When I took up metal detecting, I didn’t understand much, especially when I heard such words as discrimination, ground balance, mineralization, etc. I didn’t adjust the ground balance. I just turned the metal detector in and hurried to start treasure hunting. Moreover, even sometime later, I was still using automatic manufacturer’s settings, and these were quite enough for me. Only when I became a more experienced digger, I started to see how important is proper setting and adjusting of the ground balance. This is the experience I’d like to share with you here.
Contents
Soil mineralization and its influence on a metal detector
Many beginner treasure hunters often wonder why air test results from a metal detector differ from those obtained on the ground. The key issue is that the ground itself can act as interference for a metal detector, particularly in areas with high mineral content.
Understanding Soil Mineralization
Soil mineralization refers to the presence of electrically conductive materials, such as iron oxides and magnetic impurities, which can obscure non-ferrous targets. This mineralization level varies significantly, even within a single field, leading to inconsistent detector readings. Heavy rainfall or prolonged dryness can further affect soil mineralization levels, impacting metal detection results.
Types of Mineralized Soils
Certain soils, like alkali and solonetzic soils, exhibit high mineralization levels. These soils often appear lighter in color and may support minimal vegetation. Additionally, seawater is known for its high mineral content, making beach hunting with a metal detector particularly challenging without a ground balance feature.
Impact of Mineral Inclusions
Mineral inclusions can generate false signals in metal detectors, severely hampering the detection process. As a result, users may miss signals from small or deep targets, diminishing their chances of finding valuable items. In addition to mineralization, other factors such as roots, rocks, and trash can also interfere with signal detection, making it essential to research the hunting area beforehand.
The Role of Ground Balance
To mitigate these false signals, many metal detectors include a ground balance function. This feature allows users to adjust the detector to the mineral content of the soil, enhancing its ability to identify true signals from buried treasures. Some advanced metal detectors allow users to manually adjust the ground balance, while others offer automatic settings that can adapt to changing soil conditions.
Depth Sensitivity and Detector Types
High mineralization not only produces false signals but can also reduce a detector’s sensitivity to deeper targets, making it important to conduct thorough tests in different soil types. Additionally, VLF (Very Low Frequency) detectors are more affected by mineralization compared to PI (Pulse Induction) detectors, which are often used in highly mineralized environments like saltwater beaches.
Field Testing
Regular field testing of a metal detector in various soil conditions can help users understand how to best utilize their equipment and adapt to different environments.
What does ground balance influence?
If the ground balance on your metal detector is set incorrectly, it can lead to inaccurate target identification and reduced detection depth. Setting the balance is crucial for minimizing false signals caused by soil mineralization, allowing the device to detect targets more precisely.
Enhancing Detection Efficiency
A metal detector with a properly adjusted ground balance function significantly boosts detection efficiency, providing clearer signals and more accurate VDI (Visual Discrimination Indicator) numbers for targets. Ideally, you want to find the right balance between excessively high and low adjustment settings.
Consequences of Incorrect Settings
Setting the ground balance too high can cause the detector to miss valuable signals while filtering out false signals from mineralized soil. This issue is particularly pronounced if the sensitivity level is also set to its maximum. In such cases, the detector may overlook targets, mistaking them for the effects of soil mineralization.
Conversely, using low adjustment values can also hinder the detection process. If the ground balance is set too low, the detector may ignore the effects of soil mineralization, leading to a reduction in detection depth and an increase in phantom signals—false alerts caused by mineralization.
Finding the Optimal Balance
Achieving a proper balance between high and low settings will optimize your metal detector’s performance. This will enhance your detection depth and improve the clarity of target signals.
Are you looking to gain several additional centimeters or inches in detection depth? Do you want to detect a coin next to a large, corroded nail? Are you eager to receive signals from all underground targets? To increase the number of target signals you receive and to identify deeper targets, adjusting the ground balance is the key.
Setting the ground balance correctly is essential for maximizing your metal detecting experience.
Ground Balance Types
There are two primary types: manual and automatic. Manual adjustment gives users more control in challenging conditions, while automatic ground balance can quickly adapt to changing soil conditions.
Understanding Phantom Signals
Phantom signals can sometimes be confused with real targets. Understanding the ground balance helps differentiate between these false signals and actual treasure.
Sensitivity Settings
Finding the right sensitivity setting is just as important as ground balance. A well-balanced detector with high sensitivity can lead to deeper target detection but may also increase false signals.
Environmental Effects
Factors such as soil moisture, temperature, and even the presence of trash can affect ground balance settings and detection effectiveness.
Regular Calibration
It’s advisable to calibrate the ground balance regularly, especially after moving to a new detecting location or when environmental conditions change.
How often do you need to adjust ground balance?
There is no unified standard in this respect. You can do it from time to time, for example, once in an hour. Or, for instance, you can use automatic tracking of balance value.
However, all automatic controls have a drawback – in this case, the detection depth decreases if compared with a manual setting (the depth will be almost unchanged in this case). It is for you to decide, though.
How to adjust the ground balance?
Modern metal detectors typically feature three types of ground balance: fixed, manual, and automatic. Understanding these options can greatly enhance your metal detecting experience.
Fixed Ground Balance
Fixed is a pre-set value that cannot be changed by the user. It is adjusted at the factory and provides a rough calibration suitable for entry-level metal detectors. While this type of ground balance allows beginners to start detecting right away—simply by turning on the device—it has limitations. The detection depth and sensitivity to small targets are significantly lower compared to metal detectors equipped with manual or automatic functions. Consequently, more experienced detectorists usually avoid fixed ground balance models as they seek greater performance and precision.
Manual Ground Balance
Manual ground balancing allows the user to adjust settings based on the conditions of the soil being searched. This adjustment can be performed by listening to the ground signal and setting the ground balance accordingly. Some devices offer an initial automatic calibration when the search coil is waved above the ground, which can then be fine-tuned manually. This approach is often more effective, particularly for those who understand how their detector behaves in various conditions and soil types. By first utilizing the device’s automatic adjustment and then refining it manually, users can achieve optimal performance.
Automatic Ground Balance
Automatic ground balance takes the guesswork out of adjustments. In this mode, the device automatically decides whether to engage the function based on real-time conditions. This feature is especially valuable in areas with complex soils, where mineralization can vary significantly. While automatic ground balance can simplify the detecting process, it may not always provide the same detection depth as manual adjustments.
How do I set the ground balance?
I try to get the lowest ground balance value, but at that, my metal detector (XP Deus) shouldn’t produce any false signals. I use one trick, which an experienced treasure hunter taught me once.
Here are the stages:
- I find an iron-free area.
- Dig not very deep pit (half spade’s depth or more).
- I wave the search coil above the pit and listen. If the detector produces signals, I increase the value.
- I continue doing so till I find the value at which the metal detector doesn’t react on the pit in any way.
- During the metal detecting process, I shift the value higher or lower, depending on the device’s performance stability.
I’d say that when using this approach, you receive lower values than in the case of automatic or manual ground balance adjustment. At the same time, the detection depth increases as well. You are welcome to try the approach mentioned above. Maybe it will work for you.