JVC-MXK7-cs-sm维修电路原理图.pdf

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1、SERVICE MANUAL COMPACT COMPONENT SYSTEM No.20958 May. 2001 COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD. MX-K7 MX-K7 Contents Safety precautions Important for laser products Preventing static electricity Disassembly method Adjustment method Flow of functional operation until TOC read Maintenance of l

2、aser pickup Replacement of laser pickup Description of major ICs 1-2 1-3 1-4 1-5 1-18 1-20 1-21 1-21 1-22 Area Suffix JU.S.A. RecordableReWritable ACTIVE BASS EX. COMPACT COMPONENT SYSTEM MX-K7 STANDBY/ON STANDBY PHONES REPEATPROGRAMRANDOM/STOPREC STARTDUBBING REC STARTCD CLOCK /TIMER TAPE A/B DISC

3、SKIP EJECT PLAYAREC/PLAYB CD CONTROL CD 1 AUX FM/AM CD TAPE CD 2 CD 3 CD-R/RW PLAYBACK VCD NUMBERRETURNPBC MAXMIN MICMIC VOL CANCELSET 1 BIT DUAL D/A CONVERTER PRESET TUNNIG / DEMO COMPU PLAY CONTROL ACTIVE BASS EXTENSION FULL - LOGIC CONTROLCD SYNCHRO RECORDING EJECT R O C K C L A S S I C P O P V O

4、 L U M E 3-CD PLAY TW2111A, Reverse ; TW2121A Fast Forward and Rewind ; TW2231A 9. Test disc : CTS-1000(12cm),GRG-1211(8cm) 10. Jitter meter Measurement conditions Power supply voltage AC120V (60Hz) Measurement output terminal : Speaker out : TP101(Measuring for TUNER/DECK/CD) : Dummy load 6ohm Radi

5、o input signal AM modulation frequency : 400Hz Modulation factor : 30% FM modulation frequency : 400Hz Frequency displacement : 22.5kHz Frequency Range AM531kHz1710kHz FM87.5MHz108MHz Standard measurement positions of volume and switch Power : Standby (Light STANDBY Indicator) S,A,BASS : OFF Sound m

6、ode : OFF Main VOL. : 0 Minimum Travers mecha set position : Disc 1 Mic MIX VOL : MAX ECHO : OFF Precautions for measurement 1. Apply 30pF and 33kohm to the IF sweeper output side and 0.082 F and 100kohm in series to the sweeper input side. 2. The IF sweeper output level should be made as low as pos

7、sible within the adjustable range. 3. Since the IF sweeper is a fixed device, there is no need to adjust this sweeper. 4. Since a ceramic oscillator is used, there is no need to perform any MPX adjustment. 5. Since a fixed coil is used, there is no need to adjust the FM tracking. 6. The input and ou

8、tput earth systems are separated. In case of simultaneously measuring the voltage in both of the input and output systems with an electronic voltmeter for two channels, therefore, the earth should be connected particularly. 7. In the case of BTL connection amplifier, the minus terminal of speaker is

9、 not for earthing. Therefore, be sure not to connect any other earth terminal to this terminal. This system is of an OTL system. MX-K7 1-19 Arrangement of adjusting positions Items Measurement conditions Measurement method Standard values Adjusting positions Tape recorder section Tuner section Casse

10、tte deck mechanism (Front side) Head azimuth screw (Forward side) PB Head (Deck-A) REC/PB Head (Deck-B) T1 L2 Main P.C.B. Assy CN308 L301 8-Pin Head screwHead screw Head azimuth screw (Forward side) 1.Playback the test tape VT703 (10KHz) or equivalent. 2.Adjust the head azimuth screw to obtain maxim

11、um output and both output of L / R is in 3dB. 3.Put on the screw lock paint after alignments. 1.Insert the recording tape in deck-B. 2.Starting the recording. 3.Adjust the oscillation frequency to 80KHz+/-3KHz by core of Oscillation coil of L301. Test tape : VT703 (10kHz) Measurement output terminal

12、 : Left and Right speaker output (6-ohm loaded) or Headphone Output (32-ohm loaded) Test tape : TYPE AC-514 Measurement output terminal : Erase head terminal (CN308 8-Pin) Maximum output 80kHz+/-3kHz Head azimuth screw Adjust the head azimuth screw only when the head has been changed. Bias coil: L30

13、1 Use the High- Impedance Probe for Frequency counter input. Cassette Head Azimuth Alignments Recording Bias Frequency Alignment Items Measurement conditions Measurement method Standard values Adjusting positions OSC coil adjustment 1.Set the Signal Generator signal to 530KHz the feed to Loop Antenn

