Sony CDP-590 - SECTION 4 ADJUSTMENTS; ELECTRICAL ADJUSTMENTS; RF LEVEL check; RF PLL Free-run Frequency Check

SECTION 4
ADJUSTMENTS
ELECTRICAL
ADJUSTMENTS
1. Perform
adjustments in the order given.
2.
Use YEDS-18 (Part No.
3-702-101-01)
disc unless other-
wise
indicated.
3. Use the oscilloscope with more
than lOMQ impedance.
RE
LEVEL check
This adjustment should
be
made after replacing the
Optical
Pick-up Block.
Procedure:
oscilloscope
(DC
range)
BO
board
TP^
o-
TP (VC)
o-
1. Connect oscilloscope to the test points TP (RF) and
TP (VC).
2. Turn POWER switch on.
3.
Put the disc (YEDS-18) in and press
0
button.
4. Confirm that an optimum waveform
eye
pattern.
Optimum eye
pattern
means
that shape
“O”
can be
clearly distinguished at the center of the waveform.
RF LEVEL
VOLT/OIV
: 200mV
TIME/DIV
; SOOnS
E-F Balance
Check
This
adjustment should
be
made
after replacing
the
Optical Pick-up Block.
Procedure:
BD
board
TP (TEO)
TP (VC)
oscilloscope
(DC range)
1. Connect the oscilloscope to
the test points TP (TEO)
and TP (VC).
2. Connect test point TP (ADJ)
to ground and TP (TES) to
TP
(VC)
with
lead wire.
3.
Turn
POWER switch
on.
4. Put the disc (YEDS-18) in and press 1>
button.
5. Confirm that the traverse waveform is symmetrical
above
and below.
6. After adjustment, remove the TP(ADJ), in
ground.
NOTE:Take sweep time as long as
possible to obtain best waveform.
\
A=B
VOLT/DIV ; IV
TIME/DIV:
1ms
RF
PLL
Free*run Frequency Check
Procedure:
main board
tpIpckT
frequency counter
1. Connect the frequency counter
to the test points
TP
(PCK) and TP (GND).
2.
Turn
POWER
switch
on.
3. Put the
disc (YEDS-18) in
and press
>
button.
4. Confirm that the reading
on the frequency counter
is locked at 4.3218 MHz.
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 adjust-
ment is not recomended generally to be performed.
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.
7
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