For the vast majority of finding treasure and Amateur archaeology is a hobby: expensive, but fun, like fishing, hunting and other types of active rest. In most cases you have to enjoy the result, and the process in the fresh air. But sometimes the result, if you search well to prepare.
Conventionally, all the detectors can be divided into three large categories (first turn consumer properties, and not just the methods of forming, signal processing and presenting information):
- devices of initial level;
- devices intermediate level;
- semi - professional and professional devices.
In turn, the detectors according to the principle of processing and displaying information divided into 2 categories:
- digital;
- analog.
Semi - and professional instruments mainly digital, with powerful algorithms signal processing.
Typically, devices of the middle level are simplified versions of professional devices and are more adapted for the novice user.
Analog devices built without the use of powerful processors and signal display contain 1-3 (more "advanced" models 5-6) regulators, responsible, e.g. for the volume setting of the audio signals, sensitivity, discrimination, etc.
Digital devices, along with a powerful processor and changeable depending on conditions programs search (as well as the ability to create their own programs with a lot of customization) contain a display that may be displayed:
- the spectrum of the signal and/or a kind of "average" information about the object;
- the depth of the object;
- the size of the object.
In addition, digital devices have many tunable parameters affecting (and not) on the depth and comfort of searching.
What device (analog or digital) to choose the novice user, depends from his personal preferences. If there is no desire to understand deeply numerous settings and immediately turn and look - it is better to buy digital entry-level instrument. If satisfied performed manually the corresponding potentiometers settings - you can select analog the metal detector.
The difference of the properties of expensive and cheap metal detectors
The difference between cheap and expensive models lies only in the methods of radiation radio waves and the methods of catching, processing and interpretation of secondary signals.
A more expensive device can:
- to determine with some degree of probability of appearance of the detected metal to it extract;
- to determine the depth of the findings;
- to build up minerals from the soil;
- use many different extra features that increase the performance and efficiency of search, which are absent from cheap devices.
Capacity and good features of metal detectors
Good metal detectors can have lots of different skills:
- firstly, can produce discrimination (discernment) targets it allows you to ignore various types of garbage that are not of interest;
- secondly, able to eliminate the earth's influence on the search process.
This is partly solved by using "Fradiavolo" screen around the coils, and the best is the screen made of iron oxide. At independent the design of the detectors screen is made, usually of tinned a thin copper foil.
For better suppression of the influence of land use special circuit solutions. This method in foreign literature has received the name SEV (Ground Exclusion Balance) - elimination of the influence of the earth.
It should be noted that the presence of metal detectors systems GEB, it's not always possible effectively rebuilt from the influence of the soil. Fortunately, most of the site our country's "heavy" soils are rare.
To the "heavy" soils include: raw sea sand, red oxide, rocky soils, etc.
What you need to know when choosing a detector for depth detection
Coin diameter 25 mm (snout USSR) is detected from 10 cm for the simplest devices up to 50 cm for very serious. Depth of detection is highly dependent on the size of the sensor (typically the diameter of the disc with coils). Roughly, for such coin detection depth approximately equal to the diameter of the search coil.
The smaller coin will be detected at smaller distances. For example, depth of detection of the coin 1 penny will be approximately two times less than indicated above for Nickel.
Helmet, an axe, a small nucleus, the gun can be detected up to a depth of 1 m. In this case, the detection depth depends weakly on the size and type of the sensor. It may be coplanar coils, and orthogonal to the rod. For sensor with larger diameter coils and sensor system with orthogonal coils on the rod depth discovery will be just 20% more in the transition from the disk sensor with a diameter of 20 cm to the sensor-diameter 30 cm Metal shield, bell, large Cannonball.
Depth of detection also depends weakly on the size and the type of sensor and is 1.5-2.5 m for models of detectors of different levels.
There is a theoretical limit beyond which the electronic metal detector does not able to register objects in principle, despite arbitrarily large their sizes. Because the amplitude of the reflected signal is inversely proportional to 6-7th degree distance, and the size of the object depends only 3-5 degrees.
