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MX-K50R SERVICE MANUAL COMPACT COMPONENT SYSTEM MX-K50R Area suffix B ------------------------ U.K. E ---- Continental Europe EN ----- Northern Europe EV ------- Eastern Europe STAND BY DISC CHANGE STANDBY/ON CD-R/ RW PLAYBACK M X-K50R SOUND M ODE STAN DBY/ ON...
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MX-K50R 1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. Services should be performed by qualified personnel only.
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MX-K50R (U.K only) 1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer.
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MX-K50R Important for laser products 5.CAUTION : If safety switches malfunction, the laser is able 1.CLASS 1 LASER PRODUCT to function. 2.DANGER : Invisible laser radiation when open and inter 6.CAUTION : Use of controls, adjustments or performance of lock failed or defeated. Avoid direct exposure to beam.
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MX-K50R Preventing static electricity 1. Grounding to prevent damage by static electricity Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
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MX-K50R Metal cover Disassembly method Removing the metal cover (See Fig.1) Remove the three screws A attaching the metal cover on the back of the body. Remove the six screws B attaching the metal cover on both sides of the body.
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MX-K50R CW105 CD board CW107 Rear panel CD changer unit RCW6 Fig.6 Front panel assembly CD changer unit Main board Fig.5 (both sides) Rear panel Fig.7 Removing the front panel assembly FCW3 Main board Front panel JCW2 (See Fig.8 to 10)
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MX-K50R Joint2 (Bottom side) Removing the heat sink & amp. board (See Fig.8, 11 and 12) Prior to performing the following procedure, remove the metal cover and the CD changer unit. Fig.10 Disconnect the card wire from the connector ACW1...
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MX-K50R Removing the main board (See Fig. 14) FCW3 JCW2 Prior to performing the following procedure, remove JCW1 the metal cover, CD changer unit and rear panel. Main board Disconnect the card wire from the connector FCW3 HCW3 Fuse board and the harness from the connector JCW1, JCW2 and HCW3 on the main board.
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MX-K50R Front panel assembly (inner side) <Front panel assembly> CD switch board Prior to performing the following procedure, remove the metal cover, the CD changer unit and the front panel assembly. UCW1 Removing the CD switch board Front board (See Fig.1)
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MX-K50R CD changer uint (reverse side) <CD changer unit> Prior to performing the following procedure, remove CD tray the CD changer unit. Removing the CD tray (See Fig.1 and 2) CD board Loading pulley Turn the black loading pulley gear on the under side...
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MX-K50R Removing the sensor board (See Fig.5) CD tray (reverse side) Prior to performing the following procedure, remove the CD tray. Remove the screw A attaching the sensor board on the CD tray. Remove the sensor board releasing the two tabs a.
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MX-K50R Removing the belt, the CD board and the switch board (See Fig.8 and 9) Belt Prior to performing the following procedure, remove the CD tray. Detach the belt from the pulley on the upper side of the CD changer unit (Do not stain the belt with grease).
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MX-K50R Removing the CD mechanism holder assembly (mechanism included) Motor connecter (See Fig.10 to 13) Disconnect the harness from connector on the CD mechanism board in the CD mechanism assembly on the under side of the CD changer unit. Disconnect the card wire from the pickup unit connector.
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MX-K50R <CD mechanism section> Shutter Shaft Pickup unit Removing the CD mechanism holder from the CD • chager unit. (Refer to "Removing the CD mechanism holder assembly" ) Removing the pickup unit See Fig.1) 1. Removing the cut washer on the feed gear sleeve and pull out the feed gear.
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MX-K50R R/P Head <Cassette mechanism section> Removing the record/playback mechanism. Removing the R/P head. 1. Remove the screw A on the right side of the R/P head.(Fig.1, Fig.2) 2. Remove the screw B on the left side of the R/P head.(Fig.1, Fig.2) Remove the erase head.
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MX-K50R Motor Mecha. terminal board Removing the motor. 1. Remove the two screws D fixing the motor. Be careful to grease's splash when the drive belt comes off.(Fig.5, Fig.6) 2. Unsolder the motor terminal.(Fig.5) Removing the mechanism board. Unsolder the four parts a on the solenoid...
