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XP Deus 2 Vs Minelab Equinox 800 Depth Test Emi Under Control


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You are in a really tough situation battling both EMI and highly mineralized ground in your home area.  And its a catch-22 where the multi-frequency helps with the difficult soil, but at the same time is susceptible to EMI.   The same happens to the Equinox in the video, though it seems to handle things slightly better in this example.

The Deus 2 seemed more stable at a sensitivity of 80 in this video, compared to your other one running it much more maxed-out.  I think its more of a realistic sens. setting for where you are testing.  Very helpful info for me.  I run my Equinox 800 generally between 18-20 sens. where I hunt coins in city parks, so I can imagine I'd need to drop sensitivity a lot like you have in the video if I were to run a Deus 2 in my conditions.  

Thanks for running a second test on lowered settings and sharing your findings again.   

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Why the heck there is not an EMI receive coil built into the controller to cancel out EMI leaves my mind boggled. Sure the detector may lose some depth or targets occasionally but it would silence most of this flute insanity.

 

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1 hour ago, burlguy said:

Why the heck there is not an EMI receive coil built into the controller to cancel out EMI leaves my mind boggled. Sure the detector may lose some depth or targets occasionally but it would silence most of this flute insanity.

Yeah, why not just “cancel” that EMI? Easy, right?

Every EMI signal mimics a portion of the target response spectrum, and eliminating it eliminates the responses from certain targets also. It’s possible to isolate an EMI response on a single target id number, or range of numbers, and simply notch them out. But then you lose those targets. Or you can reduce general sensitivity, but now you lose depth across the board - notching may be preferable in many cases.

There is no methodology for reducing or eliminating EMI that does not come at some kind of cost in the form of lost depth or targets when running SMF detectors. The best bet whenever possible is to be operating on a frequency or frequencies totally outside of whatever is causing the interference, even to the point of using a different detector, if need be. I’ve found 19 kHz single frequency units to be among the most trouble free detectors I’ve used, when it comes to common EMI issues in U.S. urban locations.

I tend to prefer detectors that go nuts when encountering EMI. At least I know about it, and can maybe do something about it. Some older units, in particular, suffered from “silent EMI,” where you simply lost depth or targets in the presence of EMI but had no idea it was happening. The Fisher CZ machines are kind of famous for this issue.

 

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5 minutes ago, Steve Herschbach said:

Yeah, why not just “cancel” that EMI? Easy, right?

Every EMI signal mimics a portion of the target response spectrum, and eliminating it eliminates the responses from certain targets also. It’s possible to isolate an EMI response on a single target id number, or range of numbers, and simply notch them out. But then you lose those targets. Or you can reduce general sensitivity, but now you lose depth across the board - notching may be preferable in many cases.

There is no methodology for reducing or eliminating EMI that does not come at some kind of cost in the form of lost depth or targets when running SMF detectors. The best bet whenever possible is to be operating on a frequency or frequencies totally outside of whatever is causing the interference, even to the point of using a different detector, if need be. I’ve found 19 kHz single frequency units to be among the most trouble free detectors I’ve used, when it comes to common EMI issues in U.S. urban locations.

I tend to prefer detectors that go nuts when encountering EMI. At least I know about it, and can maybe do something about it. Some older units, in particular, suffered from “silent EMI,” where you simply lost depth or targets in the presence of EMI but had no idea it was happening. The Fisher CZ machines are kind of famous for this issue.

 

With todays speed of processors there is certainly a way of removing a vast majority of the unwanted air signals that mimic wanted signals/targets.

Most of the time when experiencing EMI, target signals will still show up stronger than the unwanted EMI. Obviously there will be the impossible situations, buried dog fences, high voltage eddy currents, etc.  But so much of the chatter can be eliminated with some focused engineering. 

 Taking a constant environmental sample away from the transmit and receive signal could go a long way in reducing this. Offsetting frequency is not nearly enough for most situations. I am sure its being worked on, in fact I know its being worked on.

Subtraction of data from white gaussian noise is how are cutting edge long distance radar is now identifying threats. We may see something similar where EMI is no longer a problem but a way of helping define targets. Sufficient processing power will be needed, perhaps we will see quantum detectors?

 

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If you are going to notch, notch volume is the way to go, that way you do not completely lose those targets.  On some machines the notch attenuation also brings a distinct change in tone or pitch, allowing the ability to obtain worthwhile reference toward dig no dig decisions. So I have heard. Literally.

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I'm finding deep HC to be the most manageable for EMI. Any program with the higher KHz spread is the worst, which unfortunately is most of the programs. Some of the EMI I'm encountering had no rhyme or reason to it. Comes and goes. Sensitivity down to 80 one minute and then gone. Turn up Sensitivity and a few minutes later it's super bad again.

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52 minutes ago, burlguy said:

With todays speed of processors there is certainly a way of removing a vast majority of the unwanted air signals that mimic wanted signals/targets.

Most of the time when experiencing EMI, target signals will still show up stronger than the unwanted EMI. Obviously there will be the impossible situations, buried dog fences, high voltage eddy currents, etc.  But so much of the chatter can be eliminated with some focused engineering. 

 Taking a constant environmental sample away from the transmit and receive signal could go a long way in reducing this. Offsetting frequency is not nearly enough for most situations. I am sure its being worked on, in fact I know its being worked on.

Subtraction of data from white gaussian noise is how are cutting edge long distance radar is now identifying threats. We may see something similar where EMI is no longer a problem but a way of helping define targets. Sufficient processing power will be needed, perhaps we will see quantum detectors?

Yeah, it’s not like I’d know anything about any of it anyway, so I cede the floor to you. :smile:

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39 minutes ago, Steve Herschbach said:

Yeah, it’s not like I’d know anything about any of it anyway, so I cede the floor to you. :smile:

No... Thats never my intent or my thought process. You have done way too much for the community and I have contributed very little. I thought it was open mic...

But I do like to think outside the box and this has done very well for me. 





 

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