Read Sony CFD-575 / CFD-577 Service Manual online
– 11 –
The following is a simple adjustment method.
– Primary Adjustment –
Note :
Since exact adjustment cannot be performed, re-
member the positions of the controls before per-
forming the adjustment.If the positions after the
primary adjustment are only a little different, re-
turn the controls to the original position.
forming the adjustment.If the positions after the
primary adjustment are only a little different, re-
turn the controls to the original position.
Procedure :
1. Keep the set horizontal.
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.
due to the gravity against the 2-axis device.
2. Insert disc (YEDS-18) and press
^ button.
3. Connect oscilloscope to TP (FO) and TP (VC) on CD board.
4. Adjustment RV702 on CD board so that the waveform is as
4. Adjustment RV702 on CD board so that the waveform is as
shown in the figure below. (Focus gain adjustment)
VOLT/DIV : 100mV
TIME/DIV : 2ms
TIME/DIV : 2ms
• Incorrect Examples (DC level changes more than on adjusted
waveform)
VOLT/DIV : 100mV
low focus gain
TIME/DIV : 2ms
VOLT/DIV : 100mV
high focus gain
TIME/DIV : 2ms
6. Adjust RV701 so that the oscilloscope waveform is as shown in
the figure below (eye pattern).
A good eye pattern means that the diamond shape (
A good eye pattern means that the diamond shape (
◊
) in the cen-
ter of the waveform can be clearly distinguished.
7. Release test mode after adjustment is completed.
• RF signal reference waveform (eye pattern)
When observing the eye pattern, set the oscilloscope for AC range
and raise vertical sensitivity.
and raise vertical sensitivity.
[CD BOARD] (Conductor side)
Adjustment Location : CD board (See page 12)
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.
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.
1.2
±
0.2V
VOLT/DIV : 0.2V
TIME/DIV: 500ns
TIME/DIV: 500ns
IC701
TP (VC)
TP (RFO)
+
-
TP (RFO)
oscilloscope
(DC range)
TP (VC)
r
The time until music starts becomes
longer for STOP
longer for STOP
→
^
button or
automatic selection.
(
(
=, + buttons pressed.)
(Normally takes about 2 seconds.)
r
Music does not start and disc
continues to rotate for STOP
continues to rotate for STOP
→
^
button or automatic selection.
(
(
=, + buttons pressed.)
r
Sound is interrupted during PLAY.
Or time counter display stops
progressing.
Or time counter display stops
progressing.
r
More noise during 2-axis device
operation.
operation.
Symptoms
Gain
Focus
Tracking
low
low or high
–
low
–
low
high
high
100mV
0V
200mV
0V
75mV
0V
Click on the first or last page to see other CFD-575 / CFD-577 service manuals if exist.