Will The Next Gen Detectors Address Emi ???

[Jeff McClendon]

18 hours ago, Digalicious said:

On both my Vanquish 540 and my Legend, noise cancel does basically nothing. I've also watched countless detecting videos, and it didn't matter if they were using the 540, 800, Legend, or D2, because not once in any of those videos did the noise cancel do anything either.

💤

[phrunt]

Anyway, as has been noted with the Deus 2 Silver slayer program I do a similar thing on my Ace 300i, it's 10kHz can be a troublesome frequency for EMI in some spots and as all I want to find are silver coins I just notch out everything below the last couple of notches where the silver coins reside, it's been a successful approach and makes a detector that otherwise wouldn't find these coins by lowering sensitivity be able to find them.    It has a frequency shift option but the shift isn't large enough to move itself off the EMI frequency.

It's default coin mode removes a lot of the notches that the EMI falls into by default, but by just keeping the last two notches it virtually eliminates all EMI falsing and I don't feel performance is hindered, I still pull 10+ inch silver coins and our NZ $1 and $2 coins so I can buy lunch or dinner on the way home from the hunt with coins I found 🙂

 

[Digalicious]

9 minutes ago, Jeff McClendon said:

💤

In other words, you have nothing to counter my points (either theoretically or empirically), so as usual, you resort to veiled insults and Red Herring arguments. It's rather childish and pathetic.

[Jeff McClendon]

Just now, Digalicious said:

In other words, you have nothing to counter my points (either theoretically or empirically), so as usual, you resort to veiled insults and Red Herring arguments. It's rather childish and pathetic.

Nice projecting Digalicious.

[Digalicious]

34 minutes ago, phrunt said:

Anyway, as has been noted with the Deus 2 Silver slayer program I do a similar thing on my Ace 300i, it's 10kHz can be a troublesome frequency for EMI in some spots and as all I want to find are silver coins I just notch out everything below the last couple of notches where the silver coins reside, it's been a successful approach and makes a detector that otherwise wouldn't find these coins by lowering sensitivity be able to find them.    It has a frequency shift option but the shift isn't large enough to move itself off the EMI frequency.

 

Exactly.

One way or another, if EMI noise reduction has to work via software, then that means filtering of some form. Which also means the "give and take" we often talk about, will come into full effect. 

[jasong]

1 hour ago, Digalicious said:

The cheap power chips haven't just been in abundance "today". They've been around for a good couple of decades. Yet, the engineers haven't incorporated real time EMI filtering. I think they haven't done so because it wouldn't make any difference. 

Detector engineers didn't incorporate anything modern into metal detectors for decades. It's a recent development, relatively speaking.

No offense to detector engineers, but aside from Minelab, or maybe a few other companies recently, most of these machines looked like stuff designed by electronics techs and hobbysists turned pro, not by a team of PhD electrical engineers, computer scientists, and physicists. 20 years ago, fresh out of school and ready to change the world, I asked on a forum why everything seemed primarily analog still and no one was really using modern MCU's with built in signal processing - I was told there was no reason to, by actual detector engineers. And the companies proceeded to release the same models with old circuitry and new names/paint for another 10 years while tech was making great leaps forward, and some went out of business because of it. Detectors are always 10-15 years behind the rest of tech. In some case, more - some of those old detector designs were straight out of the 80's or early 90's and 30-40 years behind the time. 

Now we've moved beyond basic MCU's and we have ultra customizable FPGAs and whatnot, with many magnitudes more power. And even that is on the cusp of being "old news" IMO. Honestly, I think a lot of digital hardware approaches are about to be obsoleted by AI signal processing. 

I've seen first hand some of the magic you can do with modern tech with a team of qualified, educated people working on products. The company has to be willing to pay for that skillset though, it takes a whole team now. Most US detector companies never were, until maybe recently. I wouldn't count Minelab out though, as much as they frustrate me, I have to hand it to them for staying modern and supporting their own science/engineering grads in a way US companies refused to, and they are reaping the benefits of it. They are suffering from the ill advice of their modern marketing grads now though, but that's a different story. 😅💩

Meanwhile, for any companies willing to pay for real development, EMI/noise mitigation is IMO definitely one of the areas detectors can absolutely still benefit and improve by large leaps, just my opinion but I'm pretty sure of it. 

