Jvc FSSD 78 V Service Manual

Page 1

FS-SD58V / FS-SD78V / FS-SD98V

JVB

SERVICE MANUAL

COMPACT COMPONENT SYSTEM

FS-SD58V
FS-SD78V/ FS-SD98V

Area Suffix
FS-S D58V
UB ......... Hong Kong
El
US .......... Singapore
CA-SDSBV sasossv

FS-SD78V / FS-S D98V

UF --------------- China
/ US ---------- Singapore
SP-SD78V, SDQSV CA-SD78V, CA-SDQBV SP»SD78V, SDQBV
COMPACT
@H§@ [flcnmpm CDMFACT
DIGITAL Aunlo U§@ Péathaclk n§@
VIDEO CD on 3 DIGITAL AUDIO
These models are different only speaker systems.
FS-SD78V and FS-SD98V are different only speaker cabinet.
contents These models not have adjustment.
Safety Precautions ----------------------- 1-2 Flow of functional operation
Important for laser products ............ 1-3 unit TOC read .................. 1.15
Preventing static electricity ------------- 1-4 Method of connecting
Dismantling and assembling treatment device wire -------- 1-17
the traverse unit --------------- 1-5 Description of major ICs ................. 1-18
Disassembly method -------------------- 1-6 ~14
Maintenance of laser pickup ----------- 1-15
Replacement of laser pickup ----------- 1-15
This service manual is printed on 100% recycled paper. No 20882

COPYRIGHT (97: 2000 VICTOR COMPANY OF JAPAN, LTD.
Nov. 2000

Page 2

FS-SD58V/FS-SD78V/FS-SD98V

-Safety Precautions

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 manufacturers
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.

0 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.)

0 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 1,5009 10W resistor paralleled by
a 0.15uF AC-type capacitor between an exposed

AC VOLTMETER
metal part and a known good earth ground. (Having 1000
Measure the AC voltage across the resistor with the ' 7 ohms/volts,
AC voltmeter. or more sensitivity)
Move the resistor connection to eachexposed metal ° °
part, particularly any exposed metal part having a 0.15MF AC TYPE
return path to the chassis, and meausre the AC _"_ Place this
voltage across the reSIstor. Now, reverse the plug In probe on
the AC outlet and repeat each measurement. voltage WV 5 each exposed
measured Any must not exceed 0.75V AC (r.m.s.). 15009 10W metal part.

This corresponds to 0.5 mA AC (r.m.s.).
Good earth ground

- Warning

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.

1-2

A CAUTION 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.

Page 6

FS-SD58V/FS-SD78V/FS-SD98V

Disassembly method

Page 20

FS-SD58V/FS-SD78V/FS-SD98V

I LA4905 (IC301) : 2ch BTL power IC
1. Pinlayput

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STBY 2% Standby 3w Switching a
regulator block 1
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H L S. l-I

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1
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Ripple
DC
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A B C D SW E
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->2< H-L-S-i 3w OUT1
Higher
Level signal 3w OUT2
selector
Amplifier output stage a SW GND
PRE GND (2)
Nonlinear/output stage

+ +OUT1
IN 1 G, +
- 44 o
BEEP _
amplifier

Power supply/ground shorting
BEEP 4\ protection circuit
Overvoltage/thermal protection
circuit

Input amplifier

CH 2 PWR GND 2
44» D @

IN 2 1) +
+ @ +OUT 2
Nonlinear amplifier/output stage
> ON MUTE _ Pop noise
ON TIME é?) muting circuit prevention circuit a N'C'

1-20