Audiolab-8000S-int-sm维修电路原理图.pdf

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1、?RadioFans.CN 收音机爱 好者资料库introductionNo part of this document may be reproduced or transmitted in any form or by any means,electronic or mechanical, for any purpose, without the express written permission of International Audio Group Limited (IAG).This manual is for the exclusive use of IAG, its appr

2、oved distributors and approved UK service agents. No part of this manual shall be transferred to a third party without the written permission of IAG.It is the responsibility of the user to ensure that all the information contained in this manualis current. Notification for new issues of this manual

3、and minor updates will be given viathe IAG web-site or on request.This manual has been prepared with the greatest care, it is intended for information onlyand no liability shall be accepted for errors or changes to specification.For further service information, parts lists and updates, please contac

4、t our web-site. 2005 International Audio Group Limited. All rights reserved.Notification for new issues of this service manual will be given via the Audiolab web site:- issue number :- 2005/001/8000SG GR RP P0 00 00 00 03 3. .0011issue date :- September 04 20052 2 5 5 . . 0 0 1 1 . . 1 1 9 9 92 2 5

5、5 . . 0 0 1 1 . . 1 1 9 9 9 99999RadioFans.CN 收音机爱 好者资料库index1.0safety and servicing notes1.1Safety precautions.11.2Electrostatic discharge precautions .11.3Soldering.12.0front and rear panel layouts2.1Front panel controls .32.2Rear panel connections.33.0disassembly instructionsdisassembly instructi

6、onsPages 4 and 5 DELETED4.0functional tests4.1Test equipment required .64.2Functional test procedure.75.0performance tests5.1Test equipment required .115.2Performance test procedure .126.0test points6.1Functional and performance test points .167.0circuit schematics7.1Master schematic diagram (SCH267

7、M-01-05).177.2Line amplifier left channel schematic (SCH26701-07-02) .187.3 Line amplifier right channel schematic (SCH26701-08-02).197.4Power amplifier left channel schematic (SCH26701-09-02).207.5Power amplifier right channel schematic (SCH26701-10-02).217.6Power supplies schematic (SCH26701-01-02

8、) .227.7Protect and turn on schematic (SCH26701-06-02) .237.8Digital system controller schematic (SCH26701-02-01).247.9Digital system interface schematic (SCH26701-03-01).257.10Input interface schematic (SCH26701-04-04) .267.11Relay coils schematic (SCH26701-05-01) .277.12Front panel schematic (SCH2

9、6702-01-01) .287.13Speaker outputs schematic (SCH26703-01-01).298.0printed circuit board layout8.1Printed circuit board layout (top view).308.2 Printed circuit board layout (bottom view).319.0technical data9.1 8000S Technical specifications.329.2International standards.34 11.0 safety and servicing n

10、otes1.1Safety precautions1.This unit is Class II, which means that it is not connected to the protective earth system.All live voltages are insulated from the case by double insulation. 2.Do not attempt to service unless qualified to do so.3.Disconnect unit from AC power supply before removing cover

11、.4.Components marked with the symbol on the circuit schematic are safety critical and must only be replaced with an identical component, or an alternative approved bythe manufacturer.5.Switch unit off, and disconnect from supply before making and breaking anyconnections.6.Do not adjust any controls

12、unless instructed to do so in this manual.1.2Electrostatic discharge precautionsElectrostatic discharge (ESD) is due to charges produced by insulating materials rubbing together.Humans collect electrostatic charge through normal activities when clothes rub together and whenwalking on carpet. This ch

13、arge may be discharged suddenly when you touch a conductor. If theconductor is connected to a sensitive electronic circuit, you may damage the components. It is alsopossible to reduce the life of components without causing any obvious damage.To prevent ESD damage, it is necessary to follow these gui

14、delines.1.Prepare work area. Place an ESD protective mat on the bench, strapped to theprotective earth circuit.2.Prepare yourself. Put on an ESD protective wrist band, strapped to the protective earthcircuit, or to the ESD protective mat.3.Keep all PCBs removed from unit in ESD protective bags.4.Kee