[Digalicious]

5 minutes ago, jasong said:

 

Meanwhile, for any companies willing to pay for real development, EMI/noise mitigation is IMO definitely one of the areas detectors can absolutely still benefit and improve by large leaps, just my opinion but I'm pretty sure of it. 

I obviously agree that large leaps need to be made in EMI mitigation, because I see current EMI mitigation to be almost laughable. What I can't see however, is how it can be legitimately accomplished with software, without an equal negative effect occurring.

In regards to the rest of your post, well those are great points. Something else to consider is that hobbyist detecting is a niche market. Coins are diminishing and more and more people are wearing cheap jewelry that looks as good as the real thing. Due to those, I can see veteran hunters prematurely giving up, and new detectorists becoming frustrated and giving up. If all that is taken into account, as well as what you said, then I imagine there is little desire to put profits into substantial R&D.

[jasong]

37 minutes ago, Digalicious said:

Coins are diminishing and more and more people are wearing cheap jewelry that looks as good as the real thing. Due to those, I can see veteran hunters prematurely giving up, and new detectorists becoming frustrated and giving up. If all that is taken into account, as well as what you said, then I imagine there is little desire to put profits into substantial R&D.

Ever since I started detecting there were always arguments that there was no payoff in R&D though, which is why some US companies stagnated, yet Minelab proved them wrong.

But it does feel different this time, feels the growth curve is bending downwards now. So I agree, we'll probably see decreasing R&D too, unfortunately. 

Nugget depletion is a one way, irreversible vector. It's why I've spent so much time diversifying into geology and using the detector as a tool to help identify larger, commercial deposits. I'm not sure there is an equivalent for coin/jewelry/relic detecting though, it'll likely decrease in growth too. Meteorites are an interesting case that gets replenished however, and can be quite valuable, but they are highly niche and require a ton of patience to find, not for most people.

[GB_Amateur]

1 hour ago, jasong said:

Meteorites are an interesting case that gets replenished however, and can be quite valuable, but they are highly niche and require a ton of patience to find, not for most people.

What's the replenishment timescale, though?  (You know better than I that...) there are a couple strewn fields at Gold Basin which have produced quite a bit, yet those falls occurred thousands of years ago, I think.  We hear about fireball sightings and their subsequent meteorite searches, but how frequent are those -- about as frequent as Medieval Europe cache finds?  I read a  decent book (Field Guide to Meteors and Meteorites by Norton and Chitwood -- for some reason I can seem to find the link atttach icon in the post headings...) on the subject and it surprises me the low number of estimated falls and even recovered samples listed for the various known finds by classification.  And many of those, like the Gold Basin finds, are from falls which occurred long ago.

There are things quoted about the number of tons of meteoroid material that hits the earth's upper atmosphere everyday.  However, how much of that makes it to the surface and what is the resulting size distribution?   (BTW, these questions are more than rhetorical.  I've looked for answers to them and not been successful.  Someone has at least a reasonable idea; maybe even someone here.)

Maybe getting off-topic here, but from much of what I've read on this thread, there's a good reason for that.  😄

[UT Dave]

10 hours ago, UT Dave said:

One of the absolute worst parks for EMI is the one closest to my house.  I have to run the Nox at 20Khz and sens 16 to get it to quiet down.  Maybe I'll take them both over there this afternoon and do a side by side to satisfy some of my curiosity.

Didn't quite happen.  I took both machines over there, but was short on time and wanted to get in a quick hunt with the Manticore then do a side by side EMI comparison before leaving.  Started raining about an hour in and when I got back to the truck I didn't feel like standing out in the rain to compare EMI.

Manticore in Multi, ATG, default ferrous limits, one region all tones, ran quiet and stable at 18-21 sensitivity depending on which part of the park I was in.   And just nailed the nickels.  I continue to be impressed with how easily the Manticore calls nickels over the 800.  And I think the 800 calls them pretty good.  But I only dug 18 coins and 9 of them were nickels and I dug only 2 square tabs that were both only half a square tab.  One junk stainless and one mangled .925.  

Since, I don't know for anything like a fact that Manticore sensitivity 20 equals Nox 800 on 20 sensitivity, a static comparison would have been uncertain anyway.  Comparing wild targets both tuned for EMI would be a lot better.  But, honestly, I don't see myself bothering.  I'm feeling pretty confident the Manticore is working better in EMI and would rather just hunt with it than do tests against the 800.  I likely will still do the static compare at this park anyway, it's easy and won't take long.  Just need it not to rain 😁.

- Dave