BenQ PB8220 - XGA DLP Projector, Service Manual

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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.
11. Change the input to pure green and repeat the above procedures again.
3. Formatter 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
1024*768@60Hz (XGA); 800*600@60Hz (SVGA)
(1) General-1 pattern. (Pattern 1)
(2) 32 grays pattern. (Pattern 48)
(3) White pattern. (Pattern 41)
(4) SMPTE pattern. (Pattern 5)
4. The formatter board would be note fail if above three image-quality is not good.
5. Test the connection between formatter board to keypad board and IR board.
6. The formatter board would be note fail if there are some wires is broken in formatter board.
4. DMD Panel Alignment
Equipment:
- Pattern Generator
Procedure:
1. Connect power, Video signal into projector.
2. Light on projector
3. Change pattern generator to full white pattern.
4. Watch the image if any pixel lost
5. Change pattern to full black.
6. Watch the image if any pixel lost
7. Change pattern from full black to full white.
8. Watch the image if any pixel can not return
9. Change pattern from full black to full white.
10. Watch the image if any pixel can not return
11. If above 8 step has some pixel lost or can not return, it’s DMD chip has pixel defect
12. Change to the Slid Line pattern
13. Watch the image if any pixel lost
14. If above step has some pixel lost, it’s conductive rubber has defect or assembly loosed.
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