Hartley oscillator

Colpitts oscillator

un tuned collector oscillator

Wein bridge oscillator

R.C. phase shift

Wein bridge

L.C. oscillator

Blocking oscillator

produces sinusoidal output

produces non-sinusoidal output

relaxes indefinitely

oscillates continuously

mass of the crystal

square root of the mass of the crystal

square of the mass of the crystal

inverse of the square root of the mass of the crystal

Both use positive feedback

The former uses positive feedback only, whereas the later uses both positive and negative feedback.

The former uses both positive and negative feedback only whereas later uses positive feedback

Both use negative feedback