12V Battery → Boost Converter (50–150V) → MOSFET Switch → TX Coil ↓ Damping Resistor ↓ RX Coil → Preamp (x100) → Bandpass Filter → Integrator → Comparator → Audio/Display
This is where "high power" meets "high sensitivity." After the pulse ends, the coil voltage drops to zero, then a tiny secondary voltage appears—the target echo . high power metal detector circuit
+150V │ └───┤ TX Coil (L1) ├───┐ │ MOSFET (IRF840) ──────────┤ Drain Gate ← 555 / µC pulse │ Source ───────────────────┘ │ Fast Diode │ GND 12V Battery → Boost Converter (50–150V) → MOSFET
For a hobbyist seeking maximum depth, the Pulse Induction (PI) architecture is the recommended path. Below is an overview of the critical stages required to build such a circuit. To optimize a metal detector for depth and
To optimize a metal detector for depth and sensitivity, engineers focus on several variables:
A high power circuit is the only choice for "diving detectors." Pot the entire circuit board in epoxy or silicone sealant and house it in a PVC tube.