Theory of 2n-terminal networks with applications to conference telephony

Networks composed of resistors and ideal transformers simultaneously matched at all their terminal pairs to a given set of resistors and having prescribed losses between various terminal pairs are treated. The requirements are expressed by an effciency (scattering) matrix from which the impedance or admittance matrix is derived, these being realizable by standard methods. Applications to design of 6- and 8-terminal networks are given. The special case of a matched non-dissipative natwork inter-connecting n telephone circuits, thus giving a loss of 10 log10(n-1)db between all terminal pairs, is examined in detail and a series of possible values of n derived. Interconnection of 4-wire circuits is mentioned.