JVC-CXJT8-cs-sm维修电路原理图.pdf

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1、RadioFans.CN 收音机爱 好者资料库 18 CX-JT8 SECTION 4 TEST MODE COLD RESET The cold reset clears all data including preset data stored in the RAM to initial conditions. Execute this mode when returning the set to the customer. Procedure: 1.Press the POWER key to turn the power ON. 2.Press three keys ofx, ENTE

2、R and POWER simultaneously. 3.The message “RESET” is displayed on the fluorescent indicator tube momentarily, then becomes standby states. TUNER STEP CHANGE-OVER (Except AEP, UK and CIS models) A step of AM channels can be changed over between 9 kHz and 10 kHz. Procedure: 1.Press the POWER key to tu

3、rn the power ON. 2.Press the TUNER BAND key to select “AM”. 3.Press the POWER key to turn the power OFF. 4.Press two keys of ENTER and POWER simultaneously. 5.The message “9K STEP” or “10K STEP” is displayed on the fluorescent indicator tube, and thus the channel step is changed over. CD SHIP MODE T

4、his mode moves the optical pick-up to the position durable to vibration. Use this mode when returning the set to the customer after repair. Procedure: 1.Press the POWER key to turn the power ON. 2.Press the CD key to select “CD”. 3.Press two keys of CD and POWER simultaneously. 4.The message “LOCK”

5、is displayed on the fluorescent indicator tube, and the CD ship mode is set. CHANGE-OVER FUNCTION OF MD/VIDEO This mode is used to enable function of external input to change over between MD and VIDEO. Procedure: 1.Set to standby state. 2.Press two keys of MD VIDEO and POWER simultaneously. 3.The me

6、ssage “MD” or “VIDEO”is displayed on the fluorescent indicator tube, and the function of external input is changed over. CD TRAY LOCK MODE This mode is used to unable to take sample disc out of tray in the shop. Procedure: 1.Press the POWER key to turn the power ON. 2.Press the CD key to select “CD”

7、. 3.While pressing thexkey, press theZkey for 5 seconds. 4.The message “LOCKED” is displayed on the fluorescent indicator tube and the tray is locked. (Even if pressing theZkey, the message “LOCKED” is displayed on the fluorescent indicator tube and the tray is locked) 5.To release from this mode, w

8、hile pressing thexkey, press theZkey for 5 seconds. 6.The message “UNLOCKED” is displayed on the fluorescent indicator tube and the tray is unlocked. AMP TEST MODE This mode is used to set the parameter of AMP IC for adjustment of tone quality and VACS level and display VACS status. Procedure: 1.Pre

9、ss the POWER key to turn the power ON. 2.Press three keys ofx, HEAVY and HIP POP simultaneously. 3.When the AMP test mode is activated, the message “AMP TEST” is displayed on the fluorescent indicator tube momentarily. 4.Press two keys of HEAVY and DISC DIRECT PLAY 2 simultaneously, mode is changed

10、over to parameter setting of AMP IC and display of VACS status. 5.When the VACS ON, the message “V2255255” is displayed on the fluorescent indicator tube, and when the VACS OFF, the message “2255255” is displayed on the fluorescent indicator tube. 6.Press the VOCAL key, DBFB ON/OFF is changed over.

11、7.Press the ENTER key, surround ON/OFF is changed over. 8.Press the MANUAL key, EQ band is changed over to LOW, MID or HIGH. 9.Press the HIP POP and TECHNO key, EQ curve adjustment value is changed over between 8dB to +8dB. 10. To release from this mode, press two keys of HEAVY and TECHNO simultaneo

12、usly. )( RadioFans.CN 收音机爱 好者资料库 19 CX-JT8 AGING MODE This mode can be used for operation check of CD section and tape deck section. CD section and tape deck section work in parallel. If an error occurred: The aging operation stops only an error occurred sections and display then status. If no error

13、 occurs: The aging operation continues repeatedly. Procedure: 1.Press the POWER key to turn the power ON. 2.Press the CD key to select “CD”. 3.Set disc on the tray and set tape into the deck. 4.Set the “ALL DISCS” mode and “REV OFF” mode. 5.Press three keys ofx, HEAVY and DISC CHANGE/DISC SKIP simul

14、taneously. 6.The message “AGING” is displayed on the fluorescent indicator tube momentarily, then aging operations of CD and tape are started at the same time. 7.To release from this mode, operate the “COLD RESET”. 1. Display at the Aging Mode Display operating state of CD section and tape deck sect

15、ion alternately. If an error occurred, stop display which that section. 2. CD Section The sequence during the aging mode is following as below. Display at the aging mode is the same as the normal operation. Aging mode sequence (CD section) : Start (from disc 1) Disc chucking TOC read Play first trac

