VLF stands for Incredibly Minimal Frequency and is the same engineering Employed in detectors created for coins, jewellery, and relics. VLF detectors broadcast at frequencies measured in kilohertz starting from three kHz to 70 kHz. Listed below are five explanations why you would possibly choose a VLF about a PI http://gzew.phorum.pl/viewtopic.php?p=614391#614391