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– 9 –

1. Perform 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.

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

• Sled Motor Check
1. Press 

fl button, then press OFF button.

2. Press 

±, ≠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.
(Cancellation of BTL mute)

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

• Focus Search Check
1. Press 

fl button. (Focus search operation is performed continu-

ously.)

2. Look at the Optical pick-up objective lens and confirm that it

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

3. Press 

π button.

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

 When the malfunction is occurred by mis-passing

other buttons, turn off the power and check again
from making the test mode.

1. Make sure the POWER switch (S801) is off and then turn on the

power. (The LCD801 all light up.)

2. Set Test Mode by momentarily shorting both of the test mode

terminals with a jumper. (Shorting the terminals momentarily is
sufficient).

1. Press the FUNCTION switch (S809).
2. Turn the POWER OFF.

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

Adjustment Procedure :
1. Connect the oscilloscope to test point TP (VC) and TP (TO) on

MAIN board.

2. Put the set into test mode.
3. optical pick-up setting  to the center by 

± or ≠ button

pushing.

4. Insert disc (YEDS-18) and press 

fl button.

5. Adjust RV703 so that the oscilloscope traveres waveform is sym-

metrical, as shown in the figure below.

6. Release test mode after adjustment is completed.

Adjustment Location : Main board (See page 12)

A          

0V

B

C

VOLT / DIV : 1V
TIME / DIV :1ms

A = B

C = 180 – 420mV

TEST mode

Open : Normal mode
Short : Test mode

Jamper wire

TP (TO)

oscilloscope

(DC range)

TP (VC)

– 10 –

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

Adjustment procedure :
1. Connect the oscilloscope to test point TP (VC) and TP (RFO) on

MAIN board.

2. Put the set into test mode.
3. Optical pick-up setting to the center by 

± or ≠ button

pushing.

4. Insert disc (YEDS-18) and press 

fl button.

5. Press the 

fl button.  (Tracking servo ON)

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 (

◊

) 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.

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.

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 primary adjustment
are only a little different, return the controls to the origi-
nal position.

Procedure :
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) and press 

fl button.

3. Connect oscilloscope to TP (FO) and TP (VC) on MAIN board.
4. Adjustment RV702 on MAIN board so that the waveform is as

shown in the figure below. (Focus gain adjustment)

1.0 – 1.4 V 

VOLT/DIV : 0.2 V
TIME/DIV: 500 ns  

r

The time until music starts becomes
 longer for STOP 

→ 

fl

 

button or 

automatic selection.
( 

≠, ± buttons pressed.)

(Normally takes about 2 seconds.)

r

Music does not start and disc
continues to rotate for STOP 

→

fl

 

button or automatic selection.
( 

≠, ± buttons pressed.)

r 

Sound is interrupted during PLAY. 
Or time counter display stops
progressing.

r

More noise during 2-axis device
operation.

Symptoms

Gain

Focus

Tracking

low   

  low or high

–

           low

–

           low

high

            high

TP (RFO)

oscilloscope

(DC range)

TP (VC)

Adjustment Location : Main board (See page 12)

– 11 –

5. Connect oscilloscope to TP (TO) and TP (VC) on MAIN board.
6. Adjust RV704 on MAIN board so that the waveform is as shown

in the figure below. (Tracking gain adjustment)

VOLT/DIV : 1V
TIME/DIV : 2ms

• Incorrect Examples (fundamental waveform appears)

low tracking gain

VOLT/DIV : 1V
TIME/DIV : 2ms

high tracking gain

High fundamental wave

than for low gain

VOLT/DIV : 1V
TIME/DIV : 2ms

VOLT/DIV : 100mV
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

75mV

0V

200mV

0V

0V

0V

0V

(                                  )

100mV

0V

TP (TO)

TP (FO)

oscilloscope

(DC range)

TP (VC)

– 12 –

L4 : AM Frequency Coverage Adjustment

L2 : FM Frequency Coverage Adjustment

L1 : FM Tracking Adjustment

L3 : AM Tracking Adjustment

CT2 : AM Tracking Adjustment

CFT1 : AM  IF Adjustment

T1 : FM  IF Adjustment

CT1 : FM Tracking Adjustment

[TUNER BOARD]
(Component side)

RV702 : Focus Gain Adjustment

[MAIN BOARD]
(Component side)

RV703 : E-F Balance Adjustment

RV704 : Tracking Gain Adjustment

RV701 : Focus Bias Adjustment