CTX CMS-3435 - Side Pincushion Correction; Horizontal Size Adjustment; Video Circuit Fine Tuning

(4) Observe the picture to see if there is any fold
over on top or compression at the bottom of
the picture, adjust VR204 to obtain a normal
picture.
Readjust VR201 to obtained 187mm + 2mm
picture height.
(6) Receive CGA signal with cross hatch
pattern.
) Check picture height be 180mm + 3mm.
(8) Receive one of VGA signals (3850/400/480
lines).
(9) Turn the Auto Switch on the front panel to
ON position.
(10) Check picture height be the same 185mm
+3mm when changing among the 350/400
/480 lines different vertical resolution display
modes.
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2.8 Side Pincushion Correction
(1) Receive EGA signal with cross hatch
pattern.
(2) Adjust VR204 for best side Pincushion
correction.
(3) Receive VGA 400 lines and 480 lines signals
and check side pincushion correction, fine
tune VR204 if necessary to obtain best
correction.
(4) Receive 1024X768 signal with cross hatch
pattern.
(5) Adjust VR207 to obtain best side Pincushion
Correction.
2-9 Horizontal Size
(1) Receive VGA (400 lines) signal with cross
hatch pattern.
(2) Adjust L305 to obtain 250mm + 2mm
picture width.
3. Video Circuit
Prior to the video circuit adjustment, all sync and
deflection circuit adjustments must be completed,
the monitor must have been warmed up for more
than 30 minutes.
Video signal must have 75Q impedance and cor-
rect voltage at the monitor input terminal. Before
adjusting, make sure VR501, 502, 503, 214, 215,
216, 211, 212, and VR213 are preset to the me-
chanical center position.
3.1 Cut Off Adjustment
(1) Receive VGA (400 lines) signal with a blank
pattern (black).
(2) Turn the screen VR on the FBT counterclo-
ckwise to minimum, then turn it clockwise
until the background raster is just visible on
the screen.
(3) Adjust VR408 and VR410 to obtain a gray
blackground raster.
(4) Turn the screen VR counterclockwise to
the position that the blackground raster is
just diminished.
3.2 White Balance Adjustment
(1) Receive VGA (400 lines) signal with full
screen white pattern.
(2) Set user contrast control to its minimum
and bright control to its maximum.
(3) Adjust VR214, VR215, VR216 to read CIE
coordinate X= 0.281+ 0.015, Y= 0.311+
0.015 using Minolta Color Analyzer II.
(4) Set user contrast control and bright control
to their maximum.
(5) Adjust VR501, VR503 to read the same CIE
coordinate as step (3).
(6) Set user contrast control to its maximum
and bright control to its minimum.
(7) Check CIE coordinate be within + 0.015
limits, if not, fine tune VR214, VR215, VR216
for compensation.
(8) Adjust user contrast control to 20 ft-L and
check for CIE color coordinate, if it is not
right, go back to step (4).
3.3 Brightness Adjustment
(1) White balance must have been adjusted
prior to this adjustment.
(2) Receive VGA (400 lines) signal with stair
step pattern.
(3) Set user contrast and bright control at their
maximum.
(4) Adjust screen VR on FBT so that the first
step of the stair step signal can just be
seen.
(5) Receive same signal with 60 X 60mm white
pattern.
(6) Check brightness be within 55 ft-L through
70 ft-L.
4. Focus Adjustment
(1) Receive VGA (400 lines) signal.
(2) Set user contrast and bright control at their
maximum.
(3) Adjust focus control on the FBT so that
focus at the middle points between the cen-
ter of the screen and the four corners to its
best. This is to make the focus for the full
screen area even.