BenQ PB8250 - XGA DLP Projector, Service Manual

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Probe
Procedure:
(1) Probe impedance matches 50 ohm
(2) Open Factory OSD, and select color wheel delay item
(3) Leave the image pure red (DMD red curtain)
(4) Put the detector on the screen that red image was projected.
(5) Watch the oscilloscope and notice the square waveform
(6) Use the “
Æ
” and “
Å
” key to increment or decrement the color wheel delay value
(7) No matter the waveform is square or not, let the waveform was lagged first
(8) Then increment or decrement the value to let the waveform to be square
(9) Do not adjust too much, let the signal get ahead, if it happens, go back to step 7 and do it
again.
(10) Change the input to pure blue and repeat the above procedures again.
Ahead Exact
Lag
3. PC Color Alignment Procedure
Equipment:
-
Pattern generator
Procedure:
(1) Connect power, D-sub, into projector.
(2) Change pattern generator to pattern 47 (16 gray bar).
(3) Light on projector
(4) Enter factory mode.
(5) Choose ADC Brightness item to Press.
(6) Choose ADC Contrast item to Press.
(7) Change pattern generator to pattern 32 gray bar.
(8) See if any gray level was abnormal, if the abnormality happened, went back to step 4 and
then redid it again.
(9) Quit factory mode, after above adjustments finished.
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