JVC BC72 User manual

SERVICE MANUAL
COMPACT COMPONENET SYSTEM
No.21119
Jul. 2002
COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD.
VS-DT7R
VS-DT7R
COMPACTCOMPONENT SYSTEM
STANDBY/ON
PLAYMODE
REPEAT
FM MODE
TREBLEBASS
SET
CANCEL
SLEEPDIMMER
DISPLAYAHB PRO
DISPLAY
MODE
FM/AM
PTY
SEARCH
PTY
SELECT
TA/NEWS
/INFO
CLOCK
/TIMER OPEN/ CLOSE
VOLUME
MD/AUX
123
6
9
10
10
7
45
8
+
CA-VSDT7RSP-VSDT6 SP-VSDT6
Area suffix
E
EN
Continental Europe
Northern Europe

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TABLE OF CONTENTS
1 Important safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Warning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Caution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.4 Critical parts for safety. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.5 Preventing static electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.6 Handling the traverse unit (optical pickup) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.7 Attention when traverse unit is decomposed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.8 Important for laser products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Disassembly method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Main body section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Front panel assembly section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.3 CD mechanism assembly section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3 Adjustment method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.1 Flow of functional operation until TOC read . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2 Maintenance of laser pickup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.3 Replacement of laser pickup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4 Description of major ICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1 MN101CP30AKJ (IC701) : System control microcomputer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.2 KIA78S06P (IC702) : Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.3 MN662790RSC (IC651) : Digital servo & Digital signal prossesor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.4 UPC78L05J-T (IC191) : Three terminal voltage regulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.5 UPD780024AGKB62 (IC251) : Unit microcomputer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.6 LA4905 (IC301) : 2ch BTL power IC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.7 LB1641 (IC108) : DC motor driver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.8 MN101CP35DKB (IC811) : FL driver microcomputer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.9 BA15218F (IC102) : Dual operational amplifier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
4.10 AN22000A (IC601) : RF & Servo amplifier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.11 LA1838 (IC1) : FM AM IF amplifier & Detector, FM MPX Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.12 LA6575H (IC801) : Focus & Spindle & Feed & Tracking BTL driver . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.13 GP1FA550TZ (J3601) : Fiber optic transmitter/Receiver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.14 LC72136N (IC2) : PLL frequency synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.15 LC72723 (IC3) : RDS decoder. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.16 NJM4580D-D (IC101) : Dual operational amplifier. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.17 RPM6938-SV4 (IC801, IC802, IC812) : Remote control receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.18 LC75342M (IC501) : E. volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.19 XC62HR3502P (IC291) : Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

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SECTION 1
Important safety precautions
1.1 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 characteris-
tics 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 sub-
stitute 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 reassembling.
(5) Leakage shock hazard testing)
After reassembling 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, particu-
larly 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 sen-
sitivity in the following manner. Connect a 1,500 10W
resistor paralleled by a 0.15 F AC-type capacitor be-
tween 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 measure 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.).
1.2 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 lo-
cal voltage.
1.3 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 pre-
forming repair of this system.
1.4 Critical parts for safety
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 JC version)

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1.5 Preventing 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.
1.5.1 Grounding to prevent damage by static electricity
Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players.
Be careful to use proper grounding in the area where repairs are being performed.
(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) 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 op-
tical 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.
1.6 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)I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it
1.7 Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for the CD pickup unit.
• Apply solder to the short land before the flexible wire is dis-
connected from the connector on the CD pickup unit.
(If the flexible wire is disconnected without applying solder,
the CDpickup may be destroyed by static electricity.)
• In the assembly, be sure to remove solder from the short land
after connecting the flexible wire.

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1.8 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 laser
radiation and is equipped with safety switches which
prevent 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 LABEL and PRINT
WARNING LABEL
CAUTION
Please use enough caution not to see the beam directly or
touch it in case of anadjustment or operation check.
VARNING
Osynlig laserstrålning är denna del är öppnasd och spårren är
urkopplad. Betrakta ej strålen.
VARO
Avattaessa ja suojalulitus ohitettaessa olet alttiina näkymät-
tömälle lasersateilylle. Älä katso säteeseen.
ADVARSEL
Usynlig laserstrling ved åbning, når sikkerhedsafbrydere er ude
af funktion. Undgå udsasttelse for stråling.
ADVARSEL
Usynlig laserstråling ved åpning, når sikkerhetsbryteren er avs-
lott. unngå utsettelse for stråling.

