VLF (very low frequency) detectors send a steady signal into the ground. Gold detectors of this type run at a high frequency, like 61 kHz on the Gold Finder 2000 and Gold Kruzer, which makes them very sensitive to small gold near the surface. They are lighter and cost less.
Pulse induction (PI) detectors send short, strong pulses and listen for the echo. They are much less disturbed by mineralised, iron-rich ground and hot rocks, which is where VLF detectors struggle. The Magnetar 9000 is Nokta's pulse induction gold detector.
Choose VLF (Gold Finder 2000 or Gold Kruzer) if: you are starting out, you look for small gold near the surface, you work alluvial ground and rivers, or your budget is limited. The Gold Kruzer is fully waterproof, so it is the one for river work.
Choose PI (Magnetar 9000) if: you work hard, red, mineralised ground, you are after bigger and deeper gold, or other detectors in your area keep giving false signals.
Many serious miners own both: a PI detector for depth and a VLF detector for small gold and for checking the material from the pit.
