XOCECO LC27K6, Service Manual

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5
density are all set to regulated value.
2.2.4 White balance adjustment of YprPb channel
Input YPbPr signal of K-7253 to D4-1 terminal,input eight grades of grey density signal of
TIME380(480i)PATTERN471, adjust S-bright to be 120,S-contrast to be 140. Enter the adjustment menu
of white balance,adjust second grade with balancer. Adjust offset_R, offset_G, offset_B sot that the
second grade color coordinates are 255,240 and the brightness about 3.5 nit.
Separately input eight grades of grey density signal of mode TIME392(480p),TIME394(720p)and
TIME396(1080i). Repeat the above operation, so that the second grade color coordinates are 255,240
and the brightness about 3.5 nit.
3. Function inspection
3.1 TV function
Enter the search menu
→
auto search, connect RF-TV terminal to the central signal source, check if
there is station skipping.
3.2 AV/S, HDTV terminal
Connect AV/S and HDTV signal, check if they are normal.
3.3 VGA connector
Insert VGA signal connector, input format signal 640 x 480@60 Hz VGA, check if the display is
normal. If there is interfere in picture, push the adjustment key on the remote control set one more time,
check if the display is normal.
3.4 Sound channel inspection
Check if the output of each speaker and earphone channel is normal.
3.5 For factory preset, see table. 1
Trouble shooting
Before servicing please check to find the possible causes of the troubles according to the table below.
1.Antenna:
Picture is out of focus or jumping Bad status in signal receiving
Maybe broadcast signal itself is not good
Check if the outdoor antenna is disconnected.
Check if the antenna is correctly oriented.
Fringe in picture Check if the antenna is correctly oriented.
Maybe there is electric wave reflected from hilltop or building.
Picture is interfered by stripe
shaped bright spots
Possibly due to interference from automobile, train, high
voltage transmission line, neon lamp etc.
Maybe there is interference between antenna and power
supply line. Please try to separate them in a longer distance.
There appear streaks or light color
on the screen Check if interfered by other equipment and if interfered
possibly by the equipment like transmitting antenna, non
professional radio station and cellular phone.