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Good afternoon. A question for specialists about the operation of the device on difficult ground with different TX contours. What do you think about this - suppose one coil: loop current 200 mA, peak-to-peak 15V, 200x15=3000 (let there be field power), the second coil current 100mA, peak-to-peak 30V, 100x30=3000. Which reel will work best on difficult ground and why?
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The transmit coil is not a resistor, you cannot simply multiply voltage by current and start making comparisons. -
You are correct that in the context of a transmitter coil, the concept of field power is not as straightforward as simply multiplying voltage and current.
When analyzing the performance of a metal detector's transmitter coil, several factors come into play, including the coil's inductance, resistance, and the magnetic field it generates. The relationship between voltage, current, and the resulting field strength is more complex.
To determine the effectiveness of a coil on difficult ground, it's crucial to consider factors such as soil mineralization, conductivity, and the presence of various types of metals. These factors can affect the coil's ability to generate a magnetic field and its sensitivity to different targets.
Comparing two coils solely based on their voltage and current may not provide an accurate assessment of their performance on difficult ground. It's essential to consider additional factors, such as the coil's design, shape, size, and the specific characteristics of the ground being scanned.
To determine which coil would work best on difficult ground, it would be more appropriate to evaluate their performance based on field tests, sensitivity to different target sizes and depths, and the ability to discriminate between various types of metals. Practical experimentation and comparative analysis would provide more reliable insights into the performance of different coil configurations on challenging terrains.
Here's the summary of the initial answer:
In the scenario, you presented, with two transmitters (TX) coil configurations:
Coil 1: Loop current 200 mA, peak-to-peak voltage 15V (field power = 3000)
Coil 2: Loop current 100 mA, peak-to-peak voltage 30V (field power = 3000)
Coil 1 has a lower voltage but a higher current, while Coil 2 has a higher voltage but a lower current. Generally, higher currents can provide better sensitivity for smaller targets closer to the surface due to increased magnetic field strength. This could be advantageous for detecting small or shallow metal objects.
On the other hand, higher voltage can enhance depth penetration, allowing the detection of larger or deeper objects. However, a lower current might reduce sensitivity to smaller or shallow targets.
Considering the challenges of difficult ground, a coil with higher sensitivity would generally be preferable. Therefore, in this scenario, Coil 1 with its higher current may offer better performance on difficult ground, especially for detecting smaller or shallow targets.
Please note that these are general considerations, I just try to write. I'm still new to this.Comment
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Excuse me, are you serious? coil and resistor are two different things the answer just opened my eyes....))))Originally posted by Skippy View PostComment
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Coil voltage does not matter, it's just a means to an end. TX field strength is proportional to ampere-turns = the coil current times the number of turns. However, it's a bit more complicated and the voltage drive, peak current, and coil design all go hand-in-hand.Comment
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All right. I'm talking about field strength. But after all, the same tension can be achieved in different ways, coming out of: the number of turns, the diameter of the wire, the capacitance of the capacitor.Originally posted by Carl-NC View PostComment
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Correct, that's why there are so many different metal detector designs. There is no one "right way" to do it.Originally posted by Artyom View Post
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There is a major issue with high Tx power, in that the ground mineral matric becomes more significant in the recieved signal. It is possible to completely saturate the ground matrix which in turn, will so imbalance the coil the sensitivity will drop off to nothing. I suppose that active nulling of the coil might help, and on that point, saturating the ground matrix fully might not be such a bad thing, as once you put enough power out, you can compensate for the saturation using clever software.Comment
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