Electronic Integrator for Micrometeorological Data

Abstract

A transistorized, battery-operated integrator suitable for obtaining the time average of fluctuating electrical analogue signals in the field with relative errors of about 0.1 to 0.2 per cent is described. A solid state operational amplifier is used in an R-C integrator circuit. Continuous integration is accomplished by reversing the polarity of the input signal each time a fixed time-integral has occurred. The addition of a resistor to the ordinary R-C integrating circuit reduces the error resulting from the finite switching time. The integral is obtained by counting the input polarity reversals which are registered on a counter (mechanical or electronic) to be automatically recorded at desired intervals. The use of transistor converters allows the complete circuit as well as additional equipment to be operated several days from one 12V automobile battery.