I do not know about this detector who invented , making it very simple , the effect is also very good. Production materials: some ordinary pencil lead ( 15-20 mm ) and an insurance blade ( not rusty ) components.
This detector is working well, making simple, only one fault : a sensitive point easy to find, in addition , we must constantly sharpen pencil . There is also a most important role ore detector is to produce ore radio. It can transfer station , can be very powerful radio station to listen to loud sounds , as well as coils , etc., can be said that the ore machine a professional machine . Nodes with different coarse tuning coil , a variable capacitance fine tuning. In the machine after seeing a professional to do the most simple, basic radio is still very interesting. Ore machine is not only a masterpiece of amateurs , the Soviet Union has produced a wide variety of industrial minerals machines, such as " Komsomolets " and so on . Now a machine factory production of precious ore than transistor radios.
In the Soviet Union, was once a popular zincite crystal detector , a Nigerian city of Novgorod Radio Laboratory have come up with was a researcher Losev was a special processing method was red after zinc crystal detector , it can produce oscillations and to a certain extent was enlarged . I do not have detailed technical information .