Static Focus Adjustment; Blue Defocus Adjustment; Digital Convergence Adjustment - Hitachi 50gx49b Service Manual

PRT SURFACE SIDE
ALIGNMENT
ZERO FIELD
SPACER IN0
ADJUSTMENT)
MAGNET
TRUE CIRCLE SPECIFICATION
'ION
TRUE CIRCLE DEGREE: a/b
SPECIFICATION: 0.9-l .l
2.12 Static focus adjustment
Adjustment preparation
(1)
(2)
(3)
(4)
(5)
The raster. inclination, centering, horizontal/
vertical amplitude and optical/electrical focus
beam alignment should have been adjusted.
The static convergence data should be cleared.
Set video conditions to factory reset.
Receive the cross-hatch pattern signal.
Apply covers to the lenses of colors other than
the color to be adjusted and project a single
color.
Adjustment procedure
(1)
(2)
Red (Rj, Green (G) and Blue (B) static focus
adjustment. Vary the static focus VR (focus pack
UFPK) and make the center of the cross-hatch
pattern clearest.
Observe the corners of the picture and check
that the focus does not get conspicuously worse.
OBSERVING POINTS OF THE
CORNER OF THE PICTURE
OBSERVING POINTS
2.13 Blue defocus adjustment
Adjustment Preparation
(1) Optical and electrical focus adjustment should
have been completed.
(2) The convergence adjustment should have been
completed.
(3) Set Video conditions to factory reset.
Adjustment procedure
(I) Input an all-white signal shown below to VIDEO
input.
(2) Short-circuit 2P sub-mini connectors on the red
and green CPT P.W.Bs. to display only the blue
(3) Turn the
B
Focus VR (Focus Pack) fully clockwise.
(4) Measure the brightness at the center of the
screen and turn the B FOCUS VR (Focus Pack)
counterclockwise to adjust the brightness of blue
as shown in Table.
(5) After the adjustment is completed, if blue
exceeds the specification, turn and adjust focus
so that the sticking out part of blue satisfies the
specification.
~rw'~Y-4~~~~~~~ OUT OF BLUE
6-l IF/
Defocus stickina out specification
I
Screen Size 1 Blue sticking out 1
I
50"
I
1 .Omm
I
Condition: User controls are set to the initial set
Cautions:
positions (for shipment) Measuring point
Screen center.
Correct the brightness gauge and amplitude
of the all-white signal periodically. The
aperture angle of the brightness gauge is 1".
Use a cross-hatch pattern to check.
2.14 Digital convergence adjustment
Adjustment preparation
Receive an RF or video signal.
Set controls to factory preset.
Install jig screen on the set.
Note the center of the video pattern displayed.
This is necessary to match dotted lines
(adjustment point viewed) and actual point that
is adjusted and displayed by the video signal.