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Approval Judgement of defect for Optical Pick-up
Note:
Before adjustment of the optical
pick-up, following this chart.
l
S
Out of Focus
Servo
A.A.C,
Check the DC voltage
(5V) from CN102
pin 1 on optical
servo P.C,B.
P.D.
1C101, Wire short
A.A.C.
YES
Visually check the
operation of the
focus lens up-down
about 5 sec.
(no nead a disc)
Check the sawtooth
waveform
from
CN101
pin 6 of
optical servo P.C.B.
YES
Check the coil
resistance (30Q)
from CN101
pin 5, 6
of optical servo P.C.B.
YES
Check the DC voltage
of R107 both ends of
optical servo P.C.B.,and
confirm the potential
difference about 0.5V.
P.D.
If DC voltage is
about 1.0V, should
be laser was snaped.
YES
Check the Focus
balance from TJ101 on
optical servo P.C.B by
oscilloscope
(200mV/Sms DIV AC)
Need a Focus balance
adjustment.
Refer to page 3.
YES
P.D.
;
Electric circuit
(mainly optical servo
P.C.B.1.
Connect the oscilloscope to
TJ402 pin of main P.C.B.
(500mV/0.5usec DIV AC)
Place the disc into the
disc holder and apply
power to the unit and
select the play mode.
P.D.
Electric circuit
A.A.C.
Replace the
optical pick-up
Part No.
SRLPOO7NO1A
Replace the
optical pick-up
Part No.
SRLPOO7NO1A
Replace the
optical pick-up
Part No.
SRLPOO7NO1A
Caution:
It is very dangerous to look at or touch the
laser beam.
(Laser radiation is invisible.)
Check the TTON signal
(L) from CN412
pin 6.
Possible Defect.
And Associated Components.
Focus servo "'OK"'
(but NO TOC or
Noisey)
Check the RF best eye
signal from TJ402 pin
of main P.C.B.
(500mV /0.5usec.
DIV AC)
P.D.
YES
Electric circuit
(specialy pick-out or
PLL circuits)
NO
Check the RF -
amplitude (1.5 ~
3.0Vp-p) from TJ402
pin of main P.C.B.
(500mV /0.S5usec
DIV AC)
YES
If lese than
1.5Vp-p
should be laser diode
become worst.
Mechanical adjustment
require.
(Refer to page 23, and
confirm the RF best
eye signal).
Replace the
optical pick-up
Part No.
SRLPOO7NO1A
YES
Grating adjustment
require.
(Refer to page 23, and
confirm the '"'N" mark
waveform).
Replace the
optical pick-up
Part No.
SRLPOO7NO1A
Replacement Procedure
1. Mount the traverse unit on the traverse unit base, and
make sure mounting screw is tight.
2. Position the assembly as shown in Fig. 1.
3. Remove the optical bracket and screw from the optical
pick-up body as shown in Fig. 2.
Note:
A) Be. careful when
removing the screw, the spring
can snap out very fast and be lost.
B) Also_note the
position
of the spring so that
when ready to re-assembly it, you will remember
its position.
Phe,
wae ee eee
wl
4, Remove
the shaft clamp mounting screw as shown
in
Fig. 3 .
5. Remove the two suspension shafts by lifting and pulling
to the left.
Optical pick-up body can be separated from
the deck as shown in Fig.3.
|
6. Before proceeding to replace the optical pick-uip, observe
the following precautions:
A)
The laser diode can be destroyed
if P101
remains
open too long (about 20 seconds).
Do not
remove
the shorting pin from
P101
until
you are ready to connect it to 03 module CN101 as
shown in Fig. 4.
B)
Be certain that rest detection switch (S101) and end
detection switch (S102) have not been bent.
If they
have, traverse motor will remain on. (Fig. 5)
7. Reassemble the optical pick-up to the traverse unit by
. following step 6 through 1 in reverse procedure.
..----— Clamp mounting screw
Optical pick-up body
Turntable
Suspension shaft
[Fig. 3]
* For servicing of traverse unit, refer to page 1.
Optical servo P.C.B.
Traverse
(03 PCB.)
unit base
Fig. 1
Focus lens
$102
AARVAARAS
LLB
ASLARS
ROUND
AAEM
tana
die tae
$101
Traverse
motor
11 module
(Spindle motor drive coil module)
Bottom
view of traverse unit
Fig. 5
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