Bose-550-rec-sm维修电路原理图.pdf

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1、Model 550AM/FM Stereo ReceiverPart Number 112429 REV 01Service ManualRadioFans.CN 收音机爱 好者资料库2ContentsSafety Information. 3Electrostatic Discharge Sensitive (ESDS) Device Handling . 4Specifications.5-6Technical Description . 7Disassembly/Assembly Procedures . 8-10Figure 1. Antenna Placement Diagram .

2、 10Test Procedures . 11-14Figure 2. AM/FM Adjustment Location . 12Figure 3. Amp Adjustment Location . 14Figure 4. Block Diagram. 15Figure 5. Wiring Diagram . 16Figure 6. Main PCB Layout . 17Figure 7. PCB Layout. 18Figure 8. Exploded View . 19Figure 9. Dial String Diagram. 20Figure 10. Pinout Locatio

3、n Diagram. 21Part List Notes. 22Part List. 23-30Voltage Conversion Instructions . 31RadioFans.CN 收音机爱 好者资料库3SAFETY INFORMATION 1. Parts that have special safety characteristics are identified by the symbol on schematics or by special notes on the parts list. Use only replacement parts that have crit

4、ical characteristics recommended by the manufacturer. 2. Make leakage current or resistance measurements to determine that exposed parts are acceptably insulated from the supply circuit before returning the unit to the customer. Use the following checks to perform these measurements:A. Leakage Curre

5、nt 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 or a meteringsystem that complies with American National Standards Institute (ANSI)C101.1 “Leakage Current for A

6、ppliances” 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,conduit, etc.) to all exposed metal parts of the unit (antennas, handle bracket,metal cabinet, screwheads, metallic o

7、verlays, 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 powercord plug in the outlet and repeat test. ANY MEASUREMENTS NOT WITHINTHE LIMITS SPECIFIED HEREIN INDICATE A PO

8、TENTIAL 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 between the two prongs of the plug. (2) Turn on the power switch of the unit. (3) Measure the resistance with an ohmm

9、eter 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 5.2 Megohms. When there is no return path to the chassis, the reading must be “infinite”. If it is not within t

10、he 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 (ESDS)DEVICE HANDLINGThis unit contains ESDS devices. We recommend the following precautions when repairing,replacin

11、g or transporting 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 e

12、dges only. 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, bubble wrapor plastic trays.CAUTION: THE 550 RECEIVER CONTAINS NO USER-SERVICEABLE PARTS. TO PRE-VENT WARRANTY I

13、NFRACTIONS, REFER SERVICING TO WARRANTY SERVICE STA-TIONS OR FACTORY SERVICE.5SPECIFICATIONSPhono Overload:100 mVLoudness Contour:+8 dB 100 Hz (2 dB)+6 dB 12kHz (2 dB)AM Tuner:20 dB Usable SensitivityAdjacent Channel SelectivityTotal DistortionImage RejectionIF RejectionSignal to Noise Ratio350 uV (

14、ferrite loopstick)35 dB.9% (400 Hz 30%Modulation)37 dB45 dB40 dB FM Tuner:IHF Usable Sensitivity50 dB Quieting SensitivityFrequency ResponseSignal to Noise Ratio 65 dBfTHD 65 dBfCapture RatioAlternate Channel SensitivitySpurious Response RejectionImage RejectionAM RejectionStereo Separation, 1kHz2.0

15、 uV/11.25 dBf (Mono)3.5 uV/16.11 dBf (Stereo)3.8 uV/16.82 dBf (Mono)35 uV/37.27 dBf (Stereo)30 Hz - 15kHz, +1.0 dB - 3.0 dB65 dB (Mono)60 dB (stereo).25% (Mono).50% (Stereo)1.9 dB60 dB80 dB65 dB50 dB40 dBChannel Separation:AUX. and TapePhono60 dB 1kHz (at Tape - Out)55 dB 1kHz (at Tape - Out)6SPECIF

