Sharp XG-V10WU Service Manual page 57

TROUBLE SHOOTING TABLE FOR PC I/F UNIT-9
Checking the VIDEO input
Feed the composite video
signal to INPUT4 or INPUT 5.
Using panel key or remote
controller, select INPUT4 or
INPUT5.
Select the VIDEO signal type
on user menu.
5
Does image appear onscreen?
Yes
Is the image free of distortion?
Yes
Are the colors as specified?
Yes
No problem with the VIDEO
input.
Measure the following outputs on
oscilloscope screen: at pin (5)(R)
of IC324, pin (3)(G) of IC326 and
pin (5)(B) of IC326.
Is the video signal level
between VRB and VRT?
No
Measure the output at pin (5) or
(6) of IC323 on oscilloscope
screen.
Is the clamp pulse as
specified?
No
Check the VIDEO sync signal.
CVIC_IC or its peripherals
defective.
No
No
Check the VIDEO sync signal.
No
» VRB: Bottom reference voltage at video ADC
Yes
» VRT: Top reference voltage at video ADC
IC310 or CVIC_IC defective.
» Checking the clamp pulse
Yes
Clamp level setting IC (IC316,
IC327 or IC323) or its
peripherals defective.
57
XG-V10WU
AN-SD1U/S422U
Check the VIDEO sync signal.
Carry out the process
adjustment.
5