What is Ground Balancing?
The amount of minerals in the soil varies from location to location. Sometimes the composition of minerals change within a small amount of area. Other locations, the mineral composition in the soil will be fairly consistent over a large area. The type of minerals contained in the soil will also vary according to location. For instance, one of the more common minerals present in soil is iron, and some areas of the country have high concentrations present.
Without some method of "ground balancing", the metal detector would be detecting all the minerals present in the soil, therefore not seeing through them, an thus, small or deeper targets would not override the signals produced by the minerals. In extremely mineralized soil, the metal detector would hardly be able to detect a target laying on the surface of the soil.
Ground balancing the detector is simply, the term used to describe the function of adjusting the metal detector to ignore the minerals in the soil so that they are not detected by the metal detector.