Analogue modelling an array of the FitzHugh–Nagumo oscillators

The purpose of the paper is to show that analogue electronic modelling is an extremely fast technique compared to conventional digital computing, especially when solving large sets of coupled nonlinear differential equations. An array of thirty FitzHugh–Nagumo type electronic oscillators, modelling dynamics of the brain neurons, is considered. The decrease of time consumption by a factor of several thousands is demonstrated. The work delivers a perspective of how to implement convenient analogue models of complex dynamical networks

Stabilizing uncertain steady states of some dynamical systems by means of proportional feedback

A simple zero-order proportional feedback technique for stabilizing unknown fixed points is described. The technique employs either artificially created or natural stable fixed point to find the coordinates of the unknown unstable fixed point. Four physical examples have been investigated, namely the mechanical pendulum, the autonomous Duffing damped oscillator, the van der Pol oscillator, and the Lorenz system have been considered both analytically and numerically

Autonomous Silva-Young type chaotic oscillator with flat power spectrum

A novel Silva-Young type fourth-order autonomous chaotic oscillator is described. In comparison with the original nonautonomous SilvaYoung circuit it lacks the external periodic driving oscillator, but includes a passive internal secondorder resonant LRC circuit, inserted in the positive feedback loop. In contrast to many other nonautonomous and autonomous chaotic oscillators, the suggested circuit exhibits fairly flat power spectrum of the output signal. Hardware experimental results and numerical results are presented. Good agreement between numerical and experimental results is observed

Analogue modelling an array of the FitzHugh–Nagumo oscillators

The purpose of the paper is to show that analogue electronic modelling is an extremely fast technique compared to conventional digital computing, especially when solving large sets of coupled nonlinear differential equations. An array of thirty FitzHugh–Nagumo type electronic oscillators, modelling dynamics of the brain neurons, is considered. The decrease of time consumption by a factor of several thousands is demonstrated. The work delivers a perspective of how to implement convenient analogue models of complex dynamical networks

Fast Chaos with Slow p-n Junction Diodes

We demonstrate both experimentally and numerically that slow recovery p -n junction diodes can be exploited to generate chaos at high megahertz frequencies. An extremely simple resonator consisting of an inductor in parallel with a diode when externally periodically driven exhibits chaotic response

"Indoor" protection of electronic systems by means of high-pass negative feedback

An extremely simple first order RC high-pass filter is suggested to suppress harmful radio frequency oscillations, induced by high power electromagnetic pulses. Specifically, a broadband single stage transistor amplifier with a parasitic wiring inductance and also the parasitic junction and mounting capacitances are investigated both numerically and experimentally in the very high and ultrahigh frequency bands

Fast chaos with slow, p -n junction diodes

We demonstrate both experimentally and numerically that slow recovery p -n junction diodes can be exploited to generate chaos at high megahertz frequencies. An extremely simple resonator consisting of an inductor in parallel with a diode when externally periodically driven exhibits chaotic response