Ran across this yesterday

[silverdog]

found this, its in Polish but google translate helps

[King Karl]

I had a electronics magazine named "elrad" a few years ago. There was a complete instruction in it, so I build one. As far as I can remember this detector was passable in function. Could find iron objects very well, copper and gold wasn´t that well. The reaction commonly a bit lazy. I think that can be improved ?

[bernte_one]

http://www.lucaslab.grandhost.pl/lucaslab/wykrywacz_PI.htm

[silverdog]

it was lucaslab, i did build one and had boards for a while
it was ok but not great, had a horrible sound as well
there are certainly better projects around

[6666]

I carnt remember the original name for that circuit but Silverdog used to sell the pcb.

It was Lucus Lab or something like that.

[porkluvr]

Component values are different but otherwise looks almost exactly same as the ProScan, for which there is a project page here.

[6666]

I carnt remember the original name for that circuit but Silverdog used to sell the pcb.

[geoscash1]

Anyone know anything about this PI or has anyone built it? are there pcb files anywhere for it?