16、k for 2 seconds Play last track for 2 seconds EX-change open/close Open the disc tray Disc skip Close the tray Change the next disc. 3. Tape Deck Section The sequence during the aging mode is following as below. If an error occurred, stop display that step. Aging mode sequence (tape deck section) :

17、Rewind the tape A and B “AAG-1 or 2” Shut off FWD play the tape A “AAG-3” 2 minutes Fast forward the tape A “AAG-4” Shut off or 20 seconds REV play the tape A “AAG-5” 2 minutes Rewind the tape A “AAG-6” Shut off FWD play the tape B “BAG-3” 2 minutes Fast forward the tape B “BAG-4” Shut off or 20 sec

18、onds REV play the tape B “BAG-5” 2 minutes Rewind the tape B “BAG-6” Shut off Note: “*AG-*” is display of each step. 20 CX-JT8 GC TEST MODE This mode is used to check the fluorescent indicator tube, LED and key. Procedure: 1.Press the POWER key to turn the power ON. 2.Press three keys ofx, HEAVY and

19、 DISC DIRECT PLAY 2 simultaneously. 3.Fluorescent indicator tube and LEDs are all turned ON. 4.Press two keys of HEAVY and DISC DIRECT PLAY 2 simultaneously, mode is changed over. 5.In the key check mode, press each key, the defined key number of every each key list is displayed on the fluorescent i

20、ndicator tube. 6.In the key count check mode, “K-CNT 0” is displayed on the fluorescent indicator tube. Each time a key is pressed, “K” value increases. However, once a key is pressed, it is no longer taken into account. 7.In the headphone input check mode, connect the headphone, the message “H_P ON

21、” is displayed on the fluorescent indicator tube, and disconnect the headphone, the message “H_P OFF” is displayed on the fluorescent indicator tube. 8.In the volume check mode, turn the VOLUME knob, the display on the fluorescent indicator tube is changed over to “VOL UP”, “VOL FLAT” or “VOL DOWN”

22、MC TEST MODE This mode is used to check operations of Amplifier. Procedure: 1.Press the POWER key to turn the power ON. 2.Press three keys ofx, HEAVY and DISC DIRECT PLAY 3 simultaneously. 3.When the MC test mode is activated, the message “MC MODE” is displayed on the fluorescent indicator tube mome

23、ntarily, then VACS level is displayed on the fluorescent indicator tube. 4.Press the TECHNO key, the display on the fluorescent indicator tube is changed over to “EQ MAX”, press the MANUAL key, the display on the fluorescent indicator tube is changed over to “EQ MID”, press the HIP POP key, the disp

24、lay on the fluorescent indicator tube is changed over to “EQ MIN”, 5.Turn the VOLUME knob, the display on the fluorescent indicator tube is changed over to “VOL MAX”, “VOL MID” or “VOL MIN” 6.Press the ENTER key, VACS ON/OFF is changed over. 7.When the REC PAUSE/START key is pressed with a tape set

25、in the deck-B, the function is switched “MD” or “VIDEO” and recording starts. When themorMkey is pressed during recording, the tape is rewound back to the beginning of recording, the function is switched to “TAPE B”, then playback starts. 8.When the CD SYNC key is pressed with the test tape (AMS- 10

26、0, AMS-110A) in the deck, number of space between tunes is counted, then if AMS-110A is set, “OK” is displayed on the fluorescent indicator tube and if AMS-100 is set, “NG” is displayed on the fluorescent indicator tube. 9.To release from this mode, press the POWER key. MODEL, DESTINATION AND VERSIO

27、N DISPLAY This mode is used to check the model, destination and software version. Procedure: 1.Set to the standby state. 2.Press three keys ofx, TECHNO and HEAVY simultaneously. 3.When the model, destination and version display mode is activated, the model an destination is displayed on the fluoresc

28、ent indicator tube. 4.Press two keys of HEAVY and DISC DIRECT PLAY 2 simultaneously, mode is changed over to model and destination display mode and version display mode. 5.In the version display mode, press the DISC DIRECT PLAY 3 key, display is changed over to version display and year, month and da

29、y of the software creation display. 6.To release from this mode, press the two keys of TECHNO and HEAVY simultaneously. CD ERROR CODE DISPLAY This mode can be used for error display of CD section. Procedure: 1.Press the POWER key to turn the power ON. 2.Press the CD key to select “CD”. 3.Press three

30、 keys ofx, HEAVY and DISC DIRECT PLAY 1 simultaneously. Note: Error code is not displayed on the liquid crystal display. CD SERVICE MODE This mode can run the CD sled motor freely. Use this mode, for instance, when cleaning the optical pick-up. Procedure: 1.Press the POWER key to turn the power ON.

