How do you choose a robust, repairable metal detector ?

Would you like to know everything you need to know to choose the right detector and go prospecting with peace of mind? Read our guide to buying durable metal detectors, based on feedback from our quality experts. You’ll also find detection products with the LONGTIME® label.

Does prospecting appeal to you? Do you feel the soul of a treasure hunter rising within you? ? Would you like to scan the walls of your country house? Hunting for treasure, meteorites or relics hidden in your garden? Be careful, scanning is a viral hobby!

Whatever the case, becoming a prospector requires you to think about your equipment, and first and foremost: your metal detector. From the beginner's detector, which is versatile and easy to use, to the multi-frequency detector capable of targeting very small objects (a few grams) in heavily mineralised terrain, it's important to understand your needs in order to determine the equipment that's right for you.

Are you ready to take the plunge and want to buy a metal detector that's durable, reliable and repairable, so you can enjoy it for years to come? We're here to help.

Because we think that knowledge is power, we get a little technical. If the rest of this article seems a little complex, simply put your trust in the LONGTIME® label. High-performance metal detectors were recently awarded the label after being independently assessed against our 41 sustainability criteria. And what's more, they're 100% French.

How does a metal detector work?

So as not to mislead you, we would like to point out that this article excludes radiation detection devices and deals only with metal detectors intended for prospecting, not for security (airport) or DIY use.

Metal detectors, long ago known as "frying pans", can be used for a wide variety of purposes. Here's a small selection of the possibilities:

  • Search for gold nuggets, precious metals, non-ferrous metals (precious alloys), wedding rings, lost jewelry or coins (silver).
  • Search for hidden family treasures, meteorites or simply your lost keys!
  • Search for farm implements, locate pipes or networks

There are many other uses, and metal detectors can even be used in highly specialised fields such as archaeology, mine clearance or medicine. But what exactly is a metal detector?

All metal detectors operate on the same physical principle: electromagnetic induction.

Recreational metal detector discs are equipped with a transmitting coil and a receiving coil. The magnetic field produced by the transmitting coil will be disturbed and the receiving coil will perceive the signal shift caused by the buried metal object. Once analyzed and translated, this disturbance will generate a sound signal to alert the prospector and enable him to locate the metal object.

The detector reacts, transmitting the information to the control box and sounding the alarm. But as each target has its own conductivity, it remains to be seen whether it's a beer cap, a hunting cartridge left behind by hunters, an aluminium pellet or the ring you've lost. As not all metals are of interest, the detector's performance and ability to detect accurately will come into play in order to discriminate between metal objects of no importance to you, such as small iron objects or large ferrous masses.

Lastly, like a mini ground radar, and depending on the nature of the target, its depth and its shape, the detector will produce sounds with different tones, enabling prospectors to target the area and choose whether to get out their mini-excavator to dig or to move on. Obviously, many other parameters influence your decision.

Metal detectors can be either battery-powered or battery-powered. The objective remains the same: to supply the electrical current needed by the disc and its coils to produce the magnetic field, but also to supply the energy needed by the electronics to translate the signal and convert it into sound.

How to check the reliability and robustness of a metal detector?

You've been eyeing a metal detector, but are you sure of its quality?
To ensure you make a safe and reliable purchase, there are certain features and points we recommend you pay attention to: deciphering.

  • The reliability of metal detector circuit boards:

Every detector contains a whole range of electronic components, from the simple potentiometer to the loudspeaker and the adjustment controls... This is an essential part of your detector. There are two types of electronic board: the electronic board in the disc and the electronic board in the control box.

These cards are the brains of your detector. They are responsible for processing changes in the signals received by your disc and converting them into sound (beep). The on-board electronics also let you change the detection frequency (khz) and save your favourite setting;

"The choice of components made by the manufacturer, the quality of the board's design and architecture, and the way they are assembled are crucial points."

On this point, the company's know-how is essential, and as is often the case with high-tech products, the quality of the electronics is crucial to the life of your detector.

Also bear in mind that the best electronic board in the world, equipped with the most reliable components but running with poorly developed internal software, will not give you satisfaction. Choose experienced manufacturers who design 100% of their own boards and associated software, to ensure complete control of their products.

Be absolutely sure to check the company's policy on electronics: how long boards are available, the possibility of repairing components, reconditioned electronic boards - don't be afraid to ask questions!

