Service manual

SERVICE MANUAL
CIRCUIT ADJUSTMENTS (continued)
Before Adjusting After Adjusting
SET-UP ADJUSTMENTS
The following adjustments should be made when a complete realignment is required or a new
CRT is installed. Perform the adjustments in order as follows.
1. Colour purity
2. Convergence
5. White Balance
Note
The purity/convergence magnet assembly and rubber wedges need mechanical positioning. Refer to
Fig. 18.
1. Colour Purity Adjustment
Note
Before attempting any purity adjustment, the TV should be operated for at least 15 minutes.
1
Demagnetize the CRT and cabinet using a degaussing coil.
2 Set the brightness and contrast to maximum.
3
Receive the green raster test signals.
4
Loosen the clamp screw holding the deflection yoke and slide it backward or forward to display
vertical green belt (zone) on the screen.
5
Remove the rubber wedge.
6
Rotate and spread the tabs of the purity magnet around the neck of the CRT until the green belt is on
the centre of the screen.
7
Slowly move the deflection yoke forward or backward until a uniform green screen is obtained.
Tighten the clamp screw of the yoke temporarily.
8
Check purity of the red and blue raster.
Dummy Wedge
Fig. 18
Glass Cloth Tapes
Purity/Convergence
Magnet Module
Deflection Yoke
Adhesive
Rubber Wedge
Deflection Yoke
39