ViewSonic PJ513D-1 Service Manual page 33

1. EE Assembly and Alignment Concern:
1. Color Wheel Delay Alignment
Equipment:
Battery Biased Silicon PIN Detector
-
Oscilloscope
-
Probe
-
OSD Default value:
Item
DLP Brightness
DLP Contrast
White Peak
The default values let optical engine to get maximum contrast and brightness.
Procedure:
Probe impedance matches 50 ohm
Open Factory OSD, and select color wheel delay item
Leave the image pure red (DMD red curtain)
Put the detector on the screen that red image was projected.
Watch the oscilloscope and notice the square waveform
Use the " " and " " key to increment or decrement the color wheel delay value
No matter the waveform is square or not, let the waveform was lagged first
Lag
Then increment or decrement the value to let the waveform to be square
Do not adjust too much, let the signal get ahead, if it happens, go back to step 7 and do it again.
Change the input to pure blue and repeat the above procedures again.
Change the input to pure green and repeat the above procedures again.
2. Main board check procedure
Equipment:
Pattern generator
-
Procedure:
1. Connect power, D-sub into projector.
2. Light on projector.
3. Testing below patterns and resolution is
(1) General-1 pattern. (Pattern 1)
(2) 32 grays pattern. (Pattern 48)
(3) White pattern. (Pattern 41)
ViewSonic Corporation
Value Item
32 CW Delay
32
10
Exact
854*480@60Hz
30
Value
Adjustable
Ahead
(480P)
Confidential - Do Not Copy
PJ513D-1