Lexicon-MC12-prc-sm 维修电路原理图.pdf

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1、MC-12 / MC-12 BalancedMusic and CinemaProcessorsServiceManualRadioFans.CN 收音机爱 好者资料库MC-12 / MC-12 Balanced Service ManualPrecautionsSave these instructions for later use.Follow all instructions and warnings marked on the unit.Always use with the correct line voltage. Refer to the manufacturers opera

2、ting instructions for power requirements. Be advised thatdifferent operating voltages may require the use of a different line cord and/or attachment plug.Do not install the unit in an unventilated rack, or directly above heat producing equipment such as power amplifiers. Observe themaximum ambient o

3、perating temperature listed in the product specification.Slots and openings on the case are provided for ventilation; to ensure reliable operation and prevent it from overheating, theseopenings must not be blocked or covered. Never push objects of any kind through any of the ventilation slots. Never

4、 spill a liquid ofany kind on the unit.This product is equipped with a 3-wire grounding type plug. This is a safety feature and should not be defeated.Never attach audio power amplifier outputs directly to any of the units connectors.To prevent shock or fire hazard, do not expose the unit to rain or

5、 moisture, or operate it where it will be exposed to water.Do not attempt to operate the unit if it has been dropped, damaged, exposed to liquids, or if it exhibits a distinct change in performanceindicating the need for service.This unit should only be opened by qualified service personnel. Removin

6、g covers will expose you to hazardous voltages. This triangle, which appears on your component, alerts you to the presence of uninsulated, dangerous voltage inside theenclosure voltage that may be sufficient to constitute a risk of shock.CAUTIONRISK OF ELECTRIC SHOCKDO NOT OPEN This triangle, which

7、appears on your component, alerts you to important operating and maintenance Instructions in thisaccompanying literature.NoticeThis equipment generates and uses radio frequency energy and if not installed and used properly, that is, in strict accordance with themanufacturers instructions, may cause

8、interference to radio and television reception. It has been type tested and found to comply withthe limits for a Class B computing device in accordance with the specifications of Part 15 of FCC Rules, which are designated toprovide reasonable protection against such interference in a residential ins

9、tallation. However, there is no guarantee that interferencewill not occur in a particular installation. If this equipment does cause interference to radio or television reception, which can bedetermined by turning the equipment OFF and ON, the user is encouraged to try to correct the interference by

10、 one or more of thefollowing measures:Reorient the receiving antennaRelocate the computer with respect to the receiverMove the computer away from the receiverPlug the computer into a different outlet so that the computer and receiver are on different branch circuits.If necessary, the user should con

11、sult the dealer or an experienced radio/television technician for additional suggestions. The user mayfind the following booklet prepared by the Federal Communications Commission helpful:“How to identify and Resolve Radio/TV Interference ProblemsThis booklet is available from the U.S. Government Pri

12、nting Office, Washington, DC 20402, Stock No. 004-000-00345-4.Le prsent appareil numrique nmet pas de bruits radiolectriques dpassant les limites applicables aux appareils numriques de Iaclass B prescrites dans le Rglement sur le brouillage radiolectrique dict par le ministre des Communications du C

13、anada.Copyright 2002 Lexicon, Inc.All Rights ReservedLexicon Inc. 3 Oak Park Bedford, MA 01730-1441 Tel (781) 280-0300 Customer Service Fax (781) 280-0499Lexicon Part # 070-14828 Rev 0Printed in the United States of AmericaRadioFans.CN 收音机爱 好者资料库LexiconSafety SuggestionsRead Instructions Read all sa

14、fety and operatinginstructions before operating the unit.Retain Instructions Keep the safety andoperating instructions for future reference.Heed Warnings Adhere to all warnings on theunit and in the operating instructions.Follow Instructions Follow operating and useinstructions.Heat Keep the unit aw

15、ay from heat sources suchas radiators, heat registers, stoves, etc., includingamplifiers which produce heat.Ventilation Make sure that the location orposition of the unit does not interfere with itsproper ventilation. For example, the unit shouldnot be situated on a bed, sofa, rug, or similarsurface

