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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.
(This regulation does not correspond to J and C version.)
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Conductive material
(conductive sheet) or iron plate
(caption)
Anti-static wrist strap
Short land
CN601
CD servo board
Flexible wire
5. 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 disconnected
from the connector on the CD pickup unit.
(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. 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.
Preventing static electricity
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 CD players.
Be careful to use proper grounding in the area where repairs are being performed.
2. About the earth processing for the destruction prevention by static electricity
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.
2-1 Ground the workbench
2-2 Ground yourself
Use an anti-static wrist strap to release any static electricity built up in your body.
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.)
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.
3. Handling the optical pickup
1.
2.
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.
4. Handling the traverse unit (optical pickup)
1.
2.
3.
4.
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1. Terminal layout 2. Block diagram
3. Pin function
AN22000A (IC601) : RF & Servo amplifier
A C B D PDE PDF VREFGND VCC TEN
TEBPF TEOUTVDET
FEOUT /RFDET 3TOUT
CEA
OFTR
COFTR
BDO
CBDO
ARF
C.AGC
RFNFEN
RF_EQAGC BDO OFTR 3TENV
NRFDET
GCABCA
RF OUTRF IN
SUBT SUBT
GCTRL TBAL FBAL
163
14
13
12
11
4
17
PD LD
VDET
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16 32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
5
6
7
825
26
24
9 10 15 22 23 21 20 19 18 2 1
28
27 29 30 31 32
GCABCA GCABCA
AMPGCABCA AMP AMP AMP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32PD
LD
VCC
RFN
RF OUT
RF IN
C.AGC
ARF
CEA
3TOUT
CBDO
BDO
COFTR
OFTR
/RFDET
GND
VREF
VDET
TEBPF
TEOUT
TEN
FEN
FEOUT
GCTRL
FBAL
TBAL
PDE
PDF
D
B
C
AAPC Amp. Input terminal
APC Amp.Output terminal
Power supply terminal
RF addition Amp.Reversing input terminal
RF addition Amp.Output terminal
AGC input terminal
Terminal of connection of capacity of AGC loop filter.
AGC output terminal
Capacity connection terminal for HPF-Amp.
3TENV output terminal
Capacity connection terminal for RF shade side envelope detection
BDO output terminal
Capacity connection terminal for RF discernment side envelope detection
OFTR output terminal
RFDET output terminal (Negative logic)
Earth terminal
VREF output terminal (Not use)
VDET output terminal (Not use)
VDET input terminal
TE Amp. output terminal
TE Amp. reversing input terminal
FE Amp. reversing input terminal
FE Amp. output terminal
Terminal GCTL & APC
FBAL control terminal
TBAL control terminal
Tracking signal input terminal 1
Tracking signal input terminal 2
Focus signal input terminal 4
Focus signal input terminal 2
Focus signal input terminal 3
Focus signal input terminal 1
Pin No. Symbol Function
