Crown-DC300sII-pwr-sm维修电路原理图.pdf

POWERCHANNEL 1CHANNEL 2I0C0102040503001020405030Applies only to120 VAC NorthAmerican units.DC-300A II 1996 by Crown International, Inc., P.O. Box 1000, Elkhart, Indiana46515-1000 U.S.A. Telephone: 219-294-8000. The DC-300A II isproduced by the Professional Audio Division of Crown International,Inc. Trademark Notice: Amcron, Crown, Com-Tech, IOC, IQSystem and Macro-Tech are registered trademarks of CrownInternational, Inc. Other trademarks are the property of their respectiveowners.K80002D95/96Some models may be exported under the name Amcron.RadioFans.CN 收音机爱 好者资料库WORLDWIDESUMMARY OF WARRANTYThe Crown Audio Division of Crown International, Inc., 1718 WestMishawaka Road, Elkhart, Indiana 46517-4095 U.S.A. warrants to you,the ORIGINAL PURCHASER and ANY SUBSEQUENT OWNER of eachNEW Crown1 product, for a period of three (3) years from the date ofpurchase by the original purchaser (the “warranty period”) that the newCrown product is free of defects in materials and workmanship, and wefurther warrant the new Crown product regardless of the reason forfailure, except as excluded in this Crown Warranty.1 Note: If your unit bears the name “Amcron,” please substitute it for thename “Crown” in this warranty.ITEMS EXCLUDED FROM THIS CROWN WARRANTYThis Crown Warranty is in effect only for failure of a new Crown productwhich occurred within the Warranty Period. It does not cover any productwhich has been damaged because of any intentional misuse, accident,negligence, or loss which is covered under any of your insurancecontracts. This Crown Warranty also does not extend to the new Crownproduct if the serial number has been defaced, altered, or removed.WHAT THE WARRANTOR WILL DOWe will remedy any defect, regardless of the reason for failure (exceptas excluded), by repair, replacement, or refund. We may not elect refundunless you agree, or unless we are unable to provide replacement, andrepair is not practical or cannot be timely made. If a refund is elected, thenyou must make the defective or malfunctioning product available to usfree and clear of all liens or other encumbrances. The refund will be equalto the actual purchase price, not including interest, insurance, closingcosts, and other finance charges less a reasonable depreciation on theproduct from the date of original purchase. Warranty work can only beperformed at our authorized service centers. We will remedy the defectand ship the product from the service center within a reasonable timeafter receipt of the defective product at our authorized service center. Allexpenses in remedying the defect, including surface shipping costs tothe nearest authorized service center, will be borne by us. (You must bearthe expense of all taxes, duties and other customs fees whentransporting the product.)HOW TO OBTAIN WARRANTY SERVICEYou must notify us of your need for warranty service not later than ninety(90) days after expiration of the warranty period. All components must beshipped in a factory pack. Corrective action will be taken within areasonable time of the date of receipt of the defective product by ourauthorized service center. If the repairs made by our authorized servicecenter are not satisfactory, notify our authorized service centerimmediately.DISCLAIMER OF CONSEQUENTIAL AND INCIDENTAL DAMAGESYOU ARE NOT ENTITLED TO RECOVER FROM US ANY INCIDENTALDAMAGES RESULTING FROM ANY DEFECT IN THE NEW CROWNPRODUCT. THIS INCLUDES ANY DAMAGE TO ANOTHER PRODUCTOR PRODUCTS RESULTING FROM SUCH A DEFECT.WARRANTY ALTERATIONSNo person has the authority to enlarge, amend, or modify this CrownWarranty. This Crown Warranty is not extended by the length of timewhich you are deprived of the use of the new Crown product. Repairs andreplacement parts provided under the terms of this Crown Warranty shallcarry only the unexpired portion of this Crown Warranty.DESIGN CHANGESWe reserve the right to change the design of any product from time to timewithout notice and with no obligation to make corresponding changes inproducts previously manufactured.LEGAL REMEDIES OF PURCHASERNo action to enforce this Crown Warranty shall be commenced later thanninety (90) days after expiration of the warranty period.THIS STATEMENT OF WARRANTY SUPERSEDES ANY OTHERSCONTAINED IN THIS MANUAL FOR CROWN PRODUCTS.9/90NORTH AMERICASUMMARY OF WARRANTYThe Crown Audio Division of Crown International, Inc., 1718 West MishawakaRoad, Elkhart, Indiana 46517-4095 U.S.A. warrants to you, the ORIGINALPURCHASER and ANY SUBSEQUENT OWNER of each NEW Crown prod-uct, for a period of three (3) years from the date of purchase by the originalpurchaser (the “warranty period”) that the new Crown product is free of defectsin materials and workmanship. We further warrant the new Crown productregardless of the reason for failure, except as excluded in this Warranty.ITEMS EXCLUDED FROM THIS CROWN WARRANTYThis Crown Warranty is in effect only for failure of a new Crown product whichoccurred within the Warranty Period. It does not cover any