 100Hz45dB at 1,000Hz35dB at 10,000HzSCA Rejection65dBAM TunerSensitivity20uV External Antenna InputSignal To Noise Ratio48dB at 30% modulation58dB at 100% modulationHarmonic Distortion0.5% maximum at 50% modulationFrequency Response50Hz to 6kHz NRSCAdjacen

13、t Channel Selectivity45dB minimum IHFImage Rejection65dB minimum from 540Hz to 1,600kHzIF Rejection80dB minimumPERFORMANCE SPECIFICATIONS contC454REAR VIEWTOP VIEW WITH COVER REMOVEDSECTION LOCATION56BLOCK DIAGRAMC4578BLOCK DIAGRAM contINTERCONNECT1910C45NOTES1112131514C45MAIN 749850 SH 1 OF 52A1618

14、17MAIN 749850 SH 2 OF 52BMAIN 749850 SH 3 OF 52C1920C45MAIN 749850 SH 4 OF 52D2122MAIN 749850 SH 5 OF 52E2324BLUBLUREDRED88888888888111115V12V33V5V0V5V0V5V0V5V5V0V5V0V5V5V5V5V5V5V0V0V0V0V0V0V0V0V5V5V5V-24V5V0V5V5V-24V0VGND5V5VSSFIL2FIL1FIL16666666666666663B3B3B3B3B3B3B3B3B3B3B3B3B3BJ8:18J8:17J8:16J8

15、:15J8:13J8:12J8:11J8:10J8:8J8:7J8:6J8:5J8:3J8:2J8:188888833V5V5V0V0V5V5V5V0V0V5VINPUT5V5VFIL25V15VNCNC5VFIL26663B3B3B3B3B3B3B3B3BJ8:14J8:9J8:4TO DATA PCBTO POWER TRANSFORMERJ3:212VJ3:333VJ3:4J3:5J5:1J5:3J5:4J4:2J4:3J4:4MPXJ4:7RED/YELSDATAPLLCESCLKTUNER_SSD5D7D10D13D95V REGULATOR12V REGULATOR15V REGU

16、LATOR-24 REGULATOR12VDRIVERINPUTDRIVER0VPOWERONTUNER_MUTE0V5VTRIGGER_B0V5V0V5V0V5V5V1WHTGRN/0VDECODERDECODERDECODERFIL2FIL1FILSCLKTRIGGER_B15V4.3V0V5V5V5V0VIR_DATA0VSCLKSQH1595CEVOLCEVOLDASDATASDATA2-24V5VPLLCEFIL2UPDATEIR MUTECONTROLPOWERONPOWERONTRIGGER BIR DATATRIGGER ASQH1595CEGNDJ1:23PRESENTJ1:

17、22VOLUMECLOCKIR MUTEJ1:19DATAJ1:18EX DATAJ1:17IR TO595 CLOCKJ1:14SDATA2J1:13VFD -24VJ1:12SCLKJ1:9J1:8PLLCEJ1:7KEYPADUPDATEMPXJ1:4J1:3J1:2NCJ3:15VGNDJ3:6GNDGNDJ5:2TO OPTIONAL TUNERJ4:1J4:5J4:6SS VOLTSMPX.047uFC172F12AF32A.047uFC17110uFC19210uFC193D8D6D14D12D1522uFC174D16D1112220kR244:A8V5V321IN OUTU2

18、2HS1231IN OUTU323300uFC178321IN OUTU24HS2-15V REGULATOR312IN OUTU251kR237D173421K345V.1uFC18310uFC186.1uFC19810uFC199.1uFC18010uFC184.1uFC182220uFC1875V0V0V5VTRIGGER_AFRONT_6CH0V5V0V11GRNGRN100kR239.1uFC188CENTER10uFC190220pFC1915.9 VACFIL1595CETRIGGER_A0V5VVOLCK595CEIR_DATASCLKMPXFIL1KEYPADEXT DATA

19、GNDSCLKTUNERVOLUME CEJ1:20J1:21VOLUMESDATAJ1:15J1:16J1:10J1:11J1:5J1:6J1:11GP2F22A34220kR244:B3300uFC179231IN OUTU233421K35.1uFC18110uFC185POWER TRANSFORMER.1uFC189TO DISPLAYJ23:4J23:3PLL DATARIGHTLEFTJ22:1TUNSCLKJ21:5MUTETUNER_MUTE15VJ18J17J1608/06/02 res129466 0498506CH_SELP1169 C45 MAIN (PS)6CH2_

