JVC AV-56WP74 Service Manual page 55

3.8.5 VIDEO ADJUSTMENT
Measuring
Item
instrument
A-D Signal
generator
CONVERTER
OFFSET
Remote
adjustment (1)
control unit
Upper side of screen
whole black
Fig. 1 <FULL screen>
Fig. 2 <SPLIT screen>
Test point Adjustment part
[1.PICTURE/SOUND]
F44 : Image
adjustment
F45 : Image
adjustment of mode
change
F47 : Minimum value
B at the time of
detection
F48 : Maximum value
A at the time of
detection
[8.PP]
ADM012 : R offset
AMD013 : G offset
AMD014 : B offset
To be slightly whitish
rather than whole black
Description
[WHITE BALANCE LOW LIGHT ADJUSTMENT for
SINGLE SCREEN]
(1) Input the 480i (DVD) whole black signal from the
COMPONENT VIDEO terminal.
(2) Select STANDARD mode with [VIDEO STATUS]
key.
(3) Select FULL mode with [ASPECT] key.
(4) Select 1.PICTURE / SOUND from SERVICE MENU.
(5) It goes into the zero mode screen of difference
adjustment of color, using <F44>(Image adjustment)
as 0 to 1, and using <F45>(Image adjustment mode
change) as 0 to 3.
(6) Set <F47> (minimum value B at the time of
detection) to 0 and <F48> (maximum value A at the
time of detection) to 0.
(7) Press [MUTING] key and memorize the set value.
(8) Press [BACK] key and display SERVICE MENU
screen again.
(9) Select 8. PP from SERVICE MENU.
(10) Adjust <ADM012> (R offset setup) and <ADM014>
(B offset setup) so that the adjustment result out put
screen in the upper half of a screen becomes black
color.(Fig.1)
(11) If the screen is reddish, adjust <ADM012>(R offset
setup) so that the redness is reduced to the
minimum.
(12) If the screen is bluish, adjust <ADM014>(B offset
setup) so that the blue is reduced to the minimum.
(13) Press [MUTING] key and memorize the set value.
[BRIGHTNESS ADJUSTMENT
SCREEN]
(1) Select STANDARD mode with [VIDEO STATUS]
key.
(2) Select FULL mode with [ASPECT] key.
(3) Press [SPLIT] key to enter the SPLIT screen mode,
then input gray scale signal on both left and right
channels.
(4) Select 1.PICTURE/SOUND from SERVICE MENU.
(5) It goes into the Y adjustment MAX mode, using
<F45> as 0 and using <F44> as 0 to 1.
(6) Set <F47> to 16 and <F48> to 16.
(7) Press [MUTING] key and memorize the set value.
(8) Press [BACK] key and display the SERVICE MENU.
(9) Select 8. PP from SERVICE MENU.
(10) Adjust <ADM013> (G offset setup) so that the
screen on the right upper side becomes slightly
whitish rather (6% black) than whole black.(Fig.2)
(11) Press [MUTING] key and memorize the set value.
AV-48WP74
AV-56WP74
for SPLIT RIGHT
(No.52105)1-55