Hi Unlucky here is a web forum which will help you
locate the info. that you need about making a home
made pin pointer, just get ready to spend some time
there searching for the schematic.
Contact Carl @ the Geotech forum he is also member of
this forum to
I'm going to go with Drodda here, the Centech ones work and theyre only about $16. Unless its on the technical "cool I want to try that!" side, on which I totally agree doing stuff like that is neat!