Hafler-9270-pwr-sm维修电路原理图.pdf

RadioFans.CN 收音机爱 好者资料库Series 9180/9270 Power AmplifierNOTICE - IMPORTANT SAFETY INFORMATIONWARNING: TO PREVENT FIRE ORSHOCK HAZARD, DO NOT EXPOSE THISEQUIPMENT TO RAIN OR MOISTURE.The lightning flash with arrowhead symbol withinan equilateral triangle is intended to alert theuser to the presence of uninsulated “dangerousvoltage” within the products enclosure, that maybe of sufficient magnitude to constitute a risk ofelectric shock to persons.The exclamation point within an equilateraltriangle is intended to alert the user of thepresence of important operating and mainte-nance (servicing) instructions in the literatureaccompanying the appliance.1 .READ INSTRUCTIONSAll the safety and operating instructions of your Hafler equipment should be read before power is applied to theequipment.2 .RETAIN OWNERS MANUALThese safety and operating instructions should be retained for future reference.3 .HEED WARNINGSAll warnings on the equipment and in the operating instructions are important and should be followed.4 .FOLLOW INSTRUCTIONSAll operating and use instructions are important and should be followed.5.HEATThe equipment should be kept away from areas of high temperature, such as heater vents, radiators, stoves/ovens,fireplaces, etc.6 .VENTILATIONThe equipment should be used in an area suitable for proper ventilation. Care should be taken not to impede airflowin and around the cabinet. Do not mount on a carpeted shelf or in a sealed enclosure. Allow for proper clearanceabove the equipment.7 .WATER AND MOISTUREThe equipment should not be used in or around water, such as a bathtub, sink, or swimming area. Also, the equipmentshould not be used in areas prone to flooding, such as a basement.a .a .POWER SOURCESThe equipment should be connected only to a power source of the same voltage and frequency as that listed on therear panel above the power cord entry point.9 .POWER CORD PROTECTIONPower cords should be arranged so that they do not interfere with the movement of objects in the room: people, fanblades, utility carts, etc. Also, care should be taken that the cord is not pinched or cut, and placed so that it is notin danger of being pinched or cut, as in under a rug, around a tight corner, etc.10. POWER CORD GROUNDINGThe power supply cord is of a three wire grounded type, designed to reduce the risk of electric shock sustained froma live cabinet. It is assumed to be of suitable length for most uses of the equipment. The use of extension cords andpower strips is discouraged unless they are of suitable rating to deliver the required total current for safe operationof all connected equipment. Furthermore, extension cords or power strips must provide the same three wiregrounded connection. It is important that the blades of the equipments plug be able to fully insert into the matingreceptacle. Never remove the round grounding pin on the plug in an attempt to mate to a two wire ungroundedreceptacle: use a grounding adaptor with the grounding tab or wire suitably connected to earth ground.-1-RadioFans.CN 收音机爱 好者资料库11. NON-USE PERIODSDuring periods of extended non-use, the power cord should be unplugged from the power source.12. CLEANINGThe equipment should be cleaned only as detailed in the operating instructions.13.OBJECT AND LIQUID ENTRYCare should be taken so that objects and/or liquids, such as cleaning fluids or beverages, are not spilled into theenclosure of the equipment.14. DAMAGE REQUIRING SERVICEHafler equipment should be serviced by qualified service personnel when:A. The power supply cord or plug has been damaged, orB. Objects have fallen, or liquid has been spilled into the equipment, orC. The equipment has been exposed to rain, orD. The equipment does not appear to operate normally or exhibits a marked change in performance, orE. The equipment has been dropped, or the enclosure has been damaged.15. SERVICINGThe user should not attempt to service the equipment beyond that which is described in the operating instructions.All other service should be referred to qualified service personnel.16. CARTS AND STANDSThe equipment should be used with carts or stands only of sufficient strength and stability for the use intended.An equipment and cart combination should be moved with care. Quick stops and starts, excessive force, anduneven surfaces may cause the equipment and cart combination to topple.-2-TABLE OF CONTENTSPERFORMANCE SPECIFICATIONS . 4General Information . 4INSTALLATIONRackmounting.5Ventilation/Placement. . 5Line Voltage.5OPERATION/CONNECTIONSPower Cord Connection/Power Switch. . 5Inputs .5Front Panel View Diagram. . 6Rear Panel View Diagram . 7Outputs.8Gain Controls. . 8Mono/Stereo Switching. 8Soft Turn-On System . 8Thermal Protection System . 8CIRCUIT HIGHLIGHTS . 9ADDITIONAL INFORMATIONLoudspeaker Load Impedance Considerations.10Changing Line Voltage Rating.10AdjustingBias .10General TroubleshootingHints .11GroundLoops .1 1Cleaning/Maintenance . 12Parts List. .12Functional Block Diagram. . 