Hitachi 50SBX78B Projection Television User Manual


 
2.5.4 Matrix surround/monaural check
Adjustment procedure
l
Check that the following waveforms are obtained.
(Input signal @ only)
l
Front: R and L waveforms are almost equal.
l
Rear: R and L waveforms are almost Zero.
FRONT
REAR
Note: Center has no output.
2.5.5 Hall surround check
Adjustment procedure
(1) Set to SURROUND: HALL.
(Input signal 0 and @ ).
l
Front: Check that the phases of R and L signals
are different and 400 Hz is superimposed
on 5kHz.
l
Rear: Check that the R and L are opposite and
400Hz is superimposed on 5kHz. The R
and L amplitudes are equal.
FRONT REAR
L
R
Note: Amplitude levels of front R and L are not
even depending on P.W.B. Center has no
output.
2.5.6 Hall surround/monaural check
Adjustment procedure
l
Check that the following waveforms are obtained.
(Input signal @ only)
l
Front: The phases of R and L are different.
The amplitudes are different.
l
Rear: The phases of R and L are opposite.
The amplitudes of R and L are equal.
FRONT
REAR
Note: The monaural check can be omitted.
Amplitude levels of front R and L are not
even depending on the P.W.B. Center has
no output.
2.5.7 Dolby surround check
Adjustment procedure
(1) Set to SURROUND: DOLBY-NORMAL
.
Check that the following waveforms are
obtained. (Input Signal @ and @ )
.
Front: 400 Hz is superimposed on 5kHz.
.
Rear: R and L are the same signal and 400Hz
is superimposed on 5kHz.
FRONT REAR
L
R
Note: MODE: PRO LOGIC (NORMAL)
2.5.8 Dolby surround/monaural check
Adjustment orocedure
(1)
.
.
.
.
Set
t0
SURROUND: DOLBY-NORMAL
Check that the following waveforms are
obtained.
(Input signal @ only).
Front: Almost no output from both R and L.
Center: Same as the audio input signal.
Rear: Almost no output from both R and L.
CENTER
FRONT REAR
2.6 Raster Inclination adjustment (Deflection yoke)
Adjustment preparation
(1)
I:;
(4)
(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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