  • Robust and reliable detection discs :

Your detector's disc is essentially made up of copper coils. The quality of the coils, the way they are integrated into the disc and the way they are immobilised will make a real difference to the performance and lifespan of your disc.

Once again, the know-how of the major brands will be a good indicator.

Two other points should be considered when assessing disc quality:

  • plastic quality
  • the quality of the resin. If you can get your hands on the disc, check the quality of the resin. Hard resin discs will last longer than soft resin discs that are prone to breaking or cracking. In all cases, the use of a disc protector is essential to protect this sensitive area.
  • The quality of the mechanism linking the disc to the rod. Most of the time, the discs are connected to the rod by a fork and a clamping pin. This plastic fork must be able to withstand the repeated micro-shocks induced by practice;

Something to bear in mind when making your choice: out of 100 prospectors, the majority of failures (60%) concern the wire of wired disks, a highly critical failure.

  • Quality and reliability of detector rods :

Detector rods must be robust yet lightweight. There are two types of rod on detectors:

  • traditional canes
  • telescopic canes (adjustable and foldable)

In both cases, we recommend that you choose rods made from stainless materials. Rods will be subjected to numerous micro-scratches and micro-impacts (brambles, earth, branches), so it's important that the rod is made from an alloy that is resistant to the various forms of oxidation.

If your rod is not made from stainless materials, make sure it has a really robust coating or paint that can withstand the conditions of use imposed on detectors.

Don't hesitate to check the quality of the plastics too, especially the armrests. Ideally, they should combine comfort and durability (resistance to UV rays, sun cream, impact, etc.). Some brands use virtually unbreakable plastics.

Finally, remember to check the quality of the adjustment and tightening elements (rod height, disc inclination). Although they are not exposed to heavy stress, it is important for your comfort that they are well designed.

  • Durability and robustness of the detector control box :

Control units are put to the test: wind, rain, humidity, dust... everything electronics love.

So choose well-designed cases, with well-thought-out sealing and sturdy plastics.

Also bear in mind that in sensing practice, the use of control buttons will offer greater reliability than switches, triggers or potentiometers.

  • Detector battery life:

More and more detectors are battery-powered, to the detriment of rechargeable batteries. Lithium batteries are a guarantee of peace of mind and performance. However, not all lithium batteries are created equal. Finally, don't forget that batteries have a limited lifespan, so find out before you buy about the availability of batteries and the method and cost of replacing them.

NB: For all the components of your detector, the choice of quality materials and the company's design and integration expertise will have a major influence on the lifespan of your product and its ease of use. So beware of low-cost metal detectors, which may still represent an investment but which will give you absolutely no satisfaction.

Which metal detector is right for you?

From metal detectors for children or beginners to high-end detectors for demanding users; from gold and beach metal detectors to underwater detectors; what are the best metal detectors for a good start? ?

There are many comparators on the web, and you will quickly notice the lack of independence of their links. To try to help you make an objective decision and determine the search device that will enable you to detect effectively and make good finds, it is advisable to look at several points of determination. Here are some of the factors that should influence your choice.

  • Typology of the detection site :

Thinking about where you are going to detect most of the time will help you choose a detector or disc adapted to your practice:

    • On the beach, choose a detector that is highly resistant to sand and corrosion. Ideally, it should be waterproof in case it comes into contact with water;
    • In the forest, opt for a compact detector that is both easy to handle and robust. You'll also need a disc that can be lowered in frequency to gain a few centimetres (cm) in depth.
    • In the field, choose a lightweight detector that can withstand dust and mud.
  • Your budget :

As with everything, budget is always a determining factor in choosing your detector, but beware of false good ideas. Under €150, there's a good chance you'll end up with a disposable detector, closer to a child's toy than a real detector. Choose retailers who specialise in this field, and don't hesitate to ask other enthusiasts for advice, to visit a specialist forum or to ask professional retailers for advice.

Entry-level detectors (€150 to €200) :

They are generally very limited in terms of performance and comfort. With random detection accuracy, less power and fewer settings available, they may give you a taste of the pleasures of detection, but they are unlikely to offer you an optimal experience. What's more, the detectors are subject to a lot of stress and are put to the test during outings, so beware of the risk of breakdowns and breakages. In this price range, we'd still recommend you look at the big brands or buy refurbished or second-hand products.

Mid-range detectors (€200 to €500):

These detectors will allow you to get started properly and enjoy your work thanks to enhanced comfort and performance. The different search modes give you access to finer settings, higher power and a more polished finish. In this range, it's possible to find detectors with a telescopic pole and lithium battery for a more enjoyable experience.

