An analog multiplier using thyrite

Abstract
An investigation into the use of thyrite as an inexpensive nonlinear element in the electronic analog computer indicates that this material has great value as a device capable of delivering an output voltage proportional to the square of the input voltage. The factors discussed are the characteristics of the material and the means by which these may be modified to produce a device capable of squaring with an accuracy of 1.25% from dc to frequencies in excess of 1000 cps. This ability to square makes possible the more important operation of the multiplication of two variable voltages.