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— 10 —

2. Turn the adjustment screw and check output peaks. If the peaks

do not match for L-CH and R-CH, turn the adjustment screw so
that outputs match within 1 dB of peak.

output
level

3. Mode: Playback

Note: Start the Tape Speed adjustment as below after setting the test

mode.
The tape speed can be changed with the  HIGH SPEED
DUBBING   button during the test mode.

Method :
1. Turn the power switch on.
2. Press the  DISPLAY/DEMO  button,  FILE 1  button and    TUNER/

BAND   button simultaneously.

To exit from the test mode, Press the  SYSTEM POWER  button.

Procedure :
Mode: Playback

4. After the adjustments, apply suitable locking compound to the

parts adjusted.

Adjustment Location: Playback Head (Deck A)

Record/Playback/Erase Head (Deck B)

45˚

90˚

135˚

180˚

wrong

good

in phase

R

set

FWD side

REV side

L-CH
peak

screw
position

R-CH
peak

within
1dB

within 1dB

L-CH
peak

R-CH
peak

screw
position

test tape
P-4-A100
(10kHz, –10dB)

main board
CN403
Pin 

3

 (L-CH)

oscilloscope

Pin 

2

 (GND)

L

Pin 

1

 (R-CH)

Waveform of oscilloscope

Adjustment screw

+
–

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

set

test tape WS-48B
(3kHz, 0dB)

frequency counter

1. Insert the WS-48B into the deck A to playback.
2. Press the  HIGH SPEED DUBBING  button. Then at HIGH

SPEED mode.

3. Adjust the RV652 on the AUDIO board so that the frequency

counter reading becomes 6,000 ± 30 Hz.

4. Press the  HIGH SPEED DUBBING  button again to be set the

NORMAL SPEED mode.

5. Set to the playback mode.
6. Adjust the RV651 on the AUDIO board so that the frequency

counter reading becomes 3,000 ± 15 Hz.

Frequency difference between deck A and deck B the beginning
of the tape should be within ± 1.5%.

Adjustment Location: AUDIO board

Procedure:
Mode: Playback

set

test tape P-4-L300
(315Hz, 0dB)

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

level meter

Deck A is RV311 (L-CH) and RV411 (R-CH), deck B is RV301
(L-CH) and RV401 (R-CH)
so that adjustment within the following adjustment level.

Adjustment level:
CN403 playback level: 301.5 to 338.3 mV (–8.2 to –7.2 dB)
level difference between the channels: within ± 0.5 dB
Adjustment Location: AUDIO board

— 11 —

Reference)
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 stops is set.
This “REC memory mode” is convenient for performing this adjust-
ment.

1. Press  FUNCTION  button to select VIDEO.
2. Mode: record

Reference)
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 stops is set.
This “REC memory mode” is convenient for performing this
adjustment.

1. Press  FUNCTION  button to select VIDEO.
2. Mode: record

set

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

} 50 mV (–23.8 dB)

AF OSC

attenuator

600 

Ω

blank tape
CS-123

3. Mode: Playback

4. 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 2 and 3.

Adjustment level: The playback output of 10 kHz level difference

against 315 Hz reference should be ± 0.5 dB.

Adjustment Location: AUDIO board

recorded
position

level meter

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

set

blank tape
CS-123

600 

Ω

attenuator

AF OSC

3. Mode: Playback

level meter

set

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

recorded
position

4. 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 2 and 3.

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

Adjustment Location: MAIN board

Adjustment Location
[AUDIO BOARD] (Conductor Side)

[MAIN BOARD] (Component Side)

main board
CN403 Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

set

1  3

CN403

RV351

IC401

RV301

RV351
Record Level Adjustment
(R CH)

RV301
Record Level Adjustment
(L CH)

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)

— 12 —

0dB=1µV

Note: 1. 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: MW

loop antenna

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

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 RV42 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

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

75 

Ω

 coaxial

set

Carrier frequency: 98MHz
Modulation:

AUDIO 1kHz, 75kHz
deviation (100%)

Output level:

25dB (at 75 

Ω

 open)

FM RF SSG

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 RV41 to the point (moment) when the TUNED indicator

will change from going off to going on.

Adjustment Location
[TCB BOARD] (Component Side)

RV42

AM Tuned

Level

TM1

FE1

RV41
FM  Tuned Level

IC2

— 13 —

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.

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)

level: 1.3 ± 0.3 Vp-p

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

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.

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 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

VOLT/DIV: 200 mV
TIME/DIV: 500 nS

A

B

within 2.4 ± 0.7 Vp-p

symmetry

oscilloscope

BD board

oscilloscope

BD board

TP (RF)
TP (VC)

TP (FEO)
TP (VC)