Jvc-RX-7042-S-Service-Manual电路原理图.pdf

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1、SERVICE MANUALCOPYRIGHT 2004 VICTOR COMPANY OF JAPAN, LIMITEDNo.MB1722004/3AUDIO/VIDEO CONTROL RECEIVERMB17220043RX-7042STABLE OF CONTENTS1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32

2、 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-53 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-

3、64 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-135 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4、. . . . 1-14Area suffixJ - U.S.A.C - Canada1-2 (No.MB172)SPECIFICATIONDesigns & specifications are subject to change without notice.AmplifierOutput PowerAt StereoOperationFront ch 130 W per channel, min. RMS, driven into 8 , 20 Hz to 20 kHz, with no more than 0.08% total harmonicdistortion.At Surrou

5、ndOperationFront ch 130 W per channel, min. RMS, driven into 8 at 1 kHz, with no more than 0.8% total harmonic distortion.Center ch 130 W, min. RMS, driven into 8 at 1 kHz, with no more than 0.8% total harmonic distortion.Surround ch 130 W per channel, min. RMS, driven into 8 at 1 kHz, with no more

6、than 0.8% total harmonic distortion.Surround Back ch 130 W, min. RMS, driven into 8 at 1 kHz, with no more than 0.8% total harmonic distortion.AudioAudio Input Sensitivity/Impedance (1 kHz)DVD IN, VCR IN, TV SOUND/DBS IN : 200 mV/47 kCD IN, TAPE/CDR IN : 200 mV/47 kAudio Input(DIGITAL IN)*Coaxial DI

7、GITAL 1 (DVD) : 0.5 V(p-p)/75 Optical DIGITAL 2 (CD), DIGITAL 3 (TV), DIGITAL 4 (CDR) : -21 dBm to -15 dBm (660 nm 30 nm)* Corresponding to Linear PCM, Dolby Digital, and DTS (with sampling frequency-32 kHz, 44.1 kHz, 48 kHz).Audio Output Level SUBWOOFER OUT : 1 VRecording Output Level VCR OUT, TAPE

8、/CDR OUT : 200 mVDigital Output Optical DIGITAL OUT Signal wave length : 660 nmOutput level : -21 dBm to -15 dBmSignal-to-Noise Ratio(66 IHF/78 IHF)DVD IN, VCR IN, TV SOUND/DBS IN : 87 dB/80 dBCD IN, TAPE/CDR IN : 87 dB/80 dBFrequency Response (8 ) DVD IN, VCR IN, TV SOUND/DBS IN : 20 Hz to 100 kHz

9、(+1 dB, -3 dB)CD IN, TAPE/CDR IN : 20 Hz to 100 kHz (+1 dB, -3 dB)Bass Boost +6 dB 1.0 dB at 100 HzEqualization 63 Hz, 250 Hz, 1 kHz, 4 kHz, 16 kHz (8 dB) (in 2 dB steps)VideoVideo Input Sensitivity/Impedance Composite Video : DVD IN, VCR IN, TV SOUND/DBS IN 1 V(p-p)/75 S-video : DVD IN, VCR IN, TV

10、SOUND/DBS IN (Y: luminance) : 1 V(p-p)/75 (C: chrominance, burst) : 0.286 V(p-p)/75 Component Video DVD IN, DBS (VCR) IN : DVD IN, DBS (VCR) IN (Y: luminance) : 1 V(p-p)/75 (PB/PR) : 0.7 V(p-p)/75 Video Output Level Composite Video : VCR OUT, MONITOR OUT 1 V(p-p)/75 S-video : VCR OUT, MONITOR OUT (Y

11、: luminance) : 1 V(p-p)/75 (C: chrominance, burst) : 0.286 V(p-p)/75 Component Video : MONITOR OUT (Y: luminance) : 1 V(p-p)/75 (PB/PR) : 0.7 V(p-p)/75 Synchronization NegativeSignal-to-Noise Ratio 45 dBFM tuner (IHF)Tuning Range 87.5 MHz to 108.0 MHzUsable Sensitivity Monaural : 12.8 dBf (1.2 V/75

