Detecting Terms
Coil Size..... The size of a search coil can influence the detection depth and sensitivity of a detector. The larger the search coil, the deeper it tends to detect into the ground; but with less sensitivity to very small targets. The smaller the search coil diameter, the more sensitive it becomes to small targets, but with reduced detection depth.
Conductivity..... Conductivity refers to how well an object in the ground allows electrical current to flow through and around it. If the current flows freely around the object when it is energised by the electromagnetic field from the metal detector it is described as a highly conductive target.
Discrimination..... Discrimination is a metal detectors ability to identify buried targets based on conductivity and or ferrous properties. Based on measuring these properties, it is possible to determine valuable targets from junk targets so you can spend more time digging valuable targets.
Electromagnetic Field..... An electromagnetic field is a physical field produced by electrically charged metal objects. This refers to both the transmit field from the detectors search coil and the receive field from the target.
Ferrous..... Ferrous objects or targets contain Iron and therefor are attracted to a magnet, for example - horse shoes, nails, tin cans, nuts and bolts. Many natural and man-made objects contain Iron, most of these are junk, however some can be valuable relics.
Frequency..... The frequency of a metal detector refers to how fast it sends signals into the ground. Frequency is measured in Hertz (Hz). Certain frequencies detect targets better than others; for example high frequencies find very small targets while low frequencies find deeper large targets.
Ground Mineralisation..... Ground Mineralisation refers to the naturally occurring minerals in the ground that effect a metal detectors performance. There are two main types of ground mineralisation, one is due to Iron particles and the other is due to salt, such as salt water beaches. Iron particle mineralisation cases the ground to become magnetic and salt mineralisation causes the ground to become more conductive. Both forms of ground mineralisation can produce false signals and mask good targets.
Noise Cancel..... Noise cancel is a metal detector feature that shifts a metal detectors frequency or frequencies to reduce the effect on the electromagnetic noise from sources such as nearby or overhead power lines, cell phone towers and even other metal detectors being used nearby.
Non-Ferrous..... Non ferrous materials do not contain iron. Good targets include coins, gold rings, and copper artefacts. Junk targets include bottle tops, pull tabs and aluminium foil.
Target..... Target refers to any metal object that can be detected by a metal detector. A target can be either valuable, such as a coin or gold ring, or junk such as a bottle top.
Target ID..... Target ID numbers and audio tones are produced by a metal detector to enable you to identify targets based on their conductive and/or ferrous properties.
Threshold..... Threshold is the continuous sounds used to listen for a target signals. The threshold will "blank out" to indicate the detection of a discriminated/rejected target.