CRT with saddle deflection yoke - has two permanent magnets which prevent central axis distortion

摘要

The tube is a colour TV picture tube with a conical neck. It has conventional vertical deflection coils on the vertical axis of the yoke. The horizontal deflection coils are wound on a plastic coil former, which has an outer flange in contact with the glass envelope of the tube. The saddle coils have several segments which come together and run parallel to each other with a narrow horizontal gap between them. The gap is held constant by wedges which also hold small permanent magnets in position in the gap on either side of the aperture through which the tube neck passes. The magnets are 400 gauss nickel or magnesium zinc ferrites. The effect of the magnets is to counteract barrel distortion.