ADJUSTMENT
2
@O@
[A]MAIN
C.B
(PATTERN
SIDE)
Note:
Connect
probe(10:1)
of
frequency
counter
and
oscilloscope
to
test
point.
@
VCO
Frequency
Adjustment
1.
Open
the
tray
by
pressing
the
OPEN/CLOSE
button.
2,
Short
between
test
points
TP6
(ASY)
and TP4
(GND)
using
a
short
lead
wire.
3.
Connect
the
frequency
counter
to
TP1
(VCO)
and
TP2
(GND).
4,
Adjust
SFR403(VCO)
so
that
the
frequency
counter
readings
is
4.35
+
0.05
MHz.
5.
After
this
adjustment,
remove
the
short
lead
wire
from
TP6
(ASY)
and
TP4
(GND).
@
Focus
Bias
Adjustment
Make
the
focus
bias
adjustment
when
replacing
and
repairing
the
optical
block.
Oscilloscope
(DC
range)
MAIN
C.B
ewan
TP7(RF)
©
TP8(GND)
©
1,
Connect
the
oscilloscope
to
TP7(RF),
TP8(GND).
2.
Turn
on
the
power
switch.
3.
Insert
the
disc
YEDS-18
(YEDS-1)
and
play
back
the
second
track.
4,
Adjust
SFR452(F.B)
to
make
clear
and
maximize
the
waveform,
diamond
shapes
(©)
can
be
distinguished
in
the
center
of
the
waveform
RF
signal
waveform
LIVI
XY
YSSVAY/
VY
WER
RNR
MAX.
0,9,0.4,
VOLT/DIV
:
20nV
TIME/DIV
:
O0.5usec
@
RF
Waveform
Check
This
check
should
be
performed
whenever
the
optical
system
block
is
replaced.
1.
Connect
the
oscilloscope
to
TP7
(RF)
and
TP8
(GND).
2,
Turn
the
power
switch
on.
13
3.
Insert
the
disc
YEDS-18
(YEDS-1)
and
play
back
the
data
on
the
second
track.
4.
Adjust
SFR
in
pickup
so
that
the
waveform
on
the
oscilloscope
is
as
shown
in
the
figure
below.
RF
signal
waveform
YY
XK
KKK
RK
e%
KK)
0°04.
0-0,0,0'0'0'0.6.4
ERR
9.9,0.9-6,9,9,9.9,9,9,9.95
1.4
+
0.3
Vp-p
Ov
VOLT/DIV:
20
mV
TIME/DIV:
0.5sec
Note:
The
current
of
the
laser
signal
can
be
checked
by
checking
the
voltage
across
R458(10Q).
The
specified
current
value
is
shown
on
the
label
of
the
pickup.
The
difference
should
be
+
6.0
mA.
KSS-150A
30Y98
K447
44.7
mA
Voltage
across
R458
L
urrent
Jop
=
aser
c
n
Pp
100
@®
Tracking
Balance
Adjustment
Oscilloscope
(DC
range)
MAIN
C.B
a
TPII(T
IN)o
TP10(GND)°
Connect
the
oscilloscope
to
TP1I(T
IN),
TPIO(GND).
Connect
a
center
of
SFR401(TE)
to
ground.
Turn
on
the
power
switch.
Insert
disc
YEDS-18
(YEDS-1)
and
press
the
[>PLAY
button.
5.
Adjust
SFR451(TB)
so
that
the
waveform
on
the
oscilloscope
is
vertically
symmetrical
as
shown
in
the
figure
below.
mm
0
0 =
[rr
oe
er)
A
0
+
20mV,
A=B
B
VOLT/DIV
:
20mV
TIME/DIV
:
2msec
6.
After
adjustment
is
completed,
remove
the
ground
lead
wire.
Focus/Tracking
Gain
Adjustment
A
frequency
responese
analyzer
is
necessary
in
order
to
perform
this
adjustment
exactly.
However,
this
gain
has
a
margin,
so
even
if
it
is
slightly
off,
there
is
no
problem.
Therfore,
do
not
perform
this
adjustment.
Focus/tracking
gain
detemines
the
pick-up
follow-up
(vertical
and
horizontal)
relative
mechanical
noise
and
mechanical
shock
when
2-axis
device
operate.
However,
as
these
reciprocate,
the
adjustment
is
at
the
point
where
both
are
satisfied.
@
When
gain
is
raised,
the
noise
when
the
2-axis
device
operates
increases.
@
When
gain
is
lowered,
it
is
more
susceptible
to
mechanical
shock
and
skipping
occurs
more
easily.
@
When
gain
adjustment
is
off,
the
symptoms
below
appear.
Focus
Symptoms
@
The
time
until
music
starts
Tracking
becomes
longer
for
STOP
>>
PLAY
or
automatic
selection
(44,
DH
buttons
pressed.
)
(Normally
takes
about
2
seconds.
)
low
or
high
@
Music
does
not
start
and
disc
continues
to
rotate
for
STOP
—
PPLAY
or
automatic
selection
(144,
Dp
buttons
pressed.
)
@
Disc
table
opens
shortly
after
STOP
—
PPLAY.
eee
@
Sound
is
interrupted
during
PLAY.
Or
time
counter
display
stops
progressing.
@
More
noise
during
2-axis
device
operation.
The
following
is
a
simple
adjustment
method.