Top-of-the-range detectors (€500 to €900):

Accuracy, comfort, power and reliability: welcome to the world of demanding prospectors. Detectors in this price range offer excellent performance and high sensitivity, capable of detecting targets at great depths. They are generally lightweight, with a wide range of options and settings for a higher detection range.

These detectors also offer excellent versatility, with the advantage of being usable on all types of terrain and for all types of targets, offering different detection modes, from low frequency to high frequency.

Although the set-up of these devices is a little less intuitive, they are perfectly suitable for beginners and will retain a strong value on the second-hand market.

Wired and wireless metal detectors:

In the category of detection devices, two technologies are present on the market: wired and wireless detectors.

When it comes to reliability and lightness, wireless sensors are the winners, offering without doubt the best value for money in terms of longevity.

In fact, the most serious failure of a detector comes from a break in the connection between the wire and the detection disc. Wireless detectors are a ground-breaking innovation in terms of reliability, completely eliminating this risk of critical failure.

What's more, wireless detectors enable interoperability between the cane and other disc shapes and sizes (elliptical, large diameter), and transmit the detection signal to other accessories (remote control with LCD screen, wired or wireless headphones, etc.) synonymous with lightness, comfort and maneuverability.

Comfort, space, maneuverability:

Metal detectors can offer different levels of comfort, ergonomics and manoeuvrability. If you're more of a trapper and like to go detecting in remote areas, choose metal detectors with wireless discs and a telescopic pole. You'll be able to store your detection equipment (pin pointer, holster, water bottle, brush) in a small rucksack, and if you also opt for a small folding shovel, you'll be perfectly mobile.

"N.B.: In all cases, as with any portable device, bear in mind that the weight of the detector is an important factor in your comfort. A detection outing can last several hours. To avoid musculotendinous disorders, choose detection equipment that's really light, ergonomic and correctly adjusted."

How to make your metal detector last as long as possible:

Our watchword is "Read the use and maintenance instructions" for your detector. As well as learning the right reflexes to maximise the life of your device, you'll find it easier to get to grips with and use it. you'll learn how to set it up properly.

To avoid breakdowns and problems with your metal detector, there are a few basic rules to follow:

  • Choose a detector adapted to your practice (frequency of outings, detection location)
  • Follow the manufacturer's instructions for use and care.
  • Use suitable covers to protect parts exposed to rain or dust if they are not designed for it. Moisture is particularly dangerous for the batteries and electronics in the case.
  • Be careful when carrying your detector (use a carry bag) and avoid wearing it on your belt.
  • Always protect your disk with a disk protector.
  • After each use, clean your detector with a damp cloth.
  • Remove the batteries from your detector when it is not in use.
  • Perform charge/discharge cycles on your batteries.

If you apply these few basic rules and have chosen a durable detector, i.e. one that is robust, reliable and repairable, you should be relatively safe. However, no brand is immune to failure, and no product is infallible.

If we're talking about extending the life of your device, we need to distinguish between two types of detectors: wired and wireless.

Maintaining a wired metal detector and extending its service life :

The main point of attention on this type of detector concerns the junction between the detector disc and its cable. As a general rule, cables do not unscrew and are soldered directly to the reel. The splice must be carefully monitored and protected from shocks and tensile forces. The slightest alteration could mean the end of your detector's life; be vigilant and careful. Wrap the detector cable carefully around the cane and avoid hipmounting.

Maintaining a cordless metal detector and extending its service life :

Unlike wired detectors, wireless detectors are less exposed to the risk of breakage or critical failure. However, remember to protect your disc each time you go out with a suitable disk protector, and to clean it when you return.

Also periodically check the connection between the disc and the rod. Tightening must be nominal, neither too tight nor too loose.

Wireless disks are logically equipped with an internal battery. Beware of deep discharge by performing a monthly charge/discharge cycle and avoid storing your drive in an overheated or very cold place.

Protecting the detector disc :

Whether your detector is wired or wireless, it is highly likely that the lower part of the disc, the part facing the ground, is made of resin. This resin is injected to immobilise the coils completely and permanently. The quality of resin varies, but in all cases the use of a disk protector is highly recommended to preserve the integrity of this resin and therefore of your disc.

Protecting the detector rod:

If your rod is telescopic, periodically clean all the clamping and adjustment elements (remove dirt, dust and dry). If your rod is not made of stainless steel, check the integrity of the paint to avoid any risk of corrosion.

