THOMSON MCR61TF30, Service Manual

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SERVICE MANUAL
ADJUSTMENTS
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
3. 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 pattern.
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 center 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.
Glass Cloth Tapes
Purity/Convergence
Magnet Module
Deflection Yoke
Adhesive
Rubber Wedge
Dummy Wedge
Deflection Yoke
Fig. 18
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