Two Twin-T based op amp oscillators modified for chaos

Two complementary sinusoidal oscillator circuits based on the Twin-T network are modified for chaos using a single discrete nonlinear device with antisymmetrical current-voltage characteristics, namely a junction field effect transistor (JFET) operating in its triode region. The two oscillatorsʹ design equations are used as a starting point for chaos modification. Mathematical models that describe the observed behaviour in both circuits are derived. Experimental results, PSpice circuit simulations and numerical simulations of the mathematical models agree well and are included.