Search

Distortion in feedback amplifiers and other non-linear circuits is analyzed for the case where the magnitude and phase of the feedback varies with frequency. The analysis is limited to cases where the distortion products are small compared to the fundamentals and where the non-linear element can be described by a power series having only a few terms. However, many practical amplifiers are adequately described by the analysis. Formulae are derived for a number of third-order products and their dependence upon various feedbacks at second order frequencies is demonstrated.

The equalization and regulation problems of the L3 system are described and a theory of equalization of complex systems is outlined. The location and function of the various equalizers are explained, including the roles and design of the various fixed, dynamic, and manual equalizer networks. The analogue computer used in the regulation system is described, together with the cosine-equalizer adjusting technique used with manual equalizers. Finally the circuits and operation of the regulation system and its components are presented.

The equalization and regulation problems of the L3 system are described and a theory of equalisation of complex systems is outlined. The location and function of the various equalizers are explained including the roles and design of the various fixed, dynamic and manual equalizer networks. The analog computer used in the regulation system is described together with the cosine-equalizer adjusting technique used with manual equalizers. Finally the circuits and operation of the regulation system and its components are presented.

A fully electronic telephone central office is being developed for experimental Bell System service. Both the electronic devices themselves and their system organization represent major changes in the art of telephone switching. The electronic switching system consists of electronic voice frequency switches controlled by electronic memory and logic. However, the system is not designed on the basis of direct substitution of electronic circuits for corresponding relay circuits of an existing switching system. Rather, the electronic circuits are organized in ways that exploit the advantages of the electronic technology.