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This mode is used to check the fl uorescent indicator tube, LEDs, 
keys, [MASTER VOLUME] jog, [OPERATION DIAL] jog, mod-
el, destination and software version.
Procedure:
1. Press 

[

x

], button, [METER MODE] button and [DISC SKIP/

EX-CHANGE] button simultaneously.

2.  All LEDs and segments in fl uorescent indicator tube are light-

ed up.

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

press [DISC 1] button. The model information appears on the 
fl uorescent indicator tube.

 

  •  “GVX 7S”  is shown for MHC-GTR88.

 

    Press [DISC 1] button again to view the destination 

information.

4.  During the destination information display, press [DISC 1] 

button. Each time [DISC 1] button is pressed, the fl uorescent 
indicator tube shows the version of each category software in 
the following sequence: SC, MTK (DMB Board fi rmware ver-
sion), GC, SYS, CD, CDMA, CDMB, ST, TC TA, TM, MTR 
(METER) and return back to model information 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 appears. When [DISC 3] button is 
pressed again, the display returns to the software version dis-
play. 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 dis-
play.

6.  Press [DISC 2] button, the key check mode is activated.
7.  In the key check mode, the fl uorescent indicator tube displays 

“K0 V0”.

 

Each time a button is pressed, “K” value increases. However, 
once a button has been pressed, it is no longer taken into ac-
count. 

  

“V” value increases in the manner of 0, 1, 2, 3 ... if [MASTER 
VOLUME] knob is turned clockwise, or it decreases in the 
manner of 0, 9, 8, 7  ... if [MASTER VOLUME] knob is turned 
counterclockwise.

8.  When [DISC SKIP/EX-CHANGE] button is pressed after all 

LEDs and segments in fl uorescent indicator tube light up, al-
ternate segments in fl uorescent indicator tube and LEDs would 
light up. If you press [DISC SKIP/EX-CHANGE] button 
again, another half of alternate segments in fl uorescent indi-
cator tube and LEDs would light up.  Pressing [DISC SKIP/
EX-CHANGE] button again would cause all segments in fl uo-
rescent indicator tube and LEDs light up.

9.  To release from 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 Amplifi er section.

To enter Common Test Mode
Procedure:
1. Press [

x

], button, [METER MODE] button and [OPEN/

CLOSE] button simultaneously.

2.  The CD ring indicators fl ash on the fl uorescent indicator tube. 

The function is changed to AUDIO and the volume is changed 
to VOLUME MIN.

Check of Amplifi er
Procedure:
1.  Press [EQ BAND/SURROUND] button repeatedly until a 

message “GEQ MAX” appears on the fl uorescent  indicator 
tube. GEQ increases to its maximum.

2.  Press [EQ BAND/SURROUND] button repeatedly until a 

message “GEQ MIN” appears on the fl uorescent  indicator 
tube. GEQ decreases to its minimum.

3.  Press [EQ BAND/SURROUND] button repeatedly until a 

message “GEQ FLAT” appears on the fl uorescent  indicator 
tube. GEQ is set to fl at.

4.  When the [MASTER VOLUME] knob is turned clockwise 

even slightly, the sound volume increases to its maximum and 
a message “VOLUME MAX” appears on the fl uorescent indi-
cator tube.

5.  When the [MASTER VOLUME] knob is turned counterclock-

wise even slightly, the sound volume decreases to its minimum 
and a message “VOLUME MIN” appears on the fl uorescent 
indicator tube.

To release from Common Test mode
1.  To release from this mode, press [

?/1

 STANDBY] button.

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

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

[

?/1

 STANDBY] button to turn on the system.

2. Press 

[

x

] button, [ENTER] button, and [

?/1

 STANDBY] but-

ton simultaneously.

3.  “COLD RESET” appears on the fl uorescent indicator tube. 

After that, the fl uorescent indicator tube becomes blank for a 
while, and the system is reset.

This mode is used to switch ON and OFF the VACS (Variable At-
tenuation Control System).
Procedure:
1. Press 

[

?/1

 STANDBY] to turn on the system.

