Sony CDP-557ESD - Distortion Adjustment; Focus;Tracking Gain Adjustment

Distortion Adjustment
This adjustment should be made only when
replacing D/A converter and components of the
—15 V system power supply block.
‘distortion meter
LINEOUT
. Put disc (YEDS-18) in and playback 1 kHz, 0 dB
signal track (second track).
. Adjust the following volumes in order given by
atrows so that the distortion is minimum.
L-CH: RV404 > RV403 > RV401 > RV402
R-CH: RV504 > RV503 > RV501 > RV502
. Confirm the specification is satisfied. When out of
specification, repeat item 2 and 3 several times.
Specification: 0.003% and below
Adjustment Location: main board
RV501 RV502 RV403 RV402
Oo O Oo O
0 oO 90 9
RV504 RV503 RV404 RV401
CDP-557ESD/707ESD
CDP-557ESD/707ESD
REFERENCE
Focus/Tracking Gain Adjustment
A frequency responce 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. Therefore, do not
perform this adjustment.
Focus/tracking
gain
determines
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, mechanical shock and
skipping occurs more easily.
@
When
gain
adjustment
is
off,
the
symptoms
below
appear.
Tracking
e The time until music starts
becomes longer for STOP
> DPLAY or automatic
selection (Ke4, PPI buttons
pressed.) (Normally takes
about 1 seconds.)
e Music does not start and
disc continues to rotate
for STOP >PPLAY or
= _
automatic selection. (h4
PPI buttons pressed.)
e Disc table opens shortly high
after STOP>DPLAY.
e Sound is interrupted dur-
ing PLAY. Or time count-
er aed stops progress-
e
More
noise
during
2-axis
high
high
device
operation.
The following is a simple adjustment method.
— Primary Adjustment —
Note: Since exact adjustment cannot be performed, remem-
ber the positions of the controls before performing the
adjustment. If the positions after the primary adjust-
ment are only a little different, return the controls to
the
original
position.
oscilloscope
(DC
range)
Procedure:
digital
board
[enti
TP
FE
OO
HH
ee
TP
TEOm-
-
1. Keep the set horizontal.
If
the
set
is
not
horizontal,
this
adjustment
cannot
be
performed
due
to
the
gravity
against
the 2 axis device.
2. Put set in adjustment mode. (See page 7.)
3. Insert disc (YEDS-1) and press ® PLAY button.
4. Connect oscilloscope to servo board TP FE.
5.
Adjustment
RV103
so
that
the
waveform
is
as
shown
in
the
figure
below.
(focus
gain
adjustment)
VOLT/DIV: 100mV
f TIME/DIV: 2mS
@ Incorrent Examples (DC level changes more than
on adjusted waveform)
low focus gain
VOLT/DIV: 100mvV
TIME/DIV: 2mS
—OV
high
focus
gain
VOLT/DIV:
100
mV
y TIME/DIV: 2mS
6. Connect oscilloscope to main board TP TE.
7. Adjust RV102 so that the waveform is as shown in
the figure below. (tracking gain adjustment)
VOLT/DIV: 1V
TIME/DIV: 2mS
OV
@ Incorrect Examples (fundamental wave appears)
low tracking gain
VOLT/DIV: 1V
TIME/DIV: 2mS
— OV
high tracking gain
(higher fundamental wave than for low gain)
VOLT/DIV: 1V
TIME/DIV: 2mS
—— OV
Adjustment Location: digital board
A oof
Oo
RV103 \ (re)
RV102
(FE)