When the coil passes over metal, the inductance changes, altering the audio pitch. BFO is highly sensitive to temperature drift and lacks depth. Key Engineering & Design Concepts
Uses two distinct coils—a transmit coil and a receive coil. Inside The Metal Detector George Overton Carl Moreland.pdf
The book breaks down the different technological evolutions of metal detectors, each suited for different environments and targets. Overton and Moreland explore the mechanics of four major categories: 1. Beat Frequency Oscillator (BFO) When the coil passes over metal, the inductance