How To Use A Metal Detector

How To Use A Metal Detector Like An Expert Detectorist

So, you’re interested in the hobby and you just bought your first metal detector, but you don’t know where to start.

Is there a right technique for sweeping?

Do all metal detectors work the same way?

How do you maximize a metal detector’s performance?

We’ll go through each step to using a metal detector, so bad habits don’t become techniques that can diminish performance and results.

To get a head start on how to do it right, swing this way.

How Does a Metal Detector Work?

Briefly, a metal detector transmits an electromagnetic field into the ground from the searchcoil. Any metal that is within this magnetic field responds in kind with a magnetic field of its own that travels in eddy currents. The searchcoil senses and receives this data and processes this signal into a response for the user to interpret through audio, visual, or vibration alerts.

How to Use a Metal Detector

Every metal detector provides the same results – metal detection. The technology may be the same between different models, but its effectiveness, additional features, and user settings will vary, and this can have an impact on performance, detection depth, and suitability for hunting in various terrains.

Because of these differences and manufacturer patented technology, each metal detector will be slightly different, so it’s essential that you get to know your metal detector. This can be done by reading the user manual, watching online tutorials and user experiences, and of course, getting out there and using it yourself.

Here’s a general guideline on how to get a quick start with a metal detector.

1. Assemble the Metal Detector

Assembly is different for every detector, but the main idea is to attach the searchcoil to the lower shaft, assemble all shafts, attach the armrest, and connect and wrap the coil cable.  Look to your user manual for specific instructions.

2. Power On

Typically, the Power On button also functions as Power Off and Factory Reset.

3. Select the Detection/Search Mode

If you have a basic, entry-level detector, it may already default to its primary search mode which is usually an All Metal type mode. For detectors with multiple search modes, you’ll have to select the one that best suits the terrain for where you’re currently hunting. Many detectors may also power on to the last mode that you previously used before switching it off. Selecting search modes and making adjustments may be done with knobs and potentiometers or with buttons on a digital visual display.

4. Select Advanced User Settings

If your detector is an entry-level model, it may already have preset user settings that are not adjustable, so this step may not apply. Usually this step involves automatic or manual ground balancing, setting noise cancel or the threshold, setting discrimination (if applicable), and adjusting sensitivity.

5. Get Detecting!

There may be a dedicated button to exit all the menus you’ve just accessed, but the goal is to get to the main, primary display that should have Target ID, DISC segments, depth indicator, etc. all on the same screen.

Beginner detectors may be even easier to quick-start as it may only consist of powering on and getting out in the field. This may be due to the fact that there are minimal search modes (1-2), preset or automatic ground balancing, and sensitivity may be set to a default setting. That’s it!

Key Metal Detector Features

Whether they’re preset or automatic, all metal detectors share these key metal detector features. Here’s a brief on how they work and why you need to know about them to maximize detection performance.

1. Sensitivity

This is the detector’s ability to pick up the smallest targets, metallic substances with the weakest electromagnetic fields, and to adjust a detector’s ability to respond to various factors in the environment. Running it “hot” means running your detector with maximum sensitivity that may work well for experienced users, but it also means a detector can get “noisy.” For example, detecting hot may allow you to hear more weak signals from deep or small targets, but it also allows the detector to respond to ground signals generated from high-mineralized soils. So, not only are weak signals intensified, so are false signals from iron and other natural magnetic mineralization and electrical interference sources.

While it may be tempting to run at max sensitivity all the time, you don’t drive 100 mph everywhere you go. There are times to decrease sensitivity to improve performance. Toning it down allows you to better differentiate between good targets and false signals from ground minerals. It also filters out the “chatter” from other sources of electromagnetic interference from power lines and the like.