15、p all replacement electronic components, PCBs and stock items in ESD protectivebags or boxes.5.Be particularly careful with components marked with the following symbol:1.3SolderingHow to de-solder componentsComponents should be removed, wherever possible, using a de-soldering tool. Be careful not to

16、damage tracks and pads by applying too much pressure.How to make good solder joints1.Ensure surfaces are clean.2.Keep soldering iron clean and wetted with solder. Use an appropriate bit. Do not leavesoldering iron on when not in use. 21.0 safety and servicing notes3.Apply soldering iron to both comp

17、onent lead and padbefore applying solder. Make sure that the solderingiron is applied long enough for the solder to wetproperly, but do not apply for too long or componentdamage may occur.4.Allow a small gap between component body andpad. Solder must not reach the base of thecomponent.How to detect

18、acceptable joints1.Solder joints should have from a shiny to satin lustreand a generally smooth appearance.2.Solder should have wetted both the component leadand pad.3.There should be a concave meniscus between theobjects being soldered. The angle of solder to padshould be less than 90 unless the so

19、lder joint extendsover the edge of the pad.4.Solder should fill the component pad and wetcomponent lead around the full circumference (360).How to detect unacceptable joints1.Poor wetting produces a bead of solder. The fillet willbe convex instead of concave, and there will not be afeather edge.2.On

20、 double-sided PCBs, solder should wet all roundplated-through hole, on both sides of the PCB.Cleaning up after soldering1.Flux is very corrosive. Remove with IPA (propan-2-ol) before completing the job. 2.Remove any solder balls and splashes from the unit.3.Check all new solder joints and ensure all

21、 PCBs are clean before replacing covers.4.After replacing covers, clean the case and any display windows with a damp cloth. Donot use any organic solvents. If scratched, replace display windows.Trim Line? ? ? ? ? ? 64.0 functional testsThese notes are provided to assist you in servicing the amplifie

22、r. The circuit schematics are markedwith typical voltage levels, which may assist in defining the cause of any problem.4.1Test equipment requiredEquipmentDigital MultimeterDual Tracking DC PowerSupplyVarious LeadsSpecificationAccuracy better than 0.5% in V and mV rangesOutput: 32 V DC 2 APositive te

23、rminal of negative supply must be connected tonegative terminal of the positive supply unless internally linkedVmAVmA-ve+ve-ve+veSelect Tracking0 V+32 V-32 VBlack= -veRed= +veGreen = 0 VFigure 4.1 - Functional test set-up 74.0 functional tests4.2Functional test procedureFor test point (TP) reference

24、s, see section 6.0 Test Points.No4.2.1.4.2.2.4.2.3.4.2.4.4.2.5.4.2.6.4.2.7.4.2.8.4.2.9.ActionDisconnect allcables fromamplifierCheck voltagesettingCheck fusetypeCheck fuseresistanceSet up powersupplyRemove coverConnectsupplies asshown inFigure 4.1Apply DCvoltage toamplifierMeasure leftchannel supply

25、railsTest EquipmentMultimeter set to Dual tracking DCpower supplyDual tracking DCpower supplyDual tracking DCpower supplyMultimeter set to V DCDetailsRead ratings label on rear of amplifier.Open fuse holder in power socket on rearpanel.Rated supplyFuse Type230 V AC T2.5A L250V115 V AC T4A 125V110 V

26、ACT4A 125VFuse and spare fuse should be lowresistance.Set output voltage to 32 V, current limitedto 500 mA.With supplies off, connect positive output of supply to positive terminal of reservoir capacitornegative output of supply to negative terminal of capacitorNo connection is required to 0 V termi

27、nal of power supply.CAUTION:Do not connect with wrong polarity.Check supply outputs are 32 V andswitch output on.Current output should be300 mA negative supply and 600 mA positive supply.If higher, turn RV701 (TP 24) and RV801(TP 25) fully anti-clockwise. Continue with test procedure of currentoutpu

28、t is 180 mA 25 mA negative supplyand 515 mA 25 mA positive supply. If higher, switch off and investigate.Measure voltage across D713 (TP 1+ andTP 1-) and D714 (TP 2+ and TP 2-).Voltage should be 32 V 0.25 V. 84.0 functional testsNo4.2.10.4.2.11.4.2.12.4.2.13.4.2.14.4.2.15.4.2.16.4.2.17.ActionMeasure