12、)50 dB Quieting Sensitivity Monaural : 16.0 dBf (1.7 V/75 )Stereo : 37.5 dBf (20.5 V/75 )Stereo Separation at OUT (REC) 35 dB at 1 kHzAM tunerTuning Range 530 kHz to 1 710 kHzGeneralPower Requirements AC 120V , 60 HzPower Consumption 320 W/440 VA (at operation), 2 W (in standby mode)Dimensions (W H

13、D) 435 mm 157 mm 425 mm (17 3/16 in. 6 3/16 in. 16 3/4 in.)Mass 12.1 kg (26.7 lbs)(No.MB172)1-3SECTION 1PRECAUTION1.1 Safety Precautions(1) This design of this product contains special hardware andmany circuits and components specially for safety purpos-es. For continued protection, no changes shoul

14、d be madeto the original design unless authorized in writing by themanufacturer. Replacement parts must be identical tothose used in the original circuits. Services should be per-formed by qualified personnel only.(2) Alterations of the design or circuitry of the product shouldnot be made. Any desig

15、n alterations of the product shouldnot be made. Any design alterations or additions will voidthe manufacturers warranty and will further relieve themanufacture of responsibility for personal injury or propertydamage resulting therefrom.(3) Many electrical and mechanical parts in the products havespe

16、cial safety-related characteristics. These characteris-tics are often not evident from visual inspection nor can theprotection afforded by them necessarily be obtained by us-ing replacement components rated for higher voltage, watt-age, etc. Replacement parts which have these specialsafety character

17、istics are identified in the Parts List of Ser-vice Manual. Electrical components having such featuresare identified by shading on the schematics and by ( ) onthe Parts List in the Service Manual. The use of a substitutereplacement which does not have the same safety charac-teristics as the recommen

18、ded replacement parts shown inthe Parts List of Service Manual may create shock, fire, orother hazards.(4) The leads in the products are routed and dressed with ties,clamps, tubings, barriers and the like to be separated fromlive parts, high temperature parts, moving parts and/orsharp edges for the

19、prevention of electric shock and firehazard. When service is required, the original lead routingand dress should be observed, and it should be confirmedthat they have been returned to normal, after reassem-bling.(5) Leakage shock hazard testingAfter reassembling the product, always perform an isola-

20、tion check on the exposed metal parts of the product (an-tenna terminals, knobs, metal cabinet, screw heads,headphone jack, control shafts, etc.) to be sure the productis safe to operate without danger of electrical shock.Do notuse a line isolation transformer during this check. Plug the AC line cor

21、d directly into the AC outlet. Using a“Leakage Current Tester“, measure the leakage currentfrom each exposed metal parts of the cabinet, particular-ly any exposed metal part having a return path to thechassis, to a known good earth ground. Any leakage cur-rent must not exceed 0.5mA AC (r.m.s.). Alte

22、rnate check methodPlug the AC line cord directly into the AC outlet. Use anAC voltmeter having, 1,000 per volt or more sensitivityin the following manner. Connect a 1,500 10W resistorparalleled by a 0.15F AC-type capacitor between an ex-posed metal part and a known good earth ground.Measure the AC v

23、oltage across the resistor with the ACvoltmeter. Move the resistor connection to each exposed metalpart, particularly any exposed metal part having a returnpath to the chassis, and measure the AC voltage acrossthe resistor. Now, reverse the plug in the AC outlet andrepeat each measurement. Voltage m

24、easured any mustnot exceed 0.75 V AC (r.m.s.). This corresponds to 0.5mA AC (r.m.s.). 1.2 Warning(1) This equipment has been designed and manufactured tomeet international safety standards.(2) It is the legal responsibility of the repairer to ensure thatthese safety standards are maintained.(3) Repa

