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– 37 –

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.

5.95 MHz

T2

1.2 ± 0.1 V

SW

17.9 MHz

CV2

8.5 ± 0.2 V

Setting:
Band: SW

Procedure:
Adjust for maximum reading on level meter.

•

Repeat the procedures is each adjustment several times, and the
frequency coverage and tracking adjustment should be finally
done by the trimmer capacitors.

7 MHz

T1

SW

17 MHz

CV1

[TCB BOARD]  (Component Side)

RV41

D1, CV2, T2
SW OSC Voltage
Adjustment

CV1, T1
SW Tracking
Adjustment

RV42

IC41

TM1

T2

T1

D1

CV2 CV1

30% amplitude
modulation by
400Hz signal

AM ANTENNA terminal

SPEAKER terminal

set

AM RF SSG

level meter

– 38 –

1. Set the modulation of FM RF SSG to AUDIO 1 kHz, 10 kHz

deviation according to "Connection 1".

2. Tune the set to 69 MHZ.
3. Adjust the RV1702 so that the reading of frequency counter

connected to TP1702 becomes within 31.25 kHz  ± 0.05
kHz.(VCO adjustment)

4. Then record the reading of the level meter connected to TP1701
5. Set the modulation of FM RF SSG to AUDIO 31.25 kHz, 10

kHz deviation according to "Connection 2".

6. Tune the set to 69 MHz.
7. Set the CT1701 to be mechanical center.
8. Adjust the L1701 so that the reading of the level meter con-

nected to TP1701 become maximum.
Then adjust the CT1701 so that the reading of the level meter
connected to TP1701 becomes maximum. (SUB CARRIER
PEAK Adjustment)

9. Adjust the RV1701 so that the level at the moment becomes

14dB higher value than the level recorded in step 4. (SUB CAR-
RIER LEVEL Adjustment)

FM ANTENNA terminal
(75 

Ω

)

75 

Ω

 coaxial

set

FM RF SSG

Carrier frequency : 69 MHz
Output level

: 1mV (60dBµ) (at 75 

Ω

 open)

Modulation

: AUDIO 1 kHZ, 10kHz deviation

FM ANTENNA terminal
(75 

Ω

)

75 

Ω

 coaxial

set

FM RF SSG

AF OSC

Audio 31.25 kHz

external
modulation
terminal

Carrier frequency : 69 MHz
Output level

: 1mV (60 dBµ) (at 75 

Ω

 open)

Modulation

: AUDIO 31.25 kHZ, 10 kHz deviation

(EXTERNAL MODULATION)

• Abbreviation

EE:  East European model

RV41

IC1701

RV42

RV1701

CT1701

TP1702
(VCO)

(FILTER) TP1701

TM1

FE1

+
–

FREQUENCY COUNTER

+
–

LEVEL METER

IC41

L1701

RV1702

RV41
AM tuned level
Adjustment

RV1701, TP1701
Sub carrier level
Adjustment

RV1702, TP1702
VCO Adjustment

RV42
FM tuned level
Adjustment

CT1701, L1701, TP1701
Sub carrier peak
Adjustment

– 39 –

CD SECTION

Note:
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 fol-
lowing checks.

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

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

VC)

2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
4. Confirm that the shape “≈” can be clearly distinguished at the

center of the waveform and check the RF signal level.

Procedure:
1. Connect oscilloscope to test point TP (FEO).
2. Connect between test point TP (FOK) and GND 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 3±1 Vp-p.

S-curve waveform

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

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.

+
–

BD board

TP (FEO)
TP (VC)

oscilloscope

+
–

BD board

TP (RF)

TP (VC)

oscilloscope

(DC range)

A

B

symmetry

within 3 

±

 1 Vp-p

VOLT/DIV: 200 mV
TIME/DIV: 500 ns

level:
1.3 

±

 0.3 Vp-p

VOLT/DIV: 200 mV
TIME/DIV: 500 ns

level:
1.3 

±

 0.3 Vp-p

+
–

BD board

TP (RF)
TP (VC)

oscilloscope

– 40 –

Procedure:
1. Connect oscilloscope to test point TP (TEO) on BD board.
2. Turned Power switch on.
3. Put disc (YEDS-18) in to play the number five track.
4. Press the “

P (Pause)” button.  (Becomes the 1 track jump mode)

5. Check the level B of the oscilloscope's waveform and the A (DC

voltage) of the center of the Traverse waveform.
Confirm the following:

A – B

2 (A + B)  

×

 100 = ±7 (%)

1 track jump waveform

[BD BOARD]  (Conductor Side)

+
–

BD board

TP (TEO)
TP (VC)

oscilloscope

IC103

CNU102

IC101

IC
I02

RF

FOK

VC

FEO

TEO

GND

CNU101

GND

Center of the waveform

B

level : 500 mV 

±

 100 mVp-p

symmetry

A (DC voltage)

0V