Sub Picture White Balance Adjustment; Sp Matrix Check; Raster Inclination Adjustment (Deflection Yoke) - Hitachi 50gx49b Service Manual

2.4 Sub picture white balance adjustment
(ROM4, ROM6, ROM8)
Adjustment preparation
(1)
(2)
(3)
(4)
Start adjustment after power is ON for 20
minutes.
Use a white raster signal for adjustment.
Press "FREEZE" on the remote control and
select "SINGLE" freeze mode to display the sub
picture.
Set CONTRAST to Maximum, Other conditions
to center.
Adjustment procedure
(1) Connect oscilloscope to P802 and adjust ROM8
to match blue level of main and sub pictures.
(2) Repeat for P832 and ROM6 Green, P862 and
ROM4 for Red.
IV
K w
Note: If the sub picture has a signal sag, adjust level at
center point.
IV
MRllcN SAG
'I
4 . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . _ . . . .
9
ENlER P0lN-l
2.5 SP Matrix Check
Adjustment preparation
(1) Input the following audio signals to the audio
input of the VIDEO INPUT terminals, when
checking SP Matrix:
0
R ch: 435mVrms
@ L ch: no signal
.
Set the AUDIO ADVANCED SETTING for INT.
SPEAKERS: ON, LOUDNESS: OFF and
PERFECT VOLUME: OFF.
.
Set the volume control of FRONT to 20 step.
l
Set the BALANCE, TREBLE and BASS to
Normal.
Note: Front waveform: front speaker output of
the set.
Adjustment procedure
(1) Check that the waveforms shown below are
obtained (Input signal @ and a), at rear SP
Terminal Out.
(a) SP MATRIX mode
RR
RL
(b) EXT mode
RR
RL
-a I VPP
0
no signal
2.6 Raster Inclination adjustment (Deflection Yoke)
Adjustment preparation
(1)
(2)
I:;
(5)
(6)
(7)
The set'can face east or west.
Input the single cross test signal.
Set video conditions to factory reset.
The lens focus adjustment should have been
completed.
The electric focus should have been coarse
adjusted.
The digital convergence RAM should be cleared
(uncorrected state). With the TV set off, press
and hold the service switch located on the
Power/Deflection PWB and then press the
power button.
Start adjustment 20 minutes or more after TV is
turned on.
Adjustment procedure
(1) Apply covers to the R and B lenses and project
only green light.
(2) Turn the G deflection yoke and adjust the vertical
raster inclination.
(3) Then, remove the cover of R or B lens and project
red or blue light and green light together on the
screen.
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