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— 17 —

A = 0.9 to 1.1 Vp-p
B = 0.678 to 0.75 Vp-p
C = 0.214 to 0.328 Vp-p

[VIDEO BOARD] (SIDE-B)

+
–

oscilloscope

75 

Ω

set

J9001 (VIDEO OUT)

B

H

C

A

SL702

SL701

IC751

SL703

IC251

Refer to the SECTION 6 ELECTRICAL ADJUSTMENTS page
21.
Procedure:
1. Turned power switch on.
2. Press the  FUNCTION  button to select the CD.
3. Connect the SL701 and SL703 on the VIDEO board with solder.
4. Press the  

· button in playback.

5. Press the  REPEAT  button, the tracking servo and sledding

servo are turned on or off.

6. When the servo is off, the counter on front panel will not be

changed.

7. After measuring, remove the soldering installed.

On this mode, the data of the color bar signal as a picture signal and
the 1 kHz sine wave signal as a sound signal are output by the
mechanism controller (IC701) for the video CD signal check.  When
measurement of the voltage and waveform on the VIDEO board,
perform it in this mode.
For reference, the color bar signal can be observed at J9001 (VIDEO
OUT) and the sound signal can be observed at J101 (VIDEO
(AUDIO) OUT) using an oscilloscope.
Procedure:
1. Turned power switch on.
2. Press the  FUNCTION  button to select the CD.
3. Connect the SL701 on the VIDEO board with solder.
4. After measuring, remove the soldering installed.

— 18 —

1.

Demagnetize the record/playback head with a head
demagnetizer.  (Do not bring the head demagnetizer close to
the erase head.)

2.

Do not use a magnetized screwdriver for the adjustments.

3.

After the adjustments, apply suitable locking compound to the
parts adjust.

4.

The adjustments should be performed with the rated power
supply voltage unless otherwise noted.

5.

The adjustments should be performed in the order given in this
service manual.  (As a general rule, playback circuit adjustment
should be completed before performing recording circuit
adjustment.)

6.

The adjustments should be performed for both L-CH and R-
ch.

7.

Switches and controls should be set as follows unless otherwise
specified.

8.

Set to test mode.  (Press key switch same time

GROOVE   ENTER/NEXT and  DISC 4 buttons.)

To exit from the test mode, press the

1/u button.

•

Test Tape

1. Clean the following parts with a denatured-alcohol-moistened

swab:

record/playback head pinch roller
erase head

rubber belts

capstan

idlers

2. Demagnetize the record/playback head with a head

demagnetizer.

3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the

parts adjusted.

5. The adjustments should be performed with the rated power

supply voltage unless otherwise noted.

• Torque Measurement

Mode

Torque Meter

Meter Reading

Forward

CQ-102C

36 to 61g•cm

(0.50 – 0.84 oz•inch)

Forward

CQ-102C

2 to 6g•cm

Back Tension

(0.026 – 0.082 oz•inch)

Reverse

CQ-102RC

36 to 61g•cm

(0.50 – 0.84 oz•inch)

Reverse

CQ-102RC

2 to 6g•cm

Back Tension

(0.026 – 0.082 oz•inch)

FF, REW

CQ-201B

61 to 143g•cm

(0.85 – 1.98 oz•inch)

Mode

Tension Meter

Meter Reading

Forward

CQ-403A

more than 100 g (3.53 oz)

Reverse

CQ-403R

more than 100 g (3.53 oz)

0 dB=0.775 V

Tape

Signal

Used for

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0 dB

Tape Speed Adjustment

P-4-L300

315 Hz, 0 dB

Level Adjustment

• Tape Tension  Measurement

Note:

  Perform this adjustments for both decks.

Procedure:
1. Mode:  Playback (FWD)

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.

set

MAIN board
CN207
pin 

3

 (L-CH)

pin 

1

 (R-CH)

MAIN board
CN207
pin 

2

 (GND)

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

Screw
position

L-CH
peak

within
1 dB

output
level

L-CH
peak

R-CH
peak

within
1 dB

Screw
position

R-CH
peak

— 19 —

3. Mode:  Playback (FWD)

4. Repeat steps 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the

parts adjusted.

