White Balance Adjustment (1); White Balance Adjustment (2) - Hitachi 36SDX88B Service Manual

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3.4 White balance
adjustment (I)
Adj. point
Preparation for adjustment Adjustment procedure
Notes
(I) 20 minutes heat-run is (I) Turn screen adjustment VR clockwise Adjustment criteria :
necessary before
gradually until horizontal line appears more than 0.5V with cathode
adjustment. slightly on the surface of CPT. voltage conversion
No longer change the data of color,
data A, which appears the first.
(2) The surface of CPT should (2) Adjust white balance so that equally Adjustment criteria :
be less than 20 lux.
RGB lines appear slightly in low light less than 0.5V with cathode
voltage conversion
(3) Check if the value of sub- (3) Release stopping vertical deflection. Adjustment No.
black level center is 64 at
PO5 R cut OFF
adjustment No.PlO. PO6 G cut OFF
PO7 B cut OFF
(4) Receive white raster. (4) Set contrast minimum, then set sub- QC should guide suitably the
TV Mode brightness so that white raster appears people who is in charge
slightly. of this adjustment so that
white balance tolerance
is minimum after heat-
(5) Turn screen VR, which is (5) Set white balance meter at the center Lowl;;$nht(lO-15cd/n?)
near FBT, full of the picture.
counterclockwise.
(6) Send IIC data so as to (6) Adjust white balance after calibrating Adjustment No.
stop vertical deflection. brightness so that the level of white PO'l R Drive
balance meter is 80% of full scale. PO2 B Drive
(7) Check if white balance is correct in low Do not use mirrors during
light with changing brightness by eyes. Adjustment No.
Adjust white balance at low light PO5 R cut OFF
except for data A if white balance is PO6 G cut OFF
incorrect, then return to adjustment PO7 B cut OFF
process 7.
White balance :9300" K
3.4 White balance adjustment (2) Adj. point
Preparation for adjustment Adjustment procedure Notes
(I) Receive 100% white signal (1) Copy data at PO1 to P17, then add 4
of VGA3. to P'l7. Copy data at PO2 to Pj8.
(2) Set brightness to the (2) Confirm color temperature.
center, and contrast to the Adjust color temperature by
Maximum. adjustment code PI7 and P18, if it
does not satisfy specification of 9300K;
X=0.285, Y=O.294.
(3) Set color temperature to
9300K mode.
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