Abstract: A method and means is described for a concealed structure locating and surveying exciter apparatus, and more particularly, to a portable device which couples, either by direct or indirect connection, high frequency alternating current energy into a more conductive structure which is usually obscured in a less conductive covert medium. The preferred embodiment provides two different frequency high stability sources of first oscillations the outputs of which are alternately switched or gated by a very low frequency source of second oscillations. The alternating first oscillations are combined in a summing amplifier and caused to drive an output coupling means. The amplified outout is further modulated, usually at an audio frequency rate, by a low frequency source of third oscillations.