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SECTION 2
Disassembly method
2.1 Main body section
2.1.1 Removing the top lens [VS-DT9R only]
(See Figs.2-1)
From the top side of the main body, remove the four screws A
attaching the top lens.
Fig.2-1
2.1.2 Removing the bottom panel
(See Figs. 2-2 and 2-3.)
• Remove the top lens. [VS-DT9R only]
(1) From the rear side of the main body, remove the three
screws Battaching the bottom panel.
(2) From the bottom side of the main body, remove the two
screws Cattaching the bottom panel.
(3) Remove the bottom panel in an upward direction.
Fig.2-2
Fig.2-3
2.1.3 Removing the top panel
(See Fig. 2-4.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
(1) Slide the top panel toward the rear (direction of the arrow)
and disengage it from the engagement sections aand bof
the bottom chassis.
(2) Remove the top panel in an upward direction.
Fig.2-4

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2.1.4 Removing the CD mechanism assembly
(See Fig. 2-5.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
(1) From the top side of the main body, disengage the claw c
of the CD mechanism assembly and then remove the push
button.
(2) Remove the six screws Dand screw Eattaching the CD
mechanism assembly.
(3) Disconnect the wire from connector CN802 on the LED
board.
(4) Remove the CD mechanism assembly in an upward direc-
tion.
Fig.2-5
2.1.5 Removing the front panel assembly
(See Figs. 2-6 and 2-7.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
(1) Remove the tie band bundling the wires of the front panel
assembly.
(2) Disconnect the wires from connectors CN106 and CN182
on the main board.
(3) Disconnect the card wires from connectors CN171 and
CN183 on the main board.
(4) Remove the wire holder holding the card wire of the front
panel assembly.
(5) From the front side of the main body, remove the two
screws Fattaching the front panel assembly.
(6) Disengage the claws dof the front panel assembly from
the bottom chassis and then remove the front panel as-
sembly in the direction of arrow.
[Reference]
•Before attaching the front panel assembly, pass the card
wire of the front panel assembly through the hole on the
bottom chassis.
•After attaching the front panel assembly, bundling the
card wire and wires of the front panel assembly using a
wire holder and tie band.
Fig.2-6
Fig.2-7

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2.1.6 Removing the tuner board
(See Figs. 2-8 and 2-9.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
(1) Disconnect the card wire from connector CN111 on the
main board.
(2) From the rear side of the main body, remove the two
screws Gattaching the FM/AM antenna terminals on the
tuner board.
(3) Take out the tuner board from the bottom chassis. 3.
Fig.2-8
2.1.7 Removing the speaker board
(See Figs. 2-8 and 2-9.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
(1) Remove the tie band bundling the wires on the speaker
board.
(2) Disconnect the wires from connectors CN101 and CN102
on the speaker board.
(3) From the rear side of the main body, remove the three
screws Hattaching the speaker/digital out terminals on the
speaker board.
(4) Take out the speaker board from the bottom chassis.
[Reference]
•After connecting the wires to the speaker board, bundle
them using a tie band.
•Insert the CD mechanism assembly wire into the notch on
the bottom chassis. (See Fig. 2-8.)
Fig.2-9

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2.1.8 Removing the main board
(See Figs. 2-10 and 2-11.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
• Remove the front panel assembly.
• Remove the tuner board.
• Remove the speaker board.
(1) Disconnect the wire from connector CN192 on the power
amplifier board.
(2) Disengage the wire clamp bundling the wire of the power
transformer.
(3) Disconnect the wires from connectors CN181, CN191 and
CN194 on the main board.
(4) Remove the screw J, which retains the main board, to-
gether with the wire holder.
(5) Remove the three screws K and screw K' attaching the
main board.
(6) Remove the two screws Lattaching the main board and
then remove the rear panel.
(7) Take out the main board from the bottom chassis.
[Reference]Attaching the main board
•When attaching the screw K', attach the earth wire of the
main board at the same time.
•When attaching the screw J, also attach the wire holder
together with it.
•After connecting the wires to the connectors CN192 and
CN193 on the power amplifier board, bundle them using
wire holder.
Fig.2-10
Fig.2-11
2.1.9 Removing the power amplifier board
(See Fig. 2-12.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
(1) Disconnect the wires from connectors CN192 and CN193
on the power amplifier board.
(2) Remove the two screws Mattaching the fan motor.
[Reference]
•It is not necessary to remove the wire from the fan
motor.
(3) Remove the two screws Nattaching the power amplifier
board.
(4) Lift the power amplifier board, disengage the hook efrom
the heat sink of the main board and take out the power am-
plifier board.
Fig.2-12

