Techniques for operating a sensor are provided. An example method according to these techniques includes sensing, at the sensor, changes in intensity of a magnetic field of a magnet affixed to a monitored asset to produce sensor data, wherein the monitored asset is disposed in a non-metallic liquid or solid medium, and wherein the sensor is disposed outside of the non-metallic medium; The method also includes analyzing, at the sensor, the sensor data to produce feature information indicative of vibration of the monitored asset. The method also includes providing the feature information to a predictive algorithm to generate prognosis information indicating an occurrence of a known condition of the monitored asset.