A metal detector can have many different uses, from searching for gold and buried treasure, to looking for contraband guns and devices at airport security. In recent years metal detectors have become more common and people will travel to all parts of the world hunting for precious metals, but rarely getting it.
A metal detector is made up of a number of different parts, including a stabilizer, a control box, a shaft and a search cell. The stabilizer is designed to hold the detector and stop it from vibrating away from you when you move it from one side to the other. The microprocessor, speaker, batteries and circuitry are all in the control box. The control box and the coil are connected by the shaft, which can sometimes be adjusted to suit your needs. The part of the metal detector that actually senses or finds the metal is known as the loop or the search head.
Some metal detectors have a jack that can be used to connect to headphones and on some detectors the control box is below the shaft and there might be a display unit above it. Depending on which one you use, it may work on low frequency, beat frequency oscillation and pulse induction. Probably the most popular metal detector is a very low frequency one that people use to search for gold or other precious metals; on this type of detector there are two coils.
Some detectors work on transmission cells and some on receiver cells. In the transmission models electricity is sent along a coil loop, first in one direction and then the other. The unit’s frequency is determined by the number of times the current switches between each side. In the receiver cell the coil loop acts as an antenna to pick up frequencies that come from the ground where the metal might lie.
A metal detector uses what is known as a VLF pulse which tells one metal from another by what is known as phase shifting, which is the difference between the target’s frequency and the transmitter’s frequency. The detector either emits a tone, or a light comes on in the display unit giving you information on the different types of metal.
The way in which detectors work means they can pick out what might be gold from a base metal. Beach hunters along the Jersey shore have made some amazing discoveries with metal detectors and every day someone else is out there hoping to make their fortune with a metal detector. People also hunt for coins and while some have been found, there are no guarantees.
Most people who use a metal detector do so for the sheer enjoyment of doing it, if they find something of value while they’re out there, then that’s just the icing on the cake. Beach hunters and others who go out regularly with their detectors refer to some places as hot spots, i.e., places where they are most likely to get a hit and find something valuable.
You can buy a metal detector quite cheaply or you can go for a top of the line model that could cost you hundreds of dollars. Be wise in your choosing though as some are definitely better than others.