Sony CDP-S37 - Page 5

REFERENCE
Focus/Tracking Gain Adjustments
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 adjust-
ment.
Focus/tracking gain determines the pick-up follow up (ver-
tical and horizontal) relative to mechanical noise and 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 oper-
ates increases.
@When gain is lowered, mechanical shock and skipping
occurs more easily.
@ When gain adjustment is off, the symptoms below appear.
symptoms Tracking
@ The time until music starts
becomes longer fori ~>
or automatic
selection. (Kid, DDI
buttons pressed.)(Normal-
ly takes about 1 seconds.)
low or high
@Music does not start and
disc continues to rotate for
@—>> or automatic selec-
tion.
(Kil, DDI buttons pressed.)
@Disc table opens shortly
after >>.
low or high
@Sound is interrupted during
PLAY or time counter dis-
play stops progressing.
@More noise during 2-axis
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 position after the primary adjust-
ment are only a little different, return the controls to
the original position.
Procedure:
oscilloscope
(DC range)
main board C)
TP (FEO) So +
t _
TP (TEO) Omm- -7 |
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. Insert disc (YEDS-18: Fifth Selection) and press > but-
ton.
3. Connect oscilloscope to main board TP (FEO).
4. Adjust RV3 so that the waveform is as shown is the
figure below. (focus gain adjustment)
5. Connect oscilloscope to main board TP (TEO).
6. Adjust RV5 so that the waveform is as shown is the
figure below. (tracking gain adjustment)
VOLT /DIV
TIME /DIV
ov
e@ Incorrent Examples (DC level changes more than on adjust-
ed waveform)
low focus gain
OV
high focus gain
TIME /DIV :
75m
ov
VOLT/DIV :
TIME /DIV : 2mS
: 100mV
: 2msS
100mV
: 100mv
250mV
VOLT/DIV : 100mV
2ms
100mV
v
TIME /DIV
ov
e Incorrect Examples (fundamental wave appears)
low tracking gain
TIME /DIV
ov
high tracking gain
higher fundamental wave than for low gain)
ov
Adjustment Location : main board
TRACKING GAIN
ADJ
RV5, TEO
VOLT/DIV :
VOLT /DIV :
VOLT/DIV :
TIME/DIV :
SECTION 3
DIAGRAM
3-1. SEMICONDUTOR LEAD LAYOUTS
1v
: 2ms
2SK381-C
RD6.8FS-B1
1V
: 2ms saincge
K
1V
2ms 10E2
i athoge
a
\
anode
ot FOCUS GAIN
FEO ADJ