Mitsubishi SL2U Service Manual page 14

Adjustment Procedures
[A/D Pre-Amplification Circuit]
1. ADC offset/gain
adjustment
Measuring
---
instrument
Test point ---
EXT trigger ---
Measurement
---
range
Input signal Shown in the table 1, 2
Input terminal COMPUTER IN terminal
Model
SL2U
XL2U
Table 1
No. Pattern
01 White Raster
Table 2
Adjustment purpose
Symptom when
incorrectly adjusted
* Enter the adjustment commands in capital alphanumeric letters.
1. Connect the projector with a personal computer running Microsoft
95/98/Me/XP operating system. (Refer to the figure on page 1.)
2. Start Microsoft
3. Start the communication program [Hyper Terminal] on Microsoft
95/98/Me/XP to open the Hyper Terminal window. (Refer to Hyper Terminal
Setting on page 2 for the settings.)
Offset adjustment with the RGB signal supplied
4. Supply an signal (White Raster, No. 01).
5. Enter [00 ~ AC0] (the command for RGB input clamp adjustment) on the Hyper
Signal
Terminal window, and the adjustment proceeds automatically.
SVGA 6. When the adjustment finishes, the return command [00 ~ AC0111] is displayed
XGA
on the Hyper Terminal window. The last three digits of the return command
indicate the adjustment results of R, G, and B respectively from the left by 1 or
0. When the adjustment has succeeded, 1 is displayed. When it has failed, 0
is displayed. Possible causes of failures in the adjustment are errors on the
PCBs, wrong signals, and wrong input selection.
Gain adjustment with the RGB signal supplied
7. Supply an signal (White Raster, No. 01).
8. Enter [00 ~ 5] (the command for A/D adjustment) on the Hyper Terminal window,
and the adjustment proceeds automatically.
9. When the adjustment finishes, the return command [00 ~ 5111] is displayed on
the Hyper Terminal window. The last three digits of the return command
indicate the adjustment results of R, G, and B respectively from the left by 1 or
0. When the adjustment has succeeded, 1 is displayed. When it has failed, 0
is displayed. Possible causes of failures in the adjustment are errors on the
PCBs, wrong signals, and wrong input selection.
To adjust the DC level and amplitude of the video signal at the time of
ADC input.
Solid black, solid white, or incorrect color phase appear in the projected
image.
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Windows 95/98/Me/XP.
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Windows
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Windows