Symphonic ST27S3, Руководство по обслуживанию

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5-6 L6609EA
13. 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) - Main 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 Degaussing Coil.
3. Input the Monoscope Pattern.
4. Adjust the Focus Control on the FBT to obtain
clear picture.
The following 2 adjustments normally are not
attempted in the field. Only when replacing the
CRT then adjust as a preparation.
14. Purity Adjustment
Purpose: To obtain pure color.
Symptom of Misadjustment: If Color Purity Adjust-
ment is incorrect, large areas of color may not be
properly displayed.
1. Set the unit facing east.
2. Operate the unit for over 30 minutes before adjust-
ing.
3. Fully degauss the unit using an external degauss-
ing coil.
4. Loosen the screw on the Deflection Yoke Clamper
and pull the Deflection Yoke back away from the
screen. (See Fig. 6)
5. Loosen the Ring Lock and adjust the Purity Mag-
nets so that a red field is obtained at the center of
the screen. Tighten Ring Lock. (See Fig. 5,6)
6. Slowly push the Deflection Yoke toward bell of
CRT and set it where a uniform red field is ob-
tained.
7. Tighten the clamp screw on the Deflection Yoke.
Test Point Adj. Point Mode Input
--- Focus Control ---
Mono-
scope
Tape M. EQ. Spec.
---
Pattern
Generator
See below
Test Point Adj. Point Mode Input
---
Deflection
Yoke Purity
Magnet
---
Red
Color
Tape M. EQ. Spec.
---
Pattern
Generator
See below.
Figure
GREEN RED BLUE
Fig. 5