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— 13 —

INTRODUCTION
When set to the test mode performed in 

,

when the tape is rewound after recording, the “REC memory

mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this ad-
justment. During recording, the input signal FUNCTION will auto-
matically switch to VIDEO.

1. Press  FUNCTION  button to select VIDEO. (This step is not

necessary if the above test mode has already been set.)

2. Load a tape into deck B, and press the  

r REC  button.

3. Mode: Record

set

VIDEO (AUDIO) IN
1) 315Hz
2) 10kHz

} 50 mV (–23.8 dB)

AF OSC

attenuator

600 

Ω

blank tape
CS-123

4. Mode: Playback

recorded
position

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

set

level meter

5. Confirm playback the signal recorded in step 2 become adjust-

ment level as follows.
If these levels do not adjustment level, adjust the RV341 (L-
CH) and RV441 (R-CH) on the AUDIO board to repeat steps 3
and 4.

Adjustment level: The playback output of 10 kHz level difference

against 315 Hz reference should be ± 0.5 dB.

Adjustment Location: AUDIO board

RV341(Lch),RV441(Rch)
Record Bias

RV301

RV401

RV441 RV341

RV301(Lch),RV401(Rch)
Playback Level (Deck B)

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

RV652

RV651

RV311

RV411

RV311(Lch),RV411(Rch)
Playback Level (Deck A)

INTRODUCTION
When set to the test mode performed in 

, when the tape is rewound after recording, the “REC memory

mode” which rewinds only the recorded portion and playback is
set.
This “REC memory mode” is convenient for performing this
adjustment. During recording, the input signal FUNCTION will
automatically switch to VIDEO.

1. Press  FUNCTION  button to select VIDEO. (This step is not

necessary if the above test mode has already been set.)

2. Load a tape into deck B, and press the  

r REC  button.

3. Mode: Record

VIDEO (AUDIO) IN
315 Hz 50 mV (–23.8 dB)

set

blank tape
CS-123

600 

Ω

attenuator

AF OSC

4. Mode: Playback

level meter

set

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

recorded
position

5. Confirm playback the signal recorded in step 2 become adjust-

ment 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 3
and 4.

Adjustment level:
CN403 playback level: 47.2 to 53.0 mV (–24.3 to –23.3 dB)

Adjustment Location: MAIN board

Adjustment Location
[AUDIO BOARD] (Conductor Side)

RV301
Record Level (L CH)

IC401

RV351
Record Level
(R CH)

CN403

1

3

[MAIN BOARD] (Component Side)

— 14 —

0dB=1µV

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, East European, CIS models.

Note: FM Tuned Level adjustment should be performed after this

AM Tuned Level Adjustment.

Setting:
Band: MW

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

55 dB or 58 dB. (55 dB : Except East European, CIS model, 58
dB : East European, CIS model)

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

loop antenna

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

AM RF SSG

30% amplitude
modulation by
400Hz signal

60cm

AM antenna
terminal (TM1)

loop antenna
(Supplied accessories)

Modulation: 999 kHz (at 9 kHz step)

1,050 kHz (at 10 kHz step)

set

TM1

IC21

RV41
AM  Tuned Level

RV42

FM Tuned

Level

Adjustment Location
[TCB BOARD] (Component Side)

FM RF SSG

set

FM ANTENNA terminal
(TM1)

75 

Ω

 coaxial

Carrier frequency: 98MHz
Modulation:

AUDIO 1kHz, 75kHz
deviation (100%)

Output level:

25dB (at 75 

Ω

 open)

(EXCEPT East European, CIS model)
23dB (at 75 

Ω

 open)

(East European, CIS model)

Procedure:
1. Supply a 25 dB or 23 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.

Adjustment Location: TCB board

— 15 —

FM  RF SSG

FM antenna
terminal (75 

Ω

)

75 

Ω

 coaxial

set

Carrier frequency: 69 MHz
Output level:

1 mV (60 dBµ) (at 75 

Ω

 open)

Modulation:

AUDIO 1 kHz, 10 kHz deviation

75 

Ω

 coaxial

FM  RF SSG

FM antenna
terminal (75 

Ω

)

AF OSC

Audio 31.25kHz

external
modulation
terminal

Carrier frequency: 69 MHz
Output level:

1 mV (60 dBµ) (at 75 

Ω

 open)

Modulation:

AUDIO 31.25 kHz, 10 kHz deviation
(EXTERNAL MODULATION)

Procedure :
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 con-

nected to TP1702 (VCO) 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 (FILTER) becomes maximum.
Then adjust the CT1701 so that the reading of the level meter
connected to TP1701 (FILTER) becomes maximum. (SUB CAR-
RIER PEAK Adjustment)

9. Adjust the RV1701 so that the level at the moment becomes 14

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

[TCB BOARD] (Conductor Side)

[TCB BOARD] (Component Side)

+

_

frequency counter

level meter

TP1701
(FILTER)

TP1702
(VCO)

IC1701

set

IC1701

RV1702
VCO

RV1701
Sub Carrier
Level

CT1701

L1701

Sub Carrier Peak

— 16 —

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  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.

oscilloscope

BD board

TP (RF)
TP (VC)

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

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

level: 1.3 ± 0.3 Vp-p

oscilloscope

BD board

TP (FEO)
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 be-

tween A and B. And confirm peak to peak level within 3 ± 1Vp-p.

S-curve waveform

within 3 ± 1 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 bright-

ness to obtain best waveform.

symmetry

B

A