Oscollators, Multivibrators, Triggers and Flip-Flops

Below, we discuss some oscillators that generate sinusoidal, as well as other periodic signals. The main principle of oscillating circuits is the use a voltage amplifier with positive feedback. This makes the circuit unstable and constantly oscillating. In signal generators there must also be present an element that defines the frequency. In high frequency oscillators this is an LC circuit. If we want to generate low frequency signals, the inductances may be impractical, for their physical size. So, in low frequency oscillators rather RC circuits are used. The typical oscillators, like the phase-shift, Wien bridge, twin T, Colpittz and Hartley are described. Other, non-sinusoidal oscillators are considered, including the relaxation oscillator, multi-vibrator and others.