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17

• This mode is used to check the fluorescent indicator tube, LED,

model, destination, software version, volume, key and VACS
level.

1. Press 

x

  button, 

[AMP MENU

]  button and 

[DISC 2]

    button

simultaneously.

2. All LEDs and segments in fluorescent indicator tube are lighted

up.

3. When you want to enter the software version display mode,

press 

[DISC 1]

 button. The model and destination are displayed.

4. Each time 

[DISC 1]

 button is pressed, the display changes from

MC version, GC version, CD version,  ST version, TA version,
TM version and TC version in this order, and returns to the MC
version display.

5. When 

[DISC 3]

 button is pressed while the version numbers

are being displayed except model and destination, the date of
the software creation appear. When 

[DISC 3]

 button is pressed

again, the display returns to the software version display. When

[DISC 1]

 button is pressed while the date of the software creation

is being displayed, the date of the software creation is displayed
in the same order of software version display.

6. Press 

[DISC 2]

 button, the key check mode is activated.

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

“K 0   V 0”.
Each time a button is pressed, “K” value increases. However,
once a button has been pressed, it is no longer taken into account.
“V” value increases in the manner of 0,1, 2, 3 ... if 

[VOLUME]

knob is turned clockwise, or it decreases in the manner of 0, 9,
8,7  ... if 

[VOLUME]

 knob is turned counter-clockwise.

8. When 

[DISC 3]

 button is pressed after all LEDs and segments

in fluorescent indicator tube light up, the fluorescent indicator
tube displays “VACS A + B”. A is VACS level which is trigger
by signal level while B is VACS level which is trigger by thermal.
Total VACS value would be the sum of A and B.

9. When 

[DISC SKIP/EX-CHANGE]

  button is pressed after all

LEDs and segments in fluorescent indicator tube light up,
alternate segments in fluorescent indicator tube would light up.
If you press 

[DISC SKIP/EX-CHANGE]

 button again, another

half of alternate segments in fluorescent indicator tube would
light up.  Pressing 

[DISC SKIP/EX-CHANGE]

  button again

would case all segments lights up.

10. To release this mode, press three buttons in the same manner as

step 1, or disconnect the power cord.

• This mode is used to check operations of the respective sections

of Amplifier, Tuner, and Tape.

Procedure:
*   To enter MC Test Mode

1. Press 

x

  button, 

[AMP MENU]

  button and 

[DISC 3]

  button

simultaneously.

2. The TAPE A and TAPE B segments flash on the fluorescent

indicator tube. The function is changed to VIDEO.

* Check of Amplifier

1. When  

V

  button is pressed, GEQ increases to its maximum and

a message “GEQ MAX” appears on the fluorescent indicator
tube.

2. When  

v

  button is pressed, GEQ decreases to its minimum and

a message “GEQ MIN” appears on the fluorescent indicator
tube.

3.  When  

B

  button or  

b

  button is pressed, GEQ is set to flat and

a message “GEQ FLAT” appears on the fluorescent indicator
tube.

4. When the 

[VOLUME]

 knob is turned clockwise even slightly,

the sound volume increases to its maximum and a message
“VOLUME MAX” appears for two seconds, then the display
returns to the original display.

5. When the 

[VOLUME]

 knob is turned counter-clockwise even

slightly, the sound volume decreases to its minimum and a
message “VOLUME MIN” appears for two seconds, then the
display returns to the original display.

* Check of clock frequency
1. To check the frequency of clock used to run the clock of the

system, the clock output is available at IC501 pin el (CLOCK-
OUT) on the MAIN board during MC test mode.

2. The frequency is 32.768 kHz.

* Tape function
1. When a tape is inserted in Deck B and recording is started, the

function is changed to VIDEO automatically. When 

[CD SYNC]

button is pressed during recording in function, ALC (Automatic
Logic Control) is turned on.

2. After recording is stopped by pressing  

x

  button, press 

m

button will change the function to TAPE B and rewind Tape B
until the recording start position and playback of Tape B is
started. If the 

[REC PAUSE/ START]

  button is pressed for a

pause and pressed again to resume recording during recording
time, when tape deck B is rewind, tape deck B will be rewind
until the position where the pause is applied.

* AMS Test Mode
1. Select the function “TAPE A” or “TAPE B”.
2. Select Loop or Relay direction mode by pressing the

[DIRECTION]

 button. Insert a test tape AMS-110A or AMS-

120 to selected tape deck.

3. Press the 

[AMP MENU]

 button to enter the AMS test mode.

4. After the test tape is rewind to the beginning of the tape, the

AMS+ is checked, and the mechanism is shut off after detecting
the AMS signal twice.

5. Then the AMS- is checked and the mechanism is shut off after

detecting the AMS signal twice.

6. When the check is complete, a message of either OK or NG

appears.

* To release MC Test mode.

1. To release this mode, press 

?/1

 button.

2. The cold reset is enforced at the same time.

18

• 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.

1. Press 

x

  button, 

[AMP MENU]

  button, and 

?/1

  button

simultaneously.

2. The fluorescent indicator tube becomes blank for a while, and

the set is reset.

• This mode is used to switch ON and OFF the VACS (Variable

Attenuation Control System).

1. Press 

?/1

 button to turn the set ON.

2.   Press 

[AMP MENU]

  button and 

[GAME MIXING]

  button

simultaneously. The message “VACS OFF” or “VACS ON”
appears.

• The step interval of AM channels can be toggled between 9 kHz

and 10 kHz.

1. Press 

?/1

 button to turn the set ON.

