Metal detecting is much loved and appreciated worldwide as a personal hobby pursuit, and the same technology is also used by security services and armed forces. On a personal level, from young to old, there is nothing more exciting than listening intently to the detectors
All this is based on the power of electromagnetism. it has been said that electricity and magnetism are like an old married couple', where ever you find one, the ether is certainly not too far away. Magnetism ultimately helps create electricity and electricity helps create magnetism, this is how closely they are linked. Electricity always comes from a powered generator, regardless of the source of power, the generator is essentially a large drum of copper wire, when this wire moved at high speed through a magnetic field it creates electricity. The electricity motors we use every day for example even the simple electric motors that power our household appliances run on the reverse of the generator concept. When electricity is introduced into the electric motor it changes the magnetic field in a coil of wire thus making it spin. So, it really is a case of Yin and Yang.
You use electricity to create magnetism and magnetism to create electricity. When you have a changing electric field you invariably have a changing magnetic field, and this is how we can begin to understand how metal detectors work.
So how does all this magnetism and electricity make a metal detector work?
The basic design of a metal detector has a round transmitter at the end of a handle. This transmitter has a wire coil inside it, and when electricity enters this coil it creates its own magnetic field. As you move this transmitter (we'll be recommending later in the article that you develop a ‘Low and Slow' sweeping movement) you'll also be moving the magnetic field. If the transmitter moves over a metal object, the magnetic field from the transmitter causes another magnetic field to appear around the metal. This is the magnetic field that the detector picks up. The metal detector usually has a second smaller coil in its head called a receiver coil that's connected to an audio speaker. This is how it is possible to accurately hone in on the exact location of the buried metal. The closer the transmitter coil or the head of the detector comes to the piece of metal, the stronger the magnetic field becomes and thus the stronger the magnetic field in the receiver coil the louder the noise as more current flows in the loud speaker.
Now that we know the basic science behind the metal detector, how do we get the best results from it First off, read the instructions. Each and every metal detecting model has its own very specific set of instructions and handling guidelines. It is very easy to rush into things, just open the box and head out to your local park but please take the time to know your settings as it will save you lots of time and frustration and quickly make your metal detecting experience much more enjoyable and rewarding.
It's all in the hips! Low and Slow!
The way in which you swing your metal detector is just as important as getting to know your instruments settings. A 'Low and Slow', approach is universally recommended. It is very important to keep your detector low to the ground without actually hitting it. The lower to the ground we hold the transmitter head then the better chance we have of the magnetic field penetrating and deeply as possible into the ground. As well as getting used to a low sweeping left to right motion it is very important to do it slowly. if you are moving the head too fast over objects you do not give the system time to create enough of a magnetic disturbance, especially in smaller objects and as a result you'll have covered ground and missed an opportunity for detecting an object.
Many seasoned detectors will tell you that location is everything in having enjoyable and rewarding time with your detector, so make a plan and do some research! It’s very important to get into the mindset of... where would items containing metal be lost. Get to know your local area and think along the lines of where do people congregate whether it be picnic areas or play grounds etc. it is always amazing how simple coins or pieces of jewelry can inadvertently get lost where there is movement of people. It is very important to know your local laws with regards to metal detecting and never trespass on private property without consent from the owners. But looking up old survey maps my give indication to the location of old houses, industrial buildings or farm yard out houses. Sites like these can be a treasure trove of old artifacts.
The one and everlasting favorites location for millions of enthusiasts is the beach. Considering the sheer volume of people who go to the beach in summer-time and more than likely change their clothing whilst there... well it's a near guarantee that you find some recent coins and jewelry to say the least. Not to mention the intoxicating allure of finding some pirate silver coins that may have been washed ashore from a sunken galleon many eons ago. Another surprising tip for the beach is to re scan holes you have dug. It has been recorded many times that the ocean can create pockets of items from its tidal action and items may actually be stacked in several layers. 80 it's very good practice to re-scan after your initial dig.
Finally, it always pays off in the long run to maintain and clean your metal detector. Always clean if off with fresh water to avoid long term soiling or possible rust corrosion from saint if you were using it at the beach. Were necessary use a lubricant on those moving parts.