Hitachi C43-FD8000, Service Manual

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32
SERVICE ADJUSTMENTS
2.4 BEAM ALIGNMENT
Preparation for adjustment
(1) Preheat 30 minutes or more before the adjustment.
(2) The static convergence data should be cleared.
(3) Raster inclination should be adjusted. Optical focus should be coarsely adjusted.
(4) Contrast should be set MAX and the other control should be set CENTER.
(5) Receive the NTSC cross-hatch pattern signal or dot pattern signal.
(6) Discharge static charge from metallic parts on PRT neck by using short-clip-jig.
Adjustment procedure
(1) Green (G) tube alignment: Short-circuit TS (2P EH) connectors on the red
( R ) and blue (B) CPT P.W.B.s and project the only green beam.
(2) Set the G tube beam alignment magnet to the cancel state as shown below.
(3) Turn the static focus VR*
1
for Green fully counterclockwise and check
the cross-hatch center position on the screen.
Note : Halo state
(4) Turn the static focus VR*
1
for Green fully clockwise.
(5) Turn 2 sheets of the alignment magnet in either direction and move the
cross-hatch center to the position where is checked in step (3).
(6) Turn the static focus VR*
1
for green and check if the picture position moves or not.
(7) Repeat steps (2) to (6) until the picture position does not move during step (6)
(8) In the same manner, adjust the red ( R )*
2
and the blue (B)*
3
tube alignments.
(9) Fix the beam alignment magnet with white paint after the alignment is completed.
*
1
*
2
Static Focus VR is on focus pack UFPK
*
3