A metal detector is a device that helps its owner find metal objects of different sizes and at different depths. Operation parameters depend on the modification of the device.
Further in the article, we will consider why such a device is needed, its functions, characteristics, as well as models of American Fisher metal detectors.
What are metal detectors?
Depending on what the goal is being pursued, in each particular case, you will need your own modification of the device. The quality of the task will depend on its technical characteristics.
Metal detectors are of the following types:
- deep - they are universal, cover a depth of up to six meters;
- soil - easy to use, but work at a shallow distance from the surface of the earth - these are the Fisher metal detectors;
- pinpointers are specialized professional devices capable of finding the smallest metal objects, up to fragments;
- underwater - sealed devices for scanning water bodies.
Operating principle
The action of the metal detector is comparable to the principle of the radar - it detects fixed objects made of metal at the calculated depth using electromagnetic waves emitted by the search coil. Under the influence of these waves, eddy current flows arise on the surface of a metal object, generating a secondary electromagnetic field that lowers and changes the configuration of the main field of the coil.
Waves are reflected from the surface of objects and fall into the field of analysis of a special microprocessor that processes incoming information.
After that, the technical and physical characteristics of the found thing become known - the composition, shape and depth at which the object is detected. The composition is determined by how the electrical conductivity of the object changes.
The device informs that detection has occurred by light and sound signals.
Applications
Specialized devices for searching for metal objects, including Fisher metal detectors, are not widely used in production, but can be excellent helpers in a highly professional or domestic way.
The metal detector is useful in the following cases:
- more sophisticated professional instruments for working with great depths will be required by archaeologists;
- such a device is useful to search teams to detect metal relics of wars of various historical times;
- if a personal plot needs to be cleaned of foreign objects - the simplest soil model like the Fisher F2 metal detector is useful for this;
- use such devices to search for lost objects on the beaches - vacationers often lose jewelry due to carelessness;
- metal detectors are used in crowded places to search for explosive devices - airports, railway stations, shopping centers.
About Fischer
The American company Fisher with one thousand nine hundred and thirty-first year is a reputable and well-known manufacturer in the field of devices for the search for objects. Its technological devices are used in various fields - from security to searching for treasures.
The company produces families of analog, digital, multi- and single-frequency devices. Among them are both full-fledged metal detectors and portable devices such as the Fisher MScope, the only Fisher folding metal detector in the world. Reviews about it are the most favorable: it instantly folds and moves thanks to the built-in wheels, it is charged from a standard network or batteries. It is used quite widely - in schools, factories, in military operations.
The company's products are also used to search for underground utilities - these are magnetometers, tracers, leak detectors and correlators, level indicators, metal detectors. Devices are used in water and gas facilities.
Soil metal detectors - appointment
In the modern world some time ago, a new type of hobby became widespread - search by instruments. This is an entertaining lesson to discover things hidden in the ground and abandoned buildings. Many dream of finding treasures and treasures in this way. In addition, such a hobby promotes the unification and communication of people connected by one thing, useful stay in the fresh air.
The Earth keeps a lot of mysterious in itself, and the deeper they find a thing, the more expensive it is.
Using underground metal detectors, you can determine the location of modern and ancient coins. And if the former are equal to the denominations, then the latter, with any luck, can cost a lot of money. Often underground find royal silver coins and copper coins.
Search teams in their missions often find military weapons, medals, various historical insignias and other items.
Currently, the Fisher series of ground metal detectors presents devices of the following levels:
- initial - F2;
- semi-professional - early models F4, F5 and top models - F11, F22, F44;
- professional - premium devices F70, F75.
Features of the new F22 model
The device of this series is the second in the line of three presented models of last year.
This device features completely new features:
- the presence of a digital display;
- sound selection of four keys;
- instrument setup programs;
- built-in memory;
- volume control
- partially waterproof.
The Fisher 22 metal detector differs from the third model, the F44, in that it does not have a manual mode for backlight and ground balance, as well as a smaller coil. It has three built-in programs, and one for self-tuning. Powered by two standard AA batteries for twenty five hours.
An interesting feature of this device is that after turning on the device, its serial number is displayed for a few seconds - this is how the manufacturer secured the sign from being erased from the case. In case of theft, it will now be easier to find the device.
After switching on, the metal detector allows the user to adjust the volume and tone of the sound, sensitivity to electromagnetic interference. Custom settings allow you to remove unwanted objects from the field of view.
The device is equipped with a different type of coil - its new shape allows you to explore a larger surface than the old one. At the end of the coil, the pinpoint switch is turned on with a button.
Metal Detector F44
This metal detector has three knees, which are connected by spring buttons, firmly fixed with collet clamps. This design eliminates any backlash. The Fisher 44 metal detector, reviews confirm this fact, are made quite qualitatively, soundly and are now the best choice in their price category.
The device is equipped with a waterproof coil of complex elongated shape, called a drop-shaped, weighing three hundred and fifty grams. The engineers of the company that created this device claim that this form will allow searches in hard-to-reach places - under the roots of trees, among stones or in the corners of the foundations of buildings.
The power of the device is similar to the others in this series, but the headphone jack is located on the side, which is much more convenient than in other models - at the back. The display is well segmented, has several backlight settings and is quite informative.
Premium Metal Detector F75
The Fisher 75 metal detector belongs to the class of professional equipment. Despite this, it is easy to manage and learn. Those who use it note one drawback - a sharp sound. But this is justified by a highly sensitive coil, which allows you to find even small metal objects at a great depth.
Also, users note that this device works great in metal-littered areas and processes signals almost instantly.
In general, it can be noted that the company's products have good technical characteristics and are suitable for both beginners in the search business and professionals in various fields.