6
4.5 Sound inspection
4.5.1
Receive 1kHz sound signal 100% modulated and connect X701 with 8
Ω
false resistances
(load). Connect sound voltage meter and Oscillograph to two poles of the false resistances.
4.5.2
Turn the sound to the biggest volume. Balance the sound and set the high/low sound to the
middle, MSS OFF, DBE OFF, and the sound power should be
≥
7 W
×
2
(
about 7.5 Vrms
)
,
distortion
≤
7% (A slight peak cutting at maximum sound sine wave is allowed.
)
4.6 Alignment of focus potentiometer
4.6.1
Pre-warm the TV set for 30 minutes.
4.6.2
Receive the signal from testing card.
4.6.3
Push the key of picture mode to place analog in “dynamic”.
4.6.4
Adjust potentiometer of FOCUS on the FBT to make the picture to be best focused.
4.7 Alignment of line center
4.7.1
Receive 50 HZ signal from video head.
4.7.2
Enter the factory menu RGB HOR. POSITION item under AV status, adjust amplitude of RGB,
and make the picture to be symmetry. Then save.
4.7.3
Receive 60Hz video signal and enter the factory menu RGB HOR.POSITION item under AV
status. The adjusting method of POSITION is same as 4.7.1
~
4.7.2.
4.7.4
Adjust separately under following four modes
a
)
50 Hz 4: 3;
b
)
60 Hz 4: 3;
Of which Vert position is unnecessary for readjustment after setup at the initial value. Adjust
the value of R378 to optimize it (set it up during the production in the factory).
4.8 Field amplitude, field S alignment, field center, line amplitude, E/W alignment etc.
Enter the corresponding item of factory menu and adjust the geometric distortion until accepted.
Hor Amplitude
Cushion
Trapeze
Angle
Bow
Hor Symmetry
Hor Corners
Vert position
Vert Amplitude
Vert S-Correction
Vert S-Symmetry