The Operational Characteristics of Thermionic Amplifiers

In a first addendum, the author shows a later method of measuring directly the mutual conductance of tubes, which method is free from certain possible objections of the earlier procedure. In a second addendum, an autodyne oscillator with inductive coupling between grid and plate circuits is analytically considered. The condition for sustained oscillation is derived, a numerical illustration given, and the value of the optimum mutual inductance between grid and plate circuits for oscillation is obtained.