| The basic principle type and application of the Metal Detectors are generally introduced in this paper.The testing electric circuits of all kinds of induced Metal Detectors are mainly introduced.The effect of all factors on sensitivity and stability of Metal Detector are discussed.It is concluded that the operating frequency,the size of the testing coil and turns are the main factors effected on the sensitivity of the instruments,the environment temperature and humidity in site,the winding technology of the coils and the stability of power supply are the factors effected on the stability of instrument. |