The value of the theoretical maximum depth of detection is 1 m for the simplest of devices with disk sensor up to 4 m for complex devices with the large sensor of orthogonal coils on the rod. Unfortunately, it is this the value commonly adopted for advertising purposes, but at this depth you will not find nothing!
The most modern electronic metal detector can detect a medium coin at the depth of maximum 50 cm, and large massive metal object a maximum of 2.5 m.
In search of 90 % luck and preliminary training, and only 10 % determines the quality of the detector.
Main group metal detectors (metal detectors), searchable coins, treasures, relics
The characteristics of the detectors (metal detectors), which are suitable for finding coins, treasures, relics, can be divided into several groups. Consider them according to the principle "From simple to complex".
Group 1. The simple ground metal detectors
Price level from $80 to $300.
Features. Designed for beginners, have a small set of functions in search.
The principles of operation. To locate the target using one or two frequencies, include discrimination, at least - the definition of depth.
Detection depth (depending on soil type!):
- small coins "flakes" (coins ages 15-17) 3-5 cm;
- major coins, for example, of a Nickel reign of Catherine the Second - 15-20 cm;
- helmet, ax - 20-30 cm;
- cover of the hatch - 70 cm.
Group 2. Semi-professional metal detectors
Price level from $400 to $700.
Features. Designed for people who have sufficient experience in search, have quite a wide range of functions in the search.
The principles of operation. For detection purposes, provided the use multi-frequency radiation, are able to operate not only sound, but and visual information, i.e. visual information is displayed on the display, where you can see VDI detected object:
- if VDI in the positive zone (is a plus), it means that the metal detector has detected the non-ferrous metal, and the value of VDI can to determine with accuracy up to 70%, what color object is detected;
- if VDI in the negative zone (value is "negative"), it means that the metal detector has detected a "black" metal.
Copper and silver coins always produce a value VDI close to maximum values. On different digital detectors minimum and maximum value VDI is different, for example, -10 to + 700 or -30 to +50. That's why these the devices can be classified as semi-professional.
Detection depth (depending on soil type!):
- small coins "flakes" (coins ages 15-17) - 5-15 cm;
- major coins, for example, of a Nickel reign of Catherine the Second - 25-30 cm;
- helmet, ax - 40-50 cm;
- cover of the hatch - see 100-150
Group 3. Professional underground metal detectors
Price level - $700.
Features. Designed for experienced searchers have polyphonic discrimination, multi-scale search, a lot of manual and automatic settings, i.e. a very wide range of functions in search:
- you can detect "color", "black" up to 80 %, which enables more accurate search field, where a lot of household of iron;
- when signal is detected using visual, digital, and audio the alarm.
Analysis of these readings and allows you to define:
- what is found;
- what is the depth;
- what is the size of the detected object.
The principles of operation. This is the computer to search, which entirely use digital signal processing microprocessor. It provides search and highlight all the "color" of objects the sample surface.
Detection depth (depending on soil type!):
- small coins "flakes" (coins ages 15-17) - 15-25 cm;
- major coins, for example, of a Nickel reign of Catherine the Second - 30-45 cm;
- helmet, ax - 50-80 cm;
- cover of the hatch-150-200 cm.
Group 4. Metal detectors for finding gold nuggets
Price level - from $800.
Features. Designed for experienced searchers have polyphonic discrimination, multi-scale search, a lot of manual and automatic settings Almost the entire range of such detectors can be classified as professional. They have a frequency to detect even the slightest of contents gold in any environment.
Gold has a fairly typical VDI, but very similar to the foil (as in audible and visual discrimination). Trim the foil from gold or to find the Golden grain in the ground very difficult.
Metal detectors for finding gold are designed so that they emit the frequency of gold more than the frequency of all other non-ferrous targets. When indicators to search for other "color" goals remain high.
Group 5. Underwater metal detectors
Price level - from $800.
Features. Designed for experienced searchers have polyphonic discrimination, multi-scale search, a lot of manual and automatic settings. They have a sealed body, headphones. Visually they do not give out information, only audio.
The principles of operation. The settings in these detectors are designed to take into account not only salinity, but also interference caused by water in fresh and in salt water interference different.
Area of use. Search at the bottom of the pond, on the beaches, in the coastal zone.
Depth of detection depends entirely on search.
