Digital Metal Detector

An IB metal detector I designed keeps entering or re-entering the charts on my blog. I merely suggest improvements to the original here, and these have more than 4 000 views to date. With this design, I revolutionised IB (Induction Balance) metal detectors, by removing analogue electronics, and replacing them with digital -- or should I say, Schmitt Boolean logic. Before this design came along, IB typically used 50-100 components. I reduced that to, say, a third. OBSERVATION: This was a popular design. It went into production, too, in two versions that I know of. My design work has, incidentally, been very useful to my philosophy, particularly with regard to the relationship between theory and reality (which is not the same).