20、CONTROL6CH1_CONTROL5VR_2CHL_2CH2CH_SUBBAL_CONTROL_6CHBAL_CONTROL_2CHTONE_BYPASSTAPE1_OUTTAPE_CONTROLSAT_CONTROLDVD_CONTROLCD_CONTROLPH/AUX_CONTROL15V-15VSQH15V1kR240SDATA2J7:2J7:3J7:7J7:8POWERONJ7:12J7:13J7:17J7:18J6:1TUNER_PRESENTEXT SENSORJ6:6DATA PORTSJ6:11SCAN STOPJ6:16SCAN_STOPJ6:21J23:6J23:2J2

21、3:1J22:3J22:2J22:4JMP1PRESENTPLL CEJ21:6J21:4J21:7TUNER_PRESENTSCAN STOPJ21:1J21:2SCAN_STOPJ20J1947uFC173470uFC17647uFC175rev 05/21/03 resSUB_MUTE2CH_CONTROL6CH_CTL5V5VTAPE2_OUTINT_TU_CONTROLPH/AUX_SELVCR_CONTROLCD2_CONTROLTU_CONTROL-24V1kR241IRMUTEJ14J15F40.4AD3J7:4J7:5J7:10J7:91kR243J7:15J7:14J6:4

22、J6:3J6:2J6:5J6:9J6:8J6:7J6:10J6:14J6:12J6:13J6:15TUNER_SSJ6:19J6:18J6:17J6:20J6:23J6:22J23:53300uFC177J21:3678912345141516171810111213GNDU26678912345141516171810111213GNDU27678912345141516171810111213GNDU2863112111075421514913QFQGQDQAQBOEQHQCQELCLKSQHRESETSCLKDATAU3163112111075421514913QFQGQDQAQBOEQ

23、HQCQELCLKSQHRESETSCLKDATAU2963112111075421514913QFQGQDQAQBOEQHQCQELCLKSQHRESETSCLKDATAU304.99kR245J12J7:1J7:61kR242J7:11J7:16INT_TU_CONTROLT1T1T1T1T1-38V-22V22VC452526MAIN 749850 PCB2DISPLAY 749851 SH 1 OF 23A2728C452930DISPLAY 749851 SH 2 OF 23BJ6:2J6:3J6:4J6:7J6:8J6:92E2E2E2E2E2E2E2E2E2E2E2E2E2ESS

24、5V5V5V0V0V5V5V0V5V5V5V5V5V0V5V0VGNDGND5VC1C0R1R0R07777777TO MAINJ6:1J6:5J6:62E2E2E2E2E2E2E2E2E0V5V0V5V5V5V5V0V5V10R4TRIM5V5V0VR2R377777TO PUSHBUTTONJ6:12J6:13J6:14J6:17J6:18J6:19J6:22J6:23TUNER_SS0VSCLKLAMP_ONSDASCLMPX5VWDT5V0V5VLAMP_ON0V.1uFC115V0V.1uFC85V5V5V5V5V5V0V5V5V0V5VENTERTONE5VIR_EXT0VINPU

25、T129467CONVERTED DATA0498515V5V5V5V5VIR_FP5VFRONT0V0V5V5VJ3:7J3:4J3:2J3:1J3:10J3:8J3:6J6:10J6:11J6:16J6:15J6:21J6:20-24V5V10R810uFC9312Q1ADCE5VDS55VFIL210R1210uFC12IR_FPWDTADCESCLKDS7DS85V100kR260V220pFC141kR1610kR35V5V132Y112.0MHz10kR75V0V0V0V5V5VCONTROLLERDS105V5V5V5V0V0V5V5VSTANDBY/ONSETUPBYPASSI

