Comparison Minelab E-Trac Standard vs Minelab CTX 3030

- Ground. Metal detectors designed to find metal objects buried in the ground - from coins and other historical artifacts to pipelines and caches. They can have different characteristics and scope of application - from the simplest models, suitable only for collecting scrap metal, to powerful professional devices capable of searching even at a depth of a couple of meters. The coil can be protected from moisture (see below), but ground metal detectors are not designed for complete immersion in water.

- Underwater. Metal detectors, designed, as the name suggests, to search for objects under water - primarily at the bottom of reservoirs. Their main features are due to optimization for the environment: a sealed waterproof case (in most cases, with the ability to submerge the entire body to a depth of several meters), the ability to work with wet salty soils, and a weight distribution designed for ease of use under water. Also, such models are usually equipped with waterproof headphones. Note that buying such a device for land use is hardly justified: holding an underwater metal detector in the air is not as convenient as a regular ground detector, and the expensive moisture protection of the case loses all its meaning.

- Inspector. Devices designed to conduct searches and search for metal objects on the human body, under clothing. They are used by law enfo...rcement agencies, security services at airports, train stations, security agencies, etc. Note that in this case we are not talking about stationary “frames”, but only about hand-held detectors. Almost all of them belong to pinpointers (see “Type”) and have a fairly compact size. Thanks to this, the device can be used as a portable device for express inspections, constantly carried with you along with other equipment. However, such a detector can also be useful at a stationary checkpoint, in addition to the frame - it helps to determine exactly where on the body the object that “disturbed” the frame is located.

— For mine clearance. Highly specialized metal detectors for detecting mines or other explosive objects left by the echo of wars and hostilities. Such devices do not need to separate finds by type of metal. Their main purpose is to search for large projectiles, but there are other types of devices for solving specific problems (for example, detecting plastid with a fuse). Small pieces of hardware are usually ignored by such metal detectors. Mine clearance detectors are rarely found in common use, and they are incredibly expensive. Devices for this purpose are heavy and inconvenient, but durable and resistant to weather conditions. They are aimed at professional use by the military and rescue workers.

The greatest depth at which a metal detector is guaranteed to be able to detect a metal object. Note that this parameter is most often quite approximate, moreover, somewhat conditional. This is due to the fact that it is usually indicated for an perfect environment (low-mineralized soil, a fairly large object, the material of which optimally matches the frequency of detection of the coil, etc.), and even for such conditions it is difficult to derive an absolutely accurate value. Therefore, in fact, the detection depth is highly dependent on a number of additional factors (from soil characteristics to user skills) and can be significantly less than indicated in the characteristics. Nevertheless, the claimed depth describes the capabilities of the metal detector quite well, and it is quite possible to compare different models with each other.

Note that a large depth not only increases the cost of the device, but can also adversely affect its ability to detect small objects.

The deepest depth at which a metal detector is capable of detecting small coins and other objects of similar size. Many users buy a device with the intention of “hunting” for metal trifles, so manufacturers often indicate this parameter separately in the specifications. Due to the small size of the coins, their detection depth is usually much less than the total maximum detection depth (see above).

The number of pre-installed programs for searching for various materials. Their number reflects the capabilities of a particular model, allowing you to start working right off the bat.

Regular metal detector search programs include detection of coins, all metals, jewelry and relics. In some models, this list can be expanded with "Beach" programs, custom (user) detection mode, etc.

— LCD display. The presence of its own display in the design of metal detectors. This feature makes working with the device more convenient and visual: through the display, you can display more different information than with the help of an audible alarm or indicator lights, and it is easier to perceive. On the other hand, such devices are more expensive than similar models without a screen.

— Arrow indicator. The presence in the design of the metal detector of an analogue dial indicator to display data on the search process. Such an implementation is much more modest and cheaper than the same LCD display, but an order of magnitude more convenient than without visual notification at all.

— Display backlight. The presence of a backlight allows you to use the display of the metal detector in low light conditions — up to complete darkness. Note that this function can be useful not only at dusk, but also in the daytime — for example, when searching in a dense forest in cloudy weather. See above for details on the display.

— Built-in speaker. The presence in the design of the metal detector of its own speaker. Such a speaker allows you to use the device without headphones, which are not always convenient, and sometimes unsafe (for example, when working in places where traffic can move).

