Interesting observation on the question of "see through" and coil options:

[Tom_in_CA]

Re.: the 3030 "tracing" 2 targets, etc... Let's put that aside for the moment, and concentrate solely on sound. Because frankly, while that's a nifty trick that the 3030 does, yet I don't see how that's going to help. Since the primary reason that causes a person to stop to look at their screen TO BEGIN WITH, is: the audio signal they're hearing. So unless you heard an audio signal worth investigating to begin with, no one's going around watching their screen all the time. Till they've gotten a signal. So let's put that aside, and talk about sounds alone:

You seem to be saying that no machine can average. That they're *only* going to get it if there's a peak at it, which therefore falls under a "separation" issue, not an "averaging" issue. Am I understanding you correctly ?

If so, do the following test with both your CTX and your 705:

1) Take a quarter sized piece of foil and a clad dime. Since the quarter sized foil is a large physical shape, and will allow no "peak" at the smaller coin behind it.

2) Set the disc. bins to *just* where you loose the foil. So that it nulls.

3) Now with a dime behind that foil (so that it's totally hidden by the foil with no "peak"), wave the targets. Try both with a space between the targets, and/or touching.

 

[Digger]

Re.: the 3030 "tracing" 2 targets, etc... Let's put that aside for the moment, and concentrate solely on sound. Because frankly, while that's a nifty trick that the 3030 does, yet I don't see how that's going to help. Since the primary reason that causes a person to stop to look at their screen TO BEGIN WITH, is: the audio signal they're hearing. So unless you heard an audio signal worth investigating to begin with, no one's going around watching their screen all the time. Till they've gotten a signal. So let's put that aside, and talk about sounds alone:

You seem to be saying that no machine can average. That they're *only* going to get it if there's a peak at it, which therefore falls under a "separation" issue, not an "averaging" issue. Am I understanding you correctly ?

If so, do the following test with both your CTX and your 705:

1) Take a quarter sized piece of foil and a clad dime. Since the quarter sized foil is a large physical shape, and will allow no "peak" at the smaller coin behind it.

2) Set the disc. bins to *just* where you loose the foil. So that it nulls.

3) Now with a dime behind that foil (so that it's totally hidden by the foil with no "peak"), wave the targets. Try both with a space between the targets, and/or touching.

Regarding your comment: lets concentrate solely on sound..........I can't put your comments aside because they are not true. It isn't a "Trick" with the CTX. And if you think it is, you must not understand how to implement the technology supporting the CTX. When you properly operate your CTX with Ferrous Coin Target Separation, you can hear the audio response of a coin, even if the coil is passing over a ferrous target at the same time. Ferrous-Coin Separation uses advanced signal processing techniques to minimize the blending of ferrous and coin type target signals, even when they are on top of each other. Sure, Target Trace and Target Trace Pinpoint enhance the TID. But the audio response is what catches your attention if you hunt by ear, like I do.

I didn't say anything about requiring a "peak" to produce an audio response. What I said was: the X-TERRA does an excellent job of target separation. But if there is a large ferrous target directly over the top of a small conductive one, it ain't going to happen. (the smaller target will not produce an audio response) It has to do with the fact that the larger ferrous target may not allow transmit signals to be induced into that coin. If Transmit signals don't reach the coin, it can't respond to the receive coil. It has nothing to do with separation or averaging. It is called target masking. And it can happen with any detector out there.

As to your suggestion that I said no machine can average....Apparently you did not understand me correctly. I did not say that there weren't any machines that could average. Most of us who understand the functionality of the X-TERRA can attest to the fact that simultaneous, multiple targets will produce mixed audio tones and fluctuating TID's. On the AT Pro, I would find that passing over a nickel and quarter buried together, the audio response was generally related to the nickel. But the TID numbers were averaged to the upper 60's to lower 70's. On my CoinStrike, you actually press and hold the Disc/All Metal button to implement TID Averaging. On my XLT, I could set the display function to have Graph Averaging ON. Same thing on my Dual Frequency XLT (aka DFX). The list goes on and on. But there are a lot of detectors that use "averaging" to stabilize target ID.

It is late now. But I'll try your aluminum foil and clad dime tests on the CTX and X-TERRA tomorrow. In the meantime, if you get a chance, try one based on what I said........Set your X-705 up with Auto NC, Auto GB, 25 - 28 Sensitivity, and an open screen. Take a dime and lay it on the ground. Now lay a metal cake pan over it. Let me know how well the target averaging works when a target is completely covered by that larger, ferrous target. HH Randy

 

[Tom_in_CA]

Digger, I'm trying to understand you. The "trick" I was referring to is the "target trace visual screen thing (where a 2nd target cursor is seen floating around your visual screen). And I suggested we put that "trick aside" as irrelevent to this conversation, since we ALL go by audio first, before even looking at the screen. You say:

Regarding your comment: lets concentrate solely on sound.................I can't put your comments aside because they are not true. It isn't a "Trick" with the CTX .....

But then you turn right around and say you DO rely first on audio:

.....But the audio response is what catches your attention if you hunt by ear, like I do.

-------------------------------------------------------

Next you say:

the larger ferrous target may not allow transmit signals to be induced into that coin. If Transmit signals don't reach the coin, it can't respond to the receive coil. It has nothing to do with separation or averaging. It is called target masking....

