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– 9 –

Note:
Tracking Balance Adjustment and Tracking Gain Adjustment are
done automatically in this set.

1. Press the CD LID OPEN/CLOSE DET switch (S424) on the

PUSH SWITCH board.

2. Under standby condition (when the clock appears in the dis-

play), short the BP (CD TEST AUTO).

 If the power is supplied to the microprocessor once, it is backed up

for 3 minutes, therefore the TEST mode will not be activated within
3 minutes even if the power is turned on again. In this case, short
instantaneously the BP (CD TEST MANUAL).

3. Press the  fl key, and the focus search is repeated.

At this time, check that the optical pick-up objective lens moves
smoothly without a sticking or noise.

4. Load the test disc (YEDS-18: Part No. 3-702-101-01), and per-

form automatic adjustment after the focus search succeeded.

5. After automatic adjustment is finished, move the sled motor

to the center. At this time, keep pressing the + and =
keys to confirm that optical pick-up moves smoothly via most
inside track 

→

 most outside track 

→

 most inside track with-

out a sticking or noise.

6. Confirm the traverse waveform.
7. Press the [WAKE UP TRACK] key.
8. The tracking servo and the sled servo are turned on, the mute

is cancelled.

9. Playback the 2nd track.
10. Adjust the RF and jitter waveforms.

Connecting points: MAIN Board (See page 12)

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

Adjustment Procedure:
1. Connect the oscilloscope to TP504 (VREF) and TP503 (RF)

on the MAIN board.

2. Insert the test disc (YEDS-18: Part No.3-702-101-01) and press

fl key to play.

3. Move the optical pick-up to the music area on the disc to en-

able easy visibility of the eye pattern by + or = key
pressing.

4. Adjust RV501 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.

Adjustment Location: MAIN Board (See page 12)

MAIN board

TP503 (RF)

TP504 (VREF)

+
–

oscilloscope

(AC range)

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

1.3 

±

 0.5 Vp-p

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

– 10 –

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 gain determines the optical 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 posi-
tions of the controls before performing the adjustment. If the posi-
tions after the primary adjustment are only a little different, return
the controls to the original position.

• The time until music starts becomes longer for

STOP 

→

 PLAY or automatic selection.

(=, + buttons pressed)
(Normally takes about 2 seconds)

• Music does not start and disc continues to

rotate for STOP 

→

 PLAY or automatic

selection.
(=, + buttons pressed)

• Sound is interrupted during PLAY.

Or time counter display stops progressing.

• More noise during 2-axis device operation

Gain

Focus

Symptoms

low

–

–

high

Procedure:
1. Keep the set horizontal.

If the set is not horizontal, this adjustment cannot be per-
formed due to the gravity against the 2-axis device

2. Insert the test disc (YEDS-18) and press the fl button.
3. Connect the oscilloscope BT (FEO) and TP504 (VREF) on

the MAIN board.

4. Adjustment RV502 on the MAIN board so that the waveform

is as shown in the figure below.

• Incorrect Examples (DC level changes more than on adjusted

waveform)

)

(

VOLT/DIV: 100 mV
TIME/DIV: 2 mS

100 mV

0 V

VOLT/DIV: 100 mV
TIME/DIV: 2 mS

200 mV

0 V

VOLT/DIV: 100 mV
TIME/DIV: 2 mS

75 mV

0 V

low focus gain

high focus gain

MAIN board

BP (FEO)

TP504 (VREF)

+
–

oscilloscope

Adjustment Location: MAIN Board (See page 12)

– 11 –

Procedure:
1. Connect the frequency counter as the above figures.
2. Adjust CT401 for 4.2495 MHz reading on the frequency

counter.

Specified Value: 4.2490 to 4.2500 MHz

+
–

adjustment

jig

10 : 1 probe

TP (+5 V)

TP401 (X2)

TP GND (SHIELD) 

+5
IN
GND

frequency counter

MAIN board

OUT
GND

 1 M

Ω

 100 k

Ω

 100 k

Ω

 +5 V

 0.5 pF

 47 uF

 IN

 GND

 1000 pF

 1 M

Ω

OUT

GND

INVERTER
(TC7W04F)

+

– 12 –

T1 AM IF Adjustment

CT401 Main Clock Adjustment

RV501 Focus Bias Adjustment

RV502 Focus Gain Adjustment

RV1 FM VCO Adjustment

L4 MW Frequency Coverage Adjustment

L2 FM Frequency Coverage 

Adjustment

L3-2
CT3

LW Tracking Adjustment

CT1
L1

FM Tracking Adjustment

BP (CD TEST AUTO)

BP (FEO)

BP (CD TEST MANUAL)

TP8
(VCO)

TP7
(+B)

TP12 (FM IN)

TP13 (FM IN GND)

TP50 (VT GND)

TP504 (VREF)

TP53 (VT )

TP503 (RF)

CT4 LW Frequency Coverage Adjustment

CT2
L3-1

MW Tracking Adjustment

TP (+5 V)

C429

TP GND
(SHIELD)

TP401

(X2)

+