Philips S42SD-YD09 Service Manual page 74

EN 74 8. SDI PDP 2K6
8.3 Waveform Alignments 42" HD w1
1. Set the pattern to Full White:
• Place jumpers on:
– J8902 of the PSU alarm board
– J5003 and J5004 of the PSU
– Pins 1 and 2 of CN2072 on the Logic Board
• When the display starts showing a cycle of different
patterns, push button SW2001 for at least one second.
Now the display shows a continuous full white pattern.
To restart the cycle of different patterns, push the
button once more and wait for a few seconds.
2. Check the waveform using an Oscilloscope.
• Triggering through V_TOGG of the LOGIC Board (see
Figure "Logic PWB").
Alignments
Figure 8-18 Adjusting procedure - 42" HD w1
Jumper
Push button
Figure 8-19 Logic PWB - 42 HD w1
• Connect the "OUT240" test point, located at the centre
of the Y-buffer PWB, to the other channel, and then
check the first Subfield waveform of one TV-Field.
• Check the waveform by adjusting the Horizontal
Division of the oscilloscope.
• Check the waveform by adjusting the Horizontal
Division of the oscilloscope.
• Check the Reset waveform when the V_TOGG level is
changed.
3. Adjust the waveform of the rising ramp with VR5001 (see
Figure "Rising ramp waveform adjustment").
4. Adjust the waveform of the falling ramp with VR5002 (see
Figure "Falling ramp waveform adjustment").
VR5001 Adjustment : Rising Ramp
Oscilloscope Setting : 50V / 40us
VR5002 Adjustment : Falling Ramp
Oscilloscope Setting : 50V / 40us
G_16380_410.eps
Vtogg
G_16380_405.eps
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