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— 11 —

0 dB=1µV

Procedure:
1. Set the reception frequency of the unit to 530 kHz.
2. Adjust L105 for 1.2 ± 0.05 V reading on the DC voltmeter.
3. Set the reception frequency of the unit to 1,710 kHz.
4. Confirm that the voltage reading on the DC voltmeter is within

8.0 ± 0.5 V.

Adjustment Location:  MAIN board

Procedure:
1. Tune the set to 600 kHz.
2. Set the output of AM RF SSG so that the input level of the set

will become 60 dB (µV/m).

3. Adjust L104 so that when the waveform on the oscilloscope is

maximum, no noise appears.

4. Tune the set to 1,400 kHz.

5. Adjust TC102 so that when the waveform on the oscilloscope is

maximum, no noise appears.

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

tracking adjustment should be finally done by the trimmer
capacitors.

Adjustment Location: MAIN board

DC voltmeter

+

–

Procedure :
1. Set the reception frequency of the unit to 87.5 MHz.
2. Adjust L103 for 1.2 ± 0.05V reading on the DC voltmeter.
3. Set the reception frequency of the unit to 108 MHz.
4. Confirm that the voltage reading on the DC voltmeter is within

7.8 ± 0.5V.

Adjustment Location: MAIN board

+

–

DC voltmeter

TP1

Main board

IF
G
VT

set

loop antenna

AM RF SSG

60cm

Field strength dB (µV/m) = SSG output level dB (µV/m) –26dB.

30% amplitude
modulation by
400Hz signal

Center of
Bar antenna (L104)

TP1

Main board

IF
G
VT

— 12 —

Carrier frequency : 98 MHz
Modulation

: AUDIO 1 kHz, 75 kHz

deviation (100%)

Output level

: 28 dB  (at 75 

Ω

 open)

FM RF SSG

set

75 

Ω

 coaxial

FM ANTENNA terminal
(JK101)

Procedure:
1. Supply a 28 dB 98 MHz signal from the ANTENNA terminal.
2. Tune the set to 98 MHz.
3. Adjust SFR101 to the point (moment) when the TUNED indica-

tor will change from going off to going on.

Adjustment Location: MAIN board

FM RF SSG

oscilloscope

FM ANTENNA terminal (JK101)

SPEAKER terminal (JK302)

set

Carrier frequency : 90 MHz, 106 MHz
Modulation

: AUDIO 1kHz, 75kHz deviation (100%)

Output level

: 20 dB (at 75 

Ω

 open)

+

–

1. Tune the set to 90 MHz.
2. Adjust L102 so that when the waveform on the oscilloscope is

maximum, no noise appears.

3. Tune the set to 106 MHz.
4. Adjust TC101 so that when the waveform on the oscilloscope is

maximum, no noise appears.

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

tracking adjustment should be finally done by the trimmer
capacitors.

Adjustment Location: MAIN board

FM Tuning Voltage

JK101

FM Tracking

AM Tuning Voltage

SFR101

FM Tuned Level

AM Tracking

TC101

TC102

L105

L104

L103

L102

IC103

JK302

IC102

TP1

IF

GND

VT

— 13 —

1. CD Block is basically constructed to operate without adjustment.

Therefore, check each item in order given.

2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M

Ω

 impedance.

4. Clean the object lens by an applicator with neutral detergent

when the signal level is low than specified value with the fol-
lowing checks.

5. Adjust the focus bias adjustment when optical block is replaced.

Procedure :
1. Connect oscilloscope to test point TP (RF) on CD DECODER

board.

2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Confirm that oscilloscope waveform is clear and check RF sig-

nal level is correct or not.

Note: Clear RF signal waveform means that the shape “

◊

” can be

clearly distinguished at the center of the waveform.

TP (RF)
CN12 (VC)

CD DECODER
board

oscilloscope

level: 1.0         Vp-p

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

+0.3
–0.2

Adjustment Location: CD DECODER board

FEO

VC

–

+

Procedure:
1. Connect DC voltmeter to test point CN12 (FEO), (VC) on CD

DECODER board.

2. Turned Power switch on.
3. Put disc (YEDS-18) in and stop.
4. Adjust VR01 so that the DC voitmeter reading is 0 ± 20 mV.

Adjustment Location: CD DECODER board

CD DECODER
board

CN12

DC voltmeter

R07

VR01

Focus Bias

Focus Gain

VR02

This gain has a margin, so even if it is slightly off.
There is no problem.
Therfore, do not perform this adjusment.
Please note that it should be fixed to mechanical center position
when you moved and do not know original position.

CN12

IC03

RF Level

IC01

FEO

VC

— 14 —

MAIN Board

DISC board

PANEL board

H/P board

SENSOR board

POWER TRANSFORMER board

SW (B) board

SW (C) board

MOTOR board

SW (D) board

SW (A) board

CD DECODER board

MOTOR (6P) (S) board

R/P SW board