16、ICATIONSInput SensitivityImpedance: Capacitance:Aux. and TapePhono150 mV/ 50k Ohm2.75 mV/ 47k Ohm, 150 pFSource and RoomCompensation Controls:Low FilterLow Frequency ControlNarrow PositionWide PositionHigh Frequency Control-3 dB 100Hz-7 dB max. 20Hz8 dB 140Hz (center frequency)1 dB 20Hz and 1kHz3 dB

17、 350Hz8 dB 50Hz8 dB 15kHz3 dB 2.2kHzFrequency Response:20 Hz to 20 kHzPhono RIAA0.5 dB0.5 dBAmplifier PowerOutput:40 Watts per Channel minimumRMS continuous power 8Ohms, THD .3%20Hz to 20kHzIHF Power Bandwidth:20Hz to 20kHzboth channels driven THD .19%IntermodulationDistortion:.09% IHF 60 Hz/7kHz 4:

18、1 mixed at rated outputSignal to Noise Ratio:AmplifierPhono87 dB A- weighted (below rated output) inputs shorted91 dB A- weighted (below rated output) min. volume76 dB A- weighted (below rated output) inputs shortedPower Requirements:120 Volts AC 60 Hz (USA model)220 Volts AC 50-60 Hz (export model)

19、Power Consumption:360 Watts at rated power AC Outlets:1 switched, 1 unswitched400 watts max.Dimensions:18 1/4 x 5 3/4 x 12 1/4 46.6 (w) x 14.6 (h) x 31.1 (d) cmWeight:15 1/2 lbs7 Kg7The Model 550 AM/FM Stereo Receiver features a high quality AM/FM Stereo tuner and adirect-coupled amplifier with 40 w

20、atts of RMS power per channel.The Model 550 includes a built-in 901 Series IV equalizer, that provides extra value andconvenience to present owners and future purchasers of Bose 901 loudspeakers. The built-inequalizer can be switched into the circuit when playing Bose 901 Series III or Series IV spe

21、ak-ers. You can pre-set the Model 550 via the rear panel switches for various combinations ofloudspeakers. This provides correct equqlization when switching from one pair of speakers tothe other.The receiver incorporates Source and Room Compensation Controls unique to Bose electronicequipment. These

22、 controls allow you to compensate more accurately for problems in roomacoustics and recordings. The result is greater realism and enjoyment.TECHNICAL DESCRIPTION8DISASSEMBLY/ASSEMBLY PROCEDURESNote: Numbers in parentheses corre-spond to the callouts in Figure 8.1. Top Cover Removal1.1 Remove the 4 s

23、crews (A-14) locatedon each side of the unit.1.2 Lift the top cover (A-2) off of the unit.2. Top Cover Replacement2.1 Place the top cover onto the top of theunit.2.2 Secure the top cover to the unit.3. Bottom Cover Removal3.1 Remove the 5 screws (L-13) thatsecure the bottom cover (A-3) to the unit.3

24、.2 Remove bottom cover.4. Bottom Cover Replacement4.1 Place the bottom cover onto the unit.4.2 Secure the bottom cover to the unit.5. Front Panel Removal5.1 Perform procedures 1 and 3.5.2 Remove the volume, tuning, and slidepot knobs.5.3 Locate and remove the 3 screws (L-3)that secure the front pane

25、l (A-1) to the topfront of the unit.5.4 Unclip the 4 plastic clips located at thebottom of the front panel and remove thepanel from the unit.6. Front Panel Replacement6.1 Place the front panel onto the unit andclip the bottom of the front panel into place.6.2 Secure the top of the front panel andrep

26、lace the knobs.7. 901 EQ PC Board RemovalNote: There is no callout on Figure 8. forthe EQ board. The 901 EQ board is locatedunder the dial lamp and behind the slidepots.7.1 Perform procedures 1 and 3.7.2 Using a pair of pliers, unclip the threeplastic standoffs holding the board in place.8. 901 EQ P

