A simple apparatus to plot the variations of the dielectric permittivity versus temperature in the range of frequencies 10 Hz-100 kHz

摘要

An apparatus able to plot the variations of the real and imaginary parts of the dielectric permittivity of materials versus temperature in the range of frequencies from 10 Hz to 100 kHz is presented. The circuit is based on a simple operational amplifier followed by detection, low-pass filters, and amplifiers. The resulting two DC voltages, which are proportional to epsilon ' and epsilon ", are sent to a plotter whose x input is driven by the temperature of the sampled.