Research in the field of monitoring and registration of geophysical disturbances, being a complex scientific and technical problem, is of great applied importance. Perturbations of fluctuating media have a significant impact on the functioning of technical systems for control, safety, navigation, communications, etc. For this reason, the development of methods and tools for monitoring and recording geophysical disturbances is an urgent task in many areas of science and technology. The article discusses a method for registering geophysical disturbances in fluctuating media using a spatially separated radioacoustic generator. The event registration method is based on comparing the phase of the acoustic signal received from the fluctuating medium with the phase of the signal emitted into the controlled environment. The output signal of the phase detector is a DC voltage described by a monotonic function of the phase difference of the input signals. A condition for self-excitation of a spatially separated radioacoustic generator is formulated, which is determined by the general solution of the transient component of a second-order differential equation. The block diagrams of the technical implementation of the method are presented. The principle of registration of disturbances is based on the comparison of the phases of the signals received and emitted into the controlled environment. Based on the results of the experimental study, the phasegram of the output signal of the phase detector is presented as a reaction to the throwing of objects of various sizes into the zone of propagation of the acoustic beam. The results of the study are relevant for the following areas of application: sounding of continental sea and ocean shelves, monitoring of vortex and turbulent disturbances in the airspace of airport runways, control of sea waves and underwater currents in the waters of seaports, detection of foreign objects in protected areas.