— 5 —
4. VCOM DC coarse adjustment
•
Conditions
(1) Apply 11.50
±
0.05 [V] on Vcc1-1.
(2) Signals:
provide color bar pattern (white 75 %) composite video signal from CP196.
Signal level; 1Vp-p
±
0.01V (75 ohm termination), conforming to NTSC-M system.
(3) Connect 47kohm resistor between CP304 and CP300 (GND).
•
Adjustment
(1) Adjust VR310 so that the amplitude of VCOM output (CP710) is 10.0
±
0.5 [V].
(2) Adjust VR703 so that High level of VCOM output (CP710) is 6.5
±
0.5 [V].
GND
6.5 V
10.0 V
VCC1-1
IF signal
Signal
generator
Stabilizer
M-PCB
B output
CP710
Oscilloscope
5.
LCM screen positioning
•
Conditions
(1) Apply 11.50
±
0.05 [V] on Vcc1-1.
(2 Signals:
Apply monoscope pattern composite video signal from CP196.
Signal level; 1Vp-p +/-0.01V (75 ohm terminated), conform to NTSC-M system.
•
Adjustment
(1) Connect LCM to display monoscope pattern.
(2) Adjust LCD’s H.POS to display the picture in the center.
Adjust so that the right and left patterns are the same.
•
Caution
(1) Non-equality of right and left pattern should be less than 1 mm.
(2) Adjustment should be done with the display unit which is assembly of LCM and PCB.
VCC1-1
IF signal
Signal
generator
Stabilizer
M-PCB
LCM
Signal
Backligjt
Right and left pattern balance
should be equal.
The difference between the
right and left pattern should be
less than 1mm.
