dear Qiaozhi
thank very much for your feed back, i think this device is almost like Garrett eagle eye which i have already used it but it is not able to discriminate the targets. The problem is that these devices are grounding affected and given fake signals and because the ground here and basaltic volcanic, what is the solution?
http://www.kellycodetectors.com/garr...2500pro_th.htm
the buried boxes made of wood and full of gold coins in deep of 2 to 3 meter deep.the box is around 60cm*25cm*20cm.
regards