The device that is used to look for metal items buried deep in the ground is called a metal detector. It operates on battery power to produce a magnetic field that can pass through the ground and magnetize metallic items that are situated under it.
It has a part called a receiver which is a range of sensitive wires that react to the magnetized metal item. Once the metal object reacts to the device, it conveys a signal by means of a speaker which releases a tone to notify the user of the existence of the metal item.
Metal detectors are still employed in industries ranging from transportation to construction industries. They are also purchased and used by hobbyists or serious treasure hunters to search for coins, gold, and jewelry at notable areas, parks, and beaches.
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Features of a Metal Detector
Metal detectors have a range of features, with every feature meant for a particular purpose. This article will further discuss how to choose a metal detector by helping you understand how each feature works, and how they contribute to the overall functions of the detector.
The coil is the part that is deemed the most fundamental part of a detector. It sends magnetic fields below the ground to magnetize metal items, and in turn, makes those items noticeable by the receiver. There are also coils that are specially-designed for water usage.
VLF or Very Low Frequency is a versatile kind of coil technology that can be employed in the earth or shallow waters. Single-frequency VLF detectors utilize a single, secure working frequency, while multiple-frequency VLF detectors make use of several frequencies, subject to the type of metal being searched.
Size of Coil
The depth of a detector’s exploration is comparable to the search coil’s diameter. Bigger coils generate a bigger field of exposure, while tinier coils tend to generate smaller electromagnetic fields. The field’s size is also comparable to the object’s size that is visible. A bigger coil might miss tinier segments of metal.
Smaller coils that are 6 inches or less are recommended for searching in locations with pieces of debris or smaller nuggets of gold. Coils that measure 7-9 inches are ideal for versatile hunting due to a wider range of coverage, while coils that measure over 9 inches are meant for bigger items or for deep-rooted explorations.
Pulse induction detectors are not as widely used as standard VLF models. They are recommended for exploring deep waters, or deeper fields. They are not particularly sensitive to ground interference or tinier chunks of gold, but they are beneficial for the ground with a high level of mineralized content.
Target ID determines the metal item that has been distinguished, which lets users decide whether or not they want to excavate the object.
A majority of detectors feature target ID categories that distinguish quarters, copper pennies, iron, foil, pull tabs, dimes, or quarters. Some have a target ID that is capable of disregarding particular items or metallic content.
Several detectors release a variety of audio sounds subject to the conductivity of an identified item. For example, foil or nickel items might generate low-pitched sounds, while nails or screw caps might provide medium tones.
Several detectors can work in a variety of modes. The most common are the full-discriminate mode, all-metal, tone discriminate, and pinpoint.
Full-discriminate means the majority of refuse is instantly overlooked, while all-metal mode means all kinds of metals are perceived.
Tone discriminate mode releases a distinctive dual sound and instantly casts off the iron, while pinpoint mode translates to lining up the center of the item perceived with the center of the coil’s range and allows the user to find the target item exactly.
A metal detector’s frequency is itemized in kilohertz or kHz, and it indicates the number of times a signal is conveyed and obtained by the detector every second. A variety of frequencies are ideal for perceiving a varying selection of items.
A majority of detectors work at lower frequencies, which offer greater sensitivity to silver and copper, plus it provides greater detection depth. Meanwhile, higher frequencies are more sensitive to natural gold products and smaller metals.
However, since they do not discriminate between iron and other kinds of metals, they are often used by gold prospectors.
Low Battery Indicator
Detectors typically work on 9-volt batteries, and it is advantageous if a model has an indicator light to notify users when the power of the batteries is getting low. Careful hunters often take along extra batteries with them just in case.
Users should change batteries as soon as the indicator light comes into view. A lower range of power can definitely affect the accuracy of a detector.