Group 6. Deep metal detectors
Price level - $700.
Features. Calculated only on the detection of three-dimensional objects located on the depth and can't find a coin, which lies at a depth of several centimeters from the surface.
Features of work. Virtually no discrimination, i.e. upon detection subject, it is necessary to dig him up to see what was found. Such metal detectors are usually used during excavations on the battlefields of WWII, where subjects can be covered with soil more than 1.5-2 meters.
Detection depth (depending on soil type!):
- individual coins at a small depth - does not detect;
- a hoard of coins of 1.5-2.5 m;
- large metallic objects - 3,5-5,5 m.
Deep coil. Firm created by Garrett universal detector GTI 2500 deep special coil. It is much inferior in size the coils of deep-detectors, but gives the opportunity to use one the detector for various types of searches.
Group 7. Pinpointer (metal detectors precise definition of the subject)
Prices from $400.
The name comes from the English words Pin Pointer (point index).
Features of work. A detector for detection accurate to the millimetre, location of the subject. Such detectors have discrimination and serve to detect inside the walls. Some search engines use for detection small coins in the excavation.
The main purpose of pinpointer - specify the exact location metal object at a shallow depth of search (up to 5 cm).
The main issues when choosing a metal detector
First of all you must decide on several key issues before choice of detector:
- what you want to look for;
- in what environment are you planning to organize a search;
- do you need the definition of an indicator that supposedly fixed the device (i.e. you need a metal detector or metal detector).
How to choose a metal detector for a specific task
Buying kladoiskatelskoe device for the first time, try to avoid as too cheap models and expensive professional devices. Cheap, poorly sensitive device, may not meet your expectations and unreasonably to disappoint in the treasure hunt and a detector. Likely that for the first time faced with expensive computerized device, you will be hard to master it quickly and effectively.
Case 1. Need to find a specific treasure
The probability that this treasure will be detected, is 5-10 %. The following statistics and interesting examples leads the website http://klad.kiev.ua/. Well worth a visit.
- First, before you start searching it is necessary to study the literature to find detailed maps, meet the local guide.
- Secondly, it is necessary to determine, at least to a first approximation, what this treasure is, its size, how it is Packed.
- Thirdly, it is very important to estimate the approximate depth of the alleged treasure.
- Fourthly, it is useful to consult with colleagues in various forums in The Internet.
- Fifth, decide whether to buy a metal detector, or you can attract someone who already have the device.
If you still decided to buy a metal detector, it should be strictly choose based on the above tasks. Without these prior events to choose a metal detector based on the story sellers and dealers is pointless waste of money.
If preliminary estimates suggest that the treasure is located at a depth greater than 1.5-2 m little what metal detector will help. The maximum depth, which is really something to find up to 2 m, and only if there is a huge object. Believe me, no one in their right mind in great depth not digging.
To buy serious and expensive metal detector in this case is not necessary. Too small the probability that something will be found and you will be refunded the money spent.
Perhaps an inexpensive entry level metal detector that get acquainted with the possibilities of modern metal detectors. Anyway received epinephrine and healthy cheerfulness og regular outings outweigh light grief, financial expenses and will prevent problems with health from a sedentary lifestyle.
Case 2. Are you interested in archaeology, ancient coins
In this case, pay special attention to the quality of discrimination of objects and the sensitivity of the detector. Buy a metal detector with a large search coil. Best of all - if you have two coils 21 and 28 cm. It is very desirable to buy a computerized metal detector with good service.
Case 3. The aim is to look for lost gold jewelry on the beach in Crimea
As in the previous example, notice the discrimination. On the beach is better to work with coils with a diameter of 21 cm you Can choose the cheaper the metal detector, but definitely computerized, otherwise you risk to clean the beach from aluminum beverage tubes (the ratio of caps and findings Golden things on average 400 to 1!).
Pay special attention to the waterproof search coil and the whole device in General.
The metrics that can evaluate the purchased device
There are important technical indicators and opportunities that are desirable to consider when buying a metal detector (metal detector):
- the presence of sectoral modes of discrimination, with clear indication;
- the depth indicator of target detection;
- several modes of the detuning from the influence of the soil;
- the size of the search coil;
- unit weight not exceeding 2 kg;
- continuous operation time with one set of batteries for more than 10 hours;
- waterproof search coil;
- the ergonomics of the stem.
