Fecha de publicación: 23/08/1946 Fuente: WIPO "royal booby" 580,015. Mine-detectors. CINEMA TELEVISION, Ltd., and WEST, S. S. March 30, 1944, No. 5886. Drawings to Specification. [CLass 40 (v)] A detector for non-metallic land mines or other buried objects comprises a set of ultrahigh-frequency sending and receiving aerials so balanced that reflection from homogeneous soil produces a null condition in the receiver, while asymmetrical reflection destroys the balance and gives rise to a signal. In one embodiment, two half-wave sending aerials are excited in anti-phase so that symmetrical reflections received by a receiving aerial located between them cancel one another ; but asymmetrical reflections from a buried object either differ in phase or amplitude at the receiving aerial or affect the impedances of the sending aerials unequally, so that a signal is received. Parasitically-excited elements may be introduced.