product which hasbeen damaged because of any intentional misuse, accident, negligence, orloss which is covered under any of your insurance contracts. This CrownWarranty also does not extend to the new Crown product if the serial numberhas been defaced, altered, or removed.WHAT THE WARRANTOR WILL DOWe will remedy any defect, regardless of the reason for failure (except asexcluded), by repair, replacement, or refund. We may not elect refund unlessyou agree, or unless we are unable to provide replacement, and repair is notpractical or cannot be timely made. If a refund is elected, then you must makethe defective or malfunctioning product available to us free and clear of all liensor other encumbrances. The refund will be equal to the actual purchase price,not including interest, insurance, closing costs, and other finance charges lessa reasonable depreciation on the product from the date of original purchase.Warranty work can only be performed at our authorized service centers or atthe factory. We will remedy the defect and ship the product from the servicecenter or our factory within a reasonable time after receipt of the defectiveproduct at our authorized service center or our factory. All expenses inremedying the defect, including surface shipping costs in the United States,will be borne by us. (You must bear the expense of shipping the productbetween any foreign country and the port of entry in the United States and alltaxes, duties, and other customs fees for such foreign shipments.)HOW TO OBTAIN WARRANTY SERVICEYou must notify us of your need for warranty service not later than ninety (90)days after expiration of the warranty period. All components must be shippedin a factory pack, which, if needed, may be obtained from us free of charge.Corrective action will be taken within a reasonable time of the date of receiptof the defective product by us or our authorized service center. If the repairsmade by us or our authorized service center are not satisfactory, notify us orour authorized service center immediately.DISCLAIMER OF CONSEQUENTIAL AND INCIDENTAL DAMAGESYOU ARE NOT ENTITLED TO RECOVER FROM US ANY INCIDENTALDAMAGES RESULTING FROM ANY DEFECT IN THE NEW CROWNPRODUCT. THIS INCLUDES ANY DAMAGE TO ANOTHER PRODUCT ORPRODUCTS RESULTING FROM SUCH A DEFECT. SOME STATES DONOT ALLOW THE EXCLUSION OR LIMITATIONS OF INCIDENTAL ORCONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION OREXCLUSION MAY NOT APPLY TO YOU.WARRANTY ALTERATIONSNo person has the authority to enlarge, amend, or modify this Crown Warranty.This Crown Warranty is not extended by the length of time which you aredeprived of the use of the new Crown product. Repairs and replacement partsprovided under the terms of this Crown Warranty shall carry only the unexpiredportion of this Crown Warranty.DESIGN CHANGESWe reserve the right to change the design of any product from time to timewithout notice and with no obligation to make corresponding changes inproducts previously manufactured.LEGAL REMEDIES OF PURCHASERTHIS CROWN WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS, YOUMAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM STATE TO STATE.No action to enforce this Crown Warranty shall be commenced later thanninety (90) days after expiration of the warranty period.THIS STATEMENT OF WARRANTY SUPERSEDES ANY OTHERSCONTAINED IN THIS MANUAL FOR CROWN PRODUCTS.9/90Telephone: 219-294-8200. Facsimile: 219-294-8301Telephone: 219-294-8200. Facsimile: 219-294-8301THREE YEARFULL WARRANTYYEAR3YEAR3RadioFans.CN 收音机爱 好者资料库C A U T I O NRISK OF ELECTRIC SHOCKDO NOT OPENTO PREVENT ELECTRIC SHOCK DONOT REMOVE TOP OR BOTTOM COV-ERS. NO USER SERVICEABLE PARTSINSIDE. REFER SERVICING TO QUALI-FIED SERVICE PERSONNEL.A V I SRISQUE DE CHOC LECTRIQUENOUVREZ PAS PRVENIR LE CHOC LECTRIQUENENLEVEZ PAS LES COUVERCLES. ILNY A PAS DES PARTIES SERVICEABLE LINTRIEUR. TOUS REPARATIONSDOIT ETRE FAIRE PAR PERSONNELQUALIFI SEULMENT.Printed onrecycled paper.The lightning bolttriangle is used toalert the user to therisk of electric shock.The exclamation pointtriangle is used to alert theuser to important operating ormaintenance instructions.WARNINGTO REDUCE THE RISK OF ELECTRICSHOCK, DO NOT EXPOSE THISEQUIPMENT TO RAIN OR MOISTURE!Magnetic FieldCAUTION! Do not locate sensitive high-gain equip-ment such as preamplifiers or tape decks directlyabove or below the unit. Because this amplifier hasa high power density, it has a strong magnetic fieldwhich can induce hum into unshielded devices thatare located nearby. The field is strongest just aboveand below the unit.If an equipment rack is used, we recommend locatingthe amplifier(s) in the bottom of the rack and thepreamplifier or other sensitive equipment at the top.The information furnished in this manual does not include all of the details of design, production, or variations ofthe equipment. Nor does it cover every possible situation which may arise during installation, operation or main-tenance. If your unit bears the name “Amcron,” please substitute it for the name “Crown” in this manual. If youneed special assistance beyond the scope of this manual, please contact our Technical Support Group.Crown Audio Division Technical Support Group57620 C.R. 105, Elkhart, Indiana 46517 U.S.A.Phone: 800-342-6939 (North America, Puerto Rico and Virgin Islands) or 219-294-8200Fax: 219-294-8301 Fax Back: 800-294-4094 (North America only) or 219-293-9200Internet: http:/DC-300A II Power AmplifierPage 4CONTENTS1Welcome. 