Stray-Effect-Free Direct Impedance-to-Frequency Converter
Makoto Kanno, Toshiro Horikawa · IEEE Transactions on Instrumentation and Measurement · 1978
A variety of oscillator circuits which employ three- or four-terminal impedance sensors is introduced. An example showed that the capacitance-frequency characteristic obtained with a variable capacitor attached to the circuit was unchanged even when the capacitor was separated 7.5 m away from the circuit by two coaxial cables.