The phase shift oscillator in the diagram uses two all-pass filters, A2 and A3, and an inverting amplifier, A1. The ideal gain for A1, A2 and A3 is 1 when R2=R3, resulting in a loop gain of 1. In ...

The old movie “Gremlins” showed how some cute, adorable, furry little creatures, so seemingly innocent, could and did cause lots of trouble. To me, the classic phase shift oscillator is the gremlins' ...