| Type of Oscillator | Approximate frequency range |
| Crystal oscillator | Fixed frequency |
| Tickler feedback oscillator | Nearly fixed frequency |
| Wien bridge oscillator | 1 Hz to 1 MHz |
| Phase-shift oscillator | 1 Hz to 10 MHz |
| Hartley’s oscillator | 10 kHz to 100 MHz |
| Colpitt’s oscillator | 10 kHz to 100 MHz |