well,i just wanted to share with you my metal detector that i working on,it's falls under the name of the T.G.S.L MD, a while ago i decided to make this device for the main reason that my government god damnit prevent those MD's in my country and there's a lot of archaeological places,anyway some friends from institute has contributed to provide assistance and gave some ideas, then i did some drastic changes to the schematic to improve it, and i have succeeded to conduct this achievement over the past week and took about one month to build it,as a result you can assess it as an average performance since the device can detect about 35-38 cm in the soil and with good discrimination;it can ignore iron and its derivatives.
here is the schematic that my MD based on:
and this pic show the board with it's components and the search coil:
anyway still need a proper and decent casing for it so when i walk around it's not visible to others what i'm doing xD
If you want to be hardcore, get a pair of shoes, cut off the heel on one of them, stick the chip and coil in a fake bottom casing that doesn't impede the metal detector, and make the wire with the notification thing (light, sound) long enough to go up your pants and into your pocket or wherever you want.
Then you can just walk around like a gangster and scan things without anyone knowing.