Toroidal Convergence Unit With Unbalanced 4-Pole Winding
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-08
U.S. Patent 4,339,736 describes a dynamic convergence unit for an in-line color cathode ray tube in which a toroid is divided into segments provided with windings which result in 4-pole and 6-pole magnetic fields. In a particular implementation using 12 segments, the 4-pole windings were configured as 20 turns per segment for four segments (inductance 68 mH) and 12 turns per segment for 8 segments (inductance 68 mH). This is shown in Fig. 1, which also shows the 6-pole windings in which each field uses six segments with 18 turns per segment (inductance 64 mH). In Fig.1, the dotted lines 6V and 6H represent the two 6-pole fields. The chained lines 4V and 4H represent the two 4-pole fields.