25、irs must be made in accordance with the relevantsafety standards.(4) It is essential that safety critical components are replacedby approved parts.(5) If mains voltage selector is provided, check setting for localvoltage.1.3 CautionBurrs formed during molding may be left over on some partsof the cha

26、ssis. Therefore, pay attention to such burrs in the case of pre-forming repair of this system.1.4 Critical parts for safetyIn regard with component parts appearing on the silk-screenprinted side (parts side) of the PWB diagrams, the parts that areprinted over with black such as the resistor ( ), dio

27、de ( )and ICP ( ) or identified by the “ “ mark nearby are criticalfor safety. When replacing them, be sure to use the parts of thesame type and rating as specified by the manufacturer. (This regulation dose not Except the J and C version)Good earth groundPlace this probe on each exposedmetal part.A

28、C VOLTMETER(Having 1000 ohms/volts,or more sensitivity)1500 10W0.15 F AC TYPE1-4 (No.MB172)1.5 Importance administering point on the safetyCaution: For continued protection against risk offire, replace only with same type 6.3A/125V forF1, 2A/125V for F61 and F62.This symbol specifies type of fast op

29、erating fuse.Precaution: Pour eviter risques de feux, remplacezle fusible de surete de F1 comme le meme typeque 6.3A/125V, et 2A/125V pour F61 et F62.Ce sont des fusibles suretes qui functionnes rapide.Power trans 1 boardPower / fuse board6.3A-125VF12A-125VF612A-125VF62(No.MB172)1-5SECTION 2SPECIFIC

30、 SERVICE INSTRUCTIONSThis service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.1-6 (No.MB172)SECTION 3DISASSEMBLY3.1 Removing the top cover (See Fig.1)(1) From the right and left sides of the main body, remove thefour screws A attaching the top cover.(2) From the back side of the main body

31、, remove the threescrews B attaching the top cover.(3) Remove the top cover in the direction of the arrow 2 whileextending the lower sections of the top cover in the direc-tion of the arrow 1.Fig.13.2 Removing the front panel assembly (See Figs.2 and 3) Prior to performing the following procedures,

32、remove the topcover.(1) Disconnect the card wire from the connector CN400 on themicon board. (See Fig.2)(2) Disconnect the card wire from the connector CN402 on thepower supply board. (See Fig.2)(3) Remove the tie band and wire protection board fixing thecard wire. (See Fig.2)(4) Remove the three sc

33、rews C attaching the front panel as-sembly. (See Fig.2)(5) From the bottom side of the main body, remove the fourscrews D attaching the front panel assembly. (See Fig.3)(6) Remove the front panel assembly in the direction of the ar-row. (See Fig.3)Fig.2Fig.3Top coverA211BAC CCFront panel assemblyCar

34、d wireCN402Tie bandWireprotectionboardCN400MiconboardPowersupplyboardCard wireDDFront panel assembly(No.MB172)1-73.3 Removing the rear panel (See Fig.4) Prior to performing the following procedures, remove the topcover.(1) From the back side of the main body, remove the strain re-lief from the rear

35、panel in the direction of the arrow.(2) Remove the twenty-nine screws E, two screws F and threescrews G attaching the rear panel.Fig.43.4 Removing the I/O board (See Fig.5) Prior to performing the following procedures, remove the topcover and rear panel.(1) Remove the two plastic rivets in the direc

36、tion of the arrowfrom the top side of the main body, remove the stopperboards in the direction of the arrow.(2) Remove the tie bands bundling the wires.(3) Disconnect the wire from the connector CN722 on the cen-ter board.(4) Disconnect the wire from the connector CN714 on the frontboard(L).(5) Disc

37、onnect the wire from the connector CN717 on the sur-round back board.(6) Disconnect the wire from the connector CN719 on the frontboard(R).(7) Disconnect the wire from the connector CN723 on the mainboard.(8) Disconnect the connectors (CN205, CN381, CN501) onthe I/O board in an upward direction.Fig.

