Auto-self-excited transductors and push-pull circuit theory

The modes of action of the parallel, bridge and centre-tap transductor connections are explained, and factors influencing the choice of circuits are discussed. Theoretical expressions are derived for the sensitivity and timeconstant under idealized conditions, and are considered for design purposes. Methods of controlling the transductor gain are briefly discussed. The paper discusses the use of push-pull transductor pairs, to obtain magnetic amplifiers with outputs that are duo-directional depending on the signal sense; the commonly-used push-pull arrangements are examined, analytically and experimentally, for auto-self-excited transductor pairs. The theoretical and practical performance of the arrangements are compared, and guidance is given on suitable design proportions.