2. Press 

[

x

] button, [RETURN], and [DISPLAY] button simul-

taneously. The message “VACS OFF” or “VACS ON” appears 
on the fl uorescent indicator tube.

The step interval of AM channels can be toggled between 9 kHz 
and 10 kHz.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Press [TUNER/BAND] button repeatedly to select the “AM”.
3. Press 

[

?/1

 STANDBY] button to turn off the system.

4.  Press [ENTER] button and [

?/1

 STANDBY] button simulta-

neously. The system turns on automatically. The message “AM  
9K STEP” or “AM 10K STEP” appears on the fl uorescent in-
dicator tube and thus the channel step is changed.

This mode moves the optical pick-up to the position durable to 
vibration and clears all data including preset data stored in the EE-
PROM to initial conditions during the next AC-In. Use this mode 
when returning the set to the customer after repair.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Select CD function.
3. Press 

[x] button, [OPEN/CLOSE] button and [

?/1

 STAND-

BY] button simultaneously. The system turns off automati-
cally.

4.  After the “STANDBY” blinking display fi nishes, a message 
     “MECHA LOCK” is displayed on the fl uorescent indicator tube 

and the CD 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.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Select CD function.
3.  Press [DISC SKIP/EX-CHANGE] button and [

?/1

 STAND-

BY] button simultaneously. The system turns off automati-
cally.

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

“MECHA LOCK” is displayed on the fl uorescent  indicator 
tube and the CD ship mode is set.

This mode let you lock the disc tray. When this mode is activat-
ed, the disc tray will not open when [Z  OPEN/CLOSE] button 
or [DISC SKIP/EX-CHANGE] button is pressed. The message 
“LOCKED” will be displayed on the fl uorescent indicator tube. 
This mode only applied when there is disc(s) on the tray. 
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Select CD function.
3. Press [x] button and [Z  OPEN/CLOSE] button simultane-

ously and hold down until “LOCKED” or “UNLOCKED” dis-
played on the fl uorescent indicator tube (around 5 seconds).

This mode is use to load all the factory use preset frequencies 
into FM 1-FM 20 and AM 1-AM 10. Originally, frequency of FM 
1-FM 20 and AM 1-AM10 are set to the minimum frequency.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Press [EQ BAND/SURROUND], [x] button, and [DISC 1] 

button simultaneously and the message “FACTORY” appears 
on the fl uorescent indicator tube. The function is changed to 
TUNER automatically.

This mode is used to check the VACS level.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Press [ERASE], [x] button and [ENTER] button simultane-

ously.

3. The 

fl uorescent indicator tube displays “V0AP0”.

 

“V” represents Conventional VACS (Triggered by signal level)
“AP” represents AP VACS (Abuse Protection Variable Attenu-
ation Control System)

 

• To release from VACS display mode

 

  To release from this mode, do the step (2) again.

This mode is used to display the total count of meter pointer touch 
initial switch and max switch.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2. Press 

[x] button, [ENTER] button and [DISPLAY] button si-

multaneously.

3. The 

fl uorescent indicator tube displays “IxxxxxMyyyyy”. 

 

“I” represents the Initial Switch touch. 

 

“xxxxx” represents the total count of Initial Switch touch.

 

(Maximum Value of “xxxxx” = 65535)

 

“M” represents the Max Switch touch. 

 

“yyyyy” represents the total count of Max Switch touch.

 

(Maximum Value of “yyyyy” = 65535)

 

• To release from Meter Switch Touch Count Display Mode.

To release from this mode, do the step (2) again.
The fl uorescent indicator tube displays “MODE OUT”.

This mode is used to check the meter device.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2. Press 

[x] button, [ENTER] button and [METER MODE] but-

ton simultaneously.

3.  Meter Backlight LEDs, Meter Pointer LEDs, Power Illumina-

tor LEDs and fl uorescent indicator tube are lighted up. 

4.  When you want to perform count total step from Initial Switch 

to Max Switch operation mode, press [M/>/TUNING +] 
button. The meter pointer will move from Initial Switch to 
Max Switch and fi nally move back to the middle position. The 
total step count information appears on the fl uorescent indica-
tor tube. “xxx STP yy” is shown.

