Jvc MXG 500 UW Service Manual
This is the 79 pages manual for Jvc MXG 500 UW Service Manual.
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Extracted text from Jvc MXG 500 UW Service Manual (Ocr-read)
Page 1
MX-G500 1-2 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. 2. Alterations of the design or circuitry of the product should not be made. Any design alterations of the product should not be made. Any design alterations or additions will void the manufacturer`s warranty and will further relieve the manufacture of responsibility for personal injury or property damage resulting therefrom. 3. Many electrical and mechanical parts in the products have special safety-related characteristics. These characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in the Parts List of Service Manual. Electrical components having such features are identified by shading on the schematics and by ( ) on the Parts List in the Service Manual. The use of a substitute replacement which does not have the same safety characteristics as the recommended replacement parts shown in the Parts List of Service Manual may create shock, fire, or other hazards. 4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the like to be separated from live parts, high temperature parts, moving parts and/or sharp edges for the prevention of electric shock and fire hazard. When service is required, the original lead routing and dress should be observed, and it should be confirmed that they have been returned to normal, after re-assembling. 5. Leakage currnet check (Electrical shock hazard testing) After re-assembling the product, always perform an isolation check on the exposed metal parts of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control shafts, etc.) to be sure the product is safe to operate without danger of electrical shock. Do not use a line isolation transformer during this check. Plug the AC line cord directly into the AC outlet. Using a "Leakage Current Tester", measure the leakage current from each exposed metal parts of the cabinet, particularly any exposed metal part having a return path to the chassis, to a known good earth ground. Any leakage current must not exceed 0.5mA AC (r.m.s.). Alternate check method Plug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms per volt or more sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by a 0.15 F AC-type capacitor between an exposed metal part and a known good earth ground. Measure the AC voltage across the resistor with the AC voltmeter. Move the resistor connection to each exposed metal part, particularly any exposed metal part having a return path to the chassis, and meausre the AC voltage across the resistor. Now, reverse the plug in the AC outlet and repeat each measurement. Voltage measured any must not exceed 0.75 V AC (r.m.s.). This corresponds to 0.5 mA AC (r.m.s.). 1. This equipment has been designed and manufactured to meet international safety standards. 2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained. 3. Repairs must be made in accordance with the relevant safety standards. 4. It is essential that safety critical components are replaced by approved parts. 5. If mains voltage selector is provided, check setting for local voltage. Good earth groundPlace this probe on each exposed metal part. AC VOLTMETER (Having 1000 ohms/volts, or more sensitivity) 1500 10W 0.15 F AC TYPE ! 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. In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the " " mark nearby are critical for safety. (This regulation does not correspond to J and C version.)
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1-3 MX-G500 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. 2. About the earth processing for the destruction prevention by static electricity In the equipment which uses optical pick-up (laser diode), optical pick-up is destroyed by the static electricity of the work environment. Be careful to use proper grounding in the area where repairs are being performed. 2-1 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. 2-2 Ground yourself Use an anti-static wrist strap to release any static electricity built up in your body. 3. Handling the optical pickup 1. 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.) 2. 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. 4. 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. It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it Conductive material (conductive sheet) or iron plate (caption) Anti-static wrist strap Attention when CD mechanism assembly is decomposed 1. Remove the CD changer unit. 2. Remove the CD changer mechanism. 3. Solder is put up before the card wire is removed from the pickup unit connector on the CD mechanism assembly. (When the card wire is removed without putting up solder, the CD pick-up assembly might destroy.) 4. Please remove solder after connecting the card wire with the pickup unit connector when you install picking up in the substrate. *Please refer to "Disassembly method" in the text for pick-up and how to detach the CD mechanism assembly. SolderingFig.1 Fig.2 Card wire Card wire Picup unit connector Picup unit connector CD changer unit CD changer mechanism
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MX-G500 1-38 HA12237 (JIC1) : Audio signal processor 1. Block diagram REC OUT(L) NC ALC(L) TEST (Open for normal use) IREF ALC ON/OFF High/Normal A (REC RETURN ON/OFF) Vcc MUTE ON/OFF REC MUTE OFF/ON GND ALCDET A/ B MUTE 120/60 (Norm/High) REC OUT(R) NC NC TAI(R) EQOUT(R) PB-EQ(R) ALC(R) REC IN(R) 14 56 89 10 AB 7 3 2 Return SW + EQALC PB OUT(R) PB-NF2(R) 34 35 36 37 38 39 40 GNDREC ReturnIN(L) AIN(R)IN(R) PB-NF1(R) Return SW NC30 31 32 33 RIP AB 28 120/60 (Norm/High) AIN(L) PB-NF1(L) 29 + TAI(L) EQOUT(L) PB-NF2(L)PB-EQ(L) 21 22 23 24 25 26 27 MUTE EQ NC PB OUT(L)REC IN(L) 11 1213 141516 17 181920 2. Pin function Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Symbol PB-NF2(R) PB-EQ(R) EQOUT(R) TAI(R) PBOUT(R) NC RECIN(R) NC RECOUT(R) ALC ON/OFF High/Norm A/B MUTE ON/OFF Function PB EQ feed back NAB output EQ output Tape input PB output NC pin REC-EQ input NC pin REC output Mode control input Mode control input Mode control input Mode control inputPin No. 15 16 17 18 19 20 21 22 23 24 25 26 Symbol REC MUTE OFF/ON Vcc GND IREF Test mode RECOUT(L) NC RECIN(L) NC PBOUT(L) Function Mode control input Vcc pin GND pin Equalizer reference current input Test mode pin REC output NC pin REC-EQ input NC pin PB outputPin No. 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Symbol TAI(L) EQOUT(L) PB-EQ(L) PB-NF2(L) PB-NF(L) AIN(L) RIP BIN(L) REC-RETURN GND BIN(R) NC AIN(R) PB-NF1(R) Function Tape input EQ output NAB output PB EQ feed back PB EQ feed back PB A deck input Ripple filter PB B deck input REC Return GND pin PB B deck input NC pin PB A deck input PB EQ feed back
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1-39 MX-G500 D0 D1 CLK CS Vcc S GND D24 D23 D22 D21 D20 D19 D18 D17 GND M66010 (UIC2) : I/O control 1.Pin layout 2.Block diagram 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1632 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 DO DI CLK CS S D24 D23 D22 D21 D20 D19 D18 D17D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 D16 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 D16 1 2 3 4 5 6 7 8 9 10 16 32 31 30 CLOCK INPUT CLK SET INPUT S CHIP SELECT CS INPUT SERIAL DATA DI INPUT GND GNDVcc DO SERIAL DATA OUTPUT PARALLEL DATA I/OD1 D2 D3 D22 D23 D24 Control circuit Shift register 1 DO D24 D23 D22 D3 D2 D1 Q24 Q23 Q22 Q3 Q2 Q1 D24 D23 D22 D3 D2 D1 Q24 Q23 Q22 Q3 Q2 Q1 DI Parallel output latch Shift register 2 STK402-040 (AIC1) / STK402-090 (AIC2) : Power amp. 1.Pin layout 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ch.1ch.2 + _+ _ CH1 INCH1 NFNC Pre VccBIAS CH1 VECH1 -VEVcc -Vcc CH2 +VECH2 -VEPre -VcoSUB GNDCH2 NFCH2 IN STK402-090 STK402-090 1 15
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H AB C DE FG 12 3 45 2-8 MX-G500 MX-G500 CD switch board Front board Front key board Mic board Front board