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— 13 —

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 1050 kHz .
3. Adjust RV41 (EA model), RV42 (other model) to the point

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

Adjustment Location : TCB board

Note : This adjustment should be performed after the AM Tuned

Level Adjustement.

Setting :
Band : FM

(Component Side)

loop antenna
(Supplied accessories)

AM RF SSG

30% amplitude
modulation by
400 Hz signal

AM antenna
terminal (TM1)

60 cm

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

Carrier frequency : 999kHz (at 9kHz step)

1050kHz (at 10 kHz step)

• Abbreviation

EA

: Saudi Arabia model

75  coaxial

Carrier frequency : 98MHz
Modulation

: AUDIO 1kHz, 75kHz
  deviation (100%)

Output level

: 25dB (at 75  open)

set

FM ANTENNA terminal
(TM1) (75 )

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

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

Adjustment Location : TCB board

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

with new one.

Note : FM Tuned Level adjustment should be performed after this

AM Tuned Level adjustment.

Setting :
Band : AM or MW

loop antenna

RV41

IC41

RV42

RV42
FM Tuned Level

FE1

TM1

RV41
FM Tuned Level

IC2

RV41

RV42
AM Tuned Level

FE1

TM1

RV41
AM Tuned Level

RV42

FM RF SSG

Other model
[TCB BOARD] (Component Side)

— 14 —

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.

Setting:
Band: SW

Procedure:
Adjust for maximum reading on level meter.

SW

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

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

[TCB BOARD] — Component Side —

• Abbreviation

EA

: Saudi Arabia model

set

SPEAKER terminal

CV2

CV1

T2

T1

CV1, T1
SW Tracking
Adjustment

level meter

AM RF SSG

30% amplitude
modulation by
400Hz signal

AM ANTENNA terminal

TM1

RV41

RV42

D1, CV2, T2
SW OSC Voltage
Adjustment

D1

IC41

Adjustment

part

Reading on digital

voltmeter

SW

5.95 MHz

17.9 MHz

T2

CV2

1.2 ± 0.1 V

8.5 ± 0.2 V

7 MHz

17 MHz

T1

CV1

Set frequency

Set frequency

Adjustment

part

— 15 —

oscilloscope
(DC range)

BD board

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

BD board

TP(FEO)
TP(VC)

oscilloscope

Symmetry

within 2.4 ± 0.7 Vp-p

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

• 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

TP(RF)
TP(VC)

oscilloscope

Procedure :
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 osilloscope 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

VOLT/DIV : 200mV
TIME/DIV : 500nS

level : 1.3 ± 0.3 Vp-p

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 applicatior 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.

TP(RF)

TP(VC)

Procedure :
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

level
1.3 ± 0.3 Vp-p

A

B

— 16 —

BD board

TP (TEO)

TP (VC)

oscilloscope

Procedure :
1. Connect test point TP703 (ADJ 2) on Main board to Ground with

a lead wire.

2. Connect oscilloscope to test point TP (TEO).
3. Turned Power switch on.
4. Put disc (YEDS-18) in and playback.
5. Confirm that the oscilloscope waveform is symmetrical on the

top and bottom in relation to 0Vdc, and check this level.

Traverse waveform

0V

level : 300 ± 100 mVp-p

Specified level : • 

             X

 100=less than ± 7%

• A+B=300 ± 100 mVp-p

6. Remove the lead wire connected in step 1.

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

A-B

2(A+B)

[BD BOARD] (Conductor Side)

[MAIN BOARD] (Conductor Side)

RF

FOK

RV101

RV103

IC101

IC102

TEI

FEI

TEO

RV102

VC

IC104

GND

PCK

IC701

B

A

FEO

TP703
(ADJ 2)