Abstract: An apparatus for measuring a moisture content value within a volume. A frequency generator generates at least one source signal at frequencies of no more than about one kilohertz. Probes are disposed with surfaces in physical contact with the volume, where no direct current flows between the probes through the volume. One of the probes is electrically connected to the frequency generator as a source probe, and adapted to receive the source signal and emit the source signal into the volume, thereby creating an electrical field having characteristics that are dependent at least in part on a moisture content of the volume. Another of the probes operates as a receiver probe for sensing the electrical field and producing an output signal having an output property that is dependent at least in part on the source signal and the moisture content within the volume.