A vibration transducer module for detecting a vibratory signal, comprising a base, a spring connected to the base at a first location, a mass mechanically coupled to the spring at a second location remote from the first location, and a wall configured to position a first wall electrode and a second wall electrode a selected distance from the first location, the conductive element positioned and sized to contact the first wall electrode and the second wall electrode. The mass comprises a conductive element, and an energy harvester to provide a first voltage signal. The energy harvester may comprise a piezoelectric material or be construct as a SAW device. The module may be combined with a rectifier and an oscillator to form a vibration sensor.