Discussion of Oscillation in Tuned Radio-Frequency Amplifiers, by B.J. Thompson

B.J. Thompson in the above referenced article (ibid., vol 19, pp 421, Mar 1931) makes the following statement - "Hull and more lately Nelson have analyzed the conditions for stability in terms of the maximum amplification per stage, ignoring the allimportant effect of feed-back on amplification." He evidently did not understand the significance of the symbol Av in either of the above articles. The effect of feed-back has not been ignored in determining the conditions for stability. The voltage amplification Av is not the amplifaction realized with a tuned input but is the amplification obtained with an untuned input or the true repeater gain of the stage, which quantity may be easily measured. The desirability of expressing the results in terms of Av is discussed.