26、R_FP0VSELECT5V1098U4:C0V5V546U4:B1098U8:CFRONTPANEL IRPANEL IR0V5V5VJ3:9J3:3J3:11J3:12J3:5100R18100R20100R21100R1910uFC157RST6SCL8VCC5SDA2RST3WP1WDI4GNDU2DS3131211U8:DSDATATUNER_PRESENTCLOCKJ1:21VOLCKIR MUTEIRMUTEVOLUME CEVOLUMEIR_EXTIR_EXTDATA PORTSJ1:16IR_DATAVOLCEVOLDA595 CLOCK595CEIRMUTESDATASDA

27、TA-24V595CESCLKJ1:11SCLKPLLCETUNER_SS.6VPLLCEUPDATEJ1:6KEYPAD_UPDATEMPXD4MPXFIL2FIL1J1:1FIL1324R17595CESDATAMTGPAD3MTGPAD2SCLSDAMICROPROCESSORILLUMINATION08/28/02 resP1169 C45 Display 2 of 2VFDAVFCE.1uFC10IR_DATAJ2:11J2:5SIGNAL STRENGTHA/D CONVERTER.1uFC13TUNERVOLUMEPRESENTGNDJ1:23J1:22EXT SENSOREX

28、DATADATAIR TOJ1:18J1:19J1:17VOLDAVOLCEVOLCKSDATA2VFD -24VJ1:13J1:14J1:12SDATA2SDATASCAN_STOPPLLCEKEYPADSCAN STOPJ1:8J1:9J1:72.21kR25DS6SCAN_STOPFIL2FIL1J1:4J1:3J1:2100R133421K1324R23324R24SDATA2324R14SCLK5VMTGPAD1234567891R108x22k47uFC7DS9FRONT PANELWATCHDOG TIMER / RESETrev 05/13/03 resDS4DS11DS221

29、3U4:ADATA PORT CONTROLTUNER_PRESENTVFCLJ2:9J2:4J2:10J2:6KEYPAD_UPDATEJ2:12J2:1J2:3J2:2J2:7J2:8J1:2087651234OUTCLKI/O-+VccGNDREFINALGREFDATACSU6TREBLEBASSTONEJ3J1:15J1:10J1:5324R1563112111075421514913QFQGQDQAQBOEQHQCQELCLKSQHRESETSCLKDATAU5100R22234567891R68x22k66553VOL_B15V4GND2VOL_AVOLUMECONTROLS22

30、13U8:A546U8:B234567891R58x10k131211U4:D20VSS40VDD21P2.019XT123P2.224P2.317P3.716P3.626P2.514P3.428P2.729PSE12P3.211P3.131EA9RST33P0.67P1.634P0.56P1.536P0.34P1.338P0.12P1.139P0.01P1.022P2.125P2.415P3.518XTO27P2.630ALE32P0.735P0.45P1.48P1.710P3.013P3.337P0.23P1.2U33124 5CCWCWS123451R274x22kDISPLAY 749

31、851 PCB33132C4533346 CHANNEL 749852 SCH4RSLSRFLFLSSUBRFLF5V5V5V5V1LSGNDSUBGNDGNDGNDGNDLF2A2A2A2A2A2A2A2A2AJ1:5J1:6J1:7J1:8J1:9J1:10J1:16J1:17J1:18RF0V0V0V0V0V0V0V0V0V0VRS0V0V0V-15V0V0V0V0V0V0V0VLS-15vLF-2B2B2B2B2B2B2B2B2B2B2BJ10:5J10:4J10:3J10:2J10:1SUBRS5V5V25VRSGNDGNDRF2A2A2A2A2A2A2A2A2AJ1:4J1:3J1

32、:2J1:1J1:13J1:12J1:11J1:15J1:14TO MAINRSLSSUBLF231S-+J9231S-+J80V0V0V0V0V0V0V10uFC2410uFC2310uFC22LFLS15V-15V0V0V5V5V0V0V0V2B2B2B2B2B2B2BJ10:9J10:7J10:810:6231S-+J7231S-+J6231S-+J11231S-+J5231S-+J1210uFC21D1100kR30TO MAIN231S-+J106 CHANNEL 2INPUTS6 CHANNEL 10V0V0V0V0V0V0V0V0V5V5V5V5V25VFRONT 2 2CHFR