For some search engines, making short outings, weight, ergonomics detector and the batteries will not be the main criterion when choosing a device.
Whereas for others, prowling through the fields all day, which is very important indicators. If you're going to look at the beach, you should pay attention to waterproof coil.
Calculations of the ratio of capability and price when choosing your first metal detector
Consider prices on several budget of detectors, for example, from the firm Bounty Hunter:
- "Tracker II" - $210;
- "Discovery 1100" - $220;
- "Tracker IV" -$245;
- "Quick Silver" - $255;
- "Discovery 2200" - $380;
- "Quick Draw II" - $420;
- "Sharp Shooter II" - $500$.
One should select the model of "Discovery 2200 is a light and compact new series "a metal Detector to search for treasure, lost jewelry and coins". It versatile, available in the development device that allows you to search on the depth of 0.5 m, both on land and in salt and fresh water. It is equipped depth gauge and sensor adjustable sensitivity and discrimination. Three mode discriminator enable automatic exception unwanted groups of objects.
LCD monitor the detector has a clear and vivid visual identity the type of target (9 segments) in addition to the 4 tonal sound signal to different types of metals. There is an automatic setting of the ground balance.
But in some areas there are areas with high salinity soils heterogeneity and different inclusions. Such inclusion is often a metal detector reacts as a goal. To avoid such false positives can to choose metal detectors "Tracker II" and "Sharp Shooter II". They also have automatic and manual adjustment to the soil.
"Sharp Shooter II also has a static search, equipped with a depth gauge and three-mode discriminator.
If you have a budget of $ 500 for the purchase of a metal detector, it is a good choice will be "Sharp Shooter II". In it in addition to the above modes present:
- static search;
- manual tuning ground balance.
The differences of consumer properties of expensive and cheap metal detectors
And depth, and accurate determination of various cheap and expensive models. But not in such proportion as vary their prices.
Example. Coin 5 kopeck USSR:
- the metal detector company "Minelab Explorer II worth $1650 with 8 coil inch finds at a maximum depth of 29 cm;
- the metal detector company "Bounty Hunter Tracker IV for $240 with the same the size of the search coil 8 inch finds the maximum at a depth of 18 cm
The difference in detection depth 11 cm (60% more) corresponds to the difference in the cost of these detectors almost 1400$ (680%).
Thus, acquiring the device, note the following:
- First. Depth of detection in air of a large coin (silver ruble) is not can be more 35-40 cm with a standard coil D21 see an increase in the size the coil increases the depth of detection of large objects, for small coins (1 kopecks) virtually no depth increases, for large coins - increases 10-20%. Big coils degrade the detection accuracy, but increase the size capture and search speed.
- Second. Cheap and expensive devices of the same type (e.g., VLF) and with the same little coils vary in depth of detection in air. The differences can be reduced to provide the service and level of recognition of the hidden object.
- Third. The ground leads only to a decrease in the depth of detection. Than the device more perfect, the better is compensated by the harmful influence of the soil.
Accuracy of discrimination (the target separation of ferrous and non-ferrous metals) ahead expensive models of metal detectors. The Explorer II was found goal is identified by the specific conductivity of the metal, as well as simple devices, but not on the same frequency, and at 28 frequencies simultaneously. Results processed by a computer and displayed on the LCD in graphic and digital the sight and sounds of different tone and volume.
Thus, it is possible to more accurately determine the metal type, target size and depth its occurrence. In Tracker IV target irradiated only on a single frequency and identified just three sounds: a low, high pitched, intermittent ("broken") signal, as well as with a dial indicator. And still need a lot of work and time to fully master and expensive a complex detector. It is desirable to have prior practical experience in search.
Explorer II and similar capabilities as the devices are recommended for experienced search engines, behind which more than one year real search.
Metal detectors high price category, using the properties of their discriminators accuracy of identification of goals, saves time looking and extra time to dig! It's also true that the complete identification of complex goals is only possible, when the object really dug.
Author: S. L. Dubrovsky