The authors provide a comprehensive look at nearly every significant detector architecture:

: Detailed guidance on coil types, performance comparisons, and physical construction techniques. Inside the Metal Detector: Moreland, Carl - Amazon.com

Given the specific nature of your search keyword, here is practical advice:

George Overton is a legendary figure in the metal detecting community, primarily known for his innovative designs. Unlike Very Low Frequency (VLF) detectors, which rely on continuous sine waves, PI detectors send short, powerful bursts of current through a search coil.

The authors manage a difficult balancing act. They discuss complex electromagnetic theory and math (including differential equations for the signal decay), but they maintain a conversational tone.

The .pdf work you are searching for typically runs 50–70 pages and is structured like a technical textbook. Here is a breakdown of its core chapters:

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