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Highly Mineralized Ground


malco

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This is real... from http://www.detectorprospector.com/metal-detecting/minelab-multi-iq-technology-details-explained.htm I have highlighted what I think you should really pay attention to.

Multi-IQ is derived from:

Simultaneous Multi-Frequency In-phase and Quadrature Synchronous Demodulation.

We can go to a statement from Dr Philip Wahrlich, our principal technology physicist, about a key difference of Multi-IQ compared to the demodulation taking place in conventional single frequency VLF detectors:

“Within the Multi-IQ engine, the receiver is both phase-locked and amplitude-normalized to the transmitted magnetic field – rather than the electrical voltage driving the transmitted field. This field can be altered by the mineralization in the soil (in both phase and amplitude), so if the receiver was only phased-locked to the driving voltage, this would result in inaccurate target IDs and a higher audible noise level. Locking the receiver to the actual transmitted field, across all frequencies simultaneously (by measuring the current through the coil) solves these issues, creating a very sensitive AND stable detector”

Precisely measuring these extremely small current variations is quite remarkable if you consider the levels involved. It’s actually parts per billion, or nanoamp signals, we are talking about here!

With Multi-IQ, we can derive much greater target ID accuracy and increased detecting performance, especially in ‘difficult’ ground. In ‘mild’ ground, single frequency may perform adequately, BUT depth and stable ID’s will be limited by ground noise; whereas the Multi-IQ simultaneous multi-frequency will achieve maximum depth with a very stable target signal. In ‘strong’ ground, single frequency will not be able to effectively separate the target signal, giving decreased results; whereas Multi-IQ will still detect at depth, losing a minimal amount of target accuracy.

Let’s hear more from Philip Wahrlich about the technical details:

“For each frequency the detector transmits and receives there are two signals which can be extracted which we refer to as I and Q. The Q signal is most sensitive to targets, while the I signal is most sensitive to iron content. Traditional single-frequency metal detectors use the Q signal to detect targets, and then use the ratio of the I and Q signals to assess the characteristics of the target and assign a target ID. The problem with this approach is that the I signal is sensitive to the iron content of the soil. The target ID is always perturbed by the response from the soil, and as the signal from the target gets weaker, this perturbation becomes substantial. With some simplification here for brevity, if a detector transmits and receives on more than one frequency, it can ignore the soil sensitive I signals, and instead look at the multiple Q signals it receives in order to determine a target ID. That way, even for weak targets or highly mineralized soils, the target ID is far less perturbed by the response from the soil. This leads to very precise target IDs, both in mineralized soils and for targets at depth.”

I can sum this up simply by saying Equinox correctly identifies non-ferrous items that previous detectors mis-identified in some way. In bad ground non-ferrous items often are incorrectly identified as ferrous. The depth at which this happens may be much shallower than people think. I can promise anyone that uses an Equinox for very long will start making good finds at depths that are shallow enough you would swear there is no way they could have been missed by so many detector for so long. But as Tom Dankowski is fond of saying, you can’t know what you are missing. Well, Equinox lets you know about at least some of what we have been missing. The depth is there also, but there is more going on here than just “more depth”.

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Thanks Steve for your reply. I'm very pleased with my CTX3030, above everything that I have tried, and I've had most VLF's and a few PI's. For my type detecting I've not found anything better. I'm not the type that is looking to be critical of someone that is trying to be helpful. However, It does seem that Minelab is claiming that the ENOX has an advantage in bad dirt. They seem to state that it is better on low conductors in bad dirt but I'm not sure if they claim it to be better on high conductors in bad dirt. Any help going forward will be much appreciated.  Thanks

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