How to build a Surf PI 1.2 pulse induction metal detector from a DIY kit. | Be cheap and DIY:
Prepper Geiger Counter - Ken's Schematics
Metal detector
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Schema Barracuda PI Ver.1.1 | PDF
Detector de metales, Detectores de oro, Metal
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PI metal detector for deep searching | video recording, video recording, metal detector | Little video how work this detector. The coil is small 27 cm diameter, but detector can use various