SERVICE MANUAL
No.21062
Jan. 2002
COPYRIGHT
2002 VICTOR COMPANY OF JAPAN, LTD.
Safety precautions
Important for laser products
Preventing static electricity
Disassembly method
1-2
1-3
1-4
1-5
Wiring connection
Adjustment method
Description of major ICs
1-12
1-13
1-15~33
Contents
DVD DIGITAL CINEMA SYSTEM
TH-A5
TH-A5
Area suffix
A ------------------ Australia
US -------------- Singapore
UB ------------- Hong Kong
UW -- Brazil,Mexico,Peru
UY --------------- Argentina
UJ ------------- U.S.Military
UG ------------------ Turkey,
South Africa,Egypt
SP-XCA5
SP-XSA5 2
XV-THA5
SP-WA5
DIGITAL
SURROUND
DIGITAL
COMPACT
DIGITAL VIDEO
STANDBY
AUDIO/FM MODE
DSP
VOLUME
SOURCE
DVD DIGITAL CINEMA SYSTEM TH-A5
STANDBY/ON
DISPLAY
TV/VIDEO
TOP MENU
AUDIO
ON
TUNER PRESET
ENTER
VCR CHANNEL
TUNING
DVD
FM/AM
AUX
MUTING
STANDBY/ON
VCR
VCR
CONTROL
MENU
TV
AUDIO/
FM MODE SUBTITLE
RETURN
STEP
OFF
TV VOLUME
TV CHANNEL
VOLUME
B.SEARCH
F.SEARCH
DOWN
UP
REW
FF
RM-STHA5U
DVD CINEMA SYSTEM
SP-XSA5 2
TH-A5
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 ground
Place 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.)
TH-A5
1-3
Important for laser products
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.
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.
REPRODUCTION AND POSITION OF LABELS
!
Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
CLASS 1
LASER PRODUCT
TH-A5
1-4
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. 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.
Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for pick-up and how to detach the substrate.
(caption)
Anti-static wrist strap
Conductive material
(conductive sheet) or iron plate
Solder is put up before the card
wire is removed from connector
on the pick up board as shown in
Figure.
(When the wire is removed
without putting up solder, the CD
pick-up assembly might destroy.)
Please remove solder after
connecting the card wire with
when you install picking up
in the substrate.
1.
2.
DVD loading
mechanism
DVD loader board
Pick up board
Card wire
Short land
Connector
DVD mechanism assembly (bottom side)
(These two points are
soldered respectively,
and are made to
short-circuit)
TH-A5
1-5
Remove the four screws A attaching the top cover
on the both sides of the body.
Remove the two screws B on the back of the body.
Remove the top cover from behind in the direction of
the arrow while pulling both sides outward.
1.
2.
3.
Disassembly method
Removing the top cover
(See Fig.1)
Prior to performing the following procedure, remove
the top cover.
Remove the one screw a and remove the earth wier.
Remove the three screws C attaching the front panel
assembly on the bottom of the body.
Remove the two screws D attaching the front panel
assembly on the both sides of the body.
Remove the claw1, claw2 and claw3, and detach the
front panel assembly toward the front.
Disconnect the card wire from the connector DW20
on the DSP board.
1.
2.
3.
4.
5.
Removing the front panel assembly
(See Fig.2A, 2B and 3)
Prior to performing the following procedure, remove
the top cover.
Disconnect the power cord from the connector CW1
on the main board and pull up the cord stopper
upward.
Notes : The power cord is exchangeable.
1.
Removing the power cord
(See Fig.4)
D
(both side)
Claw2 (both side)
Fig.1
Fig.2A
Fig.2B
Fig.3
Fig.4
A 2
B
Top cover
CC
Claw1
Power cord
stopper
Power cord
Tie band
Front panel assembly
(bottom side)
Front panel
assembly
Front panel assembly
(Inner side)
Rear panel
Claw3
DSP board
Display board
a
(fixing the earth wire)
DW20
CW1