Electrical Adjustments; Monitor Section - Sony XTL-W70 Service Manual

MONITOR SECTION

Equipment Used
The measuring equipment below are used for these electrical
adjustments:
• Oscilloscope
• NTSC pattern generator
• Regulated DC power supply
• Digital voltmeter
Connection of Equipment
Unless otherwise specified, the measuring equipment should be
connected as shown below:
INPUT (1)
(VIDEO)
NTSC pattern
Tuner unit
generator
XT-992V
VIDEO OUT
(75 Ω )
Parking
Setup for Adjustment
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.
Setup to switch position:
DIMMER switch (S801) ...................................................... HIGH
5V Adjustment
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.
SECTION 3

ELECTRICAL ADJUSTMENTS

MONITOR OUT
Monitor
XVM-W71
Regulated DC
power supply
ACC cord
+
–
white
0.74Vp-p
black
Inverter Voltage Adjustment
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 2 Adjustment
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.
RGB Gain Adjustment
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 0 Adjustment
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.
Bright Adjustment (1)
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.
VCOM Adjustment
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.
XTL-W70
9