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Rx And Tr Questions


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12 minutes ago, jasong said:

When a manufacturer talks about "power", they need not specifically refer to TX power. They might be talking about RX amplification, or using the term colloquially.

True, but in this specific case (Manticore) ML is takling specifically about transmit power as they consistently touted "50% more power to the coil" compared to Equinox.  Also, with digital signal processing it doesn't necessarily take more power to "amplify" the received signal in the sense of applying electric power to bias solid state amplification circuits, though it MAY take more processing power.  But it's really all semantics at that point...

Point is the Manticore "more power" thing was related to coil power.  And all the tradeoffs referenced by Steve in his previous post apply. 

There is also some relevant discussion in this thread: 

Since we only get the very incomplete information the marketeers feed us, it's hard to determine what any of the mumbo jumbo really means in terms of actual performance.  At this pointcwe rely solely on the documented empirical performance reports of, hopefully, unbiased, knowlegeable, and skilled end users.

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22 minutes ago, Chase Goldman said:

True, but in this specific case (Manticore) ML is takling specifically about transmit power as they consistently touted "50% more power to the coil" compared to Equinox. 

I'm not so certain about that as you are. Everything I saw just said "50% more power", with no statement about what or where. I didn't see the video with the engineer talking about it being specifically to the coil, but what I see when I look at the detector is a detector with a higher gain RX circuit. 

The Manticore must have higher gain since most users are saying they cannot run it at full gain in suburban areas. This would be on the RX side of things, not TX. RX gain introduces more EMI, not TX, and the gain/sensitivity setting is an RX function.

Also, the coil is both an RX and TX antenna. So the engineer could have simply mispoke, or was trying to dumb it down. Or maybe meat 50% more amplification power of the signal at the coil.

There would be no reason - for the reasons Steve noted - to add 50% more TX power, it'd just burn battery while accomplishing very little depth gain.

For these reasons, I'd suspect they actually mean 50% more RX gain is what is happening here. And that gain is relatively useless - as people have reported - if it comes with 50% more EMI too.

Again, I don't know for sure since I don't work at Minelab. I'm just saying what I observe here.

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13 hours ago, jasong said:

I'm not so certain about that as you are. Everything I saw just said "50% more power", with no statement about what or where. I didn't see the video with the engineer talking about it being specifically to the coil, but what I see when I look at the detector is a detector with a higher gain RX circuit. 

The Manticore must have higher gain since most users are saying they cannot run it at full gain in suburban areas. This would be on the RX side of things, not TX. RX gain introduces more EMI, not TX, and the gain/sensitivity setting is an RX function.

Also, the coil is both an RX and TX antenna. So the engineer could have simply mispoke, or was trying to dumb it down. Or maybe meat 50% more amplification power of the signal at the coil.

There would be no reason - for the reasons Steve noted - to add 50% more TX power, it'd just burn battery while accomplishing very little depth gain.

For these reasons, I'd suspect they actually mean 50% more RX gain is what is happening here. And that gain is relatively useless - as people have reported - if it comes with 50% more EMI too.

Again, I don't know for sure since I don't work at Minelab. I'm just saying what I observe here.

There is no question Manticore has higher gain but I can't see why that would require a 50% increase in power.  I also tend to believe the lead engineer/designer of ML would want to be more precise than the marketeers and I do not believe he would repeatedly put out erroneous information about a very specific aspect of the design (i.e., power to the coil).   

I do agree ML is "selling it" by touting the more power thing as fact because it implies greater capability or performance, without having to actually specify what that actually is which, in turn, enables them to hide behind the ambiguity of something that sounds impressive (so they can't be held accountable for a false performance claim).  There have been valid reasons postulated for increasing the coil power (specifically current) including as a means to improve EMI mitigation and because they had to to simply keep the transmitted magnetic field strength for the Manticore simultaneously transmitted discrete waveforms on par with single frequency transmitted field strength (though it seems Nox would need the same boost). 

Again, since ML chooses to withhold more technical information than it provides and has little regard for the intelligence of their end users based on their laughable, ambiguous marketing materials like the Equinox frequency cloud diagram that made no sense whatsoever (and were forced to amend with disclaimers and footnotes), it's indeed all just speculation and probably mostly hype. 