14Component Layout Diagram. . 15Circuit Schematic Diagram . 17SERVICE POLICY AND LIMITED WARRANTY. 19-3-PERFORMANCE SPECIFICATIONSGENERALINFORMATIONAll specifications are for 20 Hz - 20 kHz, at full power into 8 ohms, unless specified otherwise.Power Rating: 9180:9270:Rated THD:Full Power Bandwidth:Signal to Noise Ratio:Input Impedance:Input Sensitivity: 9180:9270:Damping Factor:Slew Rate:Controls:Inputs:outputs:Power Consumption:Size:Weight:9180:9270:105 watts per channel (8 ohms)150 watts per channel (4 ohms)300 watts mono (8 ohms)135 watts per channel (8 ohms)200 watts per channel (4 ohms)400 watts mono (8 ohms)less than 0.025%, typically 0.005% at 1 kHz0.3 Hz to 116 kHzgreater than 100 dB, unweighted47,000 ohms1.4 volts RMS1.6 volts RMS300 to 1 kHz, 200 to 10 kHz50 V/uSPower Switch, Left/Right Gain Controls, Mono/Stereo SwitchRight and Left/Mono RCA jacksRight, Left, and Mono 5-Way Binding Posts100 watts quiescent, 1200 watts maximum17”(W) x 12.5”(D) w3.5”(H) excluding feet, faceplate 17” or 19”(W)43.2cm(W) x 31.7cm(D) x 8.9cm(H) excluding feet,faceplate 43.2cm or 48.3cm(W)33 Ibs., 15 kg, net.35 Ibs., 15.9 kg, net.-4-INSTALLATIONRACK-MOUNTINGVENTILATION/PLACEMENTLINEVOLTAGEThe 9180/9270 Amplifier is supplied in either a 17” Black Version, or a 19” Silver Version. The 19”model has rackmounting holes provided for installation in equipment racks. The holes are on standardEIA spacings.Due to conflict with adjacent equipment, it may be advisable to remove the four rubberfeet from the bottom of the unit. The feet may be removed from the outside, with no dis-assembly ofthe chassis necessary.The 9180/9270 Amplifier can produce considerable heat during normal operation. The amplifier shouldbe placed on a hard, smooth surface to allow air to circulate beneath the unit. Additionally, allow at leastone inch of free space on either side, and several inches above and behind the amplifier to allow aircirculation around the heatsinks. This is particularly important when the unit is installed in a closedcabinet.In applications where the amplifier is driving low impedance and/or low efficiency loudspeakers at highlevels, thermal shutdown may occur if inadequate ventilation is provided. If this occurs, it may benecessary to move the amplifier to a location with better free air circulation.The amplifier should be located at least several inches away from sensitive components, (such aspreamplifiers, tuners, CD players, turntables, etc.) due to the possibility of audible hum or buzz frommagnetic radiation.The 9180/9270 Amplifier is configurable for either 100, 120, 220 or 240 volt operation. This isaccomplished by moving the Voltage Selector on the printed circuit board. The procedure is detailedin the section “CHANGING LINE VOLTAGE RATING”.Make sure that the unit is configured for your local AC line voltage before attempted use. Theconfiguration is labelled directly above the power cord connector.OPERATION/CONNECTIONSPOWER CORDCONNECTION/POWER SWITCHINPUTSUnits wired for 100, 220 and 240 VAC are supplied without power cords. Local agents will supply cordswith male connectors appropriate to the local standard.Units wired for 120 VAC are supplied with a detachable AC power cord. The female connector plugsinto the receptacle provided on the rear panel. This power cord is a standard IEC Type 320, 3-wire,16 gauge assembly. Should replacement ever be necessary, be sure to replace it with an identical cord.Never remove the grounding pin from the male end of the cord. In applications where a grounded outletis not available, a ground adaptor should be employed, with the ground tab or wire of the adaptorconnected to a suitable earth ground.The AC power cord of the amplifier must be connected to a receptacle capable of delivering a minimumof 1200 watts. The convenience outlets of some preamplifiers are not rated for this power level. Beforeconnecting the amplifier, be sure to check the rating of such outlets, and take into account the powerconsumption of any other connected components to determine the total maximum power consumption.If the amplifier is connected to a component with a switched convenience outlet, then the amplifiersPower Switch may be left ON at all times, and the power controlled by the switched outlet. If the amplifieris connected to an unswitched outlet, then the amplifiers power should be controlled by the front panelPower Switch.All input connections to the amplifier must be performed with the amplifier off!The left and right audio inputs to the amplifier are via standard RCA jacks.In addition to the printedlabelling above the jacks, the channels are identified by RED for right channel, and WHITE for leftchannel. Connect these jacks to the output of the preamplifier or other signal source.When operating the amplifier in the Mono Mode, only the left channel input should be used.