Pulse Induction Metal Detector Using Sample and Hold Method

This paper presents the Pulse Induction Metal Detector Using Sample and Hold Method. The proposed method is to measure output voltage from search coil. The system consists of the pulse generator circuit, amplifier circuit, integrator circuit, three mono-stable circuits, sample and hold circuit, comparator circuit and display circuit. The voltage output signal of the proposed technique is proportional to size, shape and type of metal target. The metal target with differential size was used in our experiment as an illustrative case study. Experimental results show that the proposed method can detect metal with satisfied sensitivity and good linearity.