I don’t know how it works either, and have never tried it myself, nor seen it done. Yet my FIL and my stepdad did it extensively, both for water and for underground pipes. I think Bushrat has used it on pipes, need to ask him later.
My stepdad (in Australia) used it to help many people. One was a station (ranch) owner whose stock were dying from drought; stepdad found water to drill for and saved the place.. Second, was my parents’ lawyer who purchased an antique “Queenslander” bungalow and wanted to move it to a hilltop with gorgeous view. But, no water available according to the “experts”. My stepdad came and found it… Two very happy people.
Tweva, can you please give instructions for newbies like myself? Thanks!