— GPS module. The pre...sence of a GPS satellite navigation module in the design of the metal detector. This module allows you to determine the current geographic coordinates of the device, and the options for using this data can be different: recording search routes, fixing the places of individual finds, and even full-fledged navigation with laying routes from point to point.

— Armrest. The presence in the design of the metal detector of an additional support in the area of the operator's elbow. This support reduces the load on the hand, and also makes the hold more stable and at the same time controllable, allowing you to comfortably hold the device in one hand.

— Headphone output. The presence of a headphone output in the design of the metal detector. This can be either a standard connector that allows you to connect any compatible "ears" (for example, a 3.5 mm mini-jack output, popular in portable audio equipment), or an original proprietary interface that allows you to use only specialized "native" accessories. Anyway, headphones are often more convenient than a speaker, as they allow you to hear the signals from the device well even in a rather noisy environment.

— Headphones. The presence of headphones in the scope of delivery of the metal detector. Usually, such headphones have high quality and accuracy of sound transmission, so that the user can be guaranteed to hear all the signals and tone shades of the signals. "Ears" can be wired and wireless, and in underwater models (see "Type"), they are, respectively, made waterproof. This function is convenient because you do not have to search and purchase the best headphones for the metal detector on your own.

— AA. Replaceable elements, known colloquially as "finger" type. They can be both in the form of disposable batteries and in the form of rechargeable batteries. They are produced by many manufacturers, and different brands differ in price and quality, which gives many opportunities to choose the optimal option. And AA batteries are sold almost everywhere. On the other hand, they are usually required in large quantities — about 8, because metal detectors consume quite a lot of energy; and the elements themselves are most often not included in the set.

— PP3. Replaceable batteries of standard size, in a characteristic rectangular case with a pair of contacts at the end, nominal voltage of 9 V. They are more powerful than the popular AA elements, but they are noticeably less common. They can also be produced in the form of rechargeable batteries.

— Proprietary battery. Tools powered by its own battery (often built-in), which does not correspond to the standard sizes of replaceable elements. Such batteries can have a high capacity and power and are often more convenient than replaceable elements. In addition, they are usually supplied with the device, which eliminates the need to look for power supply yourself. The main disadvantage of this option is the impossibility of quick replacement in case of exhaustion of the charge — the battery will have to be cha...rged, and this requires not only a power source, but also time. Theoretically, if the battery is removable, you can keep a spare charged battery ready, but in practice, spare elements are expensive, and it may be difficult to find them. For a number of technical reasons, such type of rower supply is rare, it can be found mainly in high-end models.

— 18650. The name of these batteries comes from their dimensions: 18.6 x 65.2 mm, cylindrical in shape, they look like slightly enlarged AA, but have an operating voltage of about 3.7 V and a higher capacity. In addition, all elements of the 18650 type by definition are not disposable, but rechargeable batteries (lithium-ion type).

— C. Replaceable elements of standard size, cylindrical shape, with a nominal voltage of 1.5 V. In length, they practically do not differ from the AA described above, but they are much thicker, due to that they have a higher capacity. At the same time, this type of power supply is quite rare; this can be said about the batteries themselves as well.

The longest possible time of continuous operation of the metal detector without changing or recharging the batteries. Usually, some “perfect” time is indicated for the most optimal mode: constant stable operation of the coil without unnecessary energy consumption for sound signals, display indications and other additional functions, fully charged batteries or high-quality replaceable batteries, etc. Therefore, the actual time of continuous operation is likely to be somewhat less (how much depends on the features of the work). Nevertheless, this parameter describes well the battery life of the metal detector and allows you to evaluate its suitability for work "in isolation from civilization" (as well as the estimated number of spare batteries that may be needed for a complete survey of the desired territory).

Additional accessories and parts included with the metal detector. These can be devices for protection and ease of carrying in the working position or during transportation — belts, bags, cases, rain covers for the control unit; special equipment required for work — for example, a grounding rod for models with the RF operating principle; and other additional equipment. The presence of batteries and a charger for them in this paragraph is indicated only if the device uses replaceable elements (see "Power"), because cordless metal detectors are by default equipped with a battery and “charging”, and there is no need to specify this. Also, this paragraph does not cover spare replacement coils — their presence or absence characterizes the “Number of coils” paragraph.