Bose-1800-pwr-sm维修电路原理图.pdf

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1、Bose Model 1801/1800 Power Amplifiers1997 Bose CorporationPart Number 192527 REV 01Service ManualRadioFans.CN 收音机爱 好者资料库1 PROPRIETARY INFORMATIONTHIS DOCUMENT CONTAINS PROPRIETARY INFORMATION OFBOSE CORPORATION WHICH IS BEING FURNISHED ONLY FORTHE PURPOSE OF SERVICING THE IDENTIFIED BOSE PRODUCTBY A

2、N AUTHORIZED BOSE SERVICE CENTER OR OWNER OF THE BOSE PRODUCT, AND SHALL NOT BE REPRODUCED OR USED FOR ANY OTHER PURPOSE.ContentsSpecifications. 2Safety Information. 3Electrostatic Discharge Sensitive (ESDS) Device Handling . 4Disassembly/Assembly Procedures . 5-8Test Procedures . 9Figure 1. 1801 Co

3、mponent Location. 10Figure 2. 1801 Side View . 10Figure 3. 1800 Front Panel . 11Figure 4. 1800 Rear View of Front Panel . 11Figure 5. 1801 Rear View of Front Panel . 11Figure 6. 1800 Rear Panel . 12Figure 7. 1801 Rear Panel . 12Part List Notes. 13Figure 8. 1801 Front Panel . 13Part List. 14-17Figure

4、 9. 1801/1800 Block Diagram. 18Figure 10. LED PCB Layout. 19Figure 11. LED PCB Schematic Diagram . 20Figure 12. Amplifier Schematic Diagram. 21Figure 13. Amplifier PCB Layout . 22Troubleshooting Guide. 23Voltage Conversion Instructions . 24Service Bulletin . 25-28RadioFans.CN 收音机爱 好者资料库2SPECIFICATIO

5、NSMechanicalDimensions:180118007 3/16 H x 18 W x 18 1/2 D (Including Knobs)81/4H x 19W x 15D (not including handles)Weight:1801180082 lbs95 lbs (shipping)80 lbs91 lbs (shipping)Power RequirementsVoltage:105-125 AC USA, 210-250 AC EURFrequency:50-60 HzPower Consumption:Minimum 60 wattsNormal 1000 wat

6、tsMaximum 1960 wattsIntegral DesignAmplifierOutput :(both channels operating )250/250 watts 8 ohms400/400 watts 4 ohmsHarmonic Distortion:(THD) 250 wattsLess Than .15% (20Hz-5kHz)Less Than .5% (5kHz-10kHz)IM Distortion:(4:1 60-7kHz) 150 wattsLess Than .15%Frequency Response:20Hz-10kHz .25dB10kHz-15k

7、Hz .7dB15kHz-20kHz 1dBSignal to Noise Ratio:(unweighted)-100dB .5mV across 8 at zero volumeLoad Impedance:4 ohms or higherInput Sensitivity:1.5 Vrms for 250 watts output into 8 ohms Input Impedance:50,000 ohms or higher3SAFETY INFORMATION 1. Parts that have special safety characteristics are identif

8、ied by the symbol on schematics or by special notes on the parts list. Use only replacement parts that have critical characteristics recommended by the manufacturer. 2. Make leakage current or resistance measurements to determine that exposed parts are acceptably insulated from the supply circuit be

9、fore returning the unit to the customer. Use the following checks to perform these measurements:A. Leakage Current Hot Check-With the unit completely reassembled, plugthe AC line cord directly into a 120V AC outlet. (Do not use an isolationtransformer during this test.) Use a leakage current tester

10、or a meteringsystem that complies with American National Standards Institute (ANSI)C101.1 “Leakage Current for Appliances” and Underwriters Laboratories(UL) 1492 (71). With the unit AC switch first in the ON position, then in theOFF position, measure from a known earth ground (metal water pipe,condu

11、it, etc.) to all exposed metal parts of the unit (antennas, handle bracket,metal cabinet, screwheads, metallic overlays, control shafts, etc.), especiallyany exposed metal parts that offer an electrical return path to the chassis.Any current measured must not exceed 0.5 milliamp. Reverse the unit po

