Panasonic TX-25P20T, Service Manual

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Colour Purity
1. Set the Brightness and Contrast controls to their maximum
positions.
2. Operate the TV set for over 15 minutes.
3. Fully degauss the picture tube by using an external
degaussing coil by rotating R-B static convergence magnet.
4. Apply a crosshatch pattern signal and adjust the static
convergence magnets roughly.
5. Apply a green pattern signal.
6. Loosen a clamp screw for the deflection yoke and move the
deflection yoke as close to the purity magnet as possible.
7. Adjust the purity magnetic so that a vertical green field is
obtained at the centre of the screen.
Fig. 20
8. Slowly press the deflection yoke and set it where a uniform
green field is obtained.
9. Adjust roughly the Low Light controls and make sure that a
uniform white field is obtained.
10. Tighten the clamp screw.
Convergence
1. Apply a crosshatch pattern signal and set Contrast control
to the maximum position.
2. Adjust Brightness control to obtain a clear pattern.
3. Adjust the Red and Blue line at the centre of the screen.
Fig. 22
4. Adjust Red and Blue with Green line at centre of the screen
by rotating (RB) -G static convergence magnet.
5. Lock convergence magnets with silicone sealer.
6. Remove the DY wedges and slightly tilt the deflection yoke
vertically and horizontally to obtain the good overall
convergence.
Fig. 23
7. Fix the deflection yoke by reinserting the DY wedges. Refer
to Fig. 24.
8. If purity error is found, repeat “Colour Purity” adjustment.
Before Colour Purity, Convergence and White Balance adjustments are attempted, V.
Center, V. Height, H. Width, H. Centre and Focus adjustments must be completed.
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TX-25P20T