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MX-K50R Wiring connection Color codes are shown below. Brown Orange Yellow Green Blue Violet Gray White Black 1-18...
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MX-K50R Adjustment method 1. Tuner * Adjustment Location of Tuner PCB LW OSC LW RF AM(MW) RF AM(MW) OSC Adjustment Adjustment ITEAM Adjustment Adjustment Received FREQ. 594 KHz 144~288 KHz 150 KHz 522~1629 KHz Adjustment point Maximum Maximum 2~7.0V 1~7.0V Output Output(Fig.1)
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MX-K50R FM THD Adjustment SSG FREQ. 98 MHz Adjustment Output Antenna point FM DETECTOR COIL Terminal (FM DET) Oscilloscope FM S.S.G Input 60 dB Output Speaker Minumum Distortion (0.4% below) Terminal Input output (Fig.2) Distortion Meter Fig.2 IF CENTER and THD Adjustment FM Search Level Adjustment SSG FREQ.
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MX-K50R 2. Cassette Deck To adjust tape speed Notes Cassette Deck Frequency Counter 1) Measuring tape: i) VT-712/MTT-111(or equivalent) (Tapes recorded with 3kHz) SPK OUT ii) AC-225/MTT-5512(or equivalent) output Fig.1 2) Connect the cassette deck to the frequency counter as in fig.1.
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MX-K50R 2. Adjust Deck 2 Play Level/REC BIAS Pre-Setup Step Item Pre-Setup To Adjust Standard Remark Condition After putting VT-703 AZIMUTH SPK OUT Turn the control Max output After into Deck 2 (VTVM is screw to as and same phase...
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MX-K50R Flow of functional operation until TOC read Check Point Play Key Power ON RESET a CD LSI Confirm that the voltage at the pin17 of KB9226(IC101) is "L" "H". Confirm that the voltage at the pin33 LIMIT SW ON of KB9226(IC101) is "H"...
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MX-K50R Maintenance of laser pickup (1) Cleaning the pick up lens (2) Life of the laser diode Before you replace the pick up, please try to When the life of the laser diode has expired, clean the lens with a alcohol soaked cotton the following symptoms will appear.
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MX-K50R Troubleshooting 1. Amplifier Power malfunction No output ,5,6,7 5,6,7 1-25...
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MX-K50R Description of major ICs 5L9290 (IC201) : Digital signal processor for CDP 1. Pin layout VSSA_PLL BCKO VCO1LF LRCKO VSSD_PLL SADTO VDDD_PLL DATX VDDD1_5V C2PO S5L9290X JITB DSP+DAC XOUT SBCK 48-LQFP-0707 VSSD1_5V VDDD3-5V EFMI VSSD2-3V LOCK VDDD2-3V SMEF MUTE...
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MX-K50R 3. Pin function Symbol Function VSSA_PLL Analog Ground for DPLL VCO1LF Pump out for VCO1 VSSD_PLL Digital Ground Separated Bulk Bias for DPLL VDDD_PLL Digital Power Separated Bulk Bias for DPLL (3V Power) VDDD1-5V Digital Power (5V Power, I/O PAD) X'tal oscillator input (16.9344MHz)
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MX-K50R 3.Pin function (2/2) Symbol Pin No. Type Functions Circut confguration Used as the synchronization clock when serial data is input Clock to the LC72131 (DI ), or when serial data is output (DO). Inputs serial data sent from the controller to the LC72131M.
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MX-K50R 3. Pin function Pin No. Symbol Function P16/BUZ Buzzer output P17/PWM0 Timer 1 output (PWM0 output) 8bit input/output port Input/output in bit unit 15V withstand at N-channel open drain output P70/INT0 INT0 input /HOLD release/N-channel Tr. ouptput forwatchdog timer...