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I do recall the Minelab rep? engineer?, saying, "50% more power to the coil". 

When I heard that, my first thought was, "how can you practically produce such a massive increase in TX, yet no other manufacturer does that"? Then I thought, "50% more power compared to what"?

I'm just not getting why detector manufacturers are often so vague when it comes to their features. Another example of this is how they don't state what SMF frequencies are being transmitted, and how they are weighted. The common argument defending such is, "They don't want the competition to know". Except, it seems to me that with an oscilloscope or some other device, the competitor's engineers can easily figure that out. So why such secrecy and vagueness?

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People need to take a breath here.  Don't confuse the interpretation of facts with the facts themselves.  Don't confuse marketing taking off with a slogan and running with it with what one of the engineers intimately involved with the Manticore's development (Mark Lawrie) said on a YouTube video in September (while on the "European Tour").  (What did he say?  You can dig into the videos or just accept what Chase said above.)  AFAIK the only people who think/say the Manticore goes 50% deeper are those without a clue.  BTW, Lawrie also mentioned that more power was put into the processing, but he didn't give a number that I heard.  He also said the Equinox 800/600 coils were incompatible with the Manticore because the extra power to the coil required changes to the coil.

Tom Dankowski is one who gets excited when a detector gets extra depth in his very low iron content Florida soils and beaches.  He has talked about the increased depth of the Manticore vs. the Equinox 800 although I don't remember the details.  You can find his statement somewhere in this active thread on his site.

The 1.07 theoretical improvement in depth comes from the depth to the 1/6th power relationship.  (Dave Johnson talks about this too, in one of his  papers that can be found on the Fisher site -- I've linked to that enough times that I'm tired of doing that.)  1.5^^(1/6) = 1.07.  Do air tests get close to that?  IDK. 

Talk is cheap.  Doing the research (whether that means digging through YouTube videos or actually using detectors for testing) costs a bit more.

 

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On the first page of Dankowski's Manticore thread, he states:

"IF you could figure out a way to wire a EQX coil to the new Manticore...... the Manticore would blow/burn it out. Soooo...... coils are NOT interchangeable. (There's also other reasons for incompatibility).
The coil has tighter tolerances....and more stuff in it; hence, soooo........it must be built heavier-duty. The extra 2 heli-arc'd fore-aft curved ribs are not very hydrodynamic; yet, are a necessity."

"50% more power to the coil does not equate to 50% more depth."

So it sounds to me that they are for sure referring to power TO the coil.

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Fortunately, I wasn't one of the many that were concluding "50% more power to the coil", meant 50% more depth. I often answered them with, "50% more depth than the Nox? Absolutely not, and not even close. 50% more depth than a Micronta? Yes, and more so!" ?

Anyway, thank you all for the replies and links that provide more in depth information.

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Bottom line, we don't know what 50% more power precisely means, ML and people supposedly involved with the design (e.g., The ML Chief Engineer, Tom Dankowski) have explicitly stated/written 50% more power to the coil as well as more power overall, ML has explicitly stated both that the power increased is in relation to "traditional detectors" and also, explicitly mentioned the Equinox.  We know that from a physics standpoint this DOES NOT translate to 50% increased depth (not even close), and finally we can only speculate on what all of this really means or translates into regarding performance or capability.  And that's exactly where ML wants us to be - speculating on how much magic is in their latest magic wand.  Plenty of us here have seen this play out numerous times before, and it is always the same story, there are no great leaps or game changers here.  Just a well designed detector that has some desirable features that some may or may not find useful and, of course, now a higher price point.

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4 hours ago, Digalicious said:

When I heard that, my first thought was, "how can you practically produce such a massive increase in TX, yet no other manufacturer does that"? Then I thought, "50% more power compared to what"?

Just another thought, there has to be a reason why ML is doing that (they may "have" to do it for some reason) because the reason other manufacturers don't is not because they can't, but because it results in a huge penalty in run time.  ML went with a higher capacity battery to compensate for the drain just to keep run times reasonable.  Manticore AND Deus 2 have certain program modes that result in higher power drain.  So this more power thing may only be invoked during certain modes.

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