Capacitance probe assembly

A two terminal type capacitance probe assembly, adapted to be capacitatively coupled with a return plate means by a fluid under analysis, comprising:

• (a) a generally linear array of discrete active plates mounted within a shell made from a dielectric material so that the plates are capacitance coupled to the fluid but are resistively insulated from the fluid;
• (b) a plurality of discrete oscillator circuits;
• (c) means for energizing the oscillator circuits;
• (d) each oscillator circuit being individually and permanently connected to an active plate for directly charging and discharging that active plate so that the frequency of the applied potential varies with the dielectric constant of the fluid extending between that active plate, which is a first terminal of the assembly, and the return plate means, which is the second terminal, to produce variable frequency signals indicative of said dielectric constant;
• (e) means for selectively and individually enabling an oscillator circuit;
• and
• (f) means for collecting the individual signals produced by the oscillator circuits and determining for each signal a value indicative of the dielectric constant of the fluid extending between the active plate involved and the return plate means.