The Tuned-Grid, Tuned-Plate, Self-Oscillating Vacuum-Tube Circuit

Certain discrepancies in published reports on this circuit are pointed out and it is shown that the frequency of oscillation is given by the real terms and the necessary condition for these oscillations to start by the imaginary terms of the general equation. Equations are set up for the frequency and for the necessary conditions for the generation of oscillations of a frequency determined by the tuning of the grid circuit. The feedback is assumed to be through the grid-plate capacity of the vacuum tube.