12、wercord plug in the outlet and repeat test. ANY MEASUREMENTS NOT WITHINTHE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL SHOCK HAZ- ARD THAT MUST BE ELIMINATED BEFORE RETURNING THE UNIT TO THE CUSTOMER.B. Insulation Resistance Test Cold Check-(1) Unplug the power supply andconnect a jumper wire betwe

13、en the two prongs of the plug. (2) Turn on the power switch of the unit. (3) Measure the resistance with an ohmmeter be- tween the jumpered AC plug and each exposed metallic cabinet part on the unit. When the exposed metallic part has a return path to the chassis, the reading should be between 1 and

14、 5.2 Megohms. When there is no return path to the chassis, the reading must be “infinite”. If it is not within the limits specified, there is the possibility of a shock hazard, and the unit must be repaired and re- checked before it is returned to the customer.4ELECTROSTATIC DISCHARGE SENSITIVE (ESD

15、S)DEVICE HANDLINGCAUTION: THE BOSE 1801/1800 POWER AMPLIFIERS CONTAIN NO USER-SERVICE-ABLE PARTS. TO PREVENT WARRANTY INFRACTIONS, REFER SERVICE TO WAR-RANTY SERVICE STATIONS OR FACTORY SERVICE.This unit contains ESDS devices. We recommend the following precautions when repairing,replacing or transp

16、orting ESDS devices: Perform work at an electrically grounded work station. Wear wrist straps that connect to the station or heel straps that connect to conductive floormats. Avoid touching the leads or contacts of ESDS devices or PC boards even if properlygrounded. Handle boards by the edges only.

17、Transport or store ESDS devices in ESD protective bags, bins, or totes. Do not insert unpro-tected devices into materials such as plastic, polystyrene foam, clear plastic bags, bubblewrap or plastic trays.General DescriptionThe 1801 and 1800 are Integral Design Power Amplifiers with all Silicon Soli

18、d-State Circuitryusing 14 power transistors per channel. Capable of complete stability with all loudspeakerloads regardless of capacitive or inductive character. They employ fast acting electronic pro-tection circuits for current limiting. They use computer grade capacitors throughout the powersuppl

19、y, along with a 2.0kW power transformer and 1300 sq. inches of heat sink area. They alsohave a power monitor display using a light emitting diode array and in the case of the 1801signal meters as well.5DISASSEMBLY/ASSEMBLY PROCEDURES1801 Power AmplifierNote: Refer to Figure 1 for the followingproced

20、ures.1. Top Cover Removal1.1 Remove the two screws that securethe top cover at the rear of the unit. Loosenthe two screws located on each side of theunit towards the front.1.2 Slide the top cover towards the rear ofthe unit and lift the cover off the unit.2. Top Cover Replacement2.1 Slide the top co

21、ver onto the unit whilemaking sure the screws on the side of theunit are lining up with the slots in the topcover.2.2 Secure the top cover to the unit.3. Amplifier PCB Removal3.1 Perform procedure 1.3.2 Disconnect the wire harness, the twowires connected to the thermal cutout, andthe input cable goi

22、ng to the PCB.3.3 Remove the six screws (2B) located onthe side of the unit between the heat sinkfins (see Figure 2).3.4 Carefully pry the PCB inward towardsthe power transformer (the PCB is stuck tothe chassis by the heat sinking compound)and lift the board out of the unit.4. Amplifier PCB Replacem

23、ent4.1 Slide the PCB into place. Be sure thereis sufficient heat sink compound on thePCBs heat sink.4.2 Align the six screws that secure thePCB into place and secure the PCB to thechassis.4.3 Connect the wire harness, thermalcutout wires, and the input cable to thePCB.5. Front Panel Removal5.1 Perfo

24、rm procedure 1.5.2 Remove the nut securing the top of thefront panel. The nut is located on the insideof the front chassis beside the thermalcutout indicator.5.3 Remove the knobs on the controls andremove the two shaft nuts holding the frontpanel in place.6. Front Panel Replacement6.1 Align the fron