The detector control box :

Don't hesitate to use protection if your case is insufficiently protected.

Control boxes must be protected from moisture and dust.

If your control unit has an LCD screen that is not protected (as is the case with smartphone screens), check the accessories section for protection systems.

Overall, clean your detector regularly to minimise the risk of failure. It's just a question of common sense, but it will help preserve the integrity of the paintwork, the electronics and all the fasteners.

How to repair your metal detector?

In the event of a breakdown, check the warranties first:

  • If your detector is less than two years old, contact the distributor who sold it to you. He is legally responsible for the 24-month legal guarantee of conformity, excluding consumables.
  • If your detector is more than two years old, check whether you have taken out additional insurance or extended warranty cover. You should also check the manufacturers' warranties, as these may be extended to take over from the legal guarantee of conformity;

Your product is no longer under warranty, don't panic!

Well-made metal detectors are products that can be repaired in the event of a breakdown:

  • In all cases, first contact the after-sales service of your product brand, either directly with the manufacturer or through your dealer.
  • Before undertaking any repairs, always check that the problem is not with the battery or the rechargeable batteries. Also check that the charger for your appliance is working.
  • Don't forget to check your settings too, as you may have unwittingly completely over-set your device or switched to detection modes that are completely unsuitable. Refer to the user manual to understand the problem.
  • Beware of ground effects, electromagnetic interference and objects with high inductance (buried networks, groundwater, underground, high-voltage lines). They can be a source of interference and cause unpleasant sound signals.

Detector disk failures :

On the disc side, there is not much scope for repair. Detection is extremely hard on sensor discs (dust, shock, mud, humidity) and to meet these constraints manufacturers have to seal the coils and on-board electronics very precisely.

  • If you have eliminated the above causes and your drive really does seem to be malfunctioning, contact your distributor or the manufacturer's after-sales service to check what can be done.
  • If your detector is wired and your wire has broken or deteriorated, it's unlikely that it can be repaired, but check anyway.
  • If your detector is wireless and the problem is with the disk battery, check the conditions for replacing the battery.
  • If you've broken your disc and it's no longer watertight, you've got to stop trying to hammer nails into it!

Detector control box failures :

Your control box will be particularly exposed to moisture and dust.

If it has an LCD screen or display, it may also be subject to accidental breakage.

  • If you have broken the lcd screen on your case, check with your dealer/manufacturer to find out how to replace it.
  • If the battery fails, check the conditions for replacement. There's no reason why it shouldn't be.
  • If the connection between the wire of your wired detector and your control box is faulty, it can be repaired as long as there is a sufficient length of wire available.

Detector rod or arm support failures :

At the bottom of the rod, there is a joint with the disc. Although robust, this joint is not unbreakable, so be vigilant about its condition and be flexible in your movements when detecting near rocks or in the forest, for example.
Be doubly, even triply, vigilant if the disc is welded to the case! (yes, there is such a thing).

  • If you've broken your arm support, don't worry, it can be easily replaced.
  • If you've broken your rod by accident (grizzly encounter, trunk closure), you should be able to replace it easily.

Detectors and DIY

For the more do-it-yourselfers among you, some problems can be solved by DIY (self-repair). The Internet is full of explanatory videos, and there are many groups on forums. You can learn how to replace a battery, change an LCD screen or clean your equipment properly. However, as with all electrical or electronic products, and particularly high-tech appliances, make sure you have a solid grounding so that you can work safely and not do worse than better.

When it comes to durability, it's essential to make sure that your detector's manufacturer has a high-quality after-sales service. All LONGTIME®-labeled products are repairable, so don't throw them away.

In summary, to choose a durable metal detector :

  • Choose brands with genuine technical support and a training plan for distributors.
  • Check not only the availability of spare parts, but also their price.
  • If your detector is wireless, make sure that the battery is replaceable, and that the technical and financial conditions for replacement are economically viable.
  • Make sure the various priority parts are accessible: control box battery, electronic board (apart from the disc), lcd screen...
  • Ask about the quality of the rod, the armrest, the disc and its coils, and all the electronics.
  • Try out the detector you've been eyeing.

Would you like to buy a reliable, robust and repairable metal detector without a degree in electronic engineering and without poring over 15 comparisons and 10 blogs?

Take a look at our product directory and you're sure to find what you're looking for!

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