Vacuum Tube Oscillator Circuit. In an oscillatory circuit the tube does not become an oscillator it continues to act as an amplifier amplifying the voltage which is applied to its grid circuit and sending it through the circuit coupled to its plate. The advantage of using a vacuum tube is that they can oscillate at specified frequencies such as a thousand cycles per second.
In the class c oscillator the nonlinear properties of the tube stabilize the oscillation amplitude if a grid leak is used to obtain self bias. When the oscillator is first turned on the grid bias is zero and the amplifier gain is maximum. In this circuit the 005uf screen bypass capacitor is essentially a short circuit for rf and thus the 220pf capacitor is essentially connected between the screen oscillator plate and cathode of the tube.
The early oscillators used vacuum tubes which had limited life and were therefore high maintenance items.
In the class c oscillator the nonlinear properties of the tube stabilize the oscillation amplitude if a grid leak is used to obtain self bias. Any number of configurations may be used to generate rf signals using vacuum tubes. In the class c oscillator the nonlinear properties of the tube stabilize the oscillation amplitude if a grid leak is used to obtain self bias. When the oscillator is first turned on the grid bias is zero and the amplifier gain is maximum.
