Metal detectors work by transferring an electromagnetic field from a search coil to the ground. If a metal object falls under the electromagnetic field relayed by the metal detectors, the metal object in the ground becomes energized and transmits its own electromagnetic field.

Metal detectors can identify buried items on the basis of their transmission and ferrous properties. This is called the discrimination ability of a metal detector. There are four main types of discrimination in Minelab metal detectors. The simplest type is variable discrimination that utilizes a control knob to adjust discrimination levels.

As a valuable item is found, an audible response by the metal detector alerts the user. There are several Minelab metal detectors that can visually display information about the target like ID numbers and 2D display.

Listen to this episode to learn how metal detectors operate.