A Voltage Stabilized High-Frequency Crystal Oscillator Circuit

The theory and line of reasoning used in developing this circuit are described. The circuit elements aside from the crystal are resistors and capacitances. The type 57 tube was found to fulfill to a large measure the requirements of a sufficiently high mutual conductance and a fairly high internal plate resistance in the oscillating state. A method of varying the frequency of oscillation is described. The stability using a seven-megacycle crystal was found to be within about one in twenty million for a ten per cent variation in either or both the filament and plate voltages.