33、ONT 1 2CH5V5V5VSUB_MUTE0V0V0V0V6CH IN 26CH IN 1FRONT6CHCENTERCENTER5V221R12221R115V5VSUB_MUTE20KR35- BALANCED AMP0VCENTER20KR310V0V0V0V0V0V0V0V-15V15V2 CH6 CHLS+-15vSUB+GNDBRF+LF+J10:17J10:16J10:15J10:14J10:13J10:1210uFC1110uFC126J2:D5J2:C10uFC910uFC103J2:B2J2:A0V0V10uFC710uFC811J1:G12J1:H0V10uFC56J

34、1:D8J1:E10uFC310uFC23J1:B12220kR6:A34220kR6:B12220kR5:A12220kR3:A34220kR3:B12220kR2:A34220kR2:B34220kR1:B12220kR1:A3421K66CH23421K53421K46CH13421K12D35V3421K113421K10D23421K83421K75V15VDRIVERDRIVER10kR4310kR455V6CH16CH25V0V0VSUB MUTE33.2kR24221R17221R1833.2kR23221R1633.2kR22221R13221R46221R44221R922

35、1R10221R49221R47221R8221R73421K183421K17D5D422uFC30100kR2922uFC29100kR2822uFC2622uFC2722uFC25- BALANCED AMP- BALANCED AMP20KR34SUB20KR32- BALANCED AMP20KR33RF0V0V.1uFC310V0V0V.1uFC34.1uFC35.1uFC36GNDRS-FRONTSELECTRS+CENTER-SUB-CENTER+RF-J10:18J10:10J10:1110uFC69J1:F10uFC410uFC15J1:C2J1:A34220kR5:B34

36、220kR4:B12220kR4:A3421K33421K23421K13421K933.2kR21221R14221R1533.2kR1933.2kR203421K153421K133421K14100kR2622uFC28100kR25100kR27CENTER5V5V5V- BALANCED AMP20KR4215V20KR40J4:5J4:6J4:16J4:1720KR39CENTER5V25V110uFC19OUTPUTS10uFC1810uFC1710uFC3810uFC3710uFC1610uFC1510uFC4010uFC3910uFC1410uFC1320KR36657-+U

37、3:B231-+U3:A- BALANCED AMP20KR41J4:1J4:3J4:4.1uFC32J4:7J4:8J4:9J4:10-15VJ4:11J4:12J4:13J4:1415VJ4:18.1uFC33132Q2132Q110uFC203421K16657-+U2:B231-+U2:A231-+U1:A657-+U1:B20KR38J4:2J4:1520KR37J3:12J3:2J3:1J3:18J3:15J3:17J3:16J3:11J3:13J3:8J3:9J3:7J3:4J3:5J3:3J3:14J3:10J3:66 CHANNEL 749852 PCB43536C45373

38、8TONE 749853 SCH and PCB50V0V0V5V5V0V2B2B2B2B2BJ11:90V0V5V47uFC1047uFC110V0V2B2BBASS0V.1uFC2615V.1uFC25-15VTREBLE40.2kR140V3.32kR170V-15V0V0V5V0VBYPASSJ11:13R TOJ11:14GNDJ11:17J11:18R FROMJ11:102B15V5V2BJ11:8J11:112BGND2BJ11:1L TO2BJ11:2L TOGNDJ11:52BJ11:62BL FROM22uFC1.033uFC322uFC23412CCWR6:A100k7

39、856CCWR6:B100k3421K45V475R73421K1475R83421K3475kR11475kR1240.2kR13.22uFC13.22uFC14470pFC160V657-+U1:B100pFC170V100pFC183.32kR1815V0V10uFC2410uFC2310R2310R240VR TOJ11:15GNDJ11:16R FROM2BJ11:12-15VJ11:72BGNDJ11:32BJ11:42BGNDL FROMTO MAIN3421K2475kR10475kR9470pFC15231-+U1:A681R3J1:10J1:5J1:1J1:18J1:136

40、81R23412CCWR1:A100k765-+U2:B.033uFC4100kR57856CCWR1:B100k47uFC12.033uFC5.22uFC747uFC9.033uFC6.22uFC8100kR16J1:63.32kR20J1:310R19J1:2.1uFC22.1uFC21J1:7J1:11J1:123.32kR22J1:8J1:16J1:1510R21J1:14100kR4123-+U2:A100kR15J1:4J1:9J1:17DATA 749854 SCH and PCB63940C454142PUSHBUTTON 749855 SCH and PCB7J13:2J13

