Indicial Response of Telephone Receivers

Abstract

A method of analyzing telephone receiver characteristics by indicial response is discussed and illustrated by oscillograms. The indicial response of a telephone receiver is the instantaneous response of the receiver to a suddenly applied electromotive force. This type of response is of particular fundamental interest because it furnishes a key to the solution of transient problems such as are involved in the response to speech waves. Oscillograms of indicial response, together with the more familiar steady‐state frequency response characteristics, are shown for different types of receivers. The relationships existing between the two types of measurements are discussed. From the standpoint of most faithfully reproducing transients, indicial response data indicate that a receiver having a limited range of frequency response should have a frequency response characteristic which droops gradually rather than abruptly near the upper end of the range.