Mutual Inductance in Wave Filters with an Introduction on Filter Design

Principles of Generalized Dissymmetrical Networks. We shall consider first the impedance and propagation characteristics of certain generalized networks. It can be shown that any passive network having one pair of input and one pair of output terminals may, at any frequency, be completely and adequately represented by an equivalent T or r net- 2 4 Fig. 1--Generalized Dissymmetrical T Network Connected to Impedances Equal to Its Image Impedances work.1 The impedance and propagation characteristics of any such network may be expressed in terms of its equivalent T or IT network. These characteristics are defined by (1) the image impedances, and (2) the transfer constant, the latter including the attenuation constant2 and the phase constant.- In the case of a symmetrical network, the image impedances and the transfer constant are, respectively, the iterative impedances (or characteristic impedances) and the propagation constant employed by Campbell, Zobel, and others. The terms involved will be subsequently defined. Consider the dissymmetrical T network of Fig. 1. If the 3 -- 4 terminals of the T network are connected to an impedance Z/2, the ' C a m p b e l l , G. A., "Cisoidal Oscillations," Transactions A. I. E. E., (1911), Vol. X X X , Part II, pp. 873-909. T h e T and n networks referred to above are sometimes called star ( F ) and (A) networks, respectively. 2 The real and imaginary parts of the transfer constant have been called by Zobel, the diminution constant and t he angular constant, respectively.