31、2.Press the CD key to select “CD”. 3.Press three keys ofx, HEAVY andZsimultaneously. 4.When the CD service mode is activated, the message “TRVS ON” is displayed on the fluorescent indicator tube. 5.Press theMkey, optical pick-up move to outside track and the message “SLED OUT” is displayed on the fl

32、uorescent indicator tube. 6.Press themkey, optical pick-up move to inside track and the message “SLED IN” is displayed on the fluorescent indicator tube. 7.Press the TECHNO key, traverse ON/OFF is changed over. 5 REPEAT LIMIT CANCEL Number of repeat for CD playback is 5 times when the repeat mode is

33、 “REPEAT”. This mode is used to enables CD to repeat playback for limitless times. Procedure: 1.Press the POWER key to turn the power ON. 2.Press the CD key to select “CD”. 3.Press three keys ofx, HEAVY andYsimultaneously. CX-JT8 2121 CD SECTION Note: 1.CD Block is basically designed to operate with

34、out adjustment. Therefore, check each item in order given. 2.Use YEDS-18 (3-702-101-01) unless otherwise indicated. 3.Use an oscilloscope with more than 10M impedance. 4.Clean the object lens by an applicator with neutral detergent when the signal level is low than specified value with the following

35、 checks. S-CURVE CHECK Procedure : 1.Connect an oscilloscope to TP (FE) and TP (VC). 2.Turn the power on. 3.Load a disc (YEDS-18) and actuate the focus search. (In consequence of open and close the disc tray, actuate the focus search) 4.Confirm that the oscilloscope waveform (S-curve) is symmetrical

36、 between A and B. And confirm peak to peak level within 3 0.5 Vp-p. Note: Try to measure several times to make sure than the ratio of A : B or B : A is more than 10 : 7. Take sweep time as long as possible and light up the brightness to obtain best waveform. RF LEVEL CHECK Procedure : 1.Connect an o

37、scilloscope to TP (RF) and TP (VC). 2.Turn the power on. 3.Load a disc (YEDS-18) and playback. 4.Confirm that oscilloscope waveform is clear and check if RF signal level is correct or not. BD board Oscilloscope TP(FE) TP(VC) symmetry S-curve waveform within 3 0.5Vp-p A B TP(RF) BD board oscilloscope

38、 TP(VC) Note:Clear RF signal waveform means that the shape “ ” can be clearly distinguished at the center of the waveform. Connecting Location: BD board RF signal waveform VOLT/DIV : 200mV TIME/DIV : 500ns level : 1.3 0.3Vp-p TP (VC) TP (RF) TP (FE) IC721 BD Board (Conductor side) SECTION 5 ELECTRIC

39、AL ADJUSTMENTS CX-JT8 2222 SECTION 6 DIAGRAMS 6-1.BLOCK DIAGRAM CD Section 8 7 9 10 80 79 70 LIMIT SW 20 TDO 18 10 VO3(+) FOIN 20TIN 3SPIN 7LDS 25SLIN 17 VO3() 11 VO2(+) 12 VO2() 26 VO4(+) 27 VO4() 2VO1(+) 1VO1() A C B D E F LD PD RF AMP, FOCUS/TRACKING ERROR AMP, DIGITAL SIGNAL PROCESSOR, DIGIRAL S

40、ERVO PROCESSOR, DIGITAL FILTER, D/A CONVERTER IC721 21 FDO 23 SLDO 22 SPDO 25 CONT4 A B D E F C I-V AMP DETECTOR LDPD LASER DIODE OPTICAL PICK-UP BLOCK (KSM-213DCP) 2-AXIS DEVICE (FOCUS) (TRACKING) M702 (SPINDLE) M701 (SLED) M M FOCUS/TRACKING COIL DRIVE, SPINDLE/SLED MOTOR DRIVE IC722 49 48 X701 16

41、.9344MHz S701 (LIMIT) 79 DATAIN 80 DATACK 5C2FIN 1LRSY 2ADDATA 3ADBCK 4ADLRCK 7CKIN 9CKOUT 78 RESB 99 I-LC78646/LC78684 DI 98 O-LC78646/LC78684 DO 100 O-LC78646/LC78684 CLK 5O-LC78646 CE 85 I-WRQ 86 I-CD DRF 4O-LC78646 RESET 60 DATA 59 DATACK 52 C2F 58 LRSY 57 ASDFIN 56 ASDACK 55 ASLRCK 54 16MOUT 10

42、6 76 66 53 EFLG 50 FSX/16MIN 73 CMDOUT 74 CMDIN CE FSYNC O-LC78684 CE I-LC78684 SYNC 75 CL 26MP3RES 64 DO 63 DI 62 CL 96I-CD NUMBER SENS 22 I-BU IP DOWN/ CD OPEN CLOSE 9RIN LM-R 11RESET 1O-SYS-MUTE 94O-POWER RELAY 29I-HOLD S-MUTE O-POWER HOLD 61 CE 65 *WRQ 67DRF 72CD MUTE 66*RES 4OUT1 2OUT2 M751 (LO

43、ADING) M LOADING MOTOR DRIVE IC701 MP3 DECODER IC801 SYSTEM CONTROLLER IC901 (1/2) S751 OPEN/CLOSE DETECT OPEN CLOSE LEVEL SHIFT Q731 TABLE ADDRESS SENSOR IC731 + ROTARY ENCODER S711 7FIN LM-F 9RIN TM-R 4OUT1 2OUT2 M741 (TABLE) M TABLE MOTOR DRIVE IC712 7FIN TM-F LM-F, LM-R, TM-F, TM-R D S-MUTE, O-P

44、OWER, HOLD B 42 LCHO 45 RCHO R-CH CD-L A APC FIN2 FIN1 LDD LDS TIN2 TIN1 XOUT XIN RF 4 EFMIN 3 ERROR CORRECT EQ, AGC COMMAND INTERFACE CLOCK GENERATOR PH, BH RF AMP TBAL A/D CONVERTER D/A CONVERTER EXTERNAL AUDIO IN SERIAL OUT D/A CONVERTER SERVO PROCESSOR AUTOMATIC POWER CONTROL Q701 27I-POWER DOWN

45、 POWER DOWN RESET RESET, POWER DOWN C SIGNAL PATH : CD PLAY R-ch is omitted due to same as L-ch. (Page 24) (Page 24) (Page 24) (Page 23) R-CH DISC TRAY ADDRESS DETECT I/01 I/016 A0 A8 MDATA0 MDATA15 MADRS0 MADRS8 27 OE45OEB 13 WE42WEB 14 RAS41RASB 29 LCAS43CASLB 28 UCAS44CASUB IC802 MEMORY 2-5, 7-10

46、, 31-34, 36-39 23-30, 33-4060-53, 50 16-19, 22-26 MUTING Q311 MUTING CONTROL SWITCH Q312 CX-JT8 2323 10 CAPSTAN/REEL MOTOR DRIVE Q601 11 PLUNGER DRIVE (DECK-A) Q602 M M TAPE MECHANISM DECK BLOCK (CAPSTAN/REEL) (DECK-A) (DECK-B) LED DRIVER, TAPE MECHANISM CONTROLLER IC202 MOTOR 3DATA 4CLOCK 87 I-LC72

47、121 DI 92 O-LC72121/BU2099 CLK 9O-LC72121 CE 88 I-TUNER TUNE 97 I-TUNER STEREO 2I-BU1924 DI 3I-BU1924 CLK 21 I-MIC/I-TU SIG 19 I-SPEANA M 91 O-LC72121/M61529/BU2099 DO 5LCK 18 SO A-SOL G TAPE-L, REC-L (Page 24) K DI, SO, CLK, MCLK, LCK, (Page 24) J TUNER-L (Page 24) D LM-F, LM-R, TM-F, TM-R (Page 22

48、) TUNER UNIT AM LOOP FM ANT AM ANT L-CH R-CHR-CH TU-MUTE DI DI CLK CLK S-OUT LCK DI BIAS OSC L201 REC BIAS SWITCH Q228 +9V BIAS OSC Q223 ERASE HRPE1 (REC/PB/ERASE) (DECK-B) HP1 (PB) (DECK-A) L-CH R-CHR-CH R-CH L-CH R-CHR-CH 18 I-SPEANA L 20 I-SPEANA H 76 I-HP MUTE BAND-PASS FILTER Q204 206 KEY ACTIV

49、E SWITCH Q504, 505 28 I-RMC REMOTE CONTROL RECEIVER IC802 S301 309, S311 331 (FRONT PANEL KEY) 83 I-VOL B 84 I-VOL A ROTARY ENCODER S801 SPEANA AMP Q201, 202 B+ SWITCH Q921 FL901 FLUORESCENT INDICATOR TUBE MUTING Q219, 221 12 PLUNGER DRIVE (DECK-B) Q603 B-SOL LED213 LED901 A-PHOTO B-SOL A-SOL CAPM+ B-PHOTO A-HALF B-HALF A-MODE B-MODE REC (FWD) REC (REW) 9I-BASS +3.3V B+ D603 610 I-B-PHOTO I-B-HALF I-REC (FWD) S10/I-REC (REW) S6 S10 S1 S5, S11 S26 G2 G11 48 52 49 53 50 55 S7/I-A-PHOTO 95O-KEYSCAN S8/I-A-HALF U8 U9 U7 S10/U11 S7/U5 S8/U6 S9/I-B-MODE 47