29、 rightchannel supplyrailsCheckpreamplifiersupply railsLeft channelCheck poweramplifierLeft channelMeasureamplifier offsetLeft channel MeasurepreamplifierRight channelCheck poweramplifierRight channelMeasureamplifier offsetRight channel Measurepreamplifier Test EquipmentMultimeter set to V DCMultimet

30、er set to V DCMultimeter set to V DCMultimeter set tomV DCMultimeter set to V DCMultimeter set to V DCMultimeter set tomV DCMultimeter set to V DCDetailsMeasure voltage across D813 (TP 3+ andTP 3-) and D814 (TP 4+ and TP 4-).Volatge should be 32 V 0.25 V.Connect negative probe to 0 V (TP 0).Connect

31、positive probe to 30 V test point (TP 19).Voltage should be 28 V 3 V.Connect positive probe to 10 V test point (TP 15).Voltage should be 10 V 0.3 V.Connect positive probe to 5 V test point (TP 16).Voltage should be 5 V 0.3 V.Measure voltage across R731 (TP 5+ and TP 5-).Voltage should be 0.85 V 0.1

32、V.Measure voltage across R735 (TP 6+ and TP 6-).Voltage should be 0.85 V 0.1 V. Connect negative probe to 0 V (TP 0).Connect positive probe to R749 (TP 9).Voltage should be 5 mV.Connect positive probe to R518 (TP 12).Voltage should be 14 V 1 V.Measure voltage across R831 (TP 7+ and TP 7-).Voltage sh

33、ould be 0.85 V 0.1 V.Measure voltage across R835 (TP 8+ and TP 8-).Voltage should be 0.85 V 0.1 V. Connect negative probe to 0 V (TP 0).Connect positive probe to R849 (TP 10).Voltage should be 5 mV.Connect positive probe to R618 (TP 13).Voltage should be 14 V 1 V.4.2Functional test procedureFor test

34、 point (TP) references, see section 6.0 Test Points. 94.0 functional tests4.2Functional test procedureFor test point (TP) references, see section 6.0 Test Points.No4.2.18.4.2.19.4.2.20.4.2.21.4.2.22.4.2.23.4.2.24.4.2.25.4.2.26.ActionMeasure offsetof protectioncircuitDisconnect DCpower suppliesFix an

35、y faultsConnectamplifier to ACpower inputMeasure leftchannel supplyrailsMeasure rightchannel supplyrailsCheckoperation ofmute relayCheckpreamplifiersupply railsLeft channelCheck poweramplifierTest EquipmentMultimeter set to mV DCMultimeter set to V DCMultimeter set to V DCMultimeter set to V DCMulti

36、meter set to V DCMultimeter set to V DCDetailsConnect positive probe to cathode of D943(TP 11).Voltage should be 5 mV.If any faults have been detected, repair andreturn to the beginning of this testprocedure.Measure volatge across D713 (TP 1+ andTP 1-) and D714 (TP 2+ and TP 2-).Volatge should be 44

37、 V 2.5 V.Measure volatge across D813 (TP 3+ andTP 3-) and D814 (TP 4+ and TP 4-).Volatge should be 44 V 2.5 V.Connect negative probe to 0 V (TP 0).Connect positive probe to cathode of D951(TP 23).Switch on AC power button.Voltage should increase slowly from 0 to12 V then relay should operate and vol

38、tageshould increase to 41 V 2 V.Connect negative probe to 0 V (TP 0).Connect positive probe to 30 V test point(TP 19). Voltage should be 28 V 3 V.Connect positive probe to 10 V test point(TP 15).Voltage should be 10 V 0.5 V.Connect positive probe to 5 V test point (TP 16).Voltage should be 5 V 0.3 V

39、.Measure voltage across R731 (TP 5+ and TP 5-).Voltage should be 0.85 V 0.1 V.Measure voltage across R735 (TP 6+ and TP 6-).Voltage should be 0.85 V 0.1 V. 104.0 functional tests4.2Functional test procedureFor test point (TP) references, see section 6.0 Test Points.No4.2.27.4.2.28.4.2.29.4.2.30.4.2.