38、53.5 Removing the tuner, DSP board, audio board, video board and S-video board (See Fig.6) Prior to performing the following procedures, remove the topcover, rear panel and I/O board.(1) Disconnect the card wire from the connector CN314 on theaudio board from the top side of the main body, take out

39、thetuner.(2) Disconnect the DSP board from the connector CN601 onthe micon board.(3) Disconnect the audio board from the connectors (CN101,CN303) on the micon board.(4) Disconnect the video board from the connector CN201 onthe micon board.(5) Disconnect the S-video board from the connector CN241on t

40、he micon board.Fig.6Strain reliefEGE FGEEE GRear panelCN381CN205CN501Plastic rivetPlasticrivetStopperboardStopper boardTiebandCenter boardTiebandsFront board(L)Surround boardFront board(R)CN719CN717 CN714CN722CN723MainboardI/O boardCN314TunerAudio boardCard wireCN601DSP boardCN303CN101Video boardS-v

41、ideo boardCN201 CN241Micon board1-8 (No.MB172)3.6 Removing the micon board (See Fig.7) Prior to performing the following procedures, remove the topcover, rear panel, I/O board, tuner, DSP board, audio board,video board and S-video board.(1) From the top side of the main body, disconnect the cardwire

42、 from the connector CN400 on the micon board.(2) Disconnect the relay board from the connectors CN81 onthe micon board.(3) Disconnect the parallel wire from the connectors CN931and CN932 on the micon board.(4) Disconnect the parallel wire from the connector CN831 onthe main board.(5) Remove the thre

43、e screws H attaching the micon board.(6) Remove the three screws J attaching the transistors(Q931, Q941, Q981) to the chassis base.(7) Loosen the screw K attaching the micon board.Fig.73.7 Removing the speaker board (See Fig.8) Prior to performing the following procedures, remove the topcover and re

44、ar panel.(1) From the top side of the main body, remove the tie bandbundling the wires.(2) Disconnect the wires from the connectors (CN813, CN814)on the main board.(3) Disconnect the parallel wire from the connectors (CN931,CN932) on the micon board.(4) Take out the speaker board in the direction of

45、 the arrow.Fig.8CN400Micon boardRelayboardCN81Card wireCN931CN932HHHJTransistors(Q931,Q941,Q981)ChassisbaseKCN831Main boardTie bandCN813Main boardSpeaker boardCN814CN931CN932Micon board(No.MB172)1-93.8 Removing the main board (See Fig.9) Prior to performing the following procedures, remove the topco

46、ver.(1) From the top side of the main body, remove the tie bandsbundling the wires.(2) Remove the tie band and wire protection board bundlingthe card wire.(3) Disconnect the wire from the connector CN811 on the pow-er transformer board 1.(4) Disconnect the relay board from the connectors (CN71,CN81)

47、 on the power supply board and micon board.(5) Disconnect the parallel wires from the connectors (CN831,CN881) on the main board.(6) Disconnect the wires from the connectors (CN723, CN813,CN814) on the main board.(7) Disconnect the wire from the connector CN722 on the cen-ter board.(8) Disconnect th

48、e wire from the connector CN714 on the frontboard(L).(9) Disconnect the wire from the connector CN717 on the sur-round back board.(10) Disconnect the wire from the connector CN719 on the frontboard(R).(11) Remove the screw K, four screws L, two screws M and twoscrews N attaching the main board.(12)

49、Take out the main board.Fig.93.9 Removing the heat sink (See Figs.10 and 11) Prior to performing the following procedures, remove the topcover and main board.(1) From the reverse side of the main board, remove the twoscrews P attaching the main board to the heat sink. (SeeFig.10)(2) Disconnect the connectors (CN701-CN706) on the mainboard, remove the main board. (See Fig.10)(3) Remove the twelve screws Q attaching the heat sink. (SeeFig.11)Fig.10Fig.11Tie bandW