Sanyo CP21FS2, Service Manual

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Purity and Convergence Adjustment
RED
BLUE
Adjust tabs togeth-
er to superimpose
red and blue hori-
zontal line.
Figure- 2 BLUE AND RED LINE MOVEMENT
Figure- 3 BLUE/RED AND GREEN MOVEMENT
Adjust tabs togeth-
er to superimpose
red/blue and green
horizontal line.
Adjust tabs angle to superimpose
blue and red vertical line. Adjust tabs angle to superimpose
red/blue and green vertical line.
GREEN
BLUE / RED
CAUTION: The Convergence and Purity adjustments have been made at the factory. Readjustment
should be made only after picture tube or deflection yoke replacement, following the steps below:
PURITY ADJUSTMENT
1. Demagnetize the picture tube and receiver using an external
degaussing coil. When replacing picture tube or deflection yoke,
mount deflection yoke and purity-convergence magnets assembly
properly, see figures 1 and 4.
2. Turn Red and Blue guns off and provide only Green raster. Rotate
Screen control to fully counterclockwise. Rotate Red and Blue
Bias controls fully counterclockwise. Slowly rotate Green Bias
control clockwise to produce Green raster.
3. Loosen the screw holding the Deflection Yoke and remove the 3
Rubber Wedges, and slide the Deflection Yoke fully forward.
4. Rotate and spread the Tabs of the two Purity Magnets to centre
the vertical green belt in the picture screen. The Purity Magnets
are also adjusted to obtain vertical centring of the raster.
5. Slowly slide the Deflection Yoke backward until a uniform green
screen is obtained.
6. Check the purity of the red and blue screens for uniformity, turn off
other colours to check this (use bias controls). Readjust the yoke
position if necessary until all screens are pure.
7. Adjust each Bias control and screen control to obtain white raster.
Refer to Gray Scale Adjustment. If part of the picture screen is
coloured, adjust the Deflection Yoke position forward or backward
slightly.
8. Tighten the mounting screw of the Deflection Yoke. Adjust
Convergence next.
CENTRE CONVERGENCE ADJUSTMENT
1. Use a dot crosshatch pattern signal.
2. Turn Red and Blue guns on and turn off Green gun. Adjust the
angle between the Tabs of the Four Pole Magnet 1 and 2, and
superimpose the Red and Blue vertical lines in the centre area of
the picture screen. Refer to figure 2.
3. Keeping the mutual angle of the Tabs of the Four Pole Magnet
turn them together to superimpose the Blue and Red horizontal
lines in the centre area of the picture screen. Refer to figure 2.
4. Turn Green gun on and adjust Six Pole Magnet 3 and 4 that the
Green line superimposed on the Red/Blue lines.
This is the same procedure used in steps 2 and 3.
Refer to figure 3.
5. If horizontal lines are intersecting at the top and bottom, use a
screwdriver to adjust the Balance Coil at the top of the deflection
yoke. Refer to figure 6.
OUTER AREA CONVERGENCE ADJUSTMENT
Slightly loosen the screw holding the Deflection Yoke. Adjust the
Deflection Yoke to converge the detail in the outer area (left side
and right side) of the picture screen by orbital movement of the
front of the Yoke, then secure the Deflection Yoke in appropriate
position by putting the wedges as illustrated. Tighten screw hold-
ing the Deflection Yoke.
Figure 4. Deflection Yoke Movement
SIX-POLE
MAGNET TABS
FOUR-POLE
MAGNET TABS
ANGLE
OF TABS
PURITY
MAGNET
TABS
4
3
2
1
FOCUS GAP
(G3-G4)
Figure 1. Purity and Convergence Magnets
MAGNET TABS
ANGLE OF MAGNET TABS
Figure 5. Adjusting Magnet
Note: The form of deflection yoke changes with models.
DEFLECTION
YOKE
RUBBER WEDGE
DEFLECTION YOKE
MOUNTING SCREW
BALANCE COIL
Figure- 6 BALANCE COIL ADJUSTMENT
Blue
Red
Use the Balance coil to correct.
SM_21-C8YY(FC6-A)AUS-Slim 8/24/06 9:23 AM Page 18