XOCECO LC23K6, Service Manual

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offset_R, offset_G,offset_B, gain_R and gain_G, repeatedly using the same method until the value
of the two levels gray-scale be the specified value.
3.4 white balance adjustment YPbPr channel
input YpbPr signal of K-7253 to YPbPr-1 terminal, input TIME380(480i) PATTERN471 8 level
gray-scale signal, set the value of S-bright to 120 and S-contrast to 140.Enter adjustment menu of
white balance, adjust the third level using white balancer. Adjust offset_R, offset_G and offset_B, to
let color coordinate of the third level be 285 and 290 and its brightness be about 12.5nit.
Input 8 level gray-scale signal of TIME392(480p), TIME394(720p) and TIME396(1080i) separately,
repeat the above operations to let color coordinate of the third level be 285 and 290 and its
brightness be about 12.5nit.
4 Performance check
4.1 TV function
Enter searching menu
→ auto search, connect RF-TV terminal with central signal source and check
if there are channels be skipped
4.2 AV/S, YpbPr terminals
Input AV/S, HD signal, check if it is normal.
4.3 VGA terminal
Insert VGA terminal, input VGA format signal of 640 X 480@60 Hz, check if the display is normal. If
interference exists, press the auto adjust button on remote control again and check if it is normal.
4.4 DVI terminal
Insert DVI terminal, input signal of 640 X 480@60 Hz signal and check if the display is normal.
4.5 check sound channel
Check the speaker and headphone of each channel.
4.6 presetting before ex-factory
Trouble shooting
Before servicing please check to find the possible causes of the troubles according to the table
below.
1.Antenna(signal):
Picture is out of focus or jumping Bad status in signal receiving
Poor signal
Check if there are failures with the electrical connector or
the antenna.
Check if the antenna is properly connected.
item setting item setting item setting
Picture mode NATURE OSD language English BALANCE 50
Sound mode NEWS VGA color
temperature
12000 SRS OFF
N/R WEAK SPEAKER ON CCD OFF
SCREEN 16:9 HEAD PHONE ON Turn off TV