Home made deep metal detector

[RedRook]

I think I'm going to try to make this.
http://www.geotech1.com/cgi-bin/pages/c ... /index.dat

This is a special kind of metal detector made for objects larger than a coke can several feet under the ground. Other kinds are made to penetrate several inches.

It looks like I can get all the parts for about $70 if I etch my own circuit board and make good use of pvc pipes, and that isn't bad considering this style of detector can go for $750 on the cheap side. It'll be a while till I can really dive into it since Radio Shack doesn't seem to carry all of these components. Maybe I'll start one of the simpler ones that costs $20 in components if I don't rush by overpaying at RadioShack. This seems like an extremely simple design, but it looks like it is made to penetrate 2-4 inches.

http://makezine.com/projects/treasure-finder/

This could be fun. It might lead to some experimentation like larger home made coils if I do this myself, and I won't have to be so heart broken if I break it. I can just rebuild it.

I might even get more adventurous and eventually try to make my own earth resistivity meter for the fun of it.

http://www.geotech1.com/cgi-bin/pages/c ... /index.dat

If I stop posting, I've quite possibly electrocuted myself. Has anyone played around with a metal detector in any abandoned places? Have you found anything?

[cdevon1200]

may be better off going this route.

http://www.geophysical.com/

[RedRook]

It's a good suggestion, but ground radar is expensive. It also looks like most of these are using either x-ray or microwave frequencies, which I'm much more nervous about playing with than low frequency radio waves.

Then there is the problem about complexity. The simple metal detector I linked to is about the difficulty of a normal cake. The other ones are probably closer to a wedding cake. The radar with 3D imaging is closer to building a new couple's first house.