25、t panel over the controlsand secure it in place.6.2 Secure the top of the front panel andreplace the knobs.6.3 Perform procedure 2.7. Front Chassis Assembly Removal7.1 Perform procedure 5.7.2 Locate and remove the four screwsthat secure the front assembly to thechassis.7.3 Push down on the top of th

26、e frontassembly to release the bottom of theassembly and pull the assembly towardsyou.8. Front Chassis Assembly Replacement8.1 While pushing down on the frontassembly slide the assembly in towards theunit.8.2 Pull up on the front assembly to alignthe screw holes with the unit and securethe assembly

27、in place.8.3 Perform procedure 6.61801 Power AmplifierDISASSEMBLY/ASSEMBLY PROCEDURESassembly. Connect the wires going to themeter.12.2 Place the meter lamp housing overthe meters and secure it to the front assem-bly.12.3 Perform procedure 8.Note: Refer to Figure 5 for the followingprocedures.9. LED

28、 PCB Removal9.1 Perform procedure 7.9.2 Unsolder the wires to the LED PCBand make a note of the wiring configura-tion.9.3 Remove the center nut located oneach side on the LED lamp housing.9.4 Lift the LED assembly out from thefront chassis.9.5 Disassemble the LED assembly to gainaccess to the PCB.No

29、te: Remember how the lamp housingspacers are placed.10. LED PCB Replacement10.1 After reassembling the LED assem-bly, place it onto the front panel assemblyand secure it in place.10.2 Resolder the wires to the PCB.10.3 Perform procedure 8.11. Meter Assembly Removal11.1 Perform procedure 7.11.2 Remov

30、e the three nuts holding themeter lamp housing assembly to the frontpanel assembly.11.3 Remove the two nuts holding thewires to the meter you want to replace andremove the meter.12. Meter Assembly Replacement12.1 Place the new meter on to the front13. Front Panel Controls Removal13.1 Perform procedu

31、re 7.13.2 Locate the control or switch you wantto replace and unsolder the wires andcomponents on that control or switch.13.3 Remove the shaft nut holding thecontrol or switch to the front assembly andremove it.14. Front Panel Controls Replacement14.1 Place the new control or switch intothe front as

32、sembly and secure it in place.14.2 Resolder the wires and/ or compo-nents to the control or switch.14.3 Perform procedure 8.15. Lamp Removal15.1 Perform procedure 7.15.2 Using a flat blade screwdriver, pryunder the edge of the socket and lift thesocket out.16. Lamp Replacement16.1 Replace the defect

33、ive lamp.16.2 Place the lamp socket back into thelamp housing.16.3 Perform procedure 8.Note: It may be necessary to remove theLED PCB Assembly to replace the lampssee procedure 9.7DISASSEMBLY/ASSEMBLY PROCEDURES5.2 Locate and remove the eight screwsholding the front panel to the chassis. Fourof the

34、screws are located just inside thetwo handles and the other four are thelarger screws on the front panel.5.3 Using the handles pull the front panelaway from the chassis enough to accessthe gain controls and LED PCB.6. Front Panel Replacement6.1 Slide the front panel into place. Becareful not to pinc

35、h the wiring harness atthe bottom of the front panel between it and the chassis.6.2 Align the holes in the front panel withthe chassis, place the screws into theirlocation by hand and then tighten with ascrewdriver.Note: While tightening the screws lift upon the top lip of the panel to provideenough

36、 room to slide the top cover underthe lip.7. LED PCB Removal7.1 Perform procedure 5.7.2 Remove the two screws that securethe PCB to the front panel.7.3 Unsolder the wires at the LED PCB,make a note of the wiring configuration,and remove the board from the unit.8. LED PCB Replacement8.1 Place the LED

37、 PCB into place on thefront panel.8.2 Secure the PCB to the front panel.8.3 Resolder the wires to the LED PCB.Note: Refer to Figure 1 for the followingprocedures.1. Top Cover Removal1.1 Remove the four screws that securethe top cover to the unit.1.2 Slide the top cover towards the back ofthe unit an

