A Bridged T Network in Action

Abstract

A marked preference is greatly in evidence in recent years on the part of both manufacturers and users of high power broadcast transmitters in favour of a design that incorporates two smaller transmitters, of half the power each, whose outputs are combined to give the full power of the station. The reason for this contemporary trend is the greater emphasis laid on reliability of service and in some cases technical or economic considerations requiring reduction of operating powers at certain times. Historically, this design has been the outcome of attempts in the post-war era, to provide unattended transmitters with Robot monitors. Frequently, a bridged T network is employed to combine the outputs of the two transmitters and the article explains in simple terms how several functions are carried out by the bridged T arrangement. It is hoped that the article will be of interest to students and professional radiomen alike.