Can a Metal Detector Discover a Hidden Treasure in Your Yard?

A metal detector is great for finding hidden treasures in the ground. Although they are enjoyed by children and adults alike, they are also used by professionals. Archeologist's use metal detectors for scanning ancient archeological sites searching for metallic type items. They are also used by surveyors to detect various grades of subsurface metal ores that are unseen with the human eye.

Metal detectors are designed on the principle of electromagnetism, which basically uses electromagnetic fields to detect the presence of metal objects.

There are several different models available to accomplish locating metals, such as the induction balance detector, the pulse induction detector and the frequency oscillator detector.

The induction balance system was the biggest technical change in metal detectors. Here is where two coils are set up in an electrical equilibrium to create a 'zero' balance. When varying forms of metal are introduced into the vicinity of the coil, it will cause an unbalance, which in turn, will produce a different type of tone into the detectors' speaker.

The pulse induction detector infiltrates the deepest, but because it detects every piece of metal in the ground, it cannot distinguish the difference between the targeted object and bogus materials.

Using a beat frequency oscillator detector, a coil is used as an inductor within an oscillator, which will cause the frequency to change whenever metal causes it's inductance (the ratio of change in electrical current) to change.

The basic parts of all detectors are a control box, a shaft and a search coil. These will include the battery, coil and the electronic unit itself. For the most part, the coil, acting as a transmitter, is the most important part of the metal detector.