The Piezo-Electric Resonator in High-Frequency Oscillation Circuits

By "piezo-electric, coupler" is understood a piezo-electric resonator provided with two pairs of electrodes, by which, in the neighborhood of a frequency of mechanical resonance, electric energy may be transferred from one circuit to another. As the voltage transformation ratio between primary and secondary voltages is especially important in practice, this transformation ratio is investigated somewhat fully, and some experimental results are described. It is noted that this ratio must have a negative real component in order that the coupler may act as a regenerative linking device between anode and grid circuits of a tube oscillator. In the study of the effects of a crystal resonator on an electric circuit in which it is placed, the application of its motional admittance circle diagram has many advantages. Some theoretical applications are, for example, made in the present paper in considering the characteristics of a piezo-electric oscillator and of a piezo-electric frequency stabilizer. Representing the crystal resonator, which is an electro-mechanical vibrator, by an electrical circuit, we can obtain the conditions for the building up of oscillations in a piezo-electric oscillator. Three types of oscillators are treated here. The effective frequency-stabilizing action of a tube oscillator by means of a crystal resonator is considered from the point of view of the so-called "Zieherscheinung" in the case of a tube oscillator containing coupled oscillation circuits.