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2.1.10 Removing the power transformer
(See Fig. 2-13.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
(1) Disengage the wire clamp and tie band bundling the wires
of the power transformer.
(2) Disconnect the wire from connector CN192 on the power
amplifier board.
(3) Disconnect the wires from connectors CN191 and CN194
on the main board.
(4) Remove the two screws Pattaching the power transform-
er.
[Reference]
•After connecting the wires, bundling them using a wire
clamp and tie band. Fig.2-13
2.1.11 Removing the fan motor
(See Figs. 2-13 and 2-14.)
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
• Remove the front panel assembly.
(1) Disconnect the wire from connector CN181 on the main
board.
(2) From the right side of the main body, remove the two
screws Mattaching the fan motor.
[Reference]
After mounting the fan motor, treat the wire from the fan
motor as shown in fig. 2-13. Fig.2-14

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2.2 Front panel assembly section
• Remove the top lens. [VS-DT9R only]
• Remove the bottom panel.
• Remove the top panel.
• Remove the CD mechanism assembly.
• Remove the front panel assembly.
2.2.1 Removing the front switch board
(See Fig. 2-15.)
From the back side of the front panel assembly, remove the four
screws Qattaching the front switch board.
2.2.2 Removing the door switch board
(See Figs. 2-15 and 2-16.)
(1) From the back side of the front panel assembly, remove
the two screws Rattaching the door motor assembly.
(2) Remove the screw Sattaching the door switch board of
the door motor assembly.
2.2.3 Removing the door motor
(See Fig. 2-16.)
• Remove the door motor assembly.
(1) Remove the stop washers attaching the clutch assembly
and gear 2.
(2) Remove the clutch assembly, washer and Gear 2.
(3) Remove the two screws Tattaching the door motor.
2.2.4 Removing the front board
(See Figs. 2-17 to 2-20.)
(1) While widening section fof the front base in the direction
of the arrow, remove the rod gear assembly.
(2) Slide the moving panel assembly all the way in the direc-
tion of the arrow.
(3) While slightly widening section gtoward the front, take out
the moving panel assembly in the direction of the arrow.
(4) Remove the two screws Wattaching the moving base of
the moving panel assembly.
(5) Disengage the engagement sections hon the inside of the
moving base and at the inside of the moving panel assem-
bly and remove the moving base.
(6) Remove the two screws Xattaching the front board.
(7) Disengage the claw i of the moving panel and remove the
front board.
[Reference]
•Before attaching the moving base, pass the card wire of
the front board through the hole on the moving base. (See
Fig.2-19.)
Fig.2-15
Fig.2-16
Fig.2-17
Fig.2-18
Fig.2-19
Fig.2-20

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2.3 CD mechanism assembly section
2.3.1 Removing the LED board
(See Fig. 2-21.)
From the top side of the CD mechanism assembly, disengage
the claw aof the top chassis attaching the LED board and then
remove the LED board.
Fig.2-21
2.3.2 Removing the CD mechanism assembly
(See Fig. 2-22.)
(1) From the back side of the CD mechanism assembly, re-
move the three screws Aattaching the CD mechanism as-
sembly on the top chassis.
(2) Raise the protector in the direction of arrow and then re-
move the CD mechanism assembly.
Fig.2-22
2.3.3 Removing the CD servo board
(See Fig. 2-23.)
[Caution]
•Be sure to solder the short land section b on the flexible
wire before disconnecting the flexible wire from connec-
tor CN601 on the CD servo board.
If the flexible wire is disconnected without attaching sol-
der,thepickup unitmay bedestroyed bystatic electricity.
(1) From the back side of the CD mechanism assembly, at-
tach solder to the short land section bof the flexible wire
that is connected to the connector CN601 of the CD servo
board.
(2) Disconnect the flexible wire from connector CN601 on the
CD servo board.
(3) Disconnect the card wires from connectors CN611 and
CN612 on the CD servo board.
(4) Remove the two screws Battaching the CD servo board.
(5) Lift the front edge of the CD servo board slightly and dis-
engage it from the projection cand then from the engage-
ment section d.
[Caution]
•In the assembly, be sure to remove solder from the short
land section b after connecting the flexible wire. Fig.2-23