27、C Board Replacement8.1 Align the standoffs over the holes inthe main PC board. Push the 901 EQboard into place.9. Slide Pot Removal9.1 Perform procedures 5 and 7.9.2 Unscrew the two screws (L-12) thatsecure each of the slide pots to the front ofthe unit.9.3 Remove the slide pots through thebottom of

28、 the unit.10. Slide Pot Replacement10.1 Guide the slide pot assembly throughthe bottom of the unit and place it into thefront of the unit.10.2 Secure the slide pots to the unit.9DISASSEMBLY/ASSEMBLY PROCEDURES11. Dial Lamp Assembly Removal11.1 Perform procedure 1.11.2 Carefully slide the dial lamp P

29、C boardto the left (with the unit facing you) and liftthe board off of the clips.11.3 Lift the board up towards the top ofthe unit and replace any defective bulbs.12. Dial Lamp Assembly Replacement12.1 Position the dial lamp PC board overthe locking clips.12.2 While aligning the clips with the holes

30、in the PC board, carefully slide the board tothe right to secure it to the lamp housing.13. Selector Lamp Assembly Removal13.1 Perform procedure 7.13.2 Remove the screw (L-1) securing thePC board to the front housing.13.3 Unclip the ends of the board andremove it from the housing.13.4 Replace any bu

31、lbs that are defective.14. Selector Lamp Assembly Replace-ment14.1 Place the PC board into the housingand clip it into place.14.2 Secure the board to the housing.15. Meter Lamp Assembly Removal15.1 Perform procedure 1.15.2 Remove the screw (L-1) securing themeter lamp PC board to the housing.15.3 Cu

32、t any tie wraps needed and re-move the PC board from the housing.15.4 Replace any defective bulbs.16. Meter Lamp Assembly Replacement16.1 Place the PC board into the housingand secure it to the housing.16.2 Replace any tie wraps that had beenremoved.17. Volume Control Removal17.1 Perform procedure 5

33、.17.2 Remove the nut securing the volumecontrol to the front housing and remove thecontrol from the rear of the housing.18. Volume Control Replacement18.1 Place the volume control through therear of the front housing.18.2 Secure the volume control to thefront housing.19. Power Switch Removal19.1 Per

34、form procedure 5.19.2 Remove the two screws securing thepower switch to the front assembly.19.3 Remove the power switch through the bottom of the unit.20. Power Switch Replacement20.1 Place the power switch into the frontassembly.20.2 Secure the power switch to the frontassembly.10TEST PROCEDURES1.

35、AM Tuner Adjustment ProcedureNote: Refer to the antenna placementdiagram Figure 1.1.1 Connect an AM signal generator to anAM loop antenna. Set the frequency ac-cording to the AM alignment procedurelisted below.1.2 Connect a voltmeter to the tape outputjacks on the rear panel.1.3 Refer to the adjustm

36、ent location chart(Figure 2.) for the location of the tuningcoils called out in the AM alignment proce-dure.2. FM/MPX Tuner Adjustment2.1 Connect an FM signal generator to theantenna terminals on the rear panel.2.2 Connect a voltmeter to the tape outputjacks on the rear panel.2.3 Refer to the adjust

37、ment location chart(Figure 2.) for the location of the tuningcoils called out in the FM/MPX alignmentprocedure.2.4 Perform the tests listed on the nextpage for the FM and MPX sections.AM Alignment Procedure?STANDARDSIGNALGENERATORSTANDARDSIGNALGENERATOR60cmTESTLOOPBARANTENNA(PLAN VIEW)(SIDE VIEW)?Fi

38、gure 1. Antenna Placement Diagram11TEST PROCEDURESMPX Alignment ProcedureFM Alignment Procedure12Figure 2. AM/FM Adjustment Location13TEST PROCEDURES3. Loudness Control ProcedureNote: Use the following control settings.Slide pots centered, speaker A switchselected with the output connected to an 8oh

