Jvc KDS 747 Service Manual
This is the 52 pages manual for Jvc KDS 747 Service Manual.
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Extracted text from Jvc KDS 747 Service Manual (Ocr-read)
Page 1
KD-S747 1-2 (No.49822) SECTION 1 Important Safety Precautions 1.1 Safety Precautions ! Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system. ! Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check.
Page 2
KD-S747 (No.49822)1-3 1.2 Preventing 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. 1.2.1 Grounding to prevent damage by static electricity Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players. Be careful to use proper grounding in the area where repairs are being performed. (1) Ground the workbench Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the traverse unit (optical pickup) on it. (2) Ground yourself Use an anti-static wrist strap to release any static electricity built up in your body. (3) Handling the optical pickup - In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.) - Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power source can easily destroy the laser diode. 1.3 Handling the traverse unit (optical pickup) (1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit. (2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a time when attaching it to the connector. (3) Handle the flexible cable carefully as it may break when subjected to strong force. (4) I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it. 1.4 Attention when traverse unit is decomposed *Please refer to "Disassembly method" in the text for the CD pickup unit. - Apply solder to the short land before the flexible wire is disconnected from the connector on the CD pickup unit. (If the flexible wire is disconnected without applying solder, the CDpickup may be destroyed by static electricity.) - In the assembly, be sure to remove solder from the short land after connecting the flexible wire. 1M (caption) Anti-static wrist strap Conductive material (conductive sheet) or iron plate PickupShort-circuit point (Soldering) Flexible wire Pickup Short-circuit point
Page 44
KD-S747 2-1 AB C D E F G 12 3 45 POSITION SET SWITCH LOAD&FEED MOTOR SPINDLE MOTOR SW1, SW2 PICK UP PSW SW1, SW2 CN501 IC561 CD DRIVER IC521 DSP & DAC IC501 RF AMP IC571 L.P.F. VF1,VF2, VT1,VT2, MD,LD DMO,FMO TRO,FOO CDON CD-RW BUS0~BUS3 BUCK,CCE RST SEL TEB RFGC TE,FE RFDC RFRP RFLO RO CD.L CD.R CJ601 S601~S618 KEY MATRIX JS690 ENCODER KEY0 KEY1 KEY2 ENC1 ENC2 IC601 LCD DRIVER LCD1 CN701 TU1 FM/AM TUNER IC701 CPU IC161 E.VOL FM/AM MONO SM SD/ST SEEK/STOP IC301 POWER AMP IC901 REGULATOR SPK BATTERY EACH BLOCK L-CH R-CH OUTLF OUTRF OUTLR OUTRR REAR L REAR R CD.L CD.R J301 LINE OUT LF+, LF- RF+, RF- LR+, LR- RR+, RR- COM1 COM2 COM3 S1 ~ S50 LCDCE LCDDA LCDCL VOLDA VOLCL RDSSCK RDSDA J1 ANT SW1,SW2,PSW LM,MSW CD-RW FEED+ FEED- SPINDLE+ SPINDLE- VF1,VF2, VT1,VT2, LD,MD, TRACKING+ TRACKING- FOCUS+ FOCUS-SPINDLE+ SPINDLE- FEED+ FEED- TRACKING+ TRACKING- FOCUS+ FOCUS- Block diagram CN901 IC71 RDS DETECTER