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2.3.4 Removing the traverse mechanism assembly
(See Fig. 2-24.)
• Remove the CD servo board.
(1) Remove the two screws Cattaching the CD servo board
bracket.
(2) Remove the two screws Dattaching the traverse mecha-
nism assembly.
(3) Disengage the claw eattaching the traverse mechanism
assembly and then take out the traverse mechanism as-
sembly.
Fig.2-24
2.3.5 Removing the pickup unit
(See Figs. 2-25 and 2-26.)
• Remove the CD servo board.
• Remove the traverse mechanism assembly.
(1) From the top side of the traverse mechanism
(1) assembly, remove the two screws Eattaching the
shaft.
(2) From the traverse mechanism assembly, disengage the
section fof the pickup unit and then remove the pickup unit
with the shaft.
(3) Pull the shaft out of the pickup unit.
(4) Remove the screw Fattaching the rack plate from the
pickup unit.
(5) Remove the screw Gattaching the P.S. spring from the
pickup unit.
Fig.2-25
Fig.2-26

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2.3.6 Attaching the pickup unit
(See Figs. 2-27 and 2-28.)
[Reference]
Refer to the explanation of "Removing the pickup unit" on
the preceding page.
(1) Attach the P.S. spring and rack plate to the pickup unit.
(2) Insert the shaft into the pickup unit.
(3) Engage the section fof the pickup unit with the traverse
mechanism assembly first, and set the both ends of the
shaft in the grooves gand h.
(4) After making sure that the section jof the rack plate is
meshed correctly with the middle gear, attach the shaft us-
ing the two screws E.
Fig.2-27
Fig.2-28
2.3.7 Removing the traverse mechanism board
(See Fig.2-29 .)
• Remove the CD servo board.
• Remove the traverse mechanism assembly.
(1) From the back side of the traverse mechanism assembly,
disconnect the feed motor wires that are soldered on the
traverse mechanism board.
(2) Remove the two screws Hattaching the traverse mecha-
nism board.
2.3.8 Removing the feed motor
(See Fig. 2-29.)
• Remove the CD servo board.
• Remove the traverse mechanism assembly.
(1) From the back side of the traverse mechanism assembly,
disconnect the feed motor wires that are soldered on the
traverse mechanism board.
(2) Remove the two screws Jattaching the feed motor.
Fig.2-29

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2.3.9 Removing the switch board
(See Fig.2-30.)
• Remove the CD mechanism assembly.
(1) From the top side of the CD mechanism assembly, re-
move the screw Kattaching the switch board.
(2) Lift the switch board slightly and then remove the wire from
connector CN101 on the switch board.
2.3.10 Removing the loading motor assembly
(See Figs.2-23, 2-30 to 2-32.)
• Remove the CD mechanism assembly.
(1) From the back side of the CD mechanism assembly, dis-
connect the card wire from connector CN612 on the CD
servo board. (See Fig.2-23.)
(2) From the top side of the CD mechanism assembly, re-
move the two screws Lattaching the clamper base as-
sembly.
(3) Disconnect the wire from connector CN101 on the switch
board while lifting the clamper base assembly slightly and
remove the clamper base assembly.
(4) Remove the three screws Mattaching the roller holder as-
sembly and take out the roller holder assembly.
(5) Disconnect the wires from connectors CN103 and CN104
on the loading motor assembly.
(6) Remove the belt of the loading motor assembly.
(7) Remove the two screws Nattaching the loading motor as-
sembly and take out the loading motor assembly.
Fig.2-30
Fig.2-31
Fig.2-32

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SECTION 3
Adjustment method
3.1 Flow of functional operation until TOC read