16、 that may block the ventilation openings;or, placed in a cabinet which impedes the flow ofair through the ventilation openings.Wall or Ceiling Mounting Do not mount the unitto a wall or ceiling except as recommended bythe manufacturer.Power Sources Connect the unit only to a powersupply of the type

17、described in the operatinginstructions, or as marked on the unit.Grounding or Polarization* Take precautionsnot to defeat the grounding or polarization of theunits power cord.*Not applicable in Canada.Power Cord Protection Route power supplycords so that they are not likely to be walked onor pinched

18、 by items placed on or against them,paying particular attention to cords at plugs,convenience receptacles, and the point at whichthey exit from the unit.Nonuse Periods Unplug the power cord of theunit from the outlet when the unit is to be leftunused for a long period of time.Water and Moisture Do n

19、ot use the unit nearwater for example, near a sink, in a wetbasement, near a swimming pool, near an openwindow, etc.Object and Liquid Entry Do not allow objects tofall or liquids to be spilled into the enclosurethrough openings.Cleaning The unit should be cleaned only asrecommended by the manufactur

20、er.Servicing Do not attempt any service beyondthat described in the operating instructions. Referall other service needs to qualified servicepersonnel.Damage Requiring Service The unit should beserviced by qualified service personnel when:the power supply cord or the plug has beendamaged; objects ha

21、ve fallen or liquid has beenspilled into the unit; the unit has been exposed torain; the unit does not appear to operate normallyor exhibits a marked change in performance; theunit has been dropped, or the enclosuredamaged.MC-12/MC-12 Balanced Service ManualSAFETY SUMMARYThe following general safety

22、 precautions must be observed during all phases of operation, service and repair of this instrument. Failure tocomply with these precautions or with specific warnings elsewhere in these instructions violates safety standards of design manufacture andintended use of the instrument. Lexicon assumes no

23、 liability for the customers failure to comply with these requirements.GROUND THE INSTRUMENTTo minimize shock hazard the instrument chassis and cabinetmust be connected to an electrical ground. The instrument isequipped with a three-conductor AC power cable. The powercable must either be plugged int

24、o an approved three-contactelectrical outlet or used with a three-contact to two-contactadapter with the grounding wire (green) firmly connected to anelectrical ground (safety ground) at the power outlet. The powerjack and mating plug of the power cable meet InternationalElectrotechnical Commission

25、(IEC) safety standards.DO NOT OPERATE IN AN EXPLOSIVEATMOSPHEREDo not operate the instrument in the presence of flammable gasesor fumes. Operation of any electrical instrument in such anenvironment constitutes a definite safety hazard.KEEP AWAY FROM LIVE CIRCUITSOperating personnel must not remove i

26、nstrument covers.Component replacement and internal adjustments must be madeby qualified maintenance personnel. Do not replace componentswith power cable connected. Under certain conditions, dangerousvoltages may exist even with the power cable removed. To avoidinjuries, always disconnect power and

27、discharge circuits beforetouching them.DO NOT SERVICE OR ADJUST ALONEDo not attempt internal service or adjustment unless anotherperson, capable of rendering first aid and resuscitation, is present.DO NOT SUBSTITUTE PARTS OR MODIFYINSTRUMENTBecause of the danger of introducing additional hazards, do

28、 notinstall substitute parts or perform any unauthorized modification tothe instrument.DANGEROUS PROCEDURE WARNINGSWarnings, such as the example below, precede potentiallydangerous procedures throughout this manual. Instructionscontained in the warnings must be followed.WARNINGDangerous voltages, ca

29、pable of causing death, are present in thisinstrument. Use extreme caution when handling, testing andadjusting.SAFETY SYMBOLSGeneral definitions of safety symbols used on equipment or inmanuals. Instruction manual symbol: the product will be markedwith this symbol when it is necessary for the user t

