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17

The cold reset clears all data including preset data stored in the
memory to initial conditions. Execute this mode when returning
the set to the customer.
Procedure:

1. In the standby status, press the  @/1  button to turn the power

on.

2. Press three buttons of [DSGX],  x , and at last   @/1  simulta-

neously.

3. When “RESET” appears, the machine enters standby status.

1. In the standby status, press the  @/1  button to turn the power

on.

2. Press three buttons of [DISPLAY], x , and [DSGX] simulta-

neously.

3. When the panel test mode is activated, LEDs and segments of

LCD are all turned on.

1. In the panel test mode (all LEDs and segments of LCD are

turned on), press the [FUNCTION] button.

2. On the LCD, date and version are displayed “xxxxxxxx”.

For example, “0317V004”.

3. From this status, press the [TUNER/BAND]  button, and the

destination is displayed. For example, “EC50DC”

4. To release from this mode, press three buttons of [DISPLAY],

x , and [DSGX] simultaneously.

Number of repeats for CD playback is 5 times when the repeat mode
is “REPEAT”. This mode enables CD to repeat playback for limitless
times.
Procedure:

1. Press the  @/1  button to turn the power on.
2. Press the [FUNCTION] button to select CD function.
3. Press three buttons of  CD u , [DSGX], and [DISPLAY] si-

multaneously.

4. It enters the CD repeat 5 limit cancel mode and displays “NO

LIMIT”

5. To release this mode, press the  @/1  button to turn the power

off.

This mode can run the CD sled motor optionally. Use this mode, for
instance, when cleaning the optical pick-up.
Procedure:

1. Press the  @/1  button to turn the power on.
2. Press the [FUNCTION] button to select CD function.
3. Press two buttons of  CD u  and  @/1  simultaneously. *1
4. Set to the CD ship mode. (chucking on)
5. After blink “STANDBY”, “LOCK” is displayed, disconnect

the AC plug.
*1) If press three buttons of [DISC 3],  x  and  @/1  simulta-

neously, activate the CD ship mode and MC cold reset.

This mode is for the antitheft of CD disc in shop. (not for transport)
Procedure:

1. Press the  @/1  button to turn the power on.
2. Press the [FUNCTION] button to select CD function.
3. Insert a disc.
4. While pressing the  x  button, press the [DISC 1] button for

more 5 seconds.

5. The message “LOCKED” is displayed and the disc slot is

locked. (Even if exiting from this mode, the disc slot is still
locked)

6. If press the  Z  button to eject the disc, the message

“LOCKED” is displayed and can not eject the disc.

7. To release this lock, while pressing the  x  button, press the

[DISC 1] button for 5 seconds again.

8. The message “UNLOCKED” is displayed and the disc slot is

unlocked.

This mode is for switch the CD power supply on/off. Even if this
state pulls out AC plug, it is held.
Procedure:

1. Press the  @/1  button to turn the power on.
2. Press the [FUNCTION] button to select CD function.
3. Press the  @/1  button again to turn the power off (standby).
4. After pressing the [DISPLAY] button, while pressing the  x

button, press the  @/1  button.

5. It turns power on and display “CD POWER”, then display

“ON” or “OFF”.

The AM tuning interval can be changed over 9 kHz or 10 kHz.
Procedure:

1. Press the  @/1  button to turn the power on.
2. Press the [TUNER/BAND]  button to select TUNER (AM)

function.

3. Press the  @/1  button again to turn the power off (standby).
4. After pressing the [DISPLAY]  button, while pressing the

TUNING+ J  button, press the  @/1  button.

5. It turns power on and display “9k STEP” or “10k STEP”, and

thus the tuning interval is changed over.

18

1. Mode:  Playback

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.

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position 

R-CH
peak

0 dB=0.775 V

set

JACK board
PHONES jack
(J102)

+
–

level meter 

test tape
P-4-A063
(6.3 kHz, 

−

10 dB)

1. Demagnetize the record/playback head with a head

demagnetizer.

