White Balance Adjustment - Symphonic ST413E Service Manual

8. Cut-off Adjustment
Purpose: To adjust the beam current of R, G, B, and
screen voltage.
Symptom of Misadjustment: White color may be
reddish, greenish or bluish.
Adj. Point Mode
Screen Control,
CH o / p buttons
M. EQ.
Pattern Generator See Reference Notes below.
Figure
PATTERN GENERATOR
EXT. INPUT
Note: Screen Control FBT --- Main CBA
FBT= Fly Back Transformer
Use service remote control unit
1. Degauss the CRT and allow CRT to operate for 20
minutes before starting the alignment.
2. Input the Black Raster Signal from RF Input.
3. Enter the Service mode. (See page 5-1)
4. Press "VOL p" button on the service remote control
unit and select "C/D" mode. (Display will change
"C/D," "7F," "LANGUAGE," "ACCESS CODE,"
"SOUND TYPE," "VIDEO TONE," "FM-MODE," "V-
OUT," "VIDEO," "AV-MEMO," "STABLE," "FIL-
TER," "YUVMEMORY" and "A-MUTE POL" cycli-
cally when "VOL p" button is pressed.) Then press
"1." The display will momentarily show "CUT OFF
R" (R=Red.) Now there should be a horizontal line
across the center of the picture tube. If needed,
gradually turn the screen control on the flyback
clockwise until the horizontal line appears. Adjust
the Red Cut off by pressing the "CH o / p" buttons.
Proceed to Step 5 when the Red Cut off adjustment
is done.
5. Press the "2" button. The display will momentarily
show "CUT OFF G" (G=Green.) Adjust the Green
Cut off by pressing the "CH o / p" buttons. Proceed
to step 6 when the Green Cut off adjustment is done.
6. Press the "3" button. The display will momentarily
show "CUT OFF B" (B=Blue.) Adjust the Blue Cut
off by pressing the "CH o / p" buttons. When
done with steps 4, 5 and 6, the horizontal line
should be pure white. If not, then attempt the Cut
off adjustment again.
Input
RF Black Raster
Spec.
Fig 2

9. White Balance Adjustment

Purpose: To mix red, green and blue beams correctly
for pure white.
Symptom of Misadjustment: White becomes bluish
or reddish.
Test Point Adj. Point
CH o / p
Screen
buttons
M. EQ.
Pattern Generator,
Color analyzer
Note: Use service remote control unit
1. Operate the unit more than 20 minutes.
2. Face the unit to the East. Degauss the CRT using
degaussing coil.
3. Input the White Raster (APL 100%).
4. Set the color analyzer to the CHROMA mode and
after zero point calibration, bring the optical recep-
tor to the center on the tube surface (CRT).
5. Enter the Service mode. Press "VOL p" button on
the service remote control unit and select "C/D"
mode. (Display changes "C/D," "7F," "LAN-
GUAGE," "ACCESS CODE," "SOUND TYPE,"
"VIDEO TONE," "FM-MODE," "V-OUT," "VIDEO,"
"AV-MEMO," "STABLE," "FILTER," "YUVMEMO-
RY" and "A-MUTE POL" cyclically when "VOL p"
button is pressed.) Then press "8" button on the
Service remote control Unit.
6. Press "4" button on the service remote control unit
for Red adjustment. Press "5" button on the service
remote control unit for Blue adjustment.
7. In each color mode, press "CH o / p" button to ad-
just the values of color.
8. Adjusting Red and Blue color so that the tempera-
ture becomes 9200K (x: 286 / y: 294) ±3%.
9. At this time, re-check that horizontal line is white.
(Refer to "Cut-off Adjustment".) If not, re-adjust
Cut-off Adjustment until the horizontal line be-
comes pure white.
10. Turn the power off and on again to return to normal
mode. Receive APL 100% white signal and confirm
that chroma temperatures become 9200K (x: 286 / y:
294) ±3%.
Note: Confirm that Cut Off Adj. is correct after this
adjustment, and attempt Cut Off Adj. if needed.
5-4
Mode Input
White Raster
RF
(APL 100%)
Spec.
See below
Figure
Color Analyzer
Fig. 3
L2200EA