PMC-D307L, PMC-D40L - Sony Audio Service Manual (repair manual). Page 15

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This adjustment is to be done when the optical pick-up is replaced.

1. Connect the oscilloscope TP (RF) and TP (VC) on the CD board.
2. Insert the disc (YEDS-18)  in and close the lid for CD.
3. Put the set into test mode. (See page 14.)
4. Press 

+ and = buttons to move the optical pick-up to the

center. (Move the optical pick-up to the music area on the disc
to enable easy visibility of the eye pattern.)

5. Press the 

( button.

From focus searching, focus is turned ON while entering
CLV drawing-in mode. Tracking and sled are turned OFF.

6. Press the 

( button.

[Both tracking and sled are turned ON.]

7. 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 (

≈

) in the

center of the waveform can be clearly distinguished.

VOLT/DIV : 0.2 V (With the 10:1 probe in use)
TIME/DIV  : 500 ns

1.3 

±

 0.2 Vp-p

+
–

CD board

TP (RF)

TP (VC)

oscilloscope

(AC range)

When observing the eye pattern, set the oscilloscope for AC
range and raise vertical sensitivity.

8. Release the test mode after adjustment is completed.

Adjustment Location: CD board (See page 17.)

Gain

Focus

Tracking

Symptoms

• The time until music starts becomes

longer for 

p

→

( on automatic

selection.

low

low or high

(

=, + buttons pressed.)

(Normally takes about 2 seconds.)

• Music does not start and disc

—

low

continues to rotate for 

p

→

( or

automatic selection.
(

=, + buttons pressed.)

• Sound is interrupted during PLAY.

Or time counter display stops

—

low

progressing.

• More noise during 2-axis device

high

high

operation.

A frequency response 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.