40、31.4.2.32.4.2.33.4.2.34.4.2.35.4.2.36.4.2.37.ActionLeft channelMeasureamplifier offsetLeft channelMeasurepreamplifier Right channelCheck poweramplifierRight channelMeasureamplifier offsetRight channelMeasurepreamplifier Measure offsetof protectioncircuitFix any faultsAllow amplifierto warm upLeft ch

41、annelCheck biasRight channelCheck biasReadjust biasTest EquipmentMultimeter set to mV DCMultimeter set to V DCMultimeter set to V DCMultimeter set to V DCMultimeter set to V DCMultimeter set to mV DCMultimeter set to V DCMultimeter set to V DCDetailsConnect negative probe to 0 V (TP 0).Connect posit

42、ive probe to R749 (TP 9).Voltage should be 5 mV.Connect positive probe to R518 (TP 12).Voltage should be 14 V 1 V.Measure voltage across R831 (TP 7+ andTP 7-)Voltage should be 0.85 V 0.1 V.Measure voltage across R835 (TP 8+ andTP 8-)Voltage should be 0.85 V 0.1 V. Connect negative probe to 0 V (TP 0

43、).Connect positive probe to R849 (TP 10).Voltage should be 5 mV.Connect positive probe to R618 (TP 13).Voltage should be 14 V 1 V.Connect positive probe to cathode of D943(TP 11).Voltage should be 5 mV.If any faults have been detected, repair andreturn to the beginning of this testprocedure .Leave o

44、n for 20 minutes with cover on. It isnot necessary to screw cover down.Connect probes across legs of R748 (TP 1- and TP 2-).Voltage should be 22 mV 0.5 mV.If necessary, adjust RV701 (TP 24).Connect multimeter probes across legs ofR848 (TP 3- and TP 4-).Voltage should be 22 mV 0.5 mV.If necessary, ad

45、just RV801 (TP 25).Leave on for a further 10 minutes.Repeat 4.2.35 and 4.2.36. 115.0 performance tests5.1. Test equipment requiredSpecificationAccuracy better than 0.5% in V and mV rangesAble to measuredistortion to 0.001% with 200Hz high pass filter signal to noise ratio greater than 95 dB with IHF

46、 A-weighted filter20 MHz, dual channel8 (125 W) and short circuit2 offEquipmentTrue RMS multimeterAudio analyserOscilloscopeOutput loadsShorted phono plugsVarious leadsFigure 5.1 Performance test set-up. Connections for left channel shown, repeat connections for right channel.+ 8 LoadAC Power InputO

47、scilloscopeAudio analyserOutputInputCh 1Ch 2CD I/PScope Probe 125.0 performance testsNo5.2.1.5.2.2.5.2.3.5.2.4.5.2.5.5.2.6.5.2.7.5.2.8.5.2.9.ActionSwitch off ACpower buttonConnectamplifier asshown inFigure 5.1Switch on ACpower buttonAdjust volumeknob tomaximumMeasure outputof preamplifierMeasure out

48、putof poweramplifierReduceVOLUMEknob tominimumSet OUTPUTto 20 V rmsMeasuredistortion at 1 kHzTest EquipmentAudio Analyseroutput connected toboth left and rightCD inputs8 loadAudio Analyseroutput: 1kHz, 100 mV rmsMultimeter set to mV ACAudio Analyseroutput: 1kHz, 100 mV rms200Hz HP filter onA-weighte

49、d filter offAudio Analyseroutput: 1kHz, 1 V rms 200Hz HP filter onA-weighted filter offAudio Analyseroutput 1kHz, 1 V rms 200Hz HP filter onA-weighted filter offDetailsOutput frequency:1 kHz sine waveOutput voltage:100 mV rms Reading settings:AC level, Auto, 200 Hz HP filter on A-weighted filter off

50、Select cd using INPUT selector knob.Select pre using MODE selector knob. Measure output of left and right PREAMP sockets.Voltage should be 286 mV rms 10 mV rms.Select integrated using MODE selectorknob.Measure output of left and rightloudspeaker terminals.Voltage should be 8 V rms 0.2 V rms.Increase