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13

Procedure:
1. Extract an AC plug.
2. While depressing the  TAPE N  button, insert an AC plug.
3. The message “TC TEST” is displayed and TC test mode is

activated.

*

Zero Return

1. Press the  M >  or  .m  button.
2. The tape is rewound to the counter zero position.
*

Automatic record/playback test

1. Press  the  REC START/REC PAUSE  button.
2. The message “AUX” is displayed and AUX input is selected.
3. The tape is rewound to the counter zero position and recording

is started automatically.

4. When the  CLEAR x  button  is pressed, the tape is rewound

to the recording stated point and the set starts playback.

5. To exit from this mode, press the  POWER  button or disconnect

the power cord.

•

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 demagne-

tizer.

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.

2.94 mN • m to 7.84 mN • m

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

0.14 mN • m to 0.59 mN • m

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

6.86 mN • m to 17.64 mN • m

71 to 143 g • cm

(0.98 – 1.99 oz • inch)

more than 0.98 N • m

100 g or more

(3.53 oz or more)

CQ-102C

CQ-102C

CQ-201B

CQ-403A

FWD

FWD
back tension

FF/REW

FWD tension

14

1. Demagnetize the record/playback head with a head demagne-

tizer.

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 ad-
justment 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 other-

wise specified.

• Test Tape

Tape

Signal

Used for

P-4-A100

10 kHz, – 10 dB

Azimuth Adjustment

WS-48B

3 kHz, 0 dB

Tape Speed Check

0 dB = 0.775 V

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

parts adjusted.

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
SPEAKER terminal (J302)
L-CH

Procedure:
1. Mode: Playback

set

MAIN board
SPEAKER terminal (J302)
L-CH, R-CH

+
–

level meter

test tape
P-4-A100
(10 kHz, – 10 dB)

15

Mode: Playback

1. Insert the WS-48B into the deck.
2. Press the N button on the deck.
3. Confirm that the frequency counter reads 3,000 

±

 90 Hz.

Sample value of Wow and Flutter: 0.3% or less W.RMS (JIS)

(WS-48B)

+
–

set

test tape
WS-48B 
(3 kHz, 0 dB)

MAIN board
SPEAKER terminal (J302)
L-CH, R-CH

frequency counter

Adjustment Location: Record/Playback/Erase Head

Note: Refer to “3-6. Cassette Door Assy” (see page 10)

adjustment screw

1. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
2. Use an oscilloscope with more than 10M

Ω

 impedance.

3. Clean the object lens by an applicator with neutral detergent when the

signal level is low than specified value with the following checks.

Procedure:
1.

Connect an oscilloscope to test point TP6 (RFDC) and TP7 (VC)
on the BD board.

2.

Turn the power on.

3.

Put the disc (YEDS-18) in to playback the number five track.

4.

Confirm that oscilloscope waveform is clear and check RFDC
signal level is correct or not.

A clear RFDC signal waveform means that the shape “

◊

” can be

clearly distinguished at the center of the waveform.

+
–

BD board

TP6 (RFDC)

TP7 (VC)

oscilloscope

Procedure:
1.

Connect an oscilloscope to test point TP4 (FE) and TP7 (VC)
on the BD board.

2.

While depressing the  CD         button, insert an AC plug.

3.

Put the disc (YEDS-18) in and press the       button and
actuate the focus search. (actuate the focus search when disc
table is moving in and out)

4.

Check the oscilloscope waveform (S-curve) is symmetrical
between A and B. And confirm peak to peak level within 2 

±

 1

Vp-p.

S-curve waveform

• 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

brightness to obtain best waveform.

Checking Location: BD board (Side B)(See page 25)

+
–

BD board

TP4 (FE)

TP7 (VC)

oscilloscope

A

B

symmetry

within 2 

±

 1 Vp-p

u

x

16

Checking Location: BD board (Side B)

Traverse Waveform

0V

B

level: 1.0 

±

 0.5 Vp-p

Center of 
the waveform

A (DC 

voltage)

Traverse Waveform

0V

Tracking servo

Sled servo

ON

C (DC 
voltage)

Tracking servo

Sled servo

OFF

6.

Press the CD 

u

   button. (The tracking servo and sledding

servo are turned ON)
Rotate RV101 on BD board and adjust the C (DC voltage) 
is almost equal to the A (DC voltage) in step 4. 

7. To exit from this mode, turn the power off.

• Always move the optical pick-up to most inside track when

exiting from this mode. Otherwise, a disc will not be unloaded.

• Do not run the sled motor excessively, otherwise the gear can

be chipped.

5.

Check the level B of the oscilliscope's waveform and the A
(DC voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than 

±

 10%

       RFDC signal waveform

Checking Location: BD board (Side B)(See page 25)

VOLT/DIV: 200 mV
TIME/DIV: 500 ns 

level: 0.6 

±

 0.15 Vp-p

Procedure:
1.

Connect an oscilloscope to test point TP8 (RFAC) and TP7
(VC) on the BD board.

2.

Turn the power on.

3.

Put the disc (YEDS-18) in to playback the number five track.

4.

Confirm that oscilloscope waveform is clear and check RFAC
signal level is correct or not.

A clear RFAC signal waveform means that the shape “

◊

” can be

clearly distinguished at the center of the waveform.

       RFAC signal waveform

Checking Location: BD board (Side B)(See page 25)

+
–

BD board

TP8 (RFAC)

TP7 (VC)

oscilloscope

VOLT/DIV: 200 mV
TIME/DIV: 500 ns 

level: 1.0 

±

 0.4 Vp-p

+
–

BD board

TP2 (TE)

TP7 (VC)

oscilloscope

Procedure:
1.

Connect an oscilloscpe to test point TP2 (TE) and  TP7 (VC)
on the BD board.

2.

AC is put in pushing CD 

u

button to enter the CD test 

mode.

3.

Put the disc (YEDS-18) in to playback the number five track.

4.

Press the                      button. If it plays, press the

CD 

u

  

button again. (The tracking servo and the sledding servo are
turned OFF)

CD 

u

  

IC101

TP7
(VC)

IC103

RV101
E-F Balance
Adjustment

  TP8
(RFAC)

  TP6
(RFDC)

TP4
(FE)

TP2
(TE)