-5-IEC Type 320, 3-wire,LEFT/MONOGAINPOWER SWITCHU P - O NDOWN - OFFRACKMOUNT HOLESRIGHTRACK HANDLES(19” VERSION ONLY)GAIN(19” VERSION ONLY)9180 / 9270 AMPLIFIER FRONT PANEL VIEWIMONO/STEREOSWITCHIN -MONO RIGtO U T -ISTEREO INAC LINEVOLTAGERATINGLINECORDCONNECTOR-T T-iTITLEFT/MONOINPUTMONO+OUTPUTRIGHT+ -LEFTOUTPUT OUTPUTI!I9180 / 9270 AMPLIFIER REAR PANEL VIEWOUTPUTSIAll output connections to the amplifier must be performed with the amplifier off!The left and right audio outputs from the amplifier are via standard 5-way type, 3/4” spacing,binding posts. Connect these binding posts to the loudspeakers. The amplifiers binding posts willaccept single or dual banana plugs, spade lugs, pin plugs, or bare wires. If using bare wires, it isrecommended that the ends of the wire be tinned with solder so that no stray strands can causea short circuit to the chassis or adjacent terminals.To ensure proper speaker phasing and frequency response, be sure to connect each respectiveamplifier RED (+) terminal to the speaker RED (+) terminal, and the amplifier BLACK (-) terminalto the speaker BLACK (-) terminal. The polarity symbols (+/-) for Stereo Mode are labelled belowthe amplifiers binding posts.For operation in the Mono Mode, a single loudspeaker should be connected to the two RED bindingposts only. No connection is made to the amplifiers BLACK binding posts. Connect the speakersRED (+) terminal to the amplifiers RED terminal labelled (+), and the speakers BLACK (-) terminalto the amplifiers RED terminal labelled (-). The polarity symbols (+/-) for the Mono Mode arelabelled above the amplifiers binding posts.GAINCONTROLSMONO/STEREOSWITCHINGSOFT TURN-ON/OFFSYSTEMTHERMALPROTECTIONSYSTEMThe 9180/9270 Amplifier is equipped with front panel mounted Gain Controls. These controls maybe used to attenuate the input signal to the amplifier. The maximum clockwise position of thesecontrols applies the full input signal to the amplifier. Intermediate positions of these controls willpartially attenuate the signal, and the full counter-clockwise position attenuates the input signalcompletely.Most applications will dictate that these controls be set to their maximum clockwise position.Insituations of unusually high level signal sources, or for matching levels in multiple amplifierinstallations, it may be desirable to use an intermediate position of the Gain Controls. Unlessintentionally introducing different gain levels in the two channels of the amplifier, these controlsshould normally be set at the same rotational position.In the Mono Mode, the Left Gain Control effects the overall gain of the amplifier. The Right GainControl has no effect.The 9180/9270 Amplifier may be operated in the normal two channel Stereo Mode, or may beconverted (bridged) to a higher power, single channel amplifier in the Mono Mode.Operation of the Stereo/Mono switch must be performed with the amplifier off! Set the Stereo/Mono Switch in the OUT position for Stereo Mode, or in the IN position for Mono Mode. Mono Modeoperation requires different input and output connections: consult the sections of the manual titled“Inputs” and “Outputs”.The 9180/9270 Amplifier is equipped with a Soft Turn-On/Off System that gradually activates theamplifiers circuitry to avoid spurious noises as the power supply stabilizes.At turn-off, this same system rapidly deactivates the amplifiers circuitry before the power supplybegins to collapse, again eliminating any spurious noises.The 9180/9270 Amplifier is equipped with a Thermal Protection System that constantly monitorsthe temperature of the heatsinks. When the heatsink temperature reaches a pre-determined level,the amplifiers circuitry is electronically shut down through the same system that provides the SoftTurn-On function. When the heatsinks cool to a safe operating temperature, normal operation ofthe amplifier resumes.-8-5-way type, 3/4 spacing,CIRCUIT HIGHLIGHTSThe input stage of the 9180/9270 Amplifier utilizes four low-noise, High-g, JFETs (high transconductancejunction field-effect transistors), in a fully complimentary, symmetric configuration. This circuit configu-ration results in excellent front-end headroom and a simple, straightforward connection to theremainder of the circuitry. The ultra low noise characteristics of the JFETs virtually eliminates noise“mixing” (intermodulation) with the music signal, reducing discordant product frequencies known as“noise grain”, or “noise fuzz”.The input stage is cascode connected to convert the low voltage input system to the high voltage outputsystem, and “speeds up” the front end for superior bandwidth. The cascode stage is connected to anemitter-follower and current mirror configuration that amplifies the current level about ten times,necessary to drive the biasing string and final output stage driver emitter followers.The final output stage uses multiple lateral MOSFETs (Metal Oxide Semiconductor Field EffectTransistors): four devices per channel in the 9180, and six per channel in the 9270. These devices,unlike conventional bipolar transistors, have a negativetemperature coefficient, which means that theydo not exhibit “therm