VLF stands for Quite Lower Frequency and is identical technological know-how Utilized in detectors created for cash, jewellery, and relics. VLF detectors broadcast at frequencies calculated in kilohertz starting from 3 kHz to 70 kHz. Here's 5 explanation why you would possibly select a VLF over a PI So, the http://leydis16.phorum.pl/viewtopic.php?p=1041999#1041999