41、:30V0V0V5VC0R3R2R1R033333333J2:6J2:4J2:10J2:12J2:2J2:1J2:7J2:8TO MAINJ13:1TRIM5VC1R03333J2:9J2:3J2:11J2:5TO DISPLAYGND2CL HDPH2CTUNES5TRIMLEVELTUNES6TRIMS80V5V0V0V5V5V5VHDPHR HDPH2C100pFC3STANDBY/ONS1MUTELEVELS2S4.1uFC15V100R15V5VENTERS7MODEIR SENSORGNDJ3:9PANEL IRPANEL IRFRONTJ3:11J3:5132J2SET UPS3

42、47uFC2GNDFRONTJ3:3J3:7J3:1J3:12J3:2J3:6J3:8J3:10J3:4213VccVoutGNDMT1J1:2TONE BYPASSJ1:1J1:3HEADPHONESTUNER 049084 SCH84344C454546TUNER 049084 PCB8RAA1 SECTION9Rev. BTUNER ALIGNMENT PROCEDURE4748Note: Refer to Figure 1 while reading the below procedure.C45 Tuner: FM ALIGNMENT PROCEDURE1.Connect an FM

43、 Signal Generator to Antenna Input.2.Connect Distortion Analyzer to the TUNER IN/OUT RCAjacks.3.Remove Top Cover and AM/FM TUNER Cover. Turn On theAC rocker switch. Press the red Standby button to turn theunit On.4.Select Tuner with the Zone A selector knob. Put Tuner intoFM mode and tune to 87.5MHz

44、.5.Adjust L5 (FM OSC Coil) for 3.5VDC at R46.6.Tune to 108.5MHz and adjust C59 (FM OSC TrimmerCapacitor) for 24.5VDC at R46.7.Repeat steps 4, 5 and 6 as necessary for a tuning range of3.5VDC to 24.5VDC at R46.8.Tune the Generator and Tuner to 90MHz and adjust Coils:L2 (FM MIX), L3 (FM RF) and L4 (FM

45、 ANT) for best sensi-tivity.9.Tune the Generator and Tuner to 104MHz and adjustTrimmer Capacitors: C60 (FM MIX), C62 (FM RF) and C63(FM ANT) for best sensitivity.10. Repeat 8 and 9 until no improvement in sensitivity is noted.11. Tune Tuner to 90MHz with no RF Input and adjust T9 (FMDETector Primary

46、) for zero volts between TP1 and TP2relative (connector J6).12. Tune the Generator to 90MHz and adjust the RF Output to1000uV and 100% MONO modulation at 1000Hz. Thenadjust T8 (FM DETector SECondary) for lowest distortion.13. Reduce the Generator Output to minimum and detune theGenerator so the Rece

47、iver picks up only noise, thenrecheck the voltage between TP1 and TP2 (connector J6).Adjust T8 and C65 if needed.If it is not 0+/- 0.2VDC, repeat steps 11 and 12. If there isinterference from a station on this frequency, tune the Tunerto a nearby frequency free from interference for this mea-suremen

48、t.14. Tune the Generator to 90MHz with a 1000uV output. Thenswitch the Generator to stereo (left only) and adjust T10(FM IF Transformer) for the lowest distortion at the TUNERIN/OUT RCA jacks.15. Switch the Analyzer to the right channel TUNER IN/OUTjack and adjust R71 (MPX SEParation Pot) for best s

49、epara-tion (minimum output).16. Switch the Generator to the Right Channel and the Ana-lyzer to the Left Channel. Adjust R71 (MPX SEParationPot) and check for best separation (minimum output).17. Disconnect voltmeter from TP1 and TP2 (J6). Reduce thegenerator output to 5uV and adjust R73 (STEREO SWIT

50、CHPot) so the MPX light (Dot next to Signal Strength number)just comes on.C45 Tuner: AM ALIGNMENT PROCEDURE1.Connect an AM Signal Generator to the RAA1 ”EXT ANT”pin of the 5 pin connector. Connect a Distortion Analyzer tothe C45 rear panel TUNER IN/OUT RCA jacks.2.Tune to bottom of band, and adjust