Table of Contents
Advertisement
SECTION
2
ADJUSTMENTS
JSTMENTS
its in the order given.
t No, 3-702-101-01)
disc unless
1,
ype with more than 10MQ
im-
djustment/Lock Frequency
frequency counter
| TP (ASY).
uency counter to the test points
(GND).
tch on.
©
that
the reading
on
the fre-
4.3218MHz +30kHz.
ency adjustment)
iding wire from TP (ASY).
S-18) in and press
p button.
reading on the frequency counter
8 MHz.
3218MHz
+30kHz
Focus Bias Adjustment
This adjustment
should
he made
after replacing
the Optical Pick-up Block.
Procedure:
oscilloscope
(OC range)
main board
C)
TP (RF) O————-O+
1P (RFG) o-
—_———lo-
1. Connect
oscilloscope to the test points TP (RF)
and TP (RFG).
2. Turn POWER switch on.
3. Put the disc (YEDS-18) in and press > button.
4. Adjust RV104
for an optimum waveform eye pat-
tern. Optimum eye pattern means that shape "©"
can
be clearly distinguished at the center of the
waveform.
WERE
Wii
1.1-1.5 Vp-p
-0.1-0.05V
vent
should
be made
after replacing
Block.
oscilloscope
(DC range)
e
IO
1. Connect
the
oscilloscope
to the test points
TP
(TEO) and TP (GND).
2. Ground TP (ADJ ) to set an adjustment mode.
3. Ground TP(TES) and turn POWER switch on.
4. Put the disc (YEDS-18) in and press
> button.
5
. Adjust RV101 so that positive and negative halves of
traverse waveform have the same amplitudes.
6. After adjustment, cancel the adjustment mode.
VOLT/DIV:
1V
TIME/DIV:
1ms
Focus/Tracking Gain Adjustment
A
frequency
response
analyzer
is necessary
in
order to perform this adjustment exactly.
However,
this gain has a margine, so even if it is
slightly off, there is no problem. Therefore, this ad-
justment
is not
recomended
generally
to
be per-
formed.
Focus/tracking gains determine the pick-up follow-
up
(vertical. and horizontal)
relative
to mechanical
noise
and mechanical shock
when the 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.
low or high
e The time until music starts
becomes longer for STOP
> DPLAY or automatic
selection (Ke4 PPI buttons
pressed. (Normally takes
about 2 seconds.)
e Music does not start and
disc continues to rotate
for STOP >DPLAY or
automatic selection (hed
bPt buttons pressed.)
@ Disc table opens shortly
after STOP>DPLAY.
e Sound is interrupted dur-
ing PLAY.
Or time count-
er display stops progress-
low or high
low
ing
@ More poise during 2-axis
high
high
device operation.
The following is a simple adjustment method.
— Simple Adjustment —
Note:
Since exact adjustment cannot be performed, remem-
ber the positions of the controls before performing the
adjustment.
If the positions after the simple adjust-
ment are only a little different, return the controls to
the origina! position.
oscilloscope
(DC range)
Procedure:
main board
———
TP (FEI) SS
+
{
TP (FEO)
1
=
TP (TE!) Que
-
TP (TEO)
1. Keep the set flat.
If the
set
is not
horizontal,
this adjustment
cannot be performed due to the gravity against
the 2 axis device.
2. Insert
the
disc (YEDS-18)
and
press
>
PLAY
button.
3. Connect
the
oscilloscope
to
TP
(FEI)
and
TP
(FEO).
4. Adjustment
RV103
so that
the waveform
is as
shown
in the picture
below.
(focus gain adjust-
ment)
VOLT/DIV:
100mV
TIME/DIV:
2mS
—100mvV
—oOv
@
Incorrent
Examples
(DC level is quite different
from the adjusted waveform) (below)
low focus gain
TIME/DIV:
2mS
—OvV
high focus gain
VOLT/DIV:
100mvV
TIME/DIV: 2mS
—100mvVv
—75mvV
—oOv
VOLT/OIV:
100mV
5. Connect the oscilloscope to TP (TEI), TP (TEO).
6. Adjust RV102 so that the waveform is as shown
the picture below. (tracking gain adjustment)
@
Incorrect Examples (fundamental wave appears)
low tracking gain
high tracking gain
(higher frequency of the fundamental wave
than above)
Adjustment Location:
main board
TP (RFG)
| vr, (R
TP
(TEO)
TP (ASY)
TP (GND)
TP (TEI)
ie
<n (TES)
RV103
10202
TP (FEO)
P (FEI)
-— Component Side —
Advertisement
Table of Contents
