Color Purity Adjustment - Daewoo TVZ 1321 Service Manual

8. CONVERGENCE MAGNET ASSEMBLY
POSITIONING
Convergence magnet assembly and rubber wedges need
mechanical positioning following the figure 2.

8-1. COLOR PURITY ADJUSTMENT

NOTE : Before attempting any purity adjustments, the
receiver should be operated for at least 15 minutes.
1) Demagnetize the picture tube using a degaussing coil.
2) Vary the CONTRAST and BRIGHTNESS controls to
maximum.
3) Adjust RED and BLUE Bias controls (RJ04 and RJ24) to
provide only a green raster. Adjust the GREEN BIAS
control (RJ13) if necessary.
4) Loosen the clamp screw holding the yoke, and slide the
yoke backward to provide a vertical green belt (zone) in
the picture screen.
5) Remove the Rubber Wedges.
6) Rotate and spread the tabs of the purity magnet (see fig-
ure 2) around the neck of the picture tube until the green
belt is in the center of the screen. At the same time, cen-
ter the raster vertically.
7) Move the yoke slowly forward until a uniform green
screen is obtained. Tighten the clamp screw on the yoke
temporarily.
8) Check the purity of the red and blue raster by adjusting
the BIAS controls.
9) Obtain a white raster, referring "CRT GRAY SCALE
ADJUSTMENT" on the CRT board.
10) Proceed with convergence adjustment.
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