[mehdi]

Originally Posted by vali

hello mehdi.
nobody exactly knows that the metal who buried under the soil for many years do it produce invisible corrosion or smell, magnetic field and either it may be produced the powerless voltage that we are ignorant of them .but the suggestions of some people is that it produce by means of earth circulation . and this circuit that i have made will respond to all of them..
profession_ electronics.......
best wishes vali

Hi vali
i agree with you.