Nokia 445PRO, Руководство по обслуживанию, Страница: 32 / 67

445N
30
7.4. Grey Scale
The grey scale is adjusted for 9300K colour temperature.
Activate Service Mode in 107.10 kHz/85Hz (NCE791).
7.4.1. The Most Dominant Colour
The most dominant colour has been marked in a label on the deflection yoke.
It may not be correct if tube or SMH card has been changed. In that case judge
the most dominant colour from the tone of the picture after you have made the
following adjustments.
1) Select
107.10/85.0
(NCE791) black test pattern.
2) Set to maximum and to minimum.
3) Set Blacklevel adjustment RED/GREEN/BLUE Black Level to (step 25)
4) Set
RED/GREEN/BLUE Amp
menu and
G2 menu
adjustments to center
(step130).
5) Place the probe of the colour analyzer in the middle of the screen and
adjust with
G2 trimmer
until the picture illuminance is 3±1.0 cd/m
2
7.4.2. Low Light
1) Select 107.10/85.0 (NCE791) black test pattern.
2) Adjust picture illuminance to 1.0 cd/m
2
with potentiometer.
3) Adjust the with potentiometer to the minimum.
4) Adjust the colour coordinates to (9300K)
x = 0.283±0.010
y = 0.297±0.010
with RED/GREEN/BLUE Black Level adjustments.
Do not adjust the most dominant colour.
During the adjustment check if brightness is chancing over tolerance, when
needed adjust it back. If Y--- and X---values are getting too far from ideal val-
ues, you have chosen wrong MOST DOMINANT COLOUR. Check the domi-
nant colour again according to the instructions.
5) Set to the maximum and check that the illuminance is still 3±1.0 cdm
-- 2
.
If not, repeat 7.4.1. steps 5).
6) Adjust picture illuminance to 1.0 cd/m
2
with potentiometer and check the
colour coordinates.
7.4.3. High Light
1) Select 107.10/85.0 (NCE791) black test pattern.
2) Adjust with the picture illuminance to 1±0.1 cd/m
2
.
3) Select 107.10/85.0 (NCE791) window test pattern.
4) Adjust with the picture illuminance in the window to 100±5 cd/m
2
5) Adjust with
RED/BLUE Amp
the colour coordinates in the window to
x = 0.283±0.003
y = 0.297±0.003
Check after adjustment that the illuminance reading is in limits.
7.5. Maximum/Minimum Contrast
1) Set to the maximum.
2) Adjust with the picture illuminance outside window to 1.0 cd/m
2
.
3) Adjust illuminance in the window to 140±5 cd/m2 with
MAX CONTRAST .
4) Set to the minimum.
5) Adjust the minimum illuminance in the window to 5 ± 1 cd/m
2
with
MIN CONTRAST .
6) Exit from service mode.
7.6. Focus
1) Select 107.10/85.0 (NCE791) crosshatch test pattern
2) Set to the maximum and adjust to 70 % (background faintly visible).
3) Adjust the sharpness with FOCUS H and FOCUS V to optimum
4) Adjust until the background is invisible
5) Select focus test pattern. Check that all letters are clearly visible.
FOCUS H
Left side view
of the chassis
FOCUS V
G2
pixelpixelpi
pixelpixelpi
pixelpixelpi
pixelpixelpi