Digital Computer Calculation of the Operation of Nonlinear Devices with Energy Storage Elements

This paper presents results on digital computer calculation of the operation of some tube and transistor circuits which combine nonlinear operation with energy storage elements. The Class C amplifier, the frequency multiplier and the blocking oscillator are all circuits of this type. This approach allows many of the conventional restrictions on analysis procedures to be removed. For instance, in the case of the Class C amplifier, it is not necessary to assume that the plate and grid voltages are sinusoidal and the circuit at steady state. Additional features of computer use are the automatic calculation of efficiencies, plotting of waveforms and calculation of harmonic content; the facility of studying the effects of transients and modulation; the possibility of allowing the circuit parameters to take on any values or vary with time or with the voltages and currents; and the possibility of allowing the circuit associated with the device to be more complicated than usually allowed by other methods. Limitations to this approach lie in the cost of programming the problem, and the cost of running the program on an available computer. Questions of numerical accuracy sometimes arise, but can usually be handled with additional programming or running time. If a translator is available which can accept programs in the form of algebraic equations, the programming cost is often negligible. However, running time costs may be appreciable, particularly in the case of a complicated circuit with many storage elements.