39、m load, all switches out except for theaux switch.3.1 Apply a 100Hz signal at 1Volt to theaux input.3.2 Rotate the volume control until 1.5Vrms is measured at the output.3.3 Reference a dB meter to the output.3.4 Push the loudness switch IN. Thereshould be a +8dB change in response atthe output.3.5

40、Change the signal to 12kHz and repeatstep 3.3 and 3.4. There should be a + 6dBchange in response at the output.4. Low Filter Procedure4.1 Perform procedure 3.1, 3.2, and 3.3.4.2 Push the low filter switch IN. Thereshould be a -3dB change in response at theoutput.4.3 Change the input frequency to 20H

41、zand reference a dB meter to the output.4.4 Push the low filter switch IN. Thereshould be a -7dB change in response at theoutput. 5. Low Frequency Control Procedure5.1 Apply a 140Hz signal at 1Volt to theaux input.5.2 Rotate the volume control until 1.5Vrms is measured at the output.5.4 Slide the co

42、ntrol from one side to theother. There should be a + 8dB and -8dBchange in response ( 1dB) from thecenter.5.5 Push the wide/narrow switch IN.Change the frequency to 350Hz. With thelow frequency control centered reference adB meter to the output.5.6 Slide the control from side to side.There should be

43、 a +3dB and -3dB changein response (1dB) from the center.6. High Frequency Procedure6.1 Apply a 15kHz signal at 1Volt to theaux input.6.2 Reference a dB meter to the output.6.3 Slide the high frequency control fromside to side. There should be a +8dB and -8dB change in response (1dB) at theoutput.6.

44、4 Change the input signal to 2.2kHz.Slide the control from side to side. Thereshould be a +3dB and -3dB change inresponse (1dB) at the output.7. 901 EQ Response Procedure7.1 Apply a 250Hz signal 1Volt to the auxinput. Reference a dB meter to the output.7.2 Switch the EQ switch located on therear pan

45、el from the other position to the901 position. There should be a -1dBchange in response at the output.5.3 Reference a dB meter to the outputwith the low frequency control centered andthe wide/narrow switch in the OUT position.14TEST PROCEDURESFigure 3. Amp Adjustment Location8. Amplifier Adjustment

46、ProcedureNote: Preheat the unit for about 20 minutesprior to performing the following procedure.8.1 Connect a DC voltmeter to the testpoints TP 501-502 (across R536) for theright channel and at TP 503-504 (acrossR537) for the left channel see Figure3. forthe TP locations.8.2 Connect the output to an

47、 8 ohm load,volume set to the minimum position, with nosignal applied.8.3 Adjust VR452 for the right channel andVR451 for the left channel to a setting of7mV at the test points.901 Response ChartFrequency Output Tolerence 40Hz+16dB2dB250Hz0dBReference-700Hz -7.0dB2dB10kHz+16dB2dB14kHz +21dB2dB7.3 Re

48、ference a dB meter to the output.7.4 Check the response using the chartbelow.15Figure 4. Block DiagramLeft Channel ( Same as Right Channel)Figure 5. Wiring Diagram1617Figure 6. Main PCB Layout18Figure 7. PCB LayoutFigure 8. Exploded View1920Figure 9. Dial String Diagram21Figure 10. Pinout Location D

49、iagram22PART LIST NOTES1. This part is not normally available from Customer Service. Approval from the Field ServiceManager is required before ordering.2. The individual parts located on the PCBs are listed in the Electrical Parts Lists.3. This part is critical for safety purposes. Failure to use a

50、substitute replacement withthe same safety characteristics as the recommended replacement part might create shock, fireand/or other hazards.23PART LISTMain Assembly (see Figure 8)ItemNumberDescriptionPartNumberNoteA-1Front Panel Assembly112889A-2Cabinet112344A-3Bottom Plate112890A-4Dial Window112345