GB432515A - Improvements in and relating to compensation elements for reducing the crosstalk in trunk communication cables - Google Patents

Abstract

432,515. Preventing inductive disturbance. SIEMENS & HALSKE AKT.- GES., Siemensstadt, Berlin. Oct. 31, 1934, No. 31267. Convention date, Oct. 31, 1933. [Class 40 (iv)] In order to minimize cross-talk in the case of lightly-loaded lines and high-frequency lines, it is important to balance the inductive couplings between conductors in addition to the capacity couplings, and this is effected by the use of corrective capacity elements which also provide an inductive coupling, the ratio of the inductive coupling being approximately the same as the corresponding ratio for the quads or conductor groups to be compensated. The ratio may be adjusted by varying the form and the spatial arrangement of the condenser plates and by suitable choice of dielectric or by interposition of magnetic material. Small supplementary capacity or inductance elements may be added if necessary. The element may be subdivided so as to provide an initial rough compensation and a supplementary fine compensation. The element may take the form of two or more coils inductively coupled together and dimensioned so as to give the desired capacity coupling. The elements shown are suitable for balancing quads and comprise four wires which are round in Fig. 1 and of angular section in Fig. 2 and which constitute the condenser plates. These wires are arranged in spiral quad form and are insulated by material 16 of high dielectric constant, the whole being surrounded by a sleeve 15, 25 of insulating material or of metal.