Huh ? What do you mean that "masking" has nothing to do with "averaging" ? If a machine "averages" better, THEN THAT HELPS TO OVERCOME THE MASKING EFFECT. So it seems to me that "averaging" vs total "masking" have EVERYTHING to do with each other, for this topic

-----------------------------------------

Set your X-705 up with Auto NC, Auto GB, 25 - 28 Sensitivity, and an open screen. Take a dime and lay it on the ground. Now lay a metal cake pan over it. Let me know how well the target averaging works when a target is completely covered by that larger, ferrous target.

Haha, well how about this: I'll put a dime on the front seat of a 1955 Chevy. Then I bet I have a machine *so good* that I can detect the dime from OUTSIDE THE CHEVY! I mean, c'mon digger, you know we're talking about individual nail or two, and individual tab or two (true life hunt dilemas) for situations where a person hopes to not mask. No one is asking to be able to detect through entire pie pans, or chevys.

 

[Digger]

I started this X-TERRA forum when the X-TERRA was first introduced. As one of the Field Testers, I was quite familiar with the technology and application. A couple years later, I wrote the eBook because I was trying to help others get a better understanding for their X-TERRA. But the manner in which you have been misguiding this string of posts is the reason I have nearly stopped contributing to these websites. If folks are interested, they can go back through this string of posts and see how this all transpired.
I didn't bring up the term "averaging". You did. And then you accuse me of saying that no detector would average. When I mentioned that the CTX could see multiple targets under the coil simultaneously, you were the one who said you didn't want to talk about the CTX being able to see multiple targets on the screen simultaneously, referring to it as a "trick". I merely explained that it wasn't a trick, but had the capability of doing it both visually and audibly. So then you wanted to only talk about the audio capability for multiple targets, and I addressed that by saying that FE/CO separation would provide the audio tone of the conductive target. I commented, as I have for years and years, that I like to hunt by ear. And I think most successful detectorists would likely agree. I specifically said the X-TERRA could not see through one metal target to analyze another. But I said it could "look around the corners" with the best of them. You turned that around by commenting that I didn't think masking has anything to do with averaging. Anyone who knows how a metal detector works would understand there is a difference between eddy currents being generated from an induced electromagnetic field, opposed to a target not being able to receive those eddy currents. I was talking about a large metal object covering a smaller object. Then you tried to make it sound like I was talking about a coin laying in a few nails. That is not what I said! Targets adjacent to one another can all create eddy currents, when energized. Proper coil choice, combined with a proper skill set, can separate those target signals. But, a target signal will not be generated if that target can't be energized. And if a large ferrous object is laying completely over the top of a small conductive target, which is what I said from the beginning, that small conductive target will not be energized, thus not produce a target response.

I will end my "contribution" to this series of posts by reiterating what I said in the first sentence. I have grown tired of people twisting and turning comments made by one person, into something entirely different. I don't why some people are compelled to do that. But with the growing disregard I have for those who seem to take pleasure in belittling other's efforts, I just don't care to participate.

 

[Old Longhair]

Great posts Randy!
I was watching to see how this would all shake down. I agree with everything that Randy stated, as I have experienced it on occasions too numerous to count.
I would also add, that one thing that Minelab machines in general excel at is the ability to still lock onto faint, weak, or combined conductive/ferrous tones at very slow sweep speeds. I believe that it is the reason that they "look around corners" so well. Machines that require faster sweep speed are far more likely to "skip over" good targets that "peek out" along the edges of trash that masks them. It's not that Minelab machines are slow, but rather that they enjoy their successes due to their ability to go slow and not miss what machines perceived to be "faster" miss.

I enjoy and appreciate hearing from people that actually know about the technology at a level beyond the average hobbyist as Randy does.
Thanks Boss! Keep it coming!

 

[Tom_in_CA]

Digger, I apologize for offending you. All definitions of "eddy currents" and "average" and "peak" and "masking" and such aside, all I know is that some machines will not get conductive targets under nails (while they may be killer deep-seekers for beach, turf, etc..). And other machines ( that might be considered wimpy for depth) can go into a ghost-townsy nail riddled environment, and pulls coins out from under nails.

So I'm sorry to bog you down in defintions, and to have picked on things you said in the midst of my trying to understand. I'm just trying to get to the bottom of how the 705 fits into that spectrum of pros & con's. And which coils do that venue of task the best . Ie.: 1) seeing through nails and 2) seeing through low conductors to get high conductors. Ie.: to minimize masking.

Sorry that the conversation became confrontational. So please don't leave the conversation, and I will tone down my way-of-challenge.

 

[Old Longhair]

And which coils do that venue of task the best . Ie.: 1) seeing through nails and 2) seeing through low conductors to get high conductors. Ie.: to minimize masking.

I'll take a shot at this one.
IF high conductors are the primary target, then most often a lower frequency coil is best. Years ago George Payne determined that the best response from a silver dime was garnered from a transmit frequency of 2.7kHz. So, the 3kHz coils for the Xterra come closest. Now which of these three authorized coils do you want? The 15" DD All Terrain From Coiltek is a great coil for depth and coverage. I often use it to locate old home sites in fields, and for the first run over it to find easy pickings. If trash density isn't too bad I'll go from that to the 9" concentric Minelab coil, so as to get between more trash w/o sacrificing too much depth. Then I'll go to the 6" DD Digger from Coiltek to hunt