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3.2 Maintenance of laser pickup
(1) Cleaning the pick up lens
Before you replace the pick up, please try to clean the lens
with a alcohol soaked cotton swab.
(2) Life of the laser diode
When the life of the laser diode has expired,the following
symptoms will appear.
The level of RF output (EFM output : ampli tude of eye
pattern) will below.
(3) Semi-fixed resistor on the APC PC board
The semi-fixed resistor on the APC printed circuit board
which is attached to the pickup is used to adjust the laser
power. Since this adjustment should be performed to
match the characteristics of the whole optical block, do not
touch the semi-fixed resistor.
If the laser power is lower than the specified value, the la-
ser diode is almost worn out, and the laser pickup should
be replaced.
If the semi-fixed resistor is adjusted while the pickup is
functioning normally, the laser pickup may be damaged
due to excessive current.
3.3 Replacement of laser pickup

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SECTION 4
Description of major ICs
4.1 MN101CP30AKJ (IC701) : System control microcomputer
4.1.1 Terminal layout
4.1.2 Pin function
Pin No. Symbol I/O Function
1 THERM I Temperature detection, ON/OFF control of FAN_SW signal(pin 57)
2 KEY1 I Key switch input of the main body
3 KEY2 I Key switch input of the main body
4 VERSION I Switching signal for destination
5 GND - Ground
6 VREF+ - Reference voltage for A/D converter (Connect to VDD.)
7 VDD - Power supply for microcomputer
8 OSC2 O 8MHz main clock output
9 OSC1 I 8MHz main clock input
10 VSS - Ground for microcomputer
11 XI I 32.768kHz sub clock input
12 XO O 32.768kHz sub clock output
13 GND - Ground
14 CDTX O CD(FMU-F1) communication
15 CDRX I CD(FMU-F1) communication
16 FLRST O FL reset output
17 FLDATA I/O FL driver communication data input/output
18 FLCS O FL driver communication chip select output
19 FLCLK O FL driver communication clock output
20 STBLEDH O Standby LED for horizontal establishment (POWER_OFF/ON=H)
21 RST I Microcomputer reset input
22 STBLEDV O Standby LED for vertical establishment (POWER_OFF/ON=H)
23 FTU O Power supply for tuner
24 TUDATA I/O PLL input/output data (Connect to tuner.)
25 TUST O PLL strobe output (Connect to tuner.)
26 TUCK O PLL clock output (Connect to tuner.)
27 MPX I Stereo detection (Connect to tuner.), STEREO=L
28 RDSCK I RDS clock input (Connect to tuner.)
29 RDSI I RDS data input (Connect to tuner.)
30 REM I Remote controller input
31 GND - Ground
32 SMUTE O Mute signal, MUTE=L
33 AHB O Bass boost, ON=L, POWER_OFF=L
34 VOLDI O Data output (Connect to VOLUME_IC.)
35 VOLCE O Enable output (Connect to VOLUME_IC.)
36 VOLCL O Clock output (Connect to VOLUME_IC.)

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4.2 KIA78S06P (IC702) : Regulator
4.2.1 Terminal layout 4.2.2 Pin function
4.2.3 Block diagram
37 LOMUTE O Line out mute signal, MUTE=L
38 TREMCONT I Remote controller effective signal for horizontal establishment, L : effective state
39 - Not connect
40 H-V I Detecting signal for horizontal or vertical establishment
41 - Not connect
42 - Not connect
43 - Not connect
44 CDRSI O CD reset output (Connect to FMU-F1.)
45 - Not connect
46 BLCTL - Not connect
47 PSAVE O Power save mode ON/OFF signal, SAVE=H
48 FCD - CD power supply ON/OFF, not use
49 POUT O Main power supply ON/OFF
50 TOPLED1 O LED color control (Software PWN output)
51 TOPLED2 O LED color control (Software PWN output)
52 STBDIM I Dimmer control for STBYLED_H/V
53 DOOR1 I Moving panel position detecting signal, CLOSE=L
54 DOOR2 I Moving panel position detecting signal, OPEN=L
55 +BCTL O Unnecessary power supply cut-off signal for outage, Outage=H
56 BUP I Outage detecting signal (Backup mode)
57 FANSW O Fan motor ON/OFF signal
58 MT0 O Panel open (Motor driver)
59 MT1 O Panel close (Motor driver)
60 MTS O Panel action speed (Not use)
61 VREF- - Reference voltage for A/D converter (Connect to VSS.)
62 LOCK I Detection signal for panel action load
63 SAFETYCD I Detecting signal for CD abnormal voltage
64 SAFETY I Detecting signal for abnormal voltage
Pin No. Function
1 Output
2 Common
3 Input