2. Frequency

The frequency gives you an idea of well it will perform for different types of targets and depths. There are single, selectable, and multi-frequency detectors. Single frequency detectors with a high frequency are good for detecting small and even low-conductive objects. Single frequency detectors with a low frequency are good for detecting deeply-buried, large objects. Selectable frequency detectors still operate as a single frequency machine, but it allows the user to select between multiple frequencies to further customize a hunt. Multi-frequency detectors allow for multiple frequencies to be used simultaneously.

3. Ground Balance

Minerals in your hunting terrain like saltwater, black sand, or iron-rich soil in red earth sets off a detector with false signals. This means that these minerals respond to a searchcoil’s electromagnetic field in a similar way that metallic objects do causing the metal detector to provide a signal to the user in a way that they can’t determine if it’s a good object or ground signals. Ground balancing is an adjustable feature and allows for a detector to essentially cancel out these ground minerals and signals, so you can better hear true signals from desired metallic targets.

There are four different types of ground balance:

  • Preset: Factory-set by the manufacturer for average conditions for the average user. Usually, this setting is fine for low-mineralized ground.
  • Automatic: Quick and simple, auto ground balance automatically sets the best parameters for detection in your hunting terrain.
  • Manual: Allows the user the ability to manually set the ground balance. This can be helpful for high-mineralized and tough ground such as saltwater and hot rocks.
  • Tracking: Similar to automatic ground balance, it automatically balances it to current ground conditions. However, it continues to automatically update ground balance if the ground phase and conditions change as you cover more ground.

4. Discrimination (DISC)

This is a detector’s ability to identify a target by ferrous or non-ferrous type and provide this information to the user in various ways. Audio tones and Target ID is the most common way to interpret this data. While the scale range for Target ID varies between models and manufacturers, it’s usually a 2-digit system that displays a probable conductivity value of the target. Lower numbers correspond with ferrous targets like iron and higher numbers correspond with highly-conductive targets like silver.

With discrimination, you can determine if you want to dig a possible good target or pass it up. However, there are some objects that provide a similar Target ID and response signal to good targets. For example, pull-tabs often have a signal response like that of gold. It’s why we say to dig everything in the early days and the shovel is the best discriminator.

Here are common types of discrimination:

  • Iron Reject: Rejects ferrous and trash items so that they do not show up on Target ID and signals are silenced.
  • Variable DISC: Usually in the form of a knob that allows you to increase and decrease discrimination levels. As you increase, the likelihood that small, good targets will be missed and silenced out.
  • Notch Discrimination: This feature allows the user the ability to accept or reject metal types so that the detector only signals you on possible desired objects.

Metal Detecting Techniques

From the best settings to use to how to sweep without swinging, these detection techniques will help keep bad habits at bay and the good ones helping you find more treasure.

1. Use Preset Search Modes

If you’re a beginner and you’re not quite sure how to use advanced and adjustable settings to improve max performance, use the preset search modes. They’re set with the right parameters for detecting a specific type of target or hunting in a specific terrain.

These types of search modes are often termed Coin & Jewelry, Relics or Artifacts, Field, Beach, Park, Gold, and there can be many more depending on manufacturer terms and preset patterns.

2. Customize a Search Profile

Sometimes a preset mode just won’t cut it as manufacturers can’t always predict what the best parameters are for your site. Some detectors will allow you to customize your own program or search mode and save it. Others may allow you to tweak a current search mode to optimize it for your site. As you develop skills and knowledge about how your settings work, you can set the best levels for sensitivity, ground balance, discrimination, and other advanced settings to improve performance and results.

3. How to Sweep Correctly

This may be one of the best skills you can master if you’re going to own and use a metal detector. You’ll often see the terms sweeping and swinging used interchangeably. This is the action of moving the searchcoil side to side while you cover ground to detect targets. Metal detectors are motion detectors, so they must be in motion to detect a target. The idea is to stay slow and low.