30、o refer to theinstruction manual in order to protect against damage to theinstrument. Indicates dangerous voltage. (Terminals fed from theinterior by voltage exceeding 1000 volts must be so marked.)WARNINGThe WARNING sign denotes a hazard. It calls attention to aprocedure, practice, condition or the

31、 like which, if not correctlyperformed or adhered to, could result in injury or death topersonnel.CAUTIONThe CAUTION sign denotes a hazard. It calls attention to anoperating procedure, practice, condition or the like which, if notcorrectly performed or adhered to, could result in damage to ordestruc

32、tion of part or all of the product.NOTE:The NOTE sign denotes important information. It calls attention toprocedure, practice, condition or the like which is essential tohighlight.CAUTIONElectrostatic Discharge (ESD) PrecautionsThe following practices minimize possible damage to ICs resultingfrom el

33、ectrostatic discharge or improper insertion. Keep parts in original containers until ready for use. Avoid having plastic, vinyl or styrofoam in the work area. Wear an antistatic wrist-strap. Discharge personal static before handling devices. Remove and insert boards with care. When removing boards,

34、handle only by non-conductivesurfaces and never touch open-edge connectors except at astatic-free workstation.* Minimize handling of ICs. Handle each IC by its body. Do not slide ICs or boards over any surface. Insert ICs with the proper orientation, and watch for bentpins on ICs. Use static shieldi

35、ng containers for handling and transport.To make a plastic-laminated workbench anti-static, wash with asolution of Lux liquid detergent, and allow drying without rinsing.LexiconTable of ContentsChapter 1 Reference Documents, Required Equipment.1-1Reference Documents. 1-1Required Equipment. 1-1Tools.

36、 1-1Test Equipment. 1-1Chapter 2 General Information.2-1Periodic Maintenance. 2-1Ordering Parts. 2-1Returning Units to Lexicon for Service . 2-1Chapter 3 Specifications.3-1Chapter 4 Performance Verification.4-1Functional Tests. 4-1Initial inspection . 4-1Power Supply Test. 4-1Setup. 4-2Audio Tests I

37、/O. 4-2Audio Performance Verification. 4-10Audio Inputs RCA #1 Left and Right to all Left and Right RCA/XLR Outputs Tests . 4-10All Remaining Audio RCA Inputs Left and Right to Front Left and Right RCA Output Tests . 4-11Audio Inputs RCA #1 Left and Right to Zone 2 Left and Right RCA Fix /Var Output

38、s and Zone 2 XLROutputs Tests. 4-12Audio Inputs RCA #1 Left and Right to Record Left and Right RCA Fix /Var Outputs Tests. 4-13All Digital Audio Inputs Coax, Optical, AES/EBU to the Left and Right Front RCA Outputs Tests . 4-13Video Input / Output Tests. 4-14Composite Inputs to Composite (Main and R

39、ecord) Outputs Tests. 4-14S-Video Inputs to S-Video (Main and Record) Outputs Tests. 4-15Component Inputs to Component Output Tests. 4-16Lexicon Audio Precision ATE Summary . 4-17Chapter 5 Troubleshooting.5-1V1.00 Release Notes. 5-1Diagnostics. 5-2Introduction. 5-2DiagnosticS Categories . 5-2Power-o

40、n Modes. 5-3DiagnosticS Reporting . 5-3Diagnostics Control/Interface. 5-7Power-on Diagnostics. 5-7Extended DiagnosticS Tests. 5-10Extended Diagnostics Suite. 5-11Service Notes. 5-17Removing The Top Cover. 5-17Removing the Video and Analog Boards. 5-18Removing the MEMORY Board. 5-19Removing the Power

41、 Supply Board. 5-19Removing the Front Panel . 5-20Changing Trigger Voltage From 12 Volts to 5 Volts. 5-20Removing the Main Board . 5-20Initialization (Hard Reset) Procedure. 5-20Chapter 6 Theory of Operation.6-1Main Board. 6-1Z180 Host Processor. 6-1MC-12/MC-12 Balanced Service ManualFPGAs.6-3Host I

