Hitachi 50SBX78B Projection Television User Manual


 
2. FINAL ASSEMBLY ADJUSTMENT
2.1 Focus adjustment
Adiustment preparation
(1)
(2)
(3)
(4)
The set can face in any direction: west, east,
north or south.
Receive the cross-hatch pattern signal.
CONTRAST : HALF
BRIGHTNESS : MINIMUM
The electrical focus adjustment should have
been completed.
The centering DY inclination should have been
adjusted.
Adjustment procedure
(1)
(2)
(3)
(4)
(5)
Loosen-the fixing screw on the lens cylinder so
that the lens cylinder can be turned. (Be careful
not to loosen too much. If it is loosened too
much, rattling when tightening becomes greater
and the focus may drift). After completing steps
(5), (6) and (7) below, tighten the fixing screws
for each lens with a torque of 12-17 Kgf cm.
Apply covers to 2 of R, G and B lenses, and
project a single color on the screen and adjust in
sequence.
(The adjustment order of R, G and B is only an
example.)
For each of the R, G and B lenses, observe the
color abberation generated on the outer
circumference of the cross-hatch bright line at
the center section +3 pitches vertically and
horizontally from the center.
If the lens adjustment knob is turned clockwise,
viewed from the front, the color aberration
changes as follows.
In case of G lens, set to the point where the
chromatic aberration switches from blue to red. If
the chromatic aberration appearing all over the
screen is not the same, observe the vertical
bright line at the center of the screen and set to
the position where red chromatic aberration
slightly appears inside and blue outside
(reference value: l -3mm) within the cross-hatch
pitches specified in next table. When the red
chromatic aberration appearing at both sides of
the bright line is not equal, observe the side with
larger chromatic aberration when adjusting.
RED
CHROMATIC
ABERRATION
Set Size Pitch between Ll & L2
50”
3.0 cross-hatch pitches
60”
3.0 cross-hatch pitches
63)
In case of R lens, set to the position where the
chromatic aberration changes from red to
crimson. As shown below, observe the vertical
bright line at the center and set to the position
where the crimson chromatic aberration slightly
appears inside and red outside (reference value:
1-3mm) within the cross-hatch pitches specified
in next table.
RED
CHROMATIC
ABERRATION
SLIGHTLY CRIMSON
CHROMATIC ABERRATION
{I
(7) In case of B lens, set to the position where the
chromatic aberration changes from purple to
green. As shown below, observe the vertical
bright line at the center and set to the position
where green chromatic aberration slightly
appears inside and purple outside (reference
value: l-3mm) within the cross-hatch pitches
specified in next table.
PURPLE CHROMATIC SLIGHTLY GREEN
ABERRATION CHROMATIC ABERRATION
I I
Set Size Pitch between L
I
50”
60”
3.0 cross-hatch pitches
3.0 cross-hatch pitches
SLIGHTLY BLUE CH6OMATlC ABERRATION
OR NO COLOR
25