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– 9 –

• 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  SPECTRUM ANALYZER  ,  ENTER  , and  DISC 1  simultaneously.
2. The fluorescent indicator tube becomes blank instantaneously, and the set is reset.

• This mode moves the pick-up to the position durable to vibration. Use this mode when returning the set to the customer after repair.
Procedure:
1. Press  1/u  button to turn the set ON.
2. Press  PLAY MODE  button and  1/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  SPECTRUM ANALYZER  ,  ENTER  , and  DISC 2  simultaneously.
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. Select the function “CD”.
2. Press three buttons  SPECTRUM ANALYZER  ,  ENTER  , and  FUNCTION  simultaneously.
3. The Sled Servo mode is selected, if “CD” is blanking on the fluorescent indicator tube.
4. With the CD in stop status, press  )  button in CD section to move the pick-up to outside track, or  0  button to inside track.
5. 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 2.

Note:
• 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.

• The FUNCTION name of external input terminal can be changed over to VIDEO or MD. With the FUNCTION selected to “MD”, about

5dB mute is applied to the input gain.

Procedure:
1. Press  1/u  button to turn the set OFF.
2. Press  1/u  button together with  FUNCTION  button, and the power is turned on, the display of fluorescent indicator tube changes to

“MD” or “VIDEO” instantaneously, and thus the FUNCTION is changed over.

• A step of AM channels can be changed over between 9kHz and 10kHz.
Procedure:
1. Press  1/u  button to turn the set ON.
2. Select the function “TUNER”, and press  TUNER/BAND  button to select the BAND “AM”.
3. Press  1/u  button to turn the set OFF.
4. Press  ENTER/NEXT  and  1/u  buttons simultaneously, and the display of  fluorescent indicator tube changes to “AM 9k STEP” or “AM

10k STEP”, and thus the channel step is changed over.

Procedure:
1. Press three buttons  SPECTRUM ANALYZER  ,  ENTER  , and  DISC 3  simultaneously.
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 increases. However,

once a button is pressed, it is no longer taken into account.
“J” Value increases like 1, 2, 3 ... if rotating  ≠ AMS ±  (JOG) knob in “+”  direction, or it decreases like 0, 9, 8 ... if rotating in “-”
direction.
“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 manner as step 1, or disconnect the power cord.

– 10 –

This mode can be used for operation check of CD section and tape deck section.
• If an error occurred:

The aging operation stops.

• If no error occurs:

The aging operation continues repeatedly.

1-1. Operating procedure of Aging Mode

1. Set discs in DISC 1 and DISC 3 trays.
2. Select the function “CD”.
3. Press three buttons  SPECTRUM ANALYZER  ,  ENTER  , and  KARAOKE PON/MPX  simultaneously.
4. The aging mode is activated, if a roulette mark on the fluorescent indicator tube is blinking.
5. In the aging mode, the aging is executed in a sequence given in “1-2. Operation during Aging Mode”.

The aging continues unless an alarm occurred.

6. To exit from the aging mode, press  1/u  button to turn the set OFF.

• If a button other than buttons In CD section is pressed during aging, the aging in the CD section is finished.
• To execute aging to the tape deck section successively, press  ·  button in the deck A.

“AGING” is displayed on the fluorescent indicator tube.  (For the aging in tape deck, see “2. Aging Mode in Tape Deck Section”.

1-2.  Operation during aging Mode
In the aging mode, the program is executed in the following sequence.

1. The disc tray turns to select a disc. (For a disc selection sequence, see Section 1-3.)
2. TOC of disc is read.
3. The pick-up accesses to the last track.
4. Steps 1 through 3 are repeated.

1-3.  Disc Selection Sequence

• During the aging mode, discs are selected in the following sequence:

Disc 1 

→

 Disc 3

↑

↓

Disc 3 

←

 Disc 1

2-1.  Operating procedure of Aging Mode

1. Load a commercially available 10-minute tape into the decks A and B respectively.

(If a 10-minute tape is not available, another tape may be used but a cycle time will be longer.)

