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9

+

–

NTSC pattern
generator

MONITOR OUT

Monitor
XVM-W71

Regulated DC
power supply

ACC cord

Parking

VIDEO OUT
(75 

Ω

)

Tuner unit
XT-992V

INPUT (1)
(VIDEO)

The measuring equipment below are used for these electrical
adjustments:
• Oscilloscope
• NTSC pattern generator
• Regulated DC power supply
• Digital voltmeter

Unless otherwise specified, the measuring equipment should be
connected as shown below:

Set to the VISUAL STD mode.
The adjustment signal is a 5-step gray scale signal from a NTSC
pattern generator.
Input the gray scale signal into the tuner unit and connect an oscil-
loscope to TP9 on the MONITOR board. Check that the width
between the black and white levels of the gray scale signal is 0.74
Vp-p.

0.74Vp-p

white

black

Setup to switch position:
DIMMER switch (S801) ...................................................... HIGH

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect a digital voltmeter to TP22 on the MONITOR board.
3. Adjust RV201 so that the reading on the digital voltmeter is

5.27 ± 0.04 V.

Adjustment Location: See page 12.

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect a digital voltmeter to TP206 on the MONITOR  board.
3. Adjust RV601 so that the reading on the digital voltmeter is

6.80 ± 0.04 V.

Adjustment Location: See page 12.

γ

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect a digital voltmeter to TP519 on the MONITOR board.
3. Adjust RV405 so that the reading on the digital voltmeter is

2.48 ± 0.04 V.

Adjustment Location: See page 12.

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect a digital voltmeter to TP517 on the MONITOR board.
3. Adjust RV407 so that the reading on the digital voltmeter is

1.89 ± 0.04 V.

Adjustment Location: See page 12.

γ

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect an oscilloscope to TP518 on the MONITOR board.
3. Adjust RV406 so that the reading on the digital voltmeter is

1.74 ± 0.04 V.

Adjustment Location: See page 12.

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect a digital voltmeter to TP516 on the MONITOR board.
3. Adjust RV408 so that the reading on the digital voltmeter is

2.09 ± 0.04 V.

Adjustment Location: See page 12.

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect an oscilloscope to TP508 on the MONITOR board.
3. Adjust RV411 so that the reading on the digital voltmeter is

2.47 ± 0.04 V.

Adjustment Location: See page 12.

10

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect an oscilloscope to TP405 on the MONITOR board.
3. Adjust RV408 so that the signal level in the 5th stage from the

top is the specified value A.
Specified value A: 1.90 ± 0.04 V
(Skip item 3 and start from item 4 when the value cannot be
completely adjusted.)

4. Adjust RV406 so that the signal level in the 1st stage from the

top is the specified value B.
Specified value B: 3.64 ± 0.02 V

5. Adjust RV407 so that the signal level in the 3rd stage from the

top is the specified value C.
Specified value C: 2.98 ± 0.02 V

6. Repeat items 3 to 5 and adjust the signal in the 5th, 1st and 3rd

stages.

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect an oscilloscope to TP405 on the MONITOR board.
3. Measure the black-to-black level.
4. Connect an oscilloscope to TP404 on the MONITOR board.
5. Adjust RV409 so that the black-to-black level A is the same as

the level measured in item 3.

6. Connect an oscilloscope to TP406 on the MONITOR board.
7. Adjust RV410 so that the black-to-black level is the same as the

level measured in item 3.

A

C

B

1st

3rd

5th

A

11

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale screen on the monitor screen.

2. Connect an oscilloscope to TP401 on the MONITOR board.
3. Adjust RV411 so that the level A of the output waveform is

6.88 ± 0.02 Vp-p.

Adjustment Location: See page 12.

Procedure:
1. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the gray scale on the monitor screen.

2. Connect an oscilloscope to TP401 on the MONITOR board.
3. Adjust RV412 so that the waveforms A and B meet the

specified value.
specified value A: 5.20 ± 0.04 V

B

: -1.68 ± 0.04 V

Adjustment Location: See page 12.

Procedure:
1. Set the input signal with no signal.
2. Press the TV/VIDEO button (S106) to the VIDEO mode.
3. Connect a frequency counter to TP16 on the MONITOR  board.
4. Adjust RV902 so that the reading on the frequency counter is

15.37 ± 0.02 kHz.

Adjustment Location: See page 12.

Procedure:
1. Input the mono scope signal from a NTSC pattern generator.
2. Press the TV/VIDEO button (S106) to the VIDEO mode,

display the mono scope on the monitor screen.

3. Adjust RV901 so that the mono scope is displayed in

symmetrical pattern on the monitor screen.

Adjustment Location: See page 12.

A

A

0V

B

12

RV410: B and R Level Adjustment 

RV409: B and R Level Adjustment 

RV407: RGB Gain,Bright2
             Adjustment 

RV201: 5V Adjustment 

RV412: VCOM Bias Adjustment 

RV411: VCOM,VCOM AMP Adjustment 

RV601: Inverter Voltage Adjustment 

RV902: Freerun
             Frequency
             Adjustment 

RV901: H CEN Adjustment 

RV405: GAMMA2 Adjustment 

RV406: GAMMA0,Bright2 Adjustment 

RV408: Bright1,2 
             Adjustment 

– MONITOR BOARD (SIDE A) –

TP22

– MONITOR BOARD (SIDE B) –

TP517

TP518

TP519

TP401

TP508

TP406

TP206

TP16

TP405

TP516

TP404