This article is about coils and what to expect from them. Anyone who has been with this hobby for a few years has found out some of this by themselves, the hard way. I hope to save you the expense by advising you to choose coils wisely.

The reasons that you may want to use a smaller coil like a 4 or 5 inch one would be that you are hunting in a site that is cluttered with metal trash. One fact that the manufacturers won't tell you is that using a mid sized or large coil in places like that will only cause a target overload condition that will mask out signals. It will mean that you will not be able to find those good targets that lie closely to other metal objects. When you discover that you are hunting in a situation like this please don't blame the manufacturer. All metal detectors will work for clean conditions but have different effects in trash. Some may have better discrimination or have the capability to signal you that you have multiple targets under the coil. Each one is but a tool and has its strong point and weak points.

To effectively hunt the trashy sites then use a small coil and if you are still having difficulty then lower the sensitivity. Using this method you can selectively move around trash to read individual targets that would be masked out by a larger or medium coil.

One more thing, as far as advise goes, then take this to heart, don't play mind games and expect miracles from your detector. Some advertisements are truly out of this world! Ignore all the endless claims for the super deep machines. Most coins are less than 5 inches deep anyway. Some machines will perform better at greater depths but find that out for yourself by air testing them at the shop. Regardless to comments to the contrary, air tests will give you a lot of information.

Most people have wanted greater depth with their machine sooner or later. They generally fall for the advertisements to buy bigger coils. Some of these coils are labeled with extravagant names but the truth is that a larger coil will generally give you an inch or two at maximum. My experience was just over one inch improvement in depth, however, you will loose the ability to find the smaller targets! Do not forget that many of these targets that are marginal with your eight inch coil may be ignored by the large coil and the masking effect will be much greater.

When you become dissatisfied with your detectors depth it is a better thing to advertise your detector on a classified forum for sale and then apply the money to a better, deeper detector.

One more word on the smaller coils, they are addictive but beware! They will not cover the area that you are used to covering. Sure they are fun to use in the trash to pull those old coins but your finds may fall because you will only be able to cover a small fraction of the area that you did with an eight inch coil.

You should consider that if you choose to use the smaller coil on new large area hunts like relic fields then you must realize that you will need to return and have access for a prolonged period of time. If you are limited in time or permission on large sites then use a medium sized coil for more coverage. You want to pull more of the good targets faster and cover most of the area the first time that you visit the site. If you have permission or time to return again then cleanup with the small coil in the trashy areas.