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MX-K50R L4959 (RIC1) : Voltage regulator 1.Pin layout OUT 12V(a) OUT 8.6V EN 8.6V EN 12V(a) EN 12V(b) N.C. OUT 5.6V OUT 12V(b) TAB CONNECTED TO PIN 6 D97AU716A 2.Block diagram 2/10 5.6V, 250mA OUT 5.6V REGULATOR 8.6V, 600mA OUT 8.6V...
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MX-K50R KA9258D (IC301) : 4-ch Motor driver 1.Block diagram 28 27 26 25 24 23 22 21 20 19 18 17 16 15 REGULATOR T • S • D MUTE 10 11 12 13 14 LA1837 (IC01) : FM IF/DET AM RF/IF/DET 1.Block diagram...
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MX-K50R KA3082 (IC401, IC402) : DC motor driver 1.Pin layout 2.Pin function Pin No. Function Symbol DRIVER OUT Ground Output 1 Phase compensation PRE DRIVER VCTL Motor speed control VIN1 Input 1 VIN2 Input 2 LOGIC SWITCH SVCC Supply voltage (Signal)
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MX-K50R Block diagram CON 01 AUX IN UIC1 HIC1 MICOM TUNER FIC4 AUDIO FIC1 OIC1 DIGITAL SOURCE OPTICAL SELECTOR JIC1 TAPE P & E.VOL TAPE IC TAPE R DATX AUDIO AIC1 STK402-040 TAPE P/R TAPE P IC201 RCW5 IC101 RF AMP. &...
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MX-K50R MX-K50R Standard schematic diagrams To ACW1 Sheet 3/5 (2, B) Main section FCW2 To UCW6 Sheet 2/5 (5, A) To CW107 Sheet 4/5 (4, G) To CON01 Sheet 5/5 (2, B) To ACW2 Sheet 3/5 (5, B) To CW106...
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MX-K50R FL display & System control section To CW105 To UCW7 Sheet 4/5 (1, E) To RCW5 Sheet 1/5 (1, G) To FCW3 Sheet 1/5 (5, A) To UCW5 To UCW2 To UCW1 SHEET 2/5...
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MX-K50R MX-K50R Amp. section To RW2 Sheet 1/5 (3, G) To FCW2 Sheet 1/5 (5, G) Parts are safety assurance parts. When replacing those parts, make MAIN signal sure to use the specified parts. SHEET 3/5...
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MX-K50R CD section To RCW6 SHEET 1/5 (3, A) To OCW SHEET 1/5 (4, H) CD signal SHEET 2/5 (5, D) Sensor board Switch board SHEET 4/5...
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MX-K50R MX-K50R Tuner section AM LOOP FM TUNER (KST-F404VA-7 4GANG) FM ANT 3142 X-TAL 4.332MHz 4.7uF/35 60LMO SVC348 A114EK IC01 LA1837 IC03 BU1924 00007A 00011A DTC143TK DTC143TK DTC143TK 5.6K AM IF A33S 75E-380 FILTER LTSD450B RDS GND ICO2 LC72131M X-TAL 7.2MHz(12p/US)
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MX-K50R Printed circuit boards Main board Main board Headphone jack board Trans. board Fuse board...
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MX-K50R MX-K50R Front board CD switch board Front board Front key board...
MX-K50R PARTS LIST [ MX-K50R ] * All printed circuit boards and its assemblies are not available as service parts. Area suffix B ------------------------------- U.K. E ----------- Continental Europe EN ------------ Northern Europe EV -------------- Eastern Europe - Contents - 3- 3 Exploded view of general assembly and parts list (Block No.M1)
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MX-K50R Exploded view of general assembly and parts list Block No. Tuner board only EUROPE CD changer unit CD swith board Hphone jack board Front board Front key board Trans. board 23 x2 RFS2 22 x2 RFS5 RFS7 RFS6 RFS8...
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MX-K50R MX-K50R Parts list (General assembly) Parts list (General assembly) Block No. M1MM Block No. M1MM Item Parts number Parts name Q'ty Description Area Item Parts number Parts name Q'ty Description Area 6002-000126 SCREW 2 FH M3X10 BLK AH39-00258Q POWER CORD...