38、d lift it off.2. Top Cover Replacement2.1 Place the top cover on to the unit andslide it under the front panel lip.2.2 Secure the top cover to the unit.3. Amplifier PCB Removal3.1 Perform procedure 1.3.2 Disconnect the wire harness, inputcable, and the two wires going to thethermal cutout.3.3 Remove

39、 the six screws (2B) located onthe side of the unit between the heat sinkfins (see Figure 2).3.4 Carefully pry the PCB inward towardsthe power transformer (the PCB is stuck tothe chassis by the heat sinking compound)and lift the board out of the unit.4. Amplifier PCB Replacement4.1 Slide the PCB int

40、o place. Be sure thereis sufficient heat sinking compound on thePCBs heat sink.4.2 Align the six screws that secure thePCB into place and secure the PCB to thechassis.4.3 Connect the wire harness, thermalcutout wires, and the input cable to thePCB.5. Front Panel Removal5.1 Perform procedure 1.1800 P

41、ower Amplifier81800 Power AmplifierDISASSEMBLY/ASSEMBLY PROCEDURES13. Rear Panel Removal13.1 Perform procedure 1.13.2 Locate and remove the four screwssecuring the rear panel and the rear panelbracket to the unit.Note: One of the screws holds the groundwires to the chassis. Take care not to losethe

42、nuts that secure this screw and thewires.14. Rear Panel Replacement14.1 Align the rear panel with the chassis.14.2 Secure the rear panel to the chassis.Be sure to use the rear panel bracket onthe bottom of the panel.14.3 Secure the ground wires to thechassis.14.4 Perform procedure 2.9. Gain Control

43、Removal9.1 Perform procedure 5.9.2 Remove the gain control knobs.9.3 Unsolder the capacitor lead and wiresfrom the control.9.4 Remove the nut that secures thecontrol to the front panel and remove thecontrol.10. Gain Control Replacement10.1 Place the new control into the frontpanel and secure it into

44、 place.10.2 Resolder the capacitor lead and thewires to the terminals on the gain control.10.3 Perform procedure 6.11. Power Switch Removal11.1 Perform procedure 5.11.2 Remove the wires on the rear of thepower switch.11.3 Remove the nut securing the switchto the front panel and remove the switch.12.

45、 Power Switch Replacement12.1 Place the new power switch into thefront panel and secure it in place.12.2 Reconnect the wires on the rear ofthe switch.12.3 Perform procedure 6.Note: Refer to Figure 6 for the followingprocedures.Note: Refer to Figures 3, and 4 for thefollowing procedures.9TEST PROCEDU

46、RES1. Bias Adjustment Setup and Procedure1.1 Locate the -85V negative terminalfound on the capacitor (C4). See Figure 1for the location of C4.Note: The 1801 and very early 1800s hadtwo lugs on the caps. One with two or threewires and one single wire. The later pro-duction 1800 had three lugs on the

47、capaci-tor. Either way the lug with the two or threewires is the lug to disconnect from thecapacitor. All other lugs remain.1.2 Remove the lug with two or three wiresconnected to it.1.3 Connect a 0-200mA meter betweenthe disconnected lug and the - terminal onthe capacitor C4.1.4 Disconnect the PCB t

48、hat is not beingtested by unplugging the multiple pinconnector.1.5 Turn the amplifier on with no inputsignal applied and adjust the bias pot (R13)for 90mA with the board cold.Note: The PCB must be removed fromthe chassis for the bias to be adjusted.2. Frequency Response Procedure2.1 Apply a 1Vrms, 1

49、kHz signal to theinput.2.2 Reference a dB meter to the output.2.3 Check the response from 20Hz to20kHz. The response should not exceed 1dB. Refer to the response specification onpage 2.3. DC Offset Procedure3.1 With no signal applied measure the DCoffset at the output. It should measure250mV or less

50、.4. Power Output Procedure4.1 Connect an 8 ohm, 250 Watt load tothe output.4.2 Apply a 1.75Vrms, 1kHz signal to theinput.4.3 Turn the gain controls up to the pointwhere the clipping LEDs just begin to light up and check the output for 250watts.4.4 Repeat the steps above for a 4 ohmload. The output m