JVC XL-PM20SL Service Manual

SERVICE MANUAL

PORTABLE CD PLAYER

XL-PM20SL

Area suffix

C -------------------------- Canada E ----------- Continental Europe

XL-PM20SL

Contents

Safety precautions Preventing static electricity Important for laser products Disassembly method

1-2 1-4 1-5 1-6

Adjustment method Trouble shooting Description of major ICs

1-8 1-8 1-9 17

No.21133

Aug. 2002

XL-PM20SL

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.).

0.15 F AC TYPE

1500 10W

Good earth ground

AC VOLTMETER (Having 1000 ohms/volts, or more sensitivity)

Place this probe on each exposed metal part.

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.

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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XL-PM20SL

(U.K only)

2. Any unauthorised design alterations or additions will void the manufacturer's guarantee ; furthermore the manufacturer cannot accept responsibility for personal injury or property damage resulting therefrom.

3. Essential safety critical components are identified by ( ) on the Parts List and by shading on the schematics, and must never be replaced by parts other than those listed in the manual. Please note

however that many electrical and mechanical parts in the product have special safety related characteristics. These characteristics are often not evident from visual inspection. Parts other than specified by the manufacturer may not have the same safety characteristics as the recommended replacement parts shown in the Parts List of the Service Manual and may create shock, fire, or other hazards.

1. Service should be performed by qualified personnel only.

2. This equipment has been designed and manufactured to meet international safety standards.

3. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.

4. Repairs must be made in accordance with the relevant safety standards.

5. It is essential that safety critical components are replaced by approved parts.

6. If mains voltage selector is provided, check setting for local voltage.

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.

1-3

XL-PM20SL

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.

(caption) Anti-static wrist strap

Conductive material (conductive sheet) or iron plate

3. Handling the optical pickup

In order to maintain quality during transport and before installation, both sides of the laser diode on the

1. 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

2. source can easily destroy the laser diode.

4. Handling the traverse unit (optical pickup)

Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.

Remove solder of the short land 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.

Handle the flexible wire carefully as it may break when subjected to strong force.

It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.

5. Attention when traverse unit is decomposed

*Please refer to "Disassembly method".

Main board Flexible wire

Apply solder to the short land before the flexible wire is disconnected from the connector on the main board. (If the flexible wire is disconnected without applying solder, the CD pickup may be destroyed by static electricity.) In the assembly, be sure to remove solder from the short land after connecting the flexible wire.

1-4

Short land

Important for laser products

XL-PM20SL

1.CLASS 1 LASER PRODUCT

2.DANGER : Invisible laser radiation when open and inter

lock failed or defeated. Avoid direct exposure to beam.

3.CAUTION : There are no serviceable parts inside the Laser Unit. Do not disassemble the Laser Unit. Replace the complete Laser Unit if it malfunctions.

4.CAUTION : The compact disc player uses invisible laserradiation and is equipped with safety switches whichprevent emission of radiation when the drawer is open and the safety interlocks have failed or are de feated. It is dangerous to defeat the safety switches.

VARNING : Osynlig laserstrålning är denna del är öppnad

och spårren är urkopplad. Betrakta ej strålen.

VARO : Avattaessa ja suojalukitus ohitettaessa olet

alttiina näkymättömälle lasersäteilylle.Älä katso säteeseen.

5.CAUTION : If safety switches malfunction, the laser is able to function.

6.CAUTION : Use of controls, adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.

CAUTION

Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check.

ADVARSEL : Usynlig laserstråling ved åbning , når

sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling.

ADVARSEL : Usynlig laserstråling ved åpning,når

sikkerhetsbryteren er avslott. unngå utsettelse for stråling.

REPRODUCTION AND POSITION OF LABELS

CLASS 1

LASER PRODUCT

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XL-PM20SL

Disassembly method

Removing the bottom cabinet

(See Figs. 1 to 3.)

From the bottom side of the main body, remove the

1. six screws A from the bottom cabinet. (See Fig.1.)

Open the battery door, then remove the screw B

2. from the bottom cabinet. (See Fig.2.)

From the top side of the main body, pay attention to

3. remove the screw C from the middle cabinet before next procedure. (See Fig.3.)

Disengage the claws a of the bottom cabinet from

4. the middle cabinet and then remove the bottom cabinet.

Bottom cabinet

Battery door

Fig. 1

Bottom cabinet

Fig. 2

Removing the main parts

(See Figs. 4 to 10.)

Disconnect the flexible wire from connector CN7 on the main board. (See Fig.4.)

[Caution]

Remove the HOLD & HBS slide knobs.

Remove the HOLD & HBS board by releasing the screw D. (See Fig.5.)

Pay attention not damage the flexible wire during disconnection.

(See Fig.5.)

Claw a

HOLD slide knob

HBS slide knob

Claw a

Middle cabinet

Fig. 3

Flexible wire

CN7

Main board

Fig. 4

1-6

HOLD & HBS board

Fig. 5

+ 12 hidden pages