Video Board (2/2) - Panasonic WE-MV180A Service Manual

(21) Luminance Gain Adjustment
Test Point: TP5 (APL)
Adjust: VR3 (APLG)
8
Connect the Digital Voltmeter to TP5.
8
Set the Positive mode by pressing the Nega Button.
8
Adjust VR3 to obtain 2.0 ± 0.1 V DC.
An adjustment should be made with the Positive mode
and Negative mode by pressing the Nega Button
alternately.
(22) Hue Level Adjustment
Test Point: TP3 (HUELVL)
Adjust: VR1 (HUE)
8
Connect the Video Monitor to the Composite Video Output
Connector.
8
Connect the RGB Video Monitor to the RGB Video Output
Connectors.
8
Set the Positive mode by pressing the Nega Button.
8
Adjust VR1 so that the colour of the RGB Video Monitor
becomes same colour of the Composite Video Monitor.
An adjustment should be made with the Positive mode
and Negative mode by pressing the Nega Button
alternately.
(23) Chroma Gain Adjustment
Test Point: TP8 (R)
TP9 (G)
TP10 (B)
Adjust: VR4 (CGA)
8
Connect CH1 of the Oscilloscope to TP8, CH2 to TP9 and
CH3 to TP10.
8
Trigger the Oscilloscope at TP7.
8
Trace the Oscilloscope by 2H.
8
Set the Positive mode by pressing the Nega Button.
8
Adjust VR4 so that the Blue signal is stable as shown in
Fig. 4-20.
An adjustment should be made the Positive mode and
Negative mode by pressing the Nega Button alternately.
R
G
B
No Good
Fig. 4-20
RGB Board
RGB Board
RGB Board
RGB Board
RGB Board
RGB Board
RGB Board
RGB Board
R
G
B
Good
5. CHECK OUT PROCEDURE
8
In this section describe the Camera Unit and the LCD
Monitor Ass'y check out procedure for easy to find out
defective point.
Check for the LCD Monitor Ass'y
8
Referring to Fig. 5-1, remove four screws that secure the
LCD Rear Cover and remove the LCD Rear Cover.
LCD Rear Cover
8
Connect the Digital Voltmeter between Red wire and
White wire as shown in Fig. 5-2.
8
Confirm that + 7.5 V DC is supplied or not.
If + 7.5 V DC is not supplied, connect the Digital Voltmeter
between pins 1 and 2 of CN2 on the Video Board.
8
Confirm that + 7.5 V DC is output to the LCD Monitor
Ass'y or not.
If + 7.5 V DC is output, the Wire between CN2 on the
Video Board and the LCD Monitor Ass'y is defect.
8
Connect the Oscilloscope between Yellow wire and White
wire as shown in Fig. 5-2.
8
Confirm that the Composite Video signal as shown in Fig.
5-3 is supplied or not.
11
Remove four screws.
Fig. 5-1
White (GND)
Red (+7.5V)
Yellow (LCD)
Fig. 5-2