  • Overlap your sweeping pattern so that the searchcoil does not miss any ground. The general rule is to overlap your sweep by half the length of the searchcoil. There are patented searchcoils that have an inner and outer coil. The correct method is to use the inner coil as the mark for overlapping your sweep.
  • Move slowly. While a larger searchcoil allows you to cover more ground, you may be tempted to cover it as quickly as you can. Moving too quickly will compromise depth and can cause you to miss weak signals or cut short the duration of a good signal. An average sweep guideline is 2-5 seconds from right to left to right. You can also measure your sweeps as your walk forward in a straight line moving 2-5 feet per second.
  • Don’t tilt or lift the searchcoil at the end of a sweep. This is easy to do as you may naturally tend to swing the searchcoil causing it to lift and compromise depth. Keep the searchcoil parallel to the ground to improve depth detection and response to small objects.
  • Sweep low. Keeping the searchcoil within 1-2” of the ground will provide good depth and coverage. Don’t allow the searchcoil to unnecessarily brush along the ground, bumped, and jolted to prevent excessive wear and tear, random signals, and inaccurate Target IDs.

4. Learn to Pinpoint

Having a handheld pinpointer is extremely convenient and easy to learn, but if you want to learn to do it with your detector, it’ll take practice. A concentric searchcoil is easier to learn with, but a DD searchcoil provides better target separation, depth, and improved performance in mineralized ground. The narrower field of detection in separating adjacent targets is achieved with a DD searchcoil, and therefore, you can better sort through trashy sites for good targets.

To manually pinpoint with a metal detector means making a sweep and marking a line with your shoe or making a mental note of where the signal is the loudest and strongest. Turn 90 degrees from your initial position and make a sweep to mark a line of where the signal is the loudest and strongest. The center of this imaginary “X” should be where the target is located.

5. Look Up Tips

You may need tips about what metal detector you should choose, where and when to hunt, and how you should conduct your research. Being willing to put in every effort into each aspect of metal detecting will be a large part of your success. For some worthwhile advice, check out my long list of metal detecting tips and tricks.

Metal Detector Depth Detection

One of the most asked questions about metal detecting is about depth. How deep can metal detectors detect? Most answers, including my own, often involves the words “It depends…” Frustratingly for the eager beginner, this answer isn’t good enough. Do you want the straightforward truth?  Depth is usually equal to the searchcoil’s diameter for coin-sized objects.

A larger searchcoil will “see” deeper as its field pattern becomes larger. This makes it a great option for detecting deeper for larger objects and covering large ground. Consequently, its field pattern is less concentrated, so smaller targets will be missed. Smaller searchcoils may not have great depth, but its concentrated detection field allows it to detect small and shallow objects easily. It may also improve performance in trashy and mineralized sites.

When I talk about many other factors that affect metal detection depth, these are a few of the obvious factors that you must consider.

Metal Type

High conductive targets are easily picked up by the metal detector, so objects like silver and copper can be detected at much greater depths than low conductive targets like lead.

Target Size, Shape & Orientation

Thin, small, skinny, and long targets are harder to detection at greater depths than wide, circular, and large objects. Its orientation in the ground also plays a role. For example, a coin on its edge as if it were standing up is harder to detect than a coin lying flat in a horizontal position in the ground.

Ground Conditions

Ground minerals can cause a detector to sound off and the chatter makes it difficult to differentiate between good and false signals or to hear weak signals. This may cause you to make setting adjustments that affect depth. But, a general rule to consider is that you can detect deeper objects in low-mineralized ground than you can in high-mineralized ground.

Metal Detection FAQs

Have a question in mind? It might be answered here. Trouble-shooting tips are also answered here. Check it out.

Are Metal Detectors Easy to Use?

Once you learn the ropes, they’re relatively easy to use, but it takes patience, practice, and passion to get there. Metal detecting is often called a hobby and just like any other hobby, the more you practice, the better you get.