MX-K50R Cassette mechanism assembly and parts list Block No. ADR248DSW Note: Parts listed on the Parts List below can be supplied. However, parts that are not listed below cannot be supplied individually but only by purchasing the whole Cassette Mechanism Assembly Unit. (When ordering, use the Parts No.
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MX-K50R Electrical parts list (Main board) Block No. 01 Item Parts number Parts name Remarks Area Item Parts number Parts name Remarks Area 3722-000379 PIN JACK 4P/2C 3.5MM FR26 2001-000850 CARBON RESISTOR 560K 5% 1/8W FCW1 3708-001223 CONNECTOR 13P 1.25MM...
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MX-K50R Electrical parts list (Main board) Block No. 01 Item Parts number Parts name Remarks Area Item Parts number Parts name Remarks Area JC1L 2301-000361 M.CAPACITOR 1.2NF 10% 50V JR29 2001-000786 CARBON RESISTOR 47K 5% 1/8W JC1R 2301-000361 M.CAPACITOR 1.2NF 10% 50V...
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MX-K50R Electrical parts list (Main board) Block No. 01 Item Remarks Parts number Parts name Area 0402-000127 DIODE 1N4002 100V 1A RD10 0402-000127 DIODE 1N4002 100V 1A 0402-000127 DIODE 1N4002 100V 1A 0402-000127 DIODE 1N4002 100V 1A RD30 0402-000151 DIODE 1N5392 100V 1.5A...
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MX-K50R Electrical parts list (Front board) Block No. 02 Item Parts number Parts name Remarks Area Item Parts number Parts name Remarks Area ECW1 AH39-00249B LEAD CONNECTOR UQ11 0501-000610 TRANSISTOR KSA928A-Y 1W MR16 2001-000855 CARBON RESISTOR 560 5% 1/4W UQ12...
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MX-K50R Electrical parts list (Front board) Block No. 02 Item Parts number Parts name Remarks Area Item Parts number Parts name Remarks Area UR206 2001-000290 CARBON RESISTOR 10K 5% 1/8W UR79 2001-000290 CARBON RESISTOR 10K 5% 1/8W UR207 2001-000290 CARBON RESISTOR...
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MX-K50R Electrical parts list (Amp board) Block No. 03 Item Parts number Parts name Remarks Area Item Parts number Parts name Remarks Area ACE1 2201-000381 C.CAPACITOR 22NF 50V AR307 2001-000864 CARBON RESISTOR 56K 5% 1/8W ACE2 2201-000381 C.CAPACITOR 22NF 50V...
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MX-K50R Block No. 04 Electrical parts list (ECO board) Item Remarks Parts number Parts name Area ERL3 AH27-10001F CHOKE COIL 27UH ERL4 AH27-10001F CHOKE COIL 27UH AH26-80144W POWER TRANS 220V 50HZ 3711-000190 CONNECTOR 2P 7.92MM AH37-22001N CONNECTOR RCW5 3711-000967 CONNECTOR...
MX-K50R Electrical parts list (CD board) Block No. 05 Item Parts number Parts name Remarks Area Item Parts number Parts name Remarks Area CW101 3708-001252 CONNECTOR 16P 1MM C403 2203-000178 CHIP CAPACITOR 100NF 25V 1608 CW102 AH39-20561P LEAD CONNECTOR 6P 150MM...
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MX-K50R Block No. 05 Electrical parts list (CD board) Item Parts number Parts name Remarks Area R204 2007-000078 CHIP RESISTOR 1K 1/16W 1608 R205 2007-000078 CHIP RESISTOR 1K 1/16W 1608 R206 2007-000078 CHIP RESISTOR 1K 1/16W 1608 R207 2007-000078 CHIP RESISTOR...
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MX-K50R VICTOR COMPANY OF JAPAN, LIMITED AUDIO & COMMUNICATION BUSINESS DIVISION PERSONAL & MOBILE NETWORK BUSINESS UNIT. 10-1,1chome,Ohwatari-machi,Maebashi-city,371-8543,Japan (No.21122) 200208...