Adjustment Location : Playback Head (Deck A)

Record/Playback Head (Deck B)

Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within adjustment
level as follows.
Adjustment Level:

CN207 PB 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 (See page 20)

set

test tape
P-4-A100
(10 kHz, –10 dB)

pin 

1

 (R-CH)

oscilloscope

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

pin 

2

 (GND)

pin 

3

 (L-CH)

MAIN board
CN207

reverse

forward

Note:

Start the Tape Speed adjustment as below after setting to the test

mode.
In the test mode, the tape speed is high during press the
 H SPEED DUB button.

Procedure:
1. Turn the power switch on.
2. Press the GROOVE button, ENTER/NEXT button and

  DISC 4  button simultaneously.
To exit from the test mode, press the

1/u button.

Mode:  Playback (FWD)

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

MAIN board
CN207 (pin 

3

 : L-CH)

     (pin 

1

 :R-CH)

frequency counter

+
–

set

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

MAIN board
CN207 (pin 

3

: L-CH)

(pin 

1

: R-CH)

level meter

1. Insert the WS-48B into the deck A and the blank tape into the

deck B.

2. Press the

r REC button and · button on the deck B.  Then

the deck B is at recording mode.

3. Set the deck A to playback mode.
4. Press the H SPEED DUB button in playback mode.

Then at high speed mode.

5. Adjust RV652 on the AUDIO board so that frequency counter

reads 6,000 ± 180 Hz.

6. Press the H SPEED DUB button.

Then at normal speed mode.

7. Adjust RV651 on the AUDIO  board so that frequency counter

reads 3,000 ± 90 Hz.

8. Frequency difference between deck A and deck B the beginning

of the tape should be within ± 1.5 %.

Adjustment Location:  AUDIO board (See page 20)

Sample Value of Wow and Flutter:   0.3% or less W.RMS

        (WS-48B)

Procedure:
Mode:  Playback (FWD)

— 20 —

2. Mode:  Playback

Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV341 (L-
CH) and RV441 (R-CH) on the AUDIO board to repeat steps 1 and
2.
Adjustable limits:

Playback output of 315 Hz to playback
output of 10 kHz:  ±0.5 dB

Adjustment Location: AUDIO board

Procedure:
1. Mode:  Record

2.

Mode:  Playback

Confirm playback the signal recorded in step 1 become adjustable
limits as follows.
If these levels do not adjustable limits, adjustment the RV1501 (L-
CH) and RV1551 (R-CH) on the MAIN board to repeat steps 1 and
2.
Adjustable limits:

CN207 PB level:  47.3 to 53.1 mV (–24.3 to –23.3 dB)

Adjustment Location:  MAIN board

[MAIN  BOARD] (Component Side)

Adjustment and Connection Location:

[AUDIO  BOARD]  (Conductor Side)

Procedure:
1. Mode:  Record

attenuator

set

pin 

6

 (L-CH) of IC1501 on the MAIN board.

pin 

#¶

 (R-CH) of IC1501 on the MAIN board.

1) 315 Hz
2) 10 kHz

50 mV (–23.8 dB)







pin 

2

 (GND) of CN207 on the MAIN board.

600 

Ω

blank tape
CS-123

AF OSC

+
–

set

recorded
portion

MAIN board
CN207 (pin 

3

: L-CH)

(pin 

1

: R-CH)

level meter

+
–

set

recorded
portion

MAIN board
CN207 (pin 

3

: L-CH)

(pin 

1

: R-CH)

level meter

set

pin 

6

  (L-CH) of IC1501 on the MAIN board.

pin 

#¶

  (R-CH) of IC1501 on the MAIN board.

315 Hz, 50 mV (–23.8 dB)

blank tape
CS-123

pin 

2

  (GND) of CN207 on the MAIN board.

600 

Ω

attenuator

AF OSC

RECORD

BAIS

TAPE SPEED

(NORMAL)

RV651

®

(HIGH)

RV652

®

RV311

L 

®

RV411

R 

®

PB

LEVEL

RV441 RV341

RV301

®

L

RV401

®

R

R

L

– DECK B –

– DECK A –











PB LEVEL

    

































RV1501

IC1501

CN205

CN207

RV1551

RECORD LEVEL

IC301

IC201

1

21

1

22

42

3