VLF means Very Very low Frequency and is identical know-how used in detectors constructed for coins, jewelry, and relics. VLF detectors broadcast at frequencies measured in kilohertz starting from 3 kHz to 70 kHz. Listed here are 5 explanation why you might go with a VLF about a PI In https://ccn.dynamics365portals.us/forums/general-discussion/2977a2c7-8ef6-f011-ad8f-001dd8050036