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13

On this mode, the data of the color-bars signal as a picture signal
and the 1 kHz sine wave signal as a sound signal are output by the
mechanism controller (IC505) 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-bars signal can be observed at J502 (VIDEO
OUT) and the sound signal can be observed at J101 (VIDEO/MD
(AUDIO) OUT) using an oscilloscope.
Procedure:
1. Short the both ends of the land of SL503 of the VIDEO board.
2. Turn the power on. Press the  FUNCTION  button to select CD.
3. The color-bars appears when the CD is in stop status, and it

disappears when the CD goes in play status.

4. After measuring, remove the lead wire connected.

IC505

CN501

CN502

SL501

SL503

100

81

1

30

31

50

51

80

SL502

14

1. Demagnetize the record/playback head with a head

demagnetizer.

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  the DOLBY NR OFF.
9. Set to the test mode.

(1) Press the

1/

u

button to turn the power ON.

(2) Select the function “TAPE A or B”.
(3) Press the button of

p ,  ENTER/NEXT  , and  DISC3

simultaneously, to set the tape deck test mode and blink
the indicator of disc tray number on the fluorescent indicator
tube.

(4) To exit from the test mode, press the

1/

u

button.

• Test Tape

 Perform this adjustments for both decks

Procedure:
1. Mode: Playback (FWD)

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

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

swab:

record/playback heads

pinch rollers

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.

0 dB = 0.775 V

set

MAIN board
MD OUT jack (J101)
L-CH, R-CH

+
–

level meter

test tape
P-4-A100
(10 kHz, – 10 dB)

31 to 71 g • cm

(0.43 - 0.98 oz • inch)

2 to 6 g • cm

(0.03 - 0.08 oz • inch)

31 to 71 g • cm

(0.43 - 0.98 oz • inch)

2 to 6 g • cm

(0.03 - 0.08 oz • inch)

71 to 143 g • cm

(0.99 - 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

FWD

FWD
back tension

REV

REV
back tension

FF/REW

FWD tension

REV tension

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

15

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 1dB of peak.

3. Mode: Playback

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

pats adjusted.

Adjustment Location: Playback Head (Deck A).

Record/Playback/Erase Head (Deck B).

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

set

test tape
P-4-A100
(10 kHz, – 10 dB)

R-CH

oscilloscope

L-CH

R-CH

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

MAIN board
MD OUT jack (J101)
L-CH

Mode: Playback

1. Insert the WS-48B into the deck B.
2. Press the

( button on the deck B.

3. Press the  HI-DUB  button in playback mode.

Then at HIGH speed mode.

4. Adjust RV1001 on the LEAF SW board do that frequency

counter reads 6,000 ± 180 Hz.

5. Press the  HI-DUB  button.

Then back to NORMAL speed mode.

6. Adjust RV1002 on the LEAF SW board so that frequency

counter reads 3,000 ± 90 Hz.

Adjustment Location: LEAF SW board
Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

(WS-48B)

Procedure:
Mode: Playback

Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301
(L-CH) and RV401 (R-CH) so that adjustment within specification
values as follows.

J101 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

forward

reverse

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

MAIN board
MD OUT jack (J101)
L-CH, R-CH

frequency counter

+
–

set

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

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level meter

16

Procedure:
1. Mode: Record

FUNCTION: VIDEO

2. Mode: Playback

3. Confirm playback the signal recorded in step 1 become

specification values as follows.
If these values are out of specification values, adjust the RV341
(L-CH) and RV441 (R-CH) on the AUDIO board to repeat steps
1and 2.

Specification values: Playback output of 315 Hz to playback

output of 10 kHz: ± 0.5 dB

Adjustment Location: AUDIO board

Procedure:
1. Mode: Record

FUNCTION: VIDEO

2. Mode: Playback

3. Confirm playback the signal recorded in step 1 become

specification values as follows.
If these values are out of specification values, adjust the RV301
(L-CH) and RV351 (R-CH) on the MAIN board to repeat steps
1 and 2.

Specification values:
J101 PB level:  47.2 to 53.0 mV (- 24.3 to - 23.3 dB)

Adjustment Location: MAIN board

attenuator

set

MAIN board 
VIDEO (AUDIO) IN jack (J101)
L-CH, R-CH

1) 315 Hz
2) 10 kHz

50 mV (– 23.8 dB)







600 

Ω

blank tape
CN-123

AF OSC

+
–

set

recorded
portion

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level meter

set

MAIN board
VIDEO (AUDIO) IN jack (J101)
L-CH, R-CH
315 Hz, 50 mV (– 23.8 dB)

blank tape
CS-123

600 

Ω

attenuator

AF OSC

+
–

set

recorded
portion

MAIN board
MD OUT jack (J101)
L-CH, R-CH

level meter

RV301

L

RV351

R

IC301

REC LEVEL

J101

VIDEO (AUDIO) IN

(L/R)

MD OUT

(L/R)

RV401

RV301

RV341

RV311

RV411

IC602

CN601

L

R

R L





 





 

RV441

PB LEVEL

– DECK B –

REC BIAS

L

R





 

PB LEVEL

– DECK A –

TAPE SPEED

RV1002

RV1001

(NORMAL)  (HIGH)

CN1001



