42、nterface to Other Boards.6-6Video Board & OSD.6-8Analog Board.6-8OPTION Boards.6-9DSP .6-10Audio Routing.6-14Encoder .6-18VCO Board Overview .6-20PLL Overview .6-21Analog BOARD .6-22Overview.6-22Analog Audio Inputs.6-23Mic Inputs and Main A/D Converter.6-23Record and Zone 2 A/D Converters.6-24Record

43、 and Zone 2 D/A converters .6-24Record and Zone 2 Outputs .6-24Main D/A Converters .6-25Main Outputs .6-26Analog FPGA.6-26Control Registers and Main Board Connector.6-28XLR Board Connector, Power Supply Connections and Regulators .6-29xlr board Overview.6-29Main Channels.6-29Zone 2 Variable Channels

44、 .6-30OPTO/MIC Input Board .6-30Video BOARD .6-30Overview.6-30Composite video inputs .6-31Composite video outputs .6-31S-video inputs.6-31Monitor Composite / S-video .6-31Record Composite / S-video.6-32Component Video Switcher .6-32On-Screen Display Signals.6-33Support Logic / FPGA.6-34Sync Stripper

45、 / DC Restorer .6-34Video Control Registers.6-35Power and Control Interface.6-35Chapter 7 - Parts List.7-1MC-12/MC-12 Balanced MAIN BOARD.7-1MC-12/MC-12 Balanced OPTO/MIC BOARD .7-3MC-12/MC-12 Balanced VIDEO BOARD.7-4MC-12/MC-12 Balanced VIDEO RCA BOARD .7-6MC-12/MC-12 Balanced ANALOG I/O BOARD .7-6

46、MC-12/MC-12 Balanced SWITCH/LED BOARD.7-11MC-12/MC-12 Balanced IR/ENCODER BOARD.7-11MC-12/MC-12 Balanced STANDBY BOARD.7-12MC-12/MC-12 Balanced MEMORY BOARD.7-12MC-12/MC-12 Balanced VCO ASSEMBLY.7-12MC12 Balanced ONLY.7-12MC-12B XLR BOARD.7-12MC-12/MC-12 Balanced CHASSIS ASSEMBLY.7-13MC-12/MC-12 Bal

47、anced POWER SUPPLY ASSEMBLY.7-14MC-12/MC-12 Balanced FAN ASSEMBLY .7-14LexiconMC-12/MC-12 Balanced FRONT PANEL MECHANICAL ASSEMBLY. 7-14MC-12/MC-12 Balanced VIDEO MECHANICAL ASSEMBLY. 7-15MC-12/MC-12 Balanced PACKAGING/MISCELLANOUS. 7-15MC-12/MC-12 Balanced POWER CORD OPTIONS. 7-15MC-12/MC-12 Balanc

48、ed MOUNTING OPTION. 7-15MC-12/MC-12 Balanced SPARE ASSEMBLIES. 7-16Chapter 8 Schematics and Drawings .8-1Schematics. 8-1Drawings. 8-1Lexicon1-1Chapter 1 Reference Documents, Required EquipmentReference DocumentsMC-12/MC-12 Balanced User Guide - Lexicon P/N 070-14773, latest revisionRequired Equipmen

49、tTOOLSThe following is a minimum suggested technicians tool kit required for performing disassembly, assemblyand repairs: Clean, antistatic, well-lit work area with grounding wrist strap (1) #1 Phillips tip screwdriver - (Magnetic tip preferred) (1) 14mm socket nut driver (1) Allen hex head wrench (

50、 2.5 mm ) (1) 3/16 hollow nutdriver Solder: 63/37 - Tin/Lead Alloy composition, low residue, no-clean solder Magnification glasses and lamps SMT Soldering/Desoldering bench-top repair stationTEST EQUIPMENTThe following is a minimum suggested equipment list required to perform the proof of performanc