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– 9 –

• Switch location

FUNCTION

: RADIO

VOLUME

: MAX

MEGA BASS

: mechanical center

ROTARY  EQUALIZER : center click

BAND : AM

BAND : FM

• Repeat the procedures in each adjustment several times, and the

frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.

Adjust for a maximum reading on level meter.

CFT1

455kHz

Adjust part

Frequency display

Reading on digital

voltmeter.

Confirmation

530kHz

0.9 ± 0.2V

L4

1,710kHz

5.6 ± 0.2V

Adjust for a maximum reading on level meter.

L3

620kHz

CT2

1,400kHz

Adjust part

Frequency display

Reading on digital

voltmeter.

Confirmation

87.5MHz

1.7 ± 0.2V

L2

108MHz

4.0 ± 0.2V

Adjust for a maximum reading on level meter.

L1

87.5MHz

CT1

108MHz

Adjustment Location : MAIN board (See page 12)

       [MAIN BOARD]
       (Conductor side)

AM  RF signal
generator

30% amplitude modulation by 400Hz
signal.
Output level : as low as possible

Put the lead-wire
antenna close to 
the set.

FM RF signal
generator

22.5kHz frequency deviation by 400Hz signal.
Output level : as low as possible

telescopic
antenna
terminal

0.01

µ

F

set

32

Ω

+

–

J302(phones)

level meter

R3

C83

+

–

Digital voltmeter

(DC range)

3. Phase Check

Mode : Playback

4. After the adjustment, lock the screws with locking compound.

V

H

in phase

90

°

45

°

135

°

180

°

good

wrong

set

L-CH

R-CH

screen pattern

test tape
P-4-A063
(6.3kHz, –10dB)

Osilloscope

J302 (phones)

32 

Ω

32 

Ω

Deck A

Deck B

Window (C)
cassette

Screwdriver

Window (C)
cassette

– 10 –

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 

^ 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 

^ 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 

p button.

Confirm that focus search operation stops. If it does not , press
p 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. Short-circuit between JW804 and JW812 on the switch board.
2. Turn the POWER ON.
3. Open the Short-circuit.

[SWITCH BOARD] (Conductor side)

1. Turn the POWER OFF.

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

Adjustment Procedure :
1. Connect the oscilloscope between TP (VC) and TP (TO) on CD

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 

^ 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.

[CD BOARD] (Conductor side)

Adjustment Location : CD board (See page 12)

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

CD 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 

^ button.

5. Press the 

^ button.  (Tracking servo ON)

A          

0V

B

C

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

A = B

C = 350mV 

±

 120mV

IC701

TP (VC)

TP (TO)

+

-

TP (TO)

oscilloscope

(DC range)

TP (VC)

TP

(TEST 1)

JW804
JW812

TEST Portion
Short : Test mode
Open : Normal mode

– 11 –

The following is a simple adjustment method.

 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.

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 

^ 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

shown in the figure below. (Focus gain adjustment)

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

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.

[CD BOARD] (Conductor side)

Adjustment Location : CD board (See page 12)

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.

1.2 

±

 0.2V 

VOLT/DIV : 0.2V
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 

→

^

 

button or 

automatic selection.
( 

=, + buttons pressed.)

(Normally takes about 2 seconds.)

r

Music does not start and disc
continues to rotate for STOP 

→

^

 

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

100mV

0V

200mV

0V

75mV

0V

– 12 –

IC701

TP (FO)

TP (VC)

TP (TO)

+

-

TP (TO)

TP (FO)

oscilloscope

(DC range)

TP (VC)

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

the figure below. (Tracking gain adjustment)

7. Release test mode after adjustment is completed.

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

0V

0V

0V

(                                  )

CT2 : AM Tracking Adjustment

CT1 : FM Tracking Adjustment

L1 : FM Tracking Adjustment

CFT1 : AM IF Alignment

L3 : AM Tracking Adjustment

L4 : AM Frequency Coverage Adjustment

L2:FM Frequency Coverage Adjustment

[MAIN BOARD] (Component side)

[CD BOARD] (Component side)

RV702 : Focus Gain Adjustment

RV703 : E-F Balance Adjustment

RV704 : Tracking Gain Adjustment

RV701 : Focus Bias Adjustment