Panasonic TX-21PM30T, Service Manual

Page: 9 / 29

Before Colour Purity, Convergence and White Balance adjustment are attempted,
V. Height, H. Centre and Focus adjustments must be completed.
Colour Purity Convergence
1. Set the Brightness and Contrast controls to 1. Apply a crosshatch pattern signal and
their maximum postions. Normalize Contrast control to the
2. Operate the TV set for 30 minutes. maximum positions.
3. Fully degauss the picture tube by using an 2. Adjust Brightness until the grey position of
external degaussing coil. the crosshacth pattern just becomes black.
4. Apply a crosshatch pattern signal and adjust 3. Adjust the Red and Blue line at the centre of
the static convergence magnets to the the screen by rotating the R-B static
approximately correct position.
5. Receive a black and White signal.
6. Set the control as following:
Red ................ minimum
Green ............. minimum
Blue ............... minimum
Press the Shipping button on the remote control
twice to select CRT Adjustment Mode as per
Fig. 16 to select low light.
7. Loosen the clamp screw for the deflection yoke
A in Fig. 24 and move the deflection yoke as close
to the purity magnet as possible.
8. Adjust the purity magnetic rings so that a vertical
green field is obtained at the cntre of the screen.
Fig.22
4. Adjust Red and Blue with Green line at
centre of the screen by rotating (RB) -G
static convergence magnetic rings.
5. Lock convergence magnetic with silicne
sealer.
6. Remove the DY wedges and slightly tilt the
deflection yoke vertically and horizontally to
obtain the good overall convergence.
Fig.20
9. Slowly push the deflection yoke and set it where
a uniform green field is obtained.
10. Re-adjust the Low Light controls to their correct set-
tings and make sure that a uniform white field is
obtained.
7. Fix the deflection yoke by re-inserting the DY
11. Tighten the clamp screw A in Fig. 24. wedges.Refer to Fig. 24.
8. If purity error is found, repeat “Colour
Purity” adjustment.
Slide magnetic tabs toward or away from
each other.
R-B Static
Convergence Magnet
Vertical
Convergence
Red & Blue
Horizontal
Convergence
Red & Blue
Rotate both magnetic rings together.
R-B Static
Convergence Magnet
Vertical
Horizontal
RGB
R
G
B
R
G
B
BGR
BGR
Purity Magnet Green Field
Colour Purity
Green
Uniform
green
Fig. 21
Fig. 23