Date: 10/02/98 R762120
G2+DIAGNOSTIC
R762120
12
- Connect to the resistor R15 (side wire soldering J3) a precision
focus
probe.
CAUTION: read carefully all safety instructions, mentioned in the user's
manual of the precision focus probe.
- Switch on the projector.
- Adjust the potentiometer P1 for +1020V read out.
Ali1020V
Black balance
- Connect to the video input a colour bar signal.
- Proceed to
Random access adjustment mode
and highlight
color balance.
Press
ENTER
to display menu R10 (refer to owner's manual of the projector)
Use the arrow keys to select
black balance
and then press
ENTER
.
Adjust the "cut off" for each color for a bar scale level of 50.
- Adjust CONTRAST to minimum (number indication below the bar scale of 0) and
COLOUR until colour is off.
- Adjust BRIGHTNESS to mid-position (number indication below the bar scale of
50).
Proceed to the pre-adjustment of the black balance P2(B)-P3(G)-P4(R)
Observe the bars on the screen. If any trace of color appears on the black or
white bars then perform the following adjustments in low ambient light.
- Cover the blue and the red lens with the lenscap.
Short-circuit the two pins on the top
side of the respective colour driver,
see illustration.
Adjust the Green G-2 control P3 until
the green raster is just visible on the
screen.
Remove short-circuit
- Cover the green and the red lens with
the lenscap.
Colour driver
Short-circuit the two pins on the top side of the respective colour driver, see
illustration.
Adjust the Blue G-2 control P2 until the blue raster is just visible on the screen.
Remove short-circuit
- Cover the blue and the green lens with the lenscap.
Short-circuit the two pins on the top side of the respective colour driver, see
illustration.
Adjust the Red G-2 control P4 until the red raster is just visible on the screen.
Remove short-circuit
Remove the lenscaps
The raster on the screen should appear white.
short-circuit
Adjustment procedure
