Samsung SP403JHAX, Service Manual

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Alignment and Adjustments
5-8 Samsung Electronics
5-6-1 LCD Control Board PLL Adjustment
1. Input a color bar signal.
2. Connect CNL06,RPD to an oscilloscope, and
check the waveforms.
(1 V/div, 20 u sec/div)
5-6-2 Matrix IC (TDA4780) Sub Tint Adjustment
1. Input a color bar signal.
2. Connect CNL07 (B output) to an oscilloscope,
and check the waveform.
(0.5 V/div, 20 u sec/div)
5-6-3 Matrix R Output Signal Amplitude
Adjustment (Red Drive)
1. Input a 10-step signal (Color OFF).
2. Connect CNL07 (R output) to an oscilloscope,
and check the waveform.
(0.5 V/div, 10 u sec/div)
3. Adjust the red drive so that the signal ampli-
tude becomes 0.7Vp-p.
4. Adjust the Sub-brightness of TDA4780 so that
the waveform (without sync) is seen as shown
in the figure below.
5-6-4 Matrix G Output Signal Amplitude
Adjustment (Green Drive)
1. Input a 10-step signal (Color OFF).
2. Connect CNL07 (G output) to an oscilloscope,
and check the waveform.
(0.5 V/div, 10 u sec/div)
3. Adjust the green drive so that the signal
amplitude becomes 0.7Vp-p.
5-6- 5 Matrix B Output Signal Amplitude
Adjustment (Blue Drive)
1. Input a 10-step signal (Color OFF).
2. Connect CNL07 (B output) to an oscilloscope,
and check the waveform.
(0.5 V/div, 10 u sec/div)
3. Adjust the blue drive so that the signal ampli-
tude becomes 0.7Vp-p.
5-6-6 Main Brightness Adjustment
1. Input a 10-step signal (Color OFF).
2. Connect LCD CNL08(R1) input to an oscillo-
scope, and check the waveform.
(2 V/div, 10 u sec/div)
3. Adjust the main brightness so that the Ref
pulse is positioned on the center of signal.
Note : The change point (on gamma curve) is
determined by Ref.
RPD
DC2.8V
5-6 Circuit Adjustments
Sync
REF Pulse