In terms of user-friendliness, detectors with automatic features are easier to use for beginners. It takes the difficult performance methods out of the hands of a beginner. High-end detectors usually have additional, advanced settings that requires a lengthy user manual to learn how to use it. These types have a steep learning curve and are geared towards intermediate and expert detectorists that are willing to grow with the detector and maximize its potential.

What are the Best Metal Detectors?

It depends on what type of metal detector is right for you, the target, and the terrain. A diving detector will not serve you when hunting for gold in the desert, and an entry-level coin detector will not endure the challenges of Punalu’u Beach – a black sand beach.  So, the best metal detector is the right one for you that may not be someone’s go-to choice.

Some favorite models to consider by brands with high reputations include:

Why Does Target ID Seem Inaccurate?

If your Target ID is changing with each sweep on the same detected object in the ground, there may be multiple reasons for it that don’t involve the detector being faulty. It could be a large, flat piece of iron, it could be a good target that is lying on its edge, or it could be a good target lying adjacent to multiple trash items. Iron Reject, discrimination, and/or notching features may help to gather more information, but the best way to find out if there is a good target is to dig.

Why Does the Metal Detector Make Erratic Noise?

It could be anything from bumping and jolting the searchcoil one too many times to electromagnetic interference (EMI). Here are a few solutions you can try to remedy it.

  • Check your battery. Replace with a new one or recharge if necessary.
  • Move away from sources of EMI.
  • Ground balance.
  • If you have a Noise Cancel feature, move it to a quieter channel.
  • Reduce sensitivity.

Do You Have to Use Headphones?

Why do professional and serial detectorists use headphones? For a lot of a reasons. They conserve battery life, improves signal volume for even faint signals to be heard, they provide privacy when hunting in public, and they reduce distractions and noise from wind, traffic, crowds, etc.

What are False Signals?

False signals are signals the detector provides that indicates it has detected metal when there is actually no metal present in the ground. This occurs in mineralized soil when particles like iron oxides and salt cause a response in the detector. The usual way to remedy this is to ground balance to cancel out these ground signals.

What it does is the metal detector matches its ground balance to the phase reading of the ground. In highly-concentrated soils, it may reduce some but not all noise, and this is usually acceptable to the user. If not, your only option may be to reduce sensitivity.

Are Metal Detectors Safe to Use with Pacemakers?

Pacemakers are designed to be resistant to electromagnetic field interference, but there is no guarantee that is always the case. So, let’s look to the metal detector.

It has a narrow, concentrated magnetic field that is generated and emitted within inches of the searchcoil, so it would make sense to keep the searchcoil to the ground where it’s supposed to be and not near the pacemaker. Additionally, the magnetic field of a detector is weaker than many other magnetic field sources that we are exposed to, even daily.

Where are the Best Places to Metal Detect?

The best places to metal detect are high-traffic sites where things are lost and can be recovered. Everyone has their own personal opinions on where to hunt depending on the type of target they’re after. If war relics are desired, old battlefields may be the best place to hunt. If jewelry is the goal, the beach is excellent hunting grounds. Some of the most commons sites are:

  • Beach
  • Park
  • Fields
  • Churches
  • Fairgrounds & Showgrounds
  • Streams, Creeks & Washes

For more tips on where to hunt, step on over to my guide with the top 20 metal detecting sites that you must consider.

Metal Detector – Check. Got Gear?

Buying a metal detector is only one component of getting started in the hobby. To use it effectively, you’ll quickly find that you need additional gear to be successful. This means getting the right accessories for the job. Not only are you using a metal detector to detect desirable objects, you’ll need to dig ‘em up, pinpoint, and plug your holes. Is it a sand scoop or quality shovel that you need? What pinpointer should you choose? Using your metal detector means knowing what will compliment your hunting style and how to maximize success.

Don’t forget that choosing the best hunting grounds, knowing the laws and regulations, and doing your research on all things metal detecting is just as important as knowing how to sweep correctly. Hop to it and happy practicing!

Further Reading:

Back to How to Metal Detect Guides