71.1Unpacking. 71.2Features . 72Facilities . 83Installation. 93.1 Mounting . 93.2 Cooling . 93.3 Wiring . 93.3.1 Mode of Operation . 93.3.2 Input Connection. 113.3.3 Output Connection. 123.3.4 Additional Load Protection . 133.3.5 AC Mains Power Requirement. 144Operation. 154.1 Precautions . 154.2 Indicators . 154.3 Controls . 154.4 Protection . 154.5 Fuse Replacement . 165Technical Information . 175.1 Principles of Operation . 176Specifications . 187Internal Settings. 237.1 26 dB Gain vs. 0.775 V Input Sensitivity . 237.2 Changing the Input Sensitivity to 0.775 V. 238Service. 248.1 Worldwide Service . 248.2 North American Service. 248.2.1 Service at a North American Service Center . 248.2.2 Factory Service . 24DC-300A II Power AmplifierPage 5ILLUSTRATIONS1.1DC-300A II.72.1Facilities.83.1Mounting Dimensions .93.2System Connection.103.3Input Wiring .113.4Subsonic Filter Capacitors .113.5Unbalanced RFI Filters .113.6Balanced RFI Filters.113.7Wire Size Nomograph .123.8Inductive Load (Transformer) Network .133.9Fuse Selector Nomograph .143.10 AC Mains Voltage Conversion.145.1Circuit Block Diagram .166.1Power Matrix .196.2Nominal Output Impedance.206.3Nominal Output Phase Angle .206.4Nominal Damping Factor .206.5Nominal Phase Response .216.6Nominal Crosstalk.216.7Nominal Power Efficiency.216.8Nominal Noise Spectrum .226.9Nominal Frequency Response .227.1Main Circuit Board .23DC-300A II Power AmplifierPage 6Rev. 0DC-300A II Power AmplifierPage 7POWERCHANNEL 1CHANNEL 2I0C01020405030010204050301 WelcomeCongratulations on purchasing a Crown DC-300A II.Your amplifier is designed to provide reliable operationwith a variety of loads. It is a versatile choice for use instudios, laboratories, public facilities and on the road.And the sonic excellence of the DC-300A II makes it avery good choice for your personal listening pleasure.Using innovative circuitry, the DC-300A II yields ultra-low distortion through a wide range of frequencies fromDC (0 Hz) to 20 kHz. The amplifiers output transistorsare “direct coupled” to the load so there are no outputcapacitors or transformers to compromise its superbsonic integrity. The tremendous output power of theDC-300A II enables it to deliver balanced 70 volt out-put in Bridge-Mono mode without using costly “step-up” transformers. And Crowns innovative JTS(Junction Temperature Simulation) circuitry dynami-cally adjusts the output protection system for unparal-leled sonic headroom. Crown further protects yourinvestment with the industrys only three year “No-Fault”full warranty. After reading this manual and learningabout the features, facilities and capabilities of youramplifier, you will understand why Crown amplifiers arerecognized as the worldwide standard for audio excel-lence.For your protection, please send in your warranty reg-istration card and save your bill of sale, as it is yourofficial proof of purchase.1.1 UnpackingPlease unpack and inspect your new amplifier for anydamage that may have occurred during transit. If dam-age is found, notify the transportation company imme-diately. Only you may initiate a claim with the carrier fordamage resulting during shipment. Even if the unit ar-rived in perfect condition, as most do, save all packingmaterials so you will have them if you ever need totransport the unit. NEVER SHIP THE UNIT WITHOUTTHE FACTORY PACK.1.2 FeaturesYour dual channel (stereo) amplifier can be configuredfor higher-powered single channel operation. It alsoprovides the following features:AB+B class circuitry for maximum efficiency with mini-mum crossover “notch” distortion.IOC (Input/Output Comparator) alerts of distortion ex-ceeding 0.05% to provide proof of performance.Ultra-low harmonic and intermodulation distortion resultin the best dynamic transfer function in industry.Very low noise level and wide dynamic range exceeddigital audio standards.Exclusive JTS (Junction Temperature Simulation) cir-cuitry protects the output devices and provides excep-tional dynamic headroom.High damping factor gives you greater loudspeaker mo-tion control.Bridge-Mono output can drive 70 volt “constant voltage”lines without expensive, distortion-producing “step-up”transformers.Convection cooling with integrated heat sink/chassis de-sign for maintenance-free operation.Mounts in a standard 19 inch (48.3 cm) rack.Three year “No-Fault” full warranty protects your invest-ment and guarantees the specifications of units in NorthAmerica and other select countries.Fig. 1.1 DC-300A IIDC-300A II Power AmplifierPage 8POWERCHANNEL 1CHANNEL 2I0C010204050300102040503