2. Select the function “TAPE”.
3. Rewind tapes in advance by pressing  0  button respectively on decks A and B.
4. Press three buttons  SPECTRUM ANALYZER  ,  ENTER  , and  KARAOKE PON/MPX  simultaneously.
5. Press  ·  button on deck A.  (This button triggers the aging mode.)
6. The aging mode is activated if “AGING A” is displayed on the fluorescent indicator tube.
7. In the aging mode, the aging is executed in a sequence given in “2-2.  Operation during Aging Mode”.

The aging continues unless an alarm occurred.

8. To exit from the aging mode, press  1/u  button to turn the set OFF.

2-2.  Operation during Aging Mode
In the aging mode, the program is executed in the following sequence.

1. A tape on FWD side is played for one minute.
2. PAUSE STOP is made.
3. Recording is made for 3 minutes. (For the deck not having the record function, the play is executed.)
4. FF is executed up to the end of tape.
5. A tape is reversed, and the tape on REV side is played for one minute.
6. PAUSE STOP is made.
7. Recording is made for 3 minutes.  (For the deck not having the record function, the play is executed.)
8. FF is executed up to the end of tape.
9. Steps 1 through 8 are executed for the other deck.
10. Steps 1 through 9 are repeated unless an alarm occurred.

2-3.  Deck Selection Sequence

• During the aging mode, decks are selected in the following sequence:

Deck A (FWD) 

→

 Deck A (REV)

↑

↓

Deck B (REV) 

←

 Deck B (FWD)

– 11 –

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 microcom-
puter (IC701).
The results can be checked by connecting an oscilloscope to TP709
(LED) of the VIDEO board.

Oscilloscope (Waveform)

Symptom

H

L

Light

H

L

1 time blinking

H

L

3 time blinking

No error

DRAM (IC251) error

H

L

2 time blinking

External SRAM (IC751)
error

MPEG decoder (IC201)
error

oscilloscope

VIDEO board
TP709 (LED)

+
–

X901

TP709 (LED)

IC751

IC251

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 (IC701) 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 J9001 (VIDEO
OUT) and the sound signal can be observed at J101 (VIDEO (AU-
DIO) OUT) using an oscilloscope.
1. Connect the lead wire to both ends of the land of SL701 (CAL

BAR) 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.
NOTE:
The 1 kHz sine wave is not outputted when the CD is played once,
but it is not error.

SL703 (AFADJ)

IC751

IC251

SL702 (ADJ)

SL701 (CAL BAR)

• Refer to SECTION 6 ELECTRICAL ADJUSTMENTS page 15.

1. Connect the lead wire to both ends of the land of SL702 (ADJ)

and SL703 (AFADJ) of the VIDEO board.

2. Turn the power on. Press  FUNCTION  button to select CD.
3. Short-circuit the lead wire. (At this time, “DISC” on the fluores-

cent indicator tube will blink (test mode). If it is not blinking,
perform from step 1 again.)

4. Press the  ·  button in playback.
5. Every pressing the  REPEAT  button, the tracking servo and the

sledding servo are turned on or off.

6. When the servo is OFF, the counter on front panel will not be

changed.

7. After measuring, remove the lead wire connected step 1.

– 12 –

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 sup-

ply voltage unless otherwise noted.

2 to 6 g • cm

(0.02 - 0.08 oz • inch)

36 to 61 g • cm

(0.5 - 0.84 oz • inch)

Mode

Torque meter

FWD

FWD
back tension

REV

FF/REW

REV
back tension

FWD tension

REV tension

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

36 to 61 g • cm

(0.5 - 0.84 oz • inch)

2 to 6 g • cm

(0.02 - 0.08 oz • inch)

61 to 143 g • cm

(0.85 - 1.99 oz • inch)

100 g or more

(3.53 oz or more)

100 g or more

(3.53 oz or more)

Meter reading

1. Demagnetize the record/playback head with a head damagnetizer.
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 sup-

ply 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 adjust-
ment.)

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

Signal

Used for

Tape

Azimuth Adjustment

Tape Speed Adjustment

Level Adjustment

10 kHz, –10 dB

3 kHz, 0 dB

315 Hz, 0 dB

P-4-A100

WS-48B

P-4-L300

test tape
P-4-A100
(10kHz, –10dB)

main board
CN403
Pin 

3

 (L-CH)

Pin 

1

 (R-CH)

level meter

set

main board
CN403
Pin 

2

 (GND)