2. Do not use a magnetized screwdriver for the adjustments.

•

P-4-A063

6.3 kHz, –10 dB

Azimuth Adjustment

set

test tape
P-4-A063
(6.3 kHz, 

−

10 dB)

oscilloscope

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

JACK board
PHONES jack
(J102)

•

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. (Do not bring the head magnetizer close to the
erase head.)

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.

•

•

FWD

CQ-403A

more than 80 g

(more than 2.82 oz)

2.0 – 8.0 mN • m

(20 to 80 g • cm)

(0.28 – 1.12 oz • inch)

0.15 – 0.6 mN • m

(1.5 to 6 g • cm)

(0.021 – 0.083 oz • inch)

5 – 17.7 mN • m

(50 to 177 g • cm)

(0.7 – 2.48 oz • inch)

5 – 17.7 mN • m

(50 to 177 g • cm)

(0.7 – 2.48 oz • inch)

CQ-102AS

CQ-102C

CQ-201AS

CQ-201B

FWD

FWD

back tension

FF

REW

19

+
–

BD83S board

TP (RFACI)
TP (VC)

oscilloscope 

(DC range) 

1. Connect oscilloscope to TP (RFACI) and TP (VC) on the

BD83S board.

2. Press the ?

/

1 button to turn the power ON, and press

the Z (CD) button to open the CD disc tray.

3. Set disc (YEDS-18) on the tray and press the

CD

 u button

to playback.

4. Confirm that oscilloscope waveform is as shown in the figure

below. (eye pattern)
A good eye pattern means that the diamond shape (

◊

) in the

center of the waveform can be clearly distinguished.

VOLT/DIV: 200 mV 
TIME/DIV: 500 ns

level:
0.9 

±

 0.4 Vp-p

TP

(VC)

TP

(RFACI)

IC201

1.

CD Block is basically constructed to operate without adjustment.

2.

Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.

3.

Use an oscilloscope with more than 10 M

Ω

 impedance.

4.

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

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

5.

Check the focus bias check when optical pick-up block is replaced.

Adjustment Location: Record/Playback/Erase Head

20

0 dB=1 

µ

V

Setting:
FUNCTION: TUNER
TUNER/BAND button: AM

Setting:
FUNCTION: TUNER
TUNER/BAND button: FM

•

Repeat the procedures in each adjustment several times.

AM RF signal 

generator

30% amplitude 

modulation by 

400 Hz signal

Output level: 54 dBuV

60 cm

set

loop antenna A loop antenna B

+
–

level meter

32 

Ω

JACK board

PHONES jack (J102)

FM RF signal

generator

75kHz frequency
deviation by 1K Hz
signal
Output level: as low as possible
                         (8dBuV)

+
–

level meter

set

32 

Ω

0.01 

µ

F

JACK board
PHONES jack (J102)

MAIN board

ANTENNA

CNP802 pin 

1

MAIN board

ANTENNA

CNP802 pin 

2

digital voltmeter

100 k

Ω

MAIN board

TP (TUNER VT)

Adjustment Part

Frequency Display

Reading on Digital Voltmeter

L852

531 kHz

1.5 

±

 0.1 V

Confirmation

1,602 kHz

7.2 

±

 0.5 V

Adjust for a maximum reading on level meter

L851

531 kHz

Adjustment Part

Frequency Display

Reading on Digital Voltmeter

L805

87.5 MHz

1.75 

±

 0.1 V

Confirmation

108 MHz

6.2 

±

 0.5 V

Adjust for a maximum reading on level meter

L804

98 MHz

Adjustment Location: MAIN board (See page 21).

Setting:
FUNCTION: TUNER
TUNER/BAND button: FM

1. Tune the set to 98 MHz.
2. Adjust L806 so that modulation distortion may become the

best in the vicinity of the maximum value where the tuner out
level becomes –15dBuV or more.

FM RF signal

generator

Carrier frequency: 98MHz
Modulation:
deviation by FM 75 kHz
Output level: 60 dBuV

+
–

level meter

MAIN board
TP(TUNER-GND)

MAIN board
IC801 pin 

qs

(TUNER OUT L-ch)

set

MAIN board
ANTENNA
CNP802 pin 

2

MAIN board
ANTENNA
CNP802 pin 

1