14、a. 2.Receiving the signal and the adjust the OSC coil (L2) obtain the V.T is 1.40V +/-0.05V. Antenna coil check or adjustment 1.Change the receiving frequency to 600KHz. 2.Adjust the Antenna coil ( L2 ) obtain maximum sensitivity. (Adjust the SSG output to out of AGC range.) 1.Set the receiving freq

15、uency to 530KHz. 2.Feed the 450KHz signal to AM IF input. 3.Adjust the IFT Block T1 obtain to maximum output. (Adjust the SSG output to out of AGC range.) Input signal : 530kHz Measurement point : Resistor R3 (AM) Resistor R6 (FM) Input signal : 600kHz Input signal : 530kHz V.T : 1.40V+/-0.05V Maxim

16、um sensitivity Maximum output OSC/Antenna coil : L2 Adjust the OSC coil only when the AM coil block has been changed. IFT (T1) Adjust the IFT only when the IFT block has been changed. AM Tracking Alignments AM IFT Alignments Note: The adjustment of CD section is not required. FM VT voltage measureme

17、nt point R3 R6 AM VT voltage measurement point Antenna coil OSC coil MX-K7 1-20 Flow of functional operation until TOC read Slider turns REST SW ON. Automatic tuning of TE offset Laser ON Detection of disc Automatic measurement of Focus S-curve amplitude Automatic tuning of Focus offset Disc is rota

18、ted Focus servo ON (Tracking servo ON) Automatic tuning of Tracking error balance Automatic measurement of Tracking error amplitude Automatic tuning of Focus error balance Disc to be braked to stop Tracking servo on states Tracking servo off states Disc states to rotate TOC reading finishes Automati

19、c measurement of TE amplitude and automatic tuning of TE balance 500mv/div 2ms/divFig.1 Approx.3sec pin 20 of IC611(TE) Approx 1.8V VREF Tracking error waveform at TOC reading Power ON Play Key Confirm that the Focus error S-cuve signal at the pin32 of IC601 is approx.2Vp-p Confirm that the signal f

20、rom pin24 IC601 is 0V as a accelerated pulse during approx.400ms. Confirm the waveform of the Tracking error signal. at the pin 20 of IC611 (R643) (See fig-1) Automatic tuning of Focus error gain Automatic tuning of Tracking error gain TOC reading Play a disc Confirm the eys-pattern at the lead of T

21、P3 Confirm that the voltage at the pin5 of CN602 is HLH. Check Point Check that the voltage at the pin40 of IC601 is + 5V? MX-K7 1-21 Turn off the power switch and,disconnect the power cord from the AC OUTLET. Replace the pickup with a normal one.(Refer to Pickup Removal on the previous page) Plug t

22、he power cord in,and turn the power on. At this time,check that the laser emits for about 3seconds and the objective lens moves up and down. Note: Do not observe the laser beam directly. Play a disc. Check the eye-pattern at TP3. Finish. Maintenance of laser pickup (1) Cleaning the pick up lens Befo

23、re you replace the pick up, please try to clean the lens with a alcohol soaked cotton swab. (2) Life of the laser diode When the life of the laser diode has expired, the following symptoms will appear. 1. The level of RF output (EFM output:ampli tude of eye pattern) will below. Is the level of RFOUT

24、 under 1.25V 0.22Vp-p? Replace it. NO YES O.K (3) Semi-fixed resistor on the APC PC board The semi-fixed resistor on the APC printed circuit board which is attached to the pickup is used to adjust the laser power.Since this adjustment should be performed to match the characteristics of the whole opt

25、ical block, do not touch the semi-fixed resistor. If the laser power is lower than the specified value,the laser diode is almost worn out, and the laser pickup should be replaced. If the semi-fixed resistor would be adjusted when the pickup operates normally,the laser pickup may be damaged due to ex

26、cessive current. Replacement of laser pickup MX-K7 1-22 AN22000A (IC611) : CD-DA Head Amp. 1. Terminal layout 3. Block diagram 2. Pin function Description of major ICs 132 1617 RF_EQ NRFDET AMP AGC 6 24 7548 BDO SUBT 1112 OFTR 3TENV VDET 1314 9 10 15 32 31 22 23 GCABCA AMP 30 29 GCABCA + - AMP SUBT

27、27 28 21 20 19 18 GCABCA AMP 17 GCABCA + - 2 1 + - - + RFOUT RFIN GCTL 26 TBAL 25163 FBAL LD PD Pin No. Function Symbol I/O Pin No. Function Symbol I/O 1PDIAPC Amp. input terminal 2LDOAPC Amp. output terminal 3VCC-Power supply terminal 4RFNIRF adder Amp. inverting input terminal 5RFOUTORF adder Amp.

