Transistorized RC phase-shift power oscillator

A transistorized RC phase-shift oscillator is very similar to the electron tube circuit. Two important differences are: 1) A transistor possesses active phase-shift elements which can be utilized as part of the total phase shift; 2) large current capabilities of the transistor make it possible to obtain significant power at reasonable resistance values. The small-signal analysis given herein is based upon a hybrid-π transistor equivalent circuit which includes the active phase-shift elements of the transistor. Data are given for some operating circuits. Frequency modulation of the transistorized phase-shift oscillator can be readily carried out by modulating the transistor active phase-shift elements.