Q. Give the classification of oscillators. Discuss the frequency stability of oscillators.
Oscillators are classified in the following different ways.
1. According to the waveforms generated:
· Sinusoidal oscillator: This oscillator generates sinusoidal voltage or currents.
· Relaxation oscillator: This oscillator generates voltages or currents, which vary abruptly one or more times in a cycle of oscillation.
2. According to the fundamental mechanisms involved:
· Negative resistance oscillator: It uses negative resistance of the amplifying device to neutralize the positive resistance of the oscillator.
· Feedback oscillator: It uses positive feedback in the feedback amplifier to satisfy the Barkhausen criterion.