Jvc NXMD 1 R Service Manual
This is the 69 pages manual for Jvc NXMD 1 R Service Manual.
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Extracted text from Jvc NXMD 1 R Service Manual (Ocr-read)
Page 1
NX-MD1R/NX-MD1 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. When replacing them, be sure to use the parts of the same type and rating as specified by the manufacturer. (Except the J and C version)
Page 2
NX-MD1R/NX-MD1 1-3 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 Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as CD players. 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. Remove solder of the shorting round on the flexible wire 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 wire 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
Page 18
NX-MD1R/NX-MD1 1-19 Reference:The mechanism P.C. board can be removed without removal of the TRAMECHA assembly. Note: Before disconnecting the flexible wire coming from the pickup from the connector, be sure to solder its shorting round. If the flexible wire is connected without soldering, it may cause breakdown of the pickup. Removing the Mechanism P.C. Board (Refer to Fig 10.) 1. Solder the shorting round of the flexible wire connected with the mechanism P.C. board from the back of the mechanism assembly. 2. Disconnect the flexible wire from the connector CN601 on the mechanism P.C. board. 3. Remove the three screws C fastening the mechanism P.C. board. 4. Unsolder the two points of the part h and one point of the part i of the mechanism P.C. board. Then, remove the mechanism P.C. board upwards. Note: When reinstalling the mechanism P.C. board, connect the flexible wire coming from the pickup to the connector first and then remove the solder from the shorting round of the flexible cable. Fig. 10 C C C CN601 on mechanism P.C. board Flexible wire Shorting round Soldered part h Soldered part i
Page 57
NX-MD1R/NX-MD1 1-58 M63008FP (IC410) : 5ch Actuator driver 1.Terminal layout 2.Block diagram REG+ REGB IN1+ VBS1 Vm1 IN1- OUT1 VM1- VM1+ VM2+ VM2- OUT2 IN2- IN2+ MUTE1 MUTE2 SS,GND VREF VREFO GND CH3IN OUT3 IN3- VBS2 Vm2 IN3+ N.C VM3- VM3+ VM4+ VM4- VM5+ VM5- OUT5 IN5- IN5+ IN4+ IN4- OUT4GND 12 2021 161513 14 128 9 7 65 3439 38 40 37 41 42 34 35 31 30 23 24 22 29 28 26 25 27 19 17 18 10 1132 33 IN1+ IN1- OUT1 VM1(+) VM1(-) VM2(+) VM2(-) OUT2 IN2-I IN2+ VREFO VREF REGB REG+VREFE2 CH2 X5 CH1 X5 E1 VREG VBS1 VBS1VBS1 VBS2 VBS1 VBS1 VBS2 1.25V CH3 X8 CH4 X8 CH5 X8 E3 E4 E5 VBS2VBS2 VBS2 VBS2 Vm1 Vm2 R RR R Vrefm1Vrefm2 BIASHI :Sleep SLEEP TSD Low,Open MUTE ON 1~4 CH5CH VBS1 Vm1 VBS1 VBS2 Vm2 IN3- IN3+ OUT3 CH3 IN VM3(+) VM3(-) VM4(+) VM4(-) IN4- IN4+ OUT4 VM5(+) vm5(-) IN5- IN5+ OUT5 VREFO SS,GNDMUTE1 MUTE2 GND (4PIN)