2. Press 

[TUNER/BAND]

 button to select the “AM”.

3. Press 

?/1

 button to turn the set OFF.

4. Press 

[AMP MENU]

 button and 

?/1

 button simultaneously.

The system will turn ON automatically. The message “AM 9k
STEP” or AM 10k STEP” appears and thus the channel step is
changed.

• The number of repeat for DVD playback is 5 times when the

repeat mode is “REPEAT ALL”. This mode enables DVD to
repeat playback for limitless times.

1. Press 

?/1

 button to turn the set ON.

2. Select CD function.

3. Press 

x

  button, 

[REPEAT]

  button and [DVD]  button

simultaneously to enter the DVD repeat 5 limit off mode.

4. To release this mode, operate the cold reset. (Refer to the “MC

COLD RESET”)

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

vibration and clears all data including preset data stored in the
RAM to initial conditions. Use this mode when returning the
set to the customer after repair.

1. Press 

?/1

 button to turn the set ON.

2. Select DVD function.

3. Press 

x

  button, 

[AMP MENU]

  button and 

[GAME]

  button

simultaneously. The set will power off automatically.

4. After the “STANDBY” blinking display finish, a message

“LOCK” is displayed on the fluorescent indicator tube and the
DVD ship mode is set.

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

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

1. Press 

?/1

 button to turn the set ON.

2. Select DVD function.

3. Press

 [DVD] 

button and 

?/1

 button simultaneously. The set

will power off automatically.

4. After the “STANDBY” blinking display finish, a message

“LOCK” is displayed on the fluorescent indicator tube and the
DVD ship mode is set.

• This mode let you switch on or off power supply to the BU

during TUNER function.

•  When DVD POWER is set to OFF, the power supply to the BU

is cut off during TUNER function. It will increase the time taken
to access DVD when function change from TUNER to DVD
but it will improve tuner reception.

• When DVD POWER is set to ON, the power supply to the BU

is not cut off during TUNER function. It will reduce the time
taken to access DVD when function change from TUNER to
DVD but it will decrease tuner reception performance.

1.  Press 

?/1

 button to turn the set ON.

2. Select DVD function.

3. Press 

?/1

 button to turn the set OFF.

4. Press  

x

  button and 

?/1

 button simultaneously. The set will

power on automatically.

5. The message “DVD POWER ON” or “DVD POWER OFF”

will be displayed on the fluorescent indicator tube.

• This mode let you lock the disc trays. When this mode is acti-

vated, the disc tray will not open when 

Z

OPEN/CLOSE

 but-

ton or 

[DISC SKIP/EX-CHANGE]

 button is pressed. The mes-

sage “LOCKED” will be displayed in the will be displayed on
the fluorescent indicator tube.

1. Press 

?/1

 button to turn the set ON.

2. Select DVD function.

3. Press  

x

  button and 

Z

OPEN/CLOSE

 button simultaneously

and hold down until “LOCKED” or “UNLOCKED” displayed
on the fluorescent indicator tube (around 5 seconds).

• This mode let you switch from MD to VIDEO and vice-versa.

1. Press 

?/1

 button to turn the set ON.

2. Select MD function.

3. Press 

[MD $VIDEO%]

 button and 

?/1

 button simultaneously.

The function will change to VIDEO. Press the same buttons
again to change from VIDEO to MD.

19

Precaution
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.

3.06 N • m to 6.96 N • m

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

0.19 N • m to 0.58 N • m

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

3.06 N • m to 6.96 N • m

31 to 71 g • cm

(0.43 – 0.98 oz • inch)

0.19 N • m to 0.58 N • m

2 to 6 g • cm

(0.02 – 0.08 oz • inch)

6.96 N • m to 14.02 N • m

71 to 143 g • cm

(0.98 – 1.99 oz • inch)

9.80 N • m

100 g or more

(3.53 oz or more)

9.80 N • m

100 g or more

(3.53 oz or more)

CQ-102C

CQ-102C

CQ-102RC

CQ-102RC

CQ-201B

CQ-403A

CQ-403R

FWD

FWD

back tension

REV

REV

back tension

FF/REW

FWD tension

REV tension

0 dB=0.775 V

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 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 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.

• Test Tape

Note:  Perform this adjustments for both decks

Procedure:
1. Mode:  Playback

P-4-A100

10 kHz, –10 dB

Azimuth Adjustment

WS-48B

3kHz, 0dB

Tape Speed Adjustment

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)

20

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.

Adjustment Location: Playback Head (Deck A).

Record/Playback/Erase Head (Deck B).

Screw
position

L-CH
peak

within
1dB

Output
level

L-CH
peak

R-CH
peak

within
1dB

Screw
position

R-CH
peak

MAIN
board
CN301
set

test tape
P-4-A100
(10 kHz, –10 dB)

pin 

3

oscilloscope

L-CH

R-CH

V

H

waveform of oscilloscope

in phase 45

°

90

°

135

°

180

°

good

wrong

pin 

2

pin 

1

L

R

forward

reverse

set

MAIN board
AUDIO OUT jack (J730)
L-CH, R-CH

+
–

frequency counter

test tape
WS-48B
(3 kHz, 0 dB)

1. Insert the WS-48B into the deck B.
2. Press the   H  button on the deck B.
3. Adjust the tape speed adjustment control inside motor so that

frequency counter reads 3,000 

± 90Hz.

Sample value of wow and flutter W.RMS (JIS) less than 0.3%
WS-48B

Tape speed adjustment
control inside motor

Tape Speed Adjustment
   DECK B
Procedure:
Mode: Playback