Abstract: A moisture sensor having an oscillator circuit with its output frequency directly proportional to moisture percentage present in the substance of interest, such as soil. The oscillator circuit includes two spaced plates in the substance which function as a capacitor. The frequency of the oscillations changes as the capacitance between the plates changes due to the moisture present between the plates. The sensor is particularly adapted for use as a soil moisture detector and provides indications of moisture percentage or end points such as wet or dry conditions.

Abstract: A moisture sensor having an oscillator circuit with its output frequency directly proportional to moisture percentage present in the substance of interest. The oscillator circuit includes two spaced plates in the substance and functioning as a capacitor. The frequency of the oscillations changes as the capacitance between the plates changes due to the moisture present between the plates. The sensor is particularly adapted for use as a soil moisture detector and provides indications of wet or dry conditions.