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— 13 —

Procedure:
1. Press  FUNCTION  button to Select VIDEO.
2. Mode: record

blank tape
CS-123

Procedure:
1. Press  FUNCTION  button to Select VIDEO.
2. Mode: record

4. Confirm playback the signal recorded in step 2 become adjustment

level as follows.
If these levels do not adjustment level, adjust the RV341 (L-CH)
and RV441 (R-CH) on the MD board to repeat steps 2 and 3.

Adjustment level: The playback output of 10 kHz level difference

against 315 Hz reference should be ± 0.5 dB.

Adjustment Location: MD board

VIDEO IN
1) 315Hz
2) 10kHz

}

 50 mV (–23.8 dB)

AF OSC

attenuator

600 

blank tape
CS-123

set

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

level meter

recorded
position

set

3. Mode: Playback

Adjustment Location:
[MD BOARD] (Conductor Side)

VIDEO IN
315kHz 50mV (–23.8 dB)

AF OSC

attenuator

600 

set

3. Mode: Playback

recorded
portion

set

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

4. Confirm playback the signal recorded in step 2 become adjustment

level as follows.
If these levels do not adjustment level, adjust the RV301 (L-CH)
and RV351 (R-CH) on the main board to repeat steps 2 and 3.

CN403 PB level: 47.3 to 53.1 mV (–24.3 to –23.3 dB)

Adjustment Location: MAIN board

RV301

IC401

1 3

CN403

RV351

RV351
Record Level Adjustment
(R CH)

RV301
Record Level Adjustment
(L CH)

RV341 (L CH), 441 (R CH)
Record Bias Adjustment

RV301

RV401

RV341

RV651

RV652

RV311

RV411

RV301 (L CH), 401(R CH)
Playback Level Adjustment
(Deck B)

RV441

RV311 (L CH), 411 (R CH)
Playback Level Adjustment
(Deck A)

level meter

RV651 (Normal speed)
RV652 (High speed)
Tape Speed Adjustment

[MAIN BOARD] (Component Side)

— 14 —

0dB=1µV

 As a front-end (FE1) is difficult to repair if faulty, replace it

with new one.

FM Tuned Level adjustment should be performed after this
AM Tuned Level Adjustment.

Setting:
Band: AM or MW

loop antenna
(Supplied accessories)

AM RF SSG

loop antenna

30% amplitude
modulation by
400Hz signal

60cm

AM antenna
terminal (TM1)

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

Modulation: 999 kHz (at 9 kHz step)

1,050 kHz (at 10 kHz step)

Procedure:
1. Supply a 25 dB 98 MHz signal from the ANTENNA terminal.
2. Tune the set to 98 MHz.
3. Adjust RV42 (EXCEPT Thailand model), RV41 (Thailand model)

to the point (moment) when the TUNED indicator will change
from going off to going on.

Adjustment Location: TCB board

set

Procedure:
1. Set the output of SSG so that the input level of the set becomes 55

dB.

2. Tune the set to 999 kHz or 1,050 kHz.
3. Adjust RV41 (EXCEPT Thailand model), RV42 (Thailand model)

to the point (moment) when the TUNED  indicator will change
from going off to going on.

Adjustment Location: TCB board

 This adjustment should be after AM Tuned Level Adjustment.

Setting:
Band: FM

FM RF stereo signal
generator

75  coaxial

set

Carrier frequency: 98MHz
Modulation:

AUDIO 1kHz, 75kHz
deviation (100%)

Output level:

25dB (at 75  open)

Adjustment Location:
EXCEPT  Thailand model
[TCB BOARD] (Component Side)

RV41
AM Tuned Level
Adjustment

RV41

TM1

IC41

RV42

RV42
FM Tuned Level
Adjustment

FE1

Thailand model
[TCB BOARD] (Component Side)

RV41
FM Tuned Level
Adjustment

IC2

RV41

RV42
AM Tuned Level
Adjustment

RV42

TM1

FE1

FM ANTENNA terminal
(TM1)

— 15 —

Setting:
Band: SW

Procedure:
1. Connect digital Voltmeter to diode D1 center lead and ground.
2. Adjust for a following value reading on digital voltmeter.

Procedure:
Adjust for maximum reading on level meter.

[TCB BOARD] — Component Side —

D1, CV2, T2
SW OSC Voltage
Adjustment

IC41

CV2 CV1

D1

T2

T1

TM1

CV1, T1
SW Tracking
Adjustment

• Abbreviation

EA: Saudi Arabia model.
MY: Malaysia model.
SP:

Singapore model.

HK: Hong Kong model.
TW: Taiwan model.
IA:

Indonesian model.

Set frequency

5.95 MHz

17.9 MHz

T2

CV2

1.2 ± 0.1 V

8.5 ± 0.2 V

Adjustment

part

Reading on digital

voltmeter

SW

Setting:
Band: SW

AM RF SSG

set

level meter

SPEAKER terminal

AM ANTENNA terminal

30% amplitude
modulation by
400Hz signal

Set frequency

SW

7 MHz

17 MHz

T1

CV1

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

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

Adjustment

part

— 16 —

1. CD Block is basically designed 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  impedance.
4. Clean the object lens by an applicator with neutral detergent when

the signal level is low than specified value with the following
checks.

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

BD board

TP (RF)

TP (VC)

oscilloscope

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

(Ground terminal : TP (VC))

2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Adjust RV101 so that the waveform is clear.

(Clear RF signal waveform means that the shape “ ” can be clearly
distinguished at the center of the waveform.)

5. After adjustment, check the RF signal level.

• RF signal

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

level: 1.3 ± 0.3 Vp-p

BD board

TP (FE)
TP (VC)

oscilloscope

1. Connect oscilloscope to test point TP (FEO).
2. Connect between test point TP (FOK) and Ground by lead wire.
3. Turn Power switch on.
4. Put disc (YEDS-18) in and turned Power switch on again and

actuate the focus search. (actuate the focus search when disc table
is moving in and out.)

5. Check the oscilloscope waveform (S-curve) is symmetrical

between A and B. And confirm peak to peak level within 2.4 ± 0.7
Vp-p.

S-curve waveform

6. After check, remove the lead wire connected in step 2.

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

A

B

symmetry

within 2.4 ± 0.7 Vp-p

 • Try to measure several times to make sure than the ratio of

A : B or B : A is more than 10 : 7.

• Take sweep time as long as possible and light up the

brightness to obtain best waveform.

BD board

oscilloscope

TP (RF)
TP (VC)

1. Connect oscilloscope to test point TP (RF) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Confirm that oscilloscope waveform is clear and check RF signal

level is correct or not.

Clear RF signal waveform means that the shape “ ” can be
clearly distinguished at the center of the waveform.

RF signal waveform

level: 1.3 ± 0.3 Vp-p