Metal detectors have evolved significantly over the years, and nowadays, there are various types of metal detectors to choose from. The right metal detector for you will depend on your specific needs, including the environment you’ll be using it in and the type of targets you’re looking for.
In this article, we will explore the different types of metal detectors available in the market, their features, and the type of detecting they are best suited for. With this knowledge, you’ll be better equipped to choose the best metal detector for your needs.
Very Low Frequency (VLF) Metal Detectors
Very Low Frequency (VLF) metal detectors are the most common type of metal detector and are commonly used by hobbyists. These detectors work by transmitting a low-frequency magnetic field into the ground.
When the field comes into contact with metal, it induces a small electrical charge, which is picked up by the detector's receiver coil. The detector then produces an audio signal to alert the user of the metal's presence.
VLF detectors are effective at detecting a range of metals, including coins, jewelry, and relics. They can also be used to discriminate between different types of metal and filter out unwanted signals.
Pulse Induction (PI) Metal Detectors
Pulse Induction (PI) metal detectors are another type of metal detectors that work differently than VLF metal detectors. While VLF detectors use two coils, one for transmitting and the other for receiving, PI detectors only have one coil that works for both transmitting and receiving.
They are typically used for deep metal detecting in highly mineralized soil or in water. PI metal detectors work by emitting a pulse of magnetic field into the ground, which then bounces back to the detector after hitting a metal object.
PI detectors can ignore minerals in the soil, which makes them ideal for beach detecting or gold prospecting. However, they are not as good at discriminating between different types of metal objects as VLF detectors
Beat Frequency Oscillation (BFO) Metal Detectors
Beat Frequency Oscillation (BFO) metal detectors are one of the oldest types of metal detectors and were invented in the 1930s. They use a simple technology where two oscillators are used to create a beat frequency.
One oscillator operates at a fixed frequency, while the other is tunable. When the two frequencies combine, a beat frequency is produced that can be used to detect metals.
BFO detectors are less expensive than VLF or PI detectors, but they are also less sensitive and have a harder time differentiating between different types of metals. They are best suited for use in areas with low mineralization, and are often used by beginners who want to start metal detecting on a budget.
Multi-Frequency (MF) Metal Detectors
Multi-Frequency (MF) Metal Detectors are a relatively new technology that allows the detector to transmit and receive multiple frequencies simultaneously.
This provides the ability to detect a wider range of targets and can be particularly useful in areas with high levels of mineralization or where there are multiple types of metals.
Multi-Frequency metal detectors are becoming increasingly popular, especially for serious treasure hunters who want the most versatile machine possible. They tend to be more expensive than VLF or PI detectors but can provide greater accuracy and depth of detection.
Industrial Metal Detectors
Industrial metal detectors are used in manufacturing facilities to detect and reject metal contamination in products such as food, pharmaceuticals, plastics, and textiles. These detectors are highly sensitive and can detect even the smallest pieces of metal.
They are typically installed in production lines and use electromagnetic fields to detect metal. When metal is detected, the metal detector sends a signal to a reject mechanism that removes the contaminated product from the production line.
Industrial metal detectors can be customized to meet specific manufacturing requirements and are designed to be durable and withstand harsh production environments.
Walk-Through Metal Detectors
Walk-through metal detectors are commonly used in public areas to detect metal objects that people may be carrying with them, such as weapons or other contraband. These metal detectors are often seen in airports, government buildings, courthouses, and other locations where security is a concern.
Walk-through metal detectors work by emitting a magnetic field and then measuring any disruptions in that field caused by metal objects. If a metal object is detected, an alarm will sound or a security agent will be alerted. These detectors are an important tool for maintaining security in public areas.
Underwater Metal Detectors
Underwater metal detectors are designed specifically for detecting metal objects beneath the surface of water. They are used in a variety of applications, including shipwreck exploration, treasure hunting, and underwater construction projects.
Underwater metal detectors typically use pulse induction technology, which allows them to function effectively in saltwater environments. They may also feature waterproof or submersible designs, allowing the user to fully immerse the detector in water while in use.
Some models may also be equipped with specialized search coils or other features to help improve detection accuracy in underwater environments.
Gold Prospecting Metal Detectors
Gold Prospecting Metal Detectors are specially designed to detect small gold nuggets in mineralized soil. These detectors are highly sensitive to small gold particles and are designed to operate at high frequencies.
They are often equipped with advanced features such as ground balance, iron discrimination, and multiple search modes.
Gold Prospecting Metal Detectors are available in various types, including Very Low Frequency (VLF), Pulse Induction (PI), and Multi-Frequency (MF) detectors. VLF detectors are ideal for finding small gold nuggets, while PI detectors are more sensitive to deeper targets.
MF detectors, on the other hand, are versatile and can be used for both gold prospecting and general metal detecting.
Gold prospecting metal detectors are used by both amateur and professional prospectors, and they are commonly used in gold-rich areas such as Australia, Africa, and the United States.
Some of the most popular models of gold prospecting metal detectors include the Garrett AT Gold, Minelab GPX 5000, and Fisher Gold Bug Pro.
Frequently Asked Questions - FAQs
How do metal detectors work?
Metal detectors work by generating an electromagnetic field which detects the presence of metal. When a metal object is detected, the detector produces a signal, alerting the user.
Can metal detectors detect all types of metal?
Most metal detectors can detect a wide range of metals, including iron, copper, aluminum, and gold. However, certain metals, such as stainless steel, may be more difficult to detect.
What is the best type of metal detector for beginners?
Very Low Frequency (VLF) metal detectors are generally the best choice for beginners. They are easy to use, versatile, and relatively affordable.
How deep can a metal detector detect?
The depth at which a metal detector can detect metal depends on a variety of factors, including the type of metal, the size of the object, and the sensitivity of the detector. In general, most metal detectors can detect objects at depths of several inches to several feet.
Can metal detectors be used to find gold?
Yes, certain types of metal detectors, such as gold prospecting detectors, are specifically designed to detect gold. These detectors typically use high-frequency VLF technology or pulse induction technology.
Are metal detectors waterproof?
Some metal detectors are waterproof and can be used for underwater metal detecting. However, not all metal detectors are designed for use in water, so it is important to check the manufacturer's specifications before using a metal detector in or around water.
Are there any legal restrictions on metal detecting?
Yes, there are legal restrictions on metal detecting in some areas. For example, it may be illegal to metal detect on private property without the owner's permission or on certain public lands. It is important to research the laws and regulations in your area before using a metal detector.
How do I choose the right metal detector for my needs?
When choosing a metal detector, it is important to consider factors such as the types of objects you will be searching for, the conditions in which you will be using the detector, and your level of experience. It is also important to consider your budget and any legal restrictions in your area.
Conclusion
There are various types of metal detectors available for different purposes. VLF, PI, BFO, and MF metal detectors are popular among hobbyists, while industrial and walk-through metal detectors are widely used for security purposes.
Underwater and gold prospecting metal detectors are designed for specialized use cases. Each type of metal detector has its advantages and limitations, and it's important to consider the intended use case and environment when selecting a metal detector.
