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– 17 –

1. Perform Traverse adjustment in test mode.

After adjustment, be sure to release test mode.

2. Perform adjustments in the order given.
3. Use the disc (YEDS-18, Part No. 3-702-101-01) only when so

indicated.

4. Short the both sides of R720 on the CD board for stop operation of

anti-shock circuit. (See page 20.)

• Switch position
FUNCTION switch : CD

1. Short the solder bridge the TP (TEST) on the CONTROL board.
2. Insert the AC power plug.

  Release the shorted solder bridge the TP (TEST), the test mode is
  release.

Put the set into test mode and perform the following checks. Repair
if there are any problems.

Press the 

±, ≠ buttons and confirm that the optical pick-up

moves smoothly from the innermost to outermost circumference and
back smoothly and with no catching or abnormal noises.

± : Optical pick-up moves to the outer circumference
≠ : Optical pick-up moves to the inner circumference

1. Push the 

fl button. (Focus search operation is performed

continuously.)

2. Look at the optical pick-up objective lens and confirm the it moves

up and down smoothly, with no catching or abnormal noises.

3. Push the 

π button.

Confirm that focus search operation stops. If it does not, push the
π button again longer.

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

1. Connect the oscilloscope between TP (TE) and TP (VC).
2. Put the set into test mode.
3. Push the CD lid to open and insert disc (YEDS-18).
4. Close the CD lid.
5. Press the 

± and ≠ buttons to move the optical pick-up to

the center.

6. Push the 

fl button.

7. Push the 

π button.

8. Push the 

fl button.

9. Adjust RV703 so that the oscilloscope traverse waveform is

symmetrical, as shown in the figure below.

10. Release test mode after adjustment is completed.

–control board (conductor side) –

IC801

25

24

TP

(TEST)

oscilloscope

(DC range)

CD board

TP (TE)(IC701 

$¢

)

TP (VC)(IC701 

$•

)

Adjustment Location : See page 20.

0V

A=B

A

B

– 18 –

• The time until music starts becomes longer

for 

π m fl on automatic selection.

(

≠, ± buttons pressed.)

(Normally, takes about 2 seconds.)

• Music does not start and disc continues

to rotate for 

π m fl or automatic

selection.
(

≠, ± buttons pressed.)

• Sound is interrupted during PLAY. Or

time counter display stops progressing.

• More noise during 2-axis device

operation.

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

1. Connect the oscilloscope between TP (RF) and TP (VC).
2. Insert disc (YEDS-18) and push the 

fl button.

3. Adjust RV701 so that the oscilloscope waveform is maximum as

shown in the figure below (eye pattern).

• RF signal reference waveform (eye pattern)

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 raised, the noise when the 2-axis device operates

increases.

• When gain is lowered, it is more susceptible to machanical shock

and skipping occurs more easily.

When gain adjustment is off, the symptoms below appear.

oscilloscope

(DC range)

CD board

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

Adjustment Location : See page 20.

low

low or high

low

low

high

TP (RF)(IC702 

!¢

)

TP (VC)(IC701 

$•

)

0V

1.3 ± 0.2 V

VOLT / DIV : 0.2 V
TIME / DIV : 500 nS

–

–

high

– 19 –

The following is a simple adjustment method.

Since exact adjustment cannot be performed, remember the
positions of the controls before performing the adjustment.
If the positions after the simple adjustment are only a little
different, return the controls to the original position.

1. Keep the set horizontal.

If the set not horizontal, this adjustment cannot be performed due
to the gravity against the 2-axis device.

2. Insert disc (YEDS-18) and push the 

fl button.

3. Connect the oscilloscope between TP  (FE) and TP (VC).
4. Adjustment RV702 so that the waveform is as shown in the figure

below. (focus gain adjustment)

• Correct Example

5. Connect the osilloscope between TP (TE) and TP (VC).
6. Adjust RV704 so that the waveform is as shown in the figure below.

(tracking gain adjustment)

• Correct Example

oscilloscope

(DC range)

CD board

TP (FE)(IC701 

1

)

TP (TE)(IC701 

$¢

)

TP (VC)(IC701 

$•

)

• Incorrect Examples (DC level changes more than on adjusted
  waveform)

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

100 mV

0 V

250 mV

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

75 mV

100 mV

• Incorrect Examples (fundamental wave appears)

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

0 V

0 V

VOLT/DIV : 100 mV
TIME/DIV : 2 mS

Adjustment Location : See page 20.

low focus gain

high focus gain

low tracking gain

high tracking gain

(higher fundamental wave than for low gain)

– 20 –

Adjustment Location : CD board (conductor side)

TRACKING GAIN

ADJ

RV704

FOCUS GAIN

ADJ

RV702

TRAVERSE

ADJ

RV703

FOCUS BIAS

ADJ

RV701

TP

(FE)

TP

(VC)

TP

(TE)

R720

IC701

TP

(RF)