*Based on wave generated:
i. Sinusoidal Oscillator,
ii. Non-sinusoidal Oscillator or Relaxation Oscillator
Ex: Square wave, Triangular wave, Rectangular wave etc.
*According to principle involved:
i. Negative resistance Oscillator, ii. Feedback Oscillator.
*According to frequency generated:
i. Audio frequency oscillator
20 Hz – 20 kHz
ii. Radio frequency Oscillator
30 kHz – 30 MHz
iii. Ultrahigh frequency Oscillator
30 MHz – 3 GHz
iv. Microwave Oscillator
3 GHz – above.
* Crystal Oscillators.
* RC-Phase shift Oscillator,
* LC-Oscillators
i. Tuned collector Oscillator
ii. Tuned emitter Oscillator
iii. Tuned collector base Oscillator
iv. Hartley Oscillator
v. Colpits Oscillator
vi. Clap Oscillator