28、 output terminal 6RFINIAGC input terminal 7CAGCIInput terminal for AGC loop filter capacitor 8ARFOAGC output terminal 9CBAICapacitor connecting terminal for HPF-Amp. 103TOUTO3 TENV output terminal 11CBOOICapacitor connecting terminal for envelope detection on the darkness side 12BDOOBDO output termi

29、nal 13COFTRICapacitor connecting terminal for envelope detection on the light side 14OFTROOFTR output terminal 15NRFDETONRFDET output terminal 16GND-Ground 17VREFOVREF output terminal 18VDETOVDET output terminal 19TEBPFIVDET output terminal 20TEOUTOTE Amp. output terminal 21TENITE Amp. inverting inp

30、ut terminal 22FENIFE Amp. inverting input terminal 23FEOUTOFE Amp. output terminal 24GCTLOGCTL & APC terminal 25FBALOFBAL control terminal 26TBALOTBAL control terminal 27EITracking signal input terminal 1 28FITracking signal input terminal 2 29DIFocus signal input terminal 4 30BIFocus signal input t

31、erminal 3 31CIFocus signal input terminal 2 32AIFocus signal input terminal 1 MX-K7 1-23 BA15218 (IC102) : Dual low noise operational amp. 1. Terminal layout Pin No.Symbol Function I/O Pin No.Symbol Function I/O 2. Pin function BA5936S (IC621) : 6 channel BTL driver 1. Block diagram -+ +- OUT1 - IN1

32、 +IN1 VEE Vcc OUT2 - IN2 +IN2 32 12345678910111213141516 31 LEVEL SHIFT MUTE T.S.D 27262524232221 D x2 30 D x2 29 x3/8 28 x3/8 20 LEVEL SHIFT D 19 LEVEL SHIFT D 1817 DD BIAS BIAS Vcc100 13.3k +- BIAS 100 13.3k +- LEVEL SHIFT DETECTION OF REG-OUT CURRENT x2x2 x3/8x3/8 LEVEL SHIFT D LEVEL SHIFT DDDDD

33、BIAS VccVcc 100 13.3k -+ BIAS 100 13.3k 10k 10k -+- 1OUT1-OCH1 negative output 2OUT1+OCH1 positive output 3OUT2-OCH2 negative output 4OUT2+OCH2 positive output 5IN2ICH2 input 6IN1ICH1 input 7VCC-Power supply terminal 8VCC-Power supply terminal 9REG-IIRegulator current detection terminal 10REG-BOConn

34、ect to base terminal of external transistor 11REG-OUTOConstant voltage output (Connect to collector terminal of external transistor) 12IN3-RICH3 reverse input 13IN3-FICH3forward input 14OUT3+OCH3 positive output 15OUT3-OCH3 negative output 16GND-Ground 17OUT4-OCH4 negative output 18OUT4+OCH4 positiv

35、e output 19OUT5-OCH5 negative output 20OUT5+OCH5 positive output 21IN5ICH5 input 22IN4ICH4 input 23VCC-Power supply terminal 24BIAS INIBias input terminal 25GND-Ground 26GND-Ground 27MUTE INIMute input terminal 28IN6-RICH6 reverse input 29IN6-FICH6 forward input 30OUT6+OCH6 positive output 31OUT6-OC

36、H6 negative output 32GND-Ground MX-K7 1-24 Pin No.Symbol Function I/O Pin No.Symbol Function I/O 2. Pin function LA1823 (IC1) : 1chip AM/FM, MPX tuner system 1. Block diagram 1AM_RFINIAMRF signal input 2REG.- 3AM_OSC-AM local oscillation circuit 4VCC_1-Power supply terminal 5FM_MIXOUTOOutput termina

37、l for FM mixer 6GND_1-Ground 7IF_BUFFEROIF buffer output 8ST_INDOStereo indicator output 9AM_MIXOUTOOutput terminal for AM mixer 10FM_IF INIInput of FMIF signal 11AM_IF INIInput of AMIF signal 12AGCIAGC voltage input terminal 13FM_DETOFM detection signal output 14ST/MON_SWIStereo/Monaural switching

38、signal input 15AM/FM_SWIAM/FM switching signal input 16L_OUTOOutput L-channel 17R_OUTOOutput R-channel 18MPX_INIMultiplex signal input 19DET_OUTOAM/FM detection output 20FM_OSC-FM local oscillation circuit 21VCC_2-Power supply terminal 22FM_RFOUTOOutput of FMRF signal 23GND_2-Ground 24FM_RFINIInput

