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13

This model has the self-diagnosis function for the VIDEO and AUDIO decoder sections.
Immediately after the power on, the self-diagnosis function searches each operation of IC’s around the mechanism control microcomputer
(IC701).
The results can be checked by D502 of the VIDEO board.

• When D502 turns on the IC is normal.
• When D502 flashes twice, the MPEG decoder (IC505) is abnormal.
• When D502 flashes three times, the MPEG decoder (IC505) or

the DRAM (IC507) is abnormal.

D502

IC505

100

91

33

64

90

65

1

32

14

On this mode, the data of the color-bars signal as a picture signal and the 1kHz sine wave signal as a sound signal are output by the
mechanism control microcomputer (IC502) for video CD signal check. When measurement of the voltage and waveform on the VIDEO
board, perform it in this mode.
For refernce, the color-bars signal can be observed at J302 (VIDEO OUT) and the sound signal can be observed at J101 (VIDEO/MD
(AUDIO) OUT) using an oscilloscope.
1.

Connect the lead wire to both ends of the land of SL503 of the VIDEO board.

2.

Turn the power on. Press  FUNCTION  button to select CD.

3.

After 2 or 3 seconds later, connect the lead wire.

4.

After measuring, remove the lead wire connected.

SL501

D502

SL502

IC507

IC505

CT503

SL503

TEST MODE

VIDEO
FREQUENCY

SL501

IC502

SL502

SL503

TEST

MODE

15

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.

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.

test tape
P-4-A100
(10kHz, –10dB)

MD OUT

level meter

set

+

–

L-CH
peak

R-CH
peak

screw
position

output
level

within
1 dB

L-CH
peak

R-CH
peak

screw
position

within 1dB

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

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

71 to 143 g • cm

(0.98 – 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

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 adjusted.

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.

Note: Perform this adjustments for both decks.

Procedure:
1.

Mode : Playback

P-4-A100

WS-48B

P-4-L300

10 kHz, –10 dB

3 kHz, 0 dB

315 Hz, 0 dB

Azimuth Adjustment

Tape Speed Adjustment

Level Adjustment

16

4.

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

Adjustment Location: Playback Head (Deck A)

Record/Playback/Erase Head (Deck B)

3.

Mode: Playback

Note: Set the test mode using the following method and begin tape

speed adjustment.
In the test mode, the speed will switch to double speed or
normal speed each time the  HI-SPEED DUB  button is pressed.

Procedure:
With the power turned ON, press the 

t/CLOCK SET  button,

ENTER  button, and  DISC 3  button simultaneously.
(The “VOLUME” on the fluorescent display tube will blink while
in the test mode.)
To exit the test mode, press the  

1/u  button.

1.

Insert the WS-48B into deck B.

2.

Press the  

·  button of deck B.

3.

Press the  HI-SPEED DUB  button and play the tape at double speed.

4.

Adjust RV1001 of the LEAF SW board so that the reading of
the frequency counter becomes 6000 ± 180 Hz.

5.

Press the  HI-SPEED DUB  button and play the tape at normal speed.

6.

Adjust RV1002 of the LEAF SW board so that the reading of
the frequency counter becomes 3000 ± 90 Hz.

Adjustment Location: LEAF SW board

W.RMS (JIS) less than 0.3%
(test tape: 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 the following adjustment level.

Adjustment level:
CN301 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

test tape
P-4-A100
(10kHz, –10dB)

oscilloscope

set

Waveform of oscilloscope

in phase

45

°

90

°

135

°

180

°

good

wrong

MD OUT

Reverse

Foward

Remove the cassette lid.

test tape 
P-4-L300
(315Hz, 0dB)

level meter

set

MD OUT

RV1002

RV1001

RV1002(Normal Speed)

RV1001(High Speed)