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21

– MAIN BOARD (Component Side) –

REC LEVEL

ADJUSTMENT

REC BIAS ADJUSTMENT

CN301

IC301

3

1

(R-CH)

(R-CH)

(L-CH)

(L-CH)

RV301

RV351

RV304

RV354





























6. Confirm the playback signal recorded in step 3 becomes

adjustable level as follows.
If these levels are not adjustable level, adjust the RV304 (L-
CH) and RV354 (R-CH) on the MAIN  board to repeat steps 4
and 5.

Adjustable level: Playback output of 315 Hz to playback output

of 10 kHz:  

±1.0 dB

Adjustment Location:  MAIN board

Procedure:
In the MC test mode, the “REC memory mode” is convenient for
this adjustment. In the “REC memory mode” , when the REC starts
the input signal FUNCTION is switched to VIDEO automatically.
When the REC stops, the tape returns near to the recording start
position.

1. Press

MD (VIDEO)

button to select VIDEO. (This step is not

necessary if the above test mode has already been set)

2. Insert a tape into deck B.
3. After press 

[REC PAUSE/START]

 button, press 

[REC PAUSE/

START]

 button, then recording start.

set

MAIN board
MD/VIDEO (AUDIO) IN (J117) 
315 Hz, 50 mV (–23.8 dB)

blank tape
CS-123

600 

Ω

attenuator

AF OSC

+
–

set

recorded
portion

MAIN board
CN301 Pin 

2

 (GND)

MAIN board
CN301
Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

level meter

5. Mode:  Playback

+
–

set

recorded
portion

MAIN board
CN301 Pin 

2

 (GND)

MAIN board
CN301
Pin 

1

 (L-CH)

Pin 

3

 (R-CH)

level meter

4. Mode:  Record

5. Mode:  Playback

6. Confirm the play back signal recorded in step 3 becomes

adjustable level as follows.
If these levels are not adjustable level, adjust the RV301 (L-
CH) and RV351 (R-CH) on the MAIN board to repeat steps 4
and 5.

Adjustable level:
CN301 PB level:  47.2 to 53.0 mV (–24.3 to –23.3 dB)
Adjustment Location:  MAIN board

Procedure:
In the MC test mode, the “REC memory mode” is convenient for
this adjustment. In the “REC memory mode” , when the REC starts
the input signal FUNCTION is switched to VIDEO automatically.
When the REC stops, the tape returns near to the recording start
position.

1. Press

MD (VIDEO)

button to select VIDEO. (This step is not

necessary if the above test mode has already been set)

2. Insert a tape into deck B.
3. After press 

[REC PAUSE/START]

 button, press 

[REC PAUSE/

START]

 button, then recording start.

4. Mode:  Record

attenuator

set

MAIN board
MD/VIDEO (AUDIO) IN (J117)

1) 315 Hz
2) 10 kHz

50 mV (–23.8 dB)







600 

Ω

blank tape
CN-123

AF OSC

22

Note :

1. VIDEO board is basically designed to operate without adjust-

ment. Therefore, check each item in order given.

2. Use DVD reference disc unless othermise indicated.

[DVD reference disc]
• LUV-P01 (4-999-032-01) (CD)
•TDV-540C (J-2501-235-A) (DVD-DL)
• TDV-520CSO (J-2501-236-A) (DVD-SL)

3. Use an oscilloscope with more than 10M

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.

Video Level Check (VIDEO BOARD)
Purpose
This adjustment is made to satisfy the NTSC standard, and if not
adjusted correctly, the brightness will be too large or small.

Procedure:
1. Connect oscilloscope to VIDEO output.
2. Load a DVD reference disc playback.
3. Check the video signal level is 1.00

±0.05Vp-p.

J711
VIDEO OUTPUT

75 

Ω

Oscilloscope

set

1.00 

± 0.05 Vp-p

(WHITE 100%)

RFMON Level Check
Perform a RFMON level check before exchanging optical pick-up.
Connection:

       RFMON signal waveform

• Standard value

DVD

TDV-520CSO

1.09

±0.2Vp-p

(J-2501-236-A)

CD

LUV-PO1

1.05

±0.2Vp-p

(4-999-032-01)

VOLT/DIV: 200 mV
TIME/DIV: 500 ns 

RFMON level

IC001

JL005

(RFMON)

VC

VC

+
–

JL005(RFMON)

oscilloscope

–RF board (side B) –

23

Note on Schematic Diagram:
• All capacitors are in µF unless otherwise noted.  pF: µµF

50 WV or less are not indicated except for electrolytics
and tantalums.

• All resistors are in Ω and 

1

/

4

 

W or less unless otherwise

specified.

•

f

: internal component.

• 2 : nonflammable resistor.
• 5 : fusible resistor.

Note on Printed Wiring Boards:
• X : parts extracted from the component side.
•

: Pattern from the side which enables seeing.

(The other layers´ Patterns are not indicated.)

 

 Caution:

Pattern face side:

Parts on the pattern face side seen from the

(Side B)

pattern face are indicated.

Parts face side:

Parts on the parts face side seen from the

(Side A)

parts face are indicated.

• Indication of transistor.

• C : panel designation.

• A : B+ Line.
• B : B– Line.
• H : adjustment for repair.
• Voltages and waveforms are dc with respect to ground

under no-signal conditions.
RF, DMB03, VIDEO, REGULATOR boards section
   no mark: DVD PLAY
Other board section
   no mark: TUNER (FM/AM)
   (           ): DVD PLAY
   <         >: TAPE PLAY
   [           ]: TAPE REC

• Voltages are taken with a VOM (Input impedance 10 MΩ).

Voltage variations may be noted due to normal produc-
tion tolerances.

• Waveforms are taken with a oscilloscope.

Voltage variations may be noted due to normal produc-
tion tolerances.

• Circled numbers refer to waveforms.

• Signal path.

F

: TUNER (FM/AM)

E

: TAPE PLAY (DECK A)

d

: TAPE PLAY (DECK B)

G

: RECORD

J

: DVD PLAY

c

: DVD PLAY (DIGITAL OUT)

q

: MD/VIDEO (AUDIO) IN

j

: GAME IN (AUDIO)

k : GAME IN (VIDEO)
N

: MIC INPUT

Note:
The components identified by mark 0 or dotted line
with mark 0 are critical for safety.
Replace only with part number specified.

C

B

These are omitted.

E

Q

B

These are omitted.

C

E

Q

B

These are omitted.

C

E

Q

•

Abbreviation
AUS

: Australian model

E3

: 240 V AC Area in E model

EA

: Saudi Arabia model

E15

: Iran model

E51

: Chilean and Peruvian model

MX

: Mexican model

PH

: Philippines model

SP

: Singapore model

MY

: Malaysia model

TH

: Thai model

•

Abbreviation
AUS

: Australian model

E3

: 240 V AC Area in E model

EA

: Saudi Arabia model

E15

: Iran model

E51

: Chilean and Peruvian model

MX

: Mexican model

PH

: Philippines model

SP

: Singapore model

MY

: Malaysia model

TH

: Thai model

24

TUNER PACK

SUB TRANS board

SURROUND board

POWER AMP board

TRANS board

DISPLAY board

VOLUME board

GAME IN board

MOTOR (LD) board

SW board

SENSOR board

RF board

MOTOR (TB) board

DRIVER board

MAIN board

CD SWITCH board

DMB03 board

REGULATOR

board

VIDEO board