Finding some treasure is very exciting. A lot of people are opening for themselves metal detecting hobby and finding very interesting stuff underground. Those things might include some coins, pieces of jewelry, and knives. But if you are just a beginner you might think – how does it actually work?
A metal detector is a device that can locate the metal things at some distance. If you are already not a newcomer and know something about metal detectors we recommend checking this top 10 best metal detectors review by Detect History. You might find there the best devices for your hobby and choose the best for your purposes.
When was the metal detector created?
The very first metal detector appeared on the date of shooting of US President James A. Garfield on July 1881. One of the bullets was stuck in the body of the President, and nobody among the doctors could find it. Well-known Alexander Graham Bell promptly created an electromagnetic metal-locating device called an induction balance. However, this device was based on an earlier invention of German physicist Heinrich Wilhelm Dove. Even when the bullet wasn't found, and the President later died, Bell's device did work correctly, and many people consider it as the very first electromagnetic metal locator.
How does the metal detector work?
Metal detectors work is based on electromagnetism. Each metal detector contains a coil of wire (wrapped around the circular head at the end of the handle) known as the transmitter coil.
When you move the metal detector over the ground or sand, you make the magnetic field around the surface. If you move the detector over a metal object that is located on the ground or sand, the moving magnetic field affects the atoms inside the metal and changes the electrons way of moving. In easier words, the metal detector creates electrical activity in the metal. And when you move a metal detector over a metallic object, the magnetic field that is created by the detector causes another magnetic field to appear around the metal object.
After that, the metal detectors pick up this field created around the metal object. The metal detector has a second coil of wire in its head (its name is receiver coil), and it is connected to a loudspeaker. So, as you move the detector over the metal, electricity flows through the receiver coil, making the loudspeaker click or beep.
How deep can metal detector go?
The answer to this question is not so easy, because it depends on various aspects.
The size, shape, and type of the metal item located underground: bigger things are easier to locate at depth than small ones. Also, not all metal detectors can detect gold. For that, you will need a special gold metal detector.
The orientation of the object: objects buried flat are generally easier to find t because it makes the buried object has a bigger surface and is more effective at sending its signal back to the detector.
The age of the object: things that have been buried a long time are more likely to have oxidized or corroded so the signal to the metal detector will be worse, and they are harder to find.
The ground or sand you are searching in.
In general, metal detectors can locate the items that are buried around 50-80 cm in depth.
So the metal detector work is based on the electromagnetism and will help you to locate the items that can be quite deep inside the soil or sand. There different factors that allow finding the objects, but the bigger flat objects are much easier to locate for mostly all types of metal detectors.