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– 13 –

• The cold reset clears all data including preset data stored in the

RAM to initial conditions. Execute this mode when returning
the set to the customer.

Procedure:
1. Press three buttons

p

 , 

[ENTER/NEXT]

, and

u

simulta-

neously.

2. The fluorescent indicator tube becomes blank instantaneously,

and the set is reset.

• This mode moves the pick-up to the position durable to vibra-

tion. Use this mode when returning the set to the customer after
repair.

Procedure:
1. Press

u

button to turn the set ON.

2. Press 

[CD LOOP]

 button and

u

button simultaneously.

3. A message “LOCK” is displayed on the fluorescent indicator

tube, and the CD delivery mode is set.

• This mode resets the set with the preset data kept stored in the

memory.  The hot reset mode functions same as if the power
cord is plugged in and out.

Procedure:
1. Press three buttons

p

, 

[ENTER/NEXT]

, and 

[DISC 1]

 simul-

taneously.

2. The fluorescent indicator tube becomes blank instantaneously,

and the set is reset.

• This mode can run the CD sled motor freely. Use this mode, for

instance, when cleaning the pick-up.

Procedure:
1. Press

u

button to turn the set ON.

2. Select the function “CD”.
3. Press three buttons

p

 , 

[ENTER/NEXT]

, and

§ simulta-

neously.

4. The Sled Servo mode is selected, if “CD” is blanking on the

fluorescent indicator tube.

5. With the CD in stop status, press

) + button to move the

pick-up to outside track, or – 

0 button to inside track.

6. To exit from this mode, perform as follows:

1) Move the pick-up to the most inside track.
2) Press three buttons in the same manner as step 3.

 • Always move the 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.

• A step of MW channels can be changed over between 9 kHz

and 10 kHz.

Procedure:
1. Press

u

button to turn the set ON.

2. Select the function “TUNER”, and press 

[TUNER BAND]

button to select the BAND “MW”.

3. Press

u

button to turn the set OFF.

4. Press 

[ENTER/NEXT]

 and

u

buttons simultaneously, and

the display of  fluorescent indicator tube changes to “MW 9 k
STEP” or “MW 10 k STEP”, and thus the channel step is
changed over.

Procedure:
1. Press three buttons

p

, 

[ENTER/NEXT]

, and 

[DISC 2]

 simul-

taneously.

2. LEDs and fluorescent indicator tube are all turned on.

Press 

[DISC 2]

 button, and the key check mode is activated.

3. In the key check mode, the fluorescent indicator tube displays

“K 1 J0 V0”.  Each time a button is pressed, “K” value in-
creases. However, once a button is pressed, it is no longer taken
into account.
“J” value increases like 1, 2, 3 ... if rotating 

[JOG]

 dial in “+”

direction, or it decreases like 0, 9, 8 ... if rotating in “–” direc-
tion.
“V” value increases like 1, 2, 3 ... if rotating 

[VOLUME]

 knob

in “+”  direction, or it decreases like 0, 9, 8 ... if rotating in
“–” direction.

4. To exit from this mode, press three buttons in the same man-

ner as step 1, or disconnect the power cord.

– 14 –

This mode can be used for checking the operations of the CD player
and tape deck.
• When problems occur:

Aging stops. If currently aging the tape deck, the state when
aging stops will be displayed on the fluorescent display tube.

• When no problems:

Aging continues.

Preparations:
• Set the CD on the DISC 1 tray.
• Insert a commercially available tape for recording (tapes which

contents can be erased, etc.) in decks A and B.

Setting the aging mode:
Press the

p

button, 

[ENTER/NEXT]

 button, and

[DISC SKIP/EX-CHANGE]

 button together. When the aging mode

is set, the CD roulette work blinks. To exit the mode, press the

u

button and turn OFF the power.

Sequence:
The aging mode is executed in the following sequence.
If the function is set to “CD” when the aging mode is set, aging is
performed starting from the CD player. When set to “TAPE A” or
“TAPE B” aging is started from deck A.
If the function is to others aging will not be stated until the func-
tion is switched to CD or TAPE.

Display of status:
• The aging status is displayed on the fluorescent display tube.

(Only when executing the tape deck section.)

• During the aging of the tape deck, the operations performed

will be displayed. If operations ended abnormally, this will be
displayed at the fluorescent indicator tube.

Display of Operations

Operation

Timing of Ending

TAPE A AG-1

TAPE A REW

Shutoff

TAPE A AG-2

TAPE A FWD

2 minute playback

TAPE A AG-3

TAPE A FF

20 seconds or shutoff

TAPE A AG-4

TAPE A REV

2 minutes playback

TAPE A AG-5

TAPE A REW

Shutoff

TAPE B AG-1

TAPE B REW

Shutoff

TAPE B AG-2

TAPE B FWD

2 minute playback

TAPE B AG-3

TAPE B FF

20 seconds or shutoff

TAPE B AG-4

TAPE B REV

2 minute playback

TAPE B AG-5

TAPE B REW

Shutoff

Aging of CD player (12 minutes)

Aging of deck A

Aging of deck B

Maximum about 12 minutes

Operations during aging
• Operations are performed in the following sequence during ag-

ing.

1. The CD tray rotates and disc 1 is selected.
2. Chucking is performed.
3. TOC is read.
4. Track 1 played back for 8 seconds.
5. The CD tray opens and closes again.
6. 1 to 5 is repeated.
7. After 12 minutes of aging, aging is switched to the tape deck.

1. The tape in deck A is rewound to the head.
2. The FWD side is played back for 2 minutes.
3. The tape is fast forwarded (FF) for 20 seconds. The following

procedure is performed when the tape end is reached before
the 20 seconds.

4. The REV side is played back for 2 minutes.
5. The tape is rewound to the head (REW).
6. The tape in deck B is rewound to the head.
7. The FWD side is played back for 2 minutes.
8. The tape is fast forwarded (FF) for 20 seconds. The following

procedure is performed when the tape end is reached before
the 20 seconds.

9. The REV side is played back for 2 minutes.
10.  The tape is rewound to the head (REW).
11. Aging is switched to the CD player.

– 15 –

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 J302
(VIDEO OUT) and the sound signal can be observed at J101
(VIDEO/MD (AUDIO) OUT) using an oscilloscope.
Procedure:
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.

 

(Side A)

 

(Side B)

D502

SL501

SL503

SL502

IC505

SL503

IC502

CN501

CN503

SL502

SL501

– 16 –

Mode

Torqu Meter

Meter Reading

FWD

CQ-102C

31 to 71 g•cm

(0.43 – 0.98 oz•inch)

FWD

CQ-102C

2 to 6  g•cm

Back Tension

(0.02 – 0.08 oz•inch)

REV

CQ-102RC

31 to 71 g•cm

(0.43 – 0.98 oz•inch)

REV

CQ-102RC

2 to 6 g•cm

Back Tension

(0.02 – 0.08 oz•inch)

FF/REW

CQ-201B

71 to 143 g•cm

(0.98 – 1.99 oz•inch)

FWD tension

CQ-403A

100 g or more

(3.53 oz or more)

REV tension

CQ-403R

100 g or more

(3.53 oz or more)

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.

0 dB=0.775 V

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. 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

  Perform this adjustments for both decks

Procedure:
1. Mode:  Playback (FWD)

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.

set

MAIN board
CN301
Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

MAIN board
CN301
Pin 

2

 (GND)

+
–

level meter

test tape
P-4-A100
(10 kHz, –10 dB)

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak