Metal Detector Experiments

I mentioned a while ago that I was seeking to break through what I call the "20 cm limit" of metal detectors. Above all, that refers to IB detectors. There is also a limit that I call the "10 cm limit". This applies to BFO detectors. I therefore designed and built a digital "20 cm limit" metal detector. Digital was not a good choice, it turned out. However, when I applied a radio technique to the detector, this improved detection by a quantum leap. This looks promising. The relative improvement was huge. OBSERVATION: I now need to exhaust my digital experiments, to see all that they indicate. Then I'll repeat with analog.