Service manual

30
ViewSonic Corporation Confidential - Do Not Copy PJ513D-1
1. EE Assembly and Alignment Concern:
1. Color Wheel Delay Alignment
Equipment:
- Battery Biased Silicon PIN Detector
- Oscilloscope
- Probe
OSD Default value:
Item Value Item Value
DLP Brightness 32 CW Delay Adjustable
DLP Contrast 32
White Peak 10
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 “Æ” and “Å” key to increment or decrement the color wheel delay value
No matter the waveform is square or not, let the waveform was lagged first
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 854*480@60Hz
(480P)
(1) General-1 pattern. (Pattern 1)
(2) 32 grays pattern. (Pattern 48)
(3) White pattern. (Pattern 41)
Lag
Exact Ahead