Magnavox CT270MW8 A, Руководство по обслуживанию

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1-7-5 T3200EA
8. White Balance Adjustment
Purpose: To mix red, green and blue beams correctly
for pure white.
Symptom of Misadjustment: White becomes bluish
or reddish.
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
a 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
receptor to the center on the tube surface (CRT).
5. Enter Service mode in TV Mode.
6. Press [VOL
p
] button on the service remote
control unit and select “C/D” mode. (Display
changes “C/D”, “7F” and Initial Setting cyclically
when [VOL
p
] button is pressed.)
7. Press [4] button to select “DRIVE (R) (DR)” for Red
adjustment. Press [5] button to select “DRIVE (B)
(DB)” for Blue adjustment.
8. In each color mode, press [CH.
o
/
p
] buttons to
adjust the values of color.
9. Adjust Red and Blue color so that the temperature
becomes 9200K (x: 286 / y: 294) ±3%.
10. At this time, re-check that horizontal line is white. If
not, re-adjust Cut-off Adjustment until the
horizontal line becomes pure white.
11. Turn 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.
9. Sub-Brightness Adjustment
Purpose: To get proper brightness.
Symptom of Misadjustment: If Sub-Brightness is
incorrect, proper brightness cannot be obtained by
adjusting the Brightness Control.
Note: SMPTE Setup level --- 7.5 IRE
1. Enter Service mode.
Then input SMPTE signal from RF input.
2. Press [PICTURE] button.
3. Press [1] button to selcet “BRT” display. (Display
changes “BRT,” “CNT,” “COL,” “TNT,” “V-T,” and
“SHP” cyclically when [1] button is pressed.)
4. Press [CH
o
/
p
] buttons so that the bar is just
visible (See above figure).
10. Focus Adjustment
Purpose: Set the optimum Focus.
Symptom of Misadjustment: If Focus Adjustment is
incorrect, blurred images are shown on the display.
Note: Focus VR --- FBT (Sub CBA),
FBT = Fly Back Transformer
1. Operate the unit more than 30 minutes.
2. Face the unit to the East and degauss the CRT
using a degaussing coil.
3. Input the monoscope pattern.
4. Adjust the Focus VR on the FBT to obtain a clear
picture.
Test Point Adj. Point Mode Input
Screen
[CH.
o
/
p
]
buttons
RF
White Raster
(APL 100%)
Tape M. EQ. Spec.
---
Pattern
Generator,
Color analyzer
See below
Figure
Fig. 3
Color Analyzer
Test Point Adj. Point Mode Input
---
[CH.
o
/
p
]
buttons
---
SMPTE
7.5IRE
Tape M. EQ. Spec.
---
Pattern
Generator
See below
Figure
Fig. 4
Test Point Adj. Point Mode Input
--- Focus VR --- Monoscope
Tape M. EQ. Spec.
--- Pattern Generator See below
White
Black
This bar
just
visible