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— 13 —

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

No adjustment is needed due to a tuner pack for except
AEP, UK, German, East European models.

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

Setting:
Band: AM or MW

75 

Ω

 coaxial

set

Carrier frequency: 98MHz
Modulation:

AUDIO 1kHz, 75kHz
deviation (100%)

Output level:

25dB (at 75

Ω

 open)

loop antenna

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

30% amplitude
modulation by
400Hz signal

AM antenna
terminal (TM1)

AM RF SSG

loop antenna
(Supplied accessories)

set

60cm

Modulation: 999 kHz (at 9 kHz step)

1,050 kHz (at 10 kHz step)

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 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 Adjustment.

Setting:
Band: FM

FM ANTENNA terminal
(TM1)

Procedure:
1. Supply a 25 dB 98 MHz signal from the ANTENNA terminal.
2. Tune the set to 98 MHz.
3. Adjust RV42 to the point (moment) when the TUNED indicator

will change from going off to going on.

[TCB BOARD] (Component Side)

TM1

RV41
AM Tuned Level

IC41

RV42
FM Tuned Level

FE1

FM RF SSG

— 14 —

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

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

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).
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

oscilloscope

BD board

TP (RF)
TP (VC)

BD board

oscilloscope

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 be-

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

S-curve waveform

TP (FEO)
TP (VC)

A

B

within 2.4 ± 0.7 Vp-p

symmetry

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 bright-

ness 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 oscilloscope waveform is clear and check RF sig-

nal 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

level: 1.3 ± 0.3 Vp-p

— 15 —

BD board

oscilloscope

TP (TEO)
TP (VC)

Procedure:
1. Connect test point TP703 (ADJ2) on Main board to Ground with

a lead wire.

2. Connect oscilloscpe 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

A

B

level: 300 ± 100 mVp-p

0V

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] — Component Side —

[MAIN BOARD] — Conductor Side —

IC701

TP703

(ADJ2)

IC104

GND

PCK

RF

RV101

IC101

FOK

RV102

TEO

FEO

TEI

FEI

VC

RV103

IC102

— 16 —

PANEL board

MAIN board

SENSOR board

CONNECTOR board

MOTOR (TURN) board

BD board

MOTOR (SLIDE) board

HP board

CD SW board

TRANSFORMER board

TCB board (RX30: AEP, UK, German, East European)
ENCAPSULATED COMPONENT (GR3/RX30: US, Canadian)