VLF means Really Minimal Frequency and is similar engineering Utilized in detectors built for coins, jewelry, and relics. VLF detectors broadcast at frequencies measured in kilohertz starting from 3 kHz to 70 kHz. Here's 5 main reasons why you may decide on a VLF over a PI The neatest thing http://leydis16.phorum.pl/viewtopic.php?p=1026053#1026053