39、of FMRF signal 24 FM RF FM OSC 23 GND2 21 VCC2 20 FM MIX PHASE COMP 15 PILOT DET 14 FM DET 131918 MUTE 1716 DECODER 22 124510111267893 ST SW FM S-METER AM DET VCOFFFF TRIG STSD FF AGC FM IF AM IF AM RF REGVCC1GND1 AM MIX AM OSC OSC BUFFER IF BUFFER MX-K7 1-25 LC72136N (IC2) : PLL Frequency synthesiz

40、er 1.Terminal layout 1 2 3 4 5 6 7 8 9 10 11 22 21 20 19 18 17 16 15 14 13 12 XTI FM CE DI CLOCK DO VCOSTOP AM/FM LW MW SDIN XT GND LPFI LPFO PD VCC FMIN AMIN NC IFCNT IFIN Pin No. 1 2 3 4 5 6 7 8 9 10 11 Pin No. 12 13 14 15 16 17 18 19 20 21 22 Symbol XTI FM CE DI CLOCK DO VCOSTOP AM/FM NC NC SDIN

41、Symbol IFIN IFCNT NC AMIN FMIN VCC PD LPFO LPFI GND XT Function Xtal oscillator connect (75KHz) LOW:FM mode When data output/input for 4pin(input) and 6pin(output): H Input for receive the serial data from controller Sync signal input use Data output for Controller Output port Low: MW mode Open stat

42、e after the power on reset Input/output port Input/output port Data input/output Function IF counter signal input IF signal output Not use AM Local OSC signal output FM Local OSC signal input Power supply(VDD=4.5 5.5V) When power ON:Reset circuit move PLL charge pump output(H: Local OSC frequency He

43、ight than Reference frequency. L: Low Agreement: Height impedance) Output for active lowpassfilter of PLL Input for active lowpassfilter of PLL Connected to GND Xtal oscillator(75KHz) I/O I O I I I O O O - - I/O I/O I O - I I - O O I - I Reference Driver Phase Detector Charge Pump Unlock Detector Un

44、iversal Counter Swallow Counter 1/16,1/17 4bit 12bit Programmable DriverS Swallow Counter 1/16,1/17 4bit Data Shift Register & Latch Power on Reset C2B I/F 1/2 7821113 21 17 6 5 4 3 15 16 22 1 18 19 20 12 2. Block diagram 3. Pin function MX-K7 1-26 Pin No.Symbol Function I/O Pin No.Symbol Function I

45、/O 3. Pin function TA8189N (IC401) : REC/PB amp. 1. Terminal layout2. Block diagram 1CH1_AIInput for playback amp. (Ch1): A cassette (PB) 2CH1_BIInput for playback amp. (Ch1): B cassette (REC/PB) 3NF1INF terminal for playback amp. 4EQ1OMetal output for playback amp. 5PREOUT1OOutput terminal for play

46、back amp. 6MIX_OUTOMixing output 7GND1-Ground 8EQSWIMetal/Normal mode select switch 9REC_OUT1OOutput for recording amp. 10REC_NF1INF terminal for recording amp. 11REC_IN1IInput for recording amp. 12GND1-Ground terminal 13ALCIALC filter terminal 14REC_IN2IInput for recording amp. 15REC_NF2INF termina

47、l for recording amp. 16REC_OUT2OOutput for recording amp. 17CGOCharge detection terminal 18VCC-Power supply terminal 19A/B_SWIREC amp. Select switch (A cassette/B cassette) 20PREOUT2OOutput terminal for playback amp. 21EQ2OMetal output for playback amp. 22NF2INF terminal for playback amp. 23CH2_BIIn

48、put for playback amp. (Ch2): B cassette (REC/PB) 24CH2_AIInput for playback amp. (Ch2): A cassette (PB) 1 2 3 4 5 6 7 8 9 10 11 12 CH1_A CH1_B NF1 EQ1 PREOUT1 MIX_OUT GND1 EQSW REC_OUT1 REC_NF1 REC_IN1 GND 24 23 22 21 20 19 18 17 16 15 14 13 CH2_A CH2_B NF2 EQ2 PREOUT2 A/B_SW VCC CG REC_OUT2 REC_NF2

49、 REC_IN2 ALC 22 23CH2_B 24CH2_A 1CH1_A 2CH1_B 202119 A/B M/N ALC Vref1 18 Iref 17 Vref2 - + Ch2 + - Ch1 - + Ch2 + - Ch1 NF2 EQ2 PREOUT2 A/B_SW VCC CG 354678 NF1 EQ1 PREOUT1 MIX_OUT GND1 EQSW 16 REC_OUT2 15 14 REC_IN2 13 ALC 12 GND 11 REC_IN1 REC_NF2 9 REC_OUT1 10 REC_NF1 MX-K7 1-27 TC74HC4094AP (IC402) : 8-bit shift and store resister 1. Terminal layout 2. Block diagram