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16

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 (IC502) 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 CN301 pin
2

  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  CD  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.VIDEO board

(SIDE B)

Procedure:
1.

Short SL502 on the VIDEO board by soldering.

2.

Turn on the main power.  Set a disc on the DISC1 tray.  Select
CD.

3.

Press the hH button to play back CD.

4.

When the  > +  button is pressed, 100 track jump is executed.

5.

Also, every pressing of the PLAY MODE button triggers
between  ON and OFF of TRACKING SERVO and SLED
SERVO.

How to quit the CD servo ON/OFF mode:
1.

Press the  ?/1  button to turn off the main power.

2.

Remove soldering from SL502.

17

0 dB=0.775 V

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.

• Test Tape

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0 dB

Tape Speed Adjustment

P-4-L300J

315 Hz, 0 dB

Level Adjustment

  Perform this adjustments for both decks

Procedure:
1. Mode:  Playback

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.

set

main board
CN301
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

main board
CN301
Pin 

2

 (GND)

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

3.06 N • m to 6.96 N • m

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

0.19 N • m to 0.58 N • m

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

3.06 N • m to 6.96 N • m

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

0.19 N • m to 0.58 N • m

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

6.96 N • m to 14.02 N • m

71 to 143 g • cm

(0.98 – 1.99 oz • inch)

9.80 N • m

100 g or more

(3.53 oz or more)

9.80 N • m

100 g or more

(3.53 oz or more)

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

FWD

FWD

back tension

REV

REV

back tension

FF/REW

FWD tension

REV tension

18

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. After the adjustments, apply suitable locking compound to the

pats adjusted.

Adjustment Location: Playback Head (Deck A).

Record/Playback/Erase Head (Deck B).

Start the Tape Speed adjustment as below after setting to the test
mode.
In the test mode, the tape speed is high during pressing the

 CD SYNC/HI-DUB 

 button.

Procedure:
1. Turn the power switch on.
2. Press the x button,  ENTER  button and  DISC 3  button

simultaneously.
(The “TEST MODE” on the fluorescent indicator tube display
while in the test mode.)
To exit from the test mode, press the ?/1 button.

Mode:  Playback

1. Insert the WS-48B into the deck B.
2. Press the gG button on the deck B.
3. Press the  CD SYNC/HI-DUB  button in playback mode.

Then at HIGH speed mode.

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

counter reads 6,000 

±

 30 Hz.

5. Press the  CD SYNC/HI-DUB  button.

Then back to NORMAL speed mode.

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

counter reads 3,000 

±

 15 Hz.

Adjustment Location:  LEAF SW board

Procedure:
Mode:  Playback

1. Confirm that level difference between the channels is with 

±

0.5 dB.

2. After check, adjust the following RVs.

Deck A is RV302 (L-CH), Deck B is RV303 (L-CH) so that
adjustment within adjustment level as follows.

CN301 PB level:  334.4 to 748.7 mV (–7.3 to  –0.3 dB)

Adjustment Location:  MAIN board

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

(WS-48B)

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

MAIN
board
CN301
set

test tape
P-4-A100
(10 kHz, –10 dB)

pin 

1

oscilloscope

L-CH

R-CH

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

pin 

2

pin 

3

L

R

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

main board
CN301 (Pin 

3

 : L-CH)

(Pin 

1

 : R-CH)

frequency counter

+
–

set

test tape
P-4-L300J
(315 Hz, 0 dB)

main board
CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

forward

reverse

19

4. Mode:  Record

5. Mode:  Playback

6. Confirm the play back signal recorded in step 3 becomes

adjustable level as follows.
If these levels are not adjustable level, adjust the RV301 (L-
CH) and RV351 (R-CH) on the MAIN board to repeat steps 4
and 5.

Adjustable level:
CN301 PB level:  47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location:  MAIN board

[MAIN  BOARD] (Component Side)

[LEAF  SW  BOARD]  (Component Side)

Procedure:
In the MC test mode, the “REC memory mode” is convenient for
this adjustment. In the “REC memory mode” , when the REC starts
the input signal FUNCTION is switched to VIDEO automatically.
When the REC stops, the tape returns near to the recording start
position.

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

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

2. Insert a tape into deck B.
3. After press  REC PAUSE/START  button, press REC PAUSE/

START button, then recording start.

4. Mode:  Record

5. Mode:  Playback

6. Confirm the playback signal recorded in step 3 becomes

adjustable level as follows.
If these levels are not adjustable level, adjust the RV304 (L-
CH) and RV354 (R-CH) on the MAIN  board to repeat steps 4
and 5.

Adjustable level: Playback output of 315 Hz to playback output

of 10 kHz:  

±

1.0 dB

Adjustment Location:  MAIN board

Procedure:
In the MC test mode, the “REC memory mode” is convenient for
this adjustment. In the “REC memory mode” , when the REC starts
the input signal FUNCTION is switched to VIDEO automatically.
When the REC stops, the tape returns near to the recording start
position.

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

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

2. Insert a tape into deck B.
3. After press  REC PAUSE/START  button, press REC PAUSE/

START button, then recording start.

attenuator

set

MD/VIDEO (AUDIO) IN (J101)

1) 315 Hz
2) 10 kHz

50 mV (–23.8 dB)







600 

Ω

blank tape
CN-123

AF OSC

+
–

set

recorded
portion

CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

set

MD/VIDEO (AUDIO) IN (J101) 
315 Hz, 50 mV (–23.8 dB)

blank tape
CS-123

600 

Ω

attenuator

AF OSC

+
–

set

recorded
portion

CN301 (Pin 

3

: L-CH)

(Pin 

1

: R-CH)

level meter

TAPE SPEED

RV1002

RV1001

(NORMAL)  (HIGH)

CN1001





















T11

RV11

CN301

RV301

RV302

RV303

RV351

RV304

RV354

NO303

CN304

3 1

REC LEVEL (L)

(B)

PB LEVEL (L)

(A)

PB LEVEL (L)

(B)

REC LEVEL (R)

(B)

REC BIAS (R)

(B)

REC BIAS (L)

(B)