 

“xxx” represents the total step.

 

(Value of “xxx” should between 430 steps to 470 steps)

 

“yy” represents the status of total step count.

 

(If total step between 430 steps to 470 steps, “yy” is OK, Else 
“yy” is NG)

5.  When you want to perform count total step from Max Switch 

to Initial Switch operation mode, press [m/./TUNING –] 
button. The meter pointer will move from Max Switch to Ini-
tial Switch and fi nally move back to the middle position. The 
total step count information appears on the fl uorescent indica-
tor tube. “xxx STP yy” is shown.

 

“xxx” represents the total step.

 

(Value of “xxx” should between 430 steps to 470 steps)

 

“yy” represents the status of total step count.

 

(If total step between 430 steps to 470 steps, “yy” is OK, else 
“yy” is NG)

 

• To release from Meter Test Mode.

 

  To release from this mode, do the step (2) again.

  

The 

fl uorescent indicator tube displays “TST MODE OUT”. 

This mode is used to display the total count of all disc playing.
Procedure:
1. Press 

[

?/1

 STANDBY] button to turn on the system.

2.  Select CD function and All DISC play mode.
3.  Put discs on all trays and close the tray.
4.  Press [GROOVE] button, [x] button and [RETURN] button 

simultaneously.

5. The fl uorescent indicator tube displays Aging Display “AG 

xxxx/yyyy”. 

 

“xxxx” represents the error counter

 

(Maximum Value of “xxxx” = 9999)

 

“yyyyy” represents the cycle counter

 

(Maximum Value of “yyyy” = 9999)

6. Press 

[m/./TUNING –] or [M/>/TUNING +]  to 

search for Aging History Error Display

 The 

fl uorescent indicator tube displays “Mx E1E2E3E4”. 

 

x: error history number

 

E1: Loading sequence JCP high

 

E2: Loading sequence JCP low

 

E3: Loading operation JCP

 

E4: Cam position operation JCP

7.  Press [RETURN] to Aging Display  
 

•  To release from CDM Aging Mode.

 

  To release from this mode, press [

?/1

 STANDBY] button or 

perform COLD RESET operation. 

PRECAUTION
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 demag-

netizer. (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-102AS

2.0 – 8.0 mN • m 

(20 to 80 g • cm)

(0.28 – 1.12 oz • inch)

FWD Back Tension

CQ-102C

0.15 – 0.6 mN • m 

(1.5 to 6 g • cm)

(0.021 – 0.083 oz • inch)

FF

CQ-201AS

5 – 17.7 mN • m 

(50 to 177 g • cm)

(0.7 – 2.48 oz • inch)

REV

CQ-201B

5 – 17.7 mN • m 

(50 to 177 g • cm)

(0.7 – 2.48 oz • inch)

FWD

CQ-403A

more than 80 g

(more than 2.82 oz)

Procedure:
1.  Turn the power on.
2.  Input the following signal from signal generator to FM antenna 

input directly.

 
*  Carrier frequency  : A = 87.5 MHz, B = 98 MHz, C = 108 MHz
  Deviation 

: 75 kHz

  Modulation 

: 1 kHz

  ANT input 

: 35 dBu (EMF)

Note: Use 75 ohm coaxial cable to connect signal generator and the set. 

You cannot use video cable for checking.

 

  Use signal generator whose output impedance is 75 ohm. 

 
3.  Set to FM tuner function and tune A, B and C signals.
4. Confi rm “TUNED” is lit on the display for A, B and C signals.

When mark of “TUNED” means “The selected station signal is 
received in good condition.”

(For African model only)
1.  Demagnetize the record/playback head with a head demagne-

tizer.

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

P-4-A063

6.3 kHz, -10 dB

Azimuth Adjustment

RECORD/PLAYBACK  HEAD  AZIMUTH  ADJUSTMENT
Procedure:
1.  Mode:  Playback

Ω)

0dB = 0.775V

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

q

q 135q 180q

4.  After the adjustments, apply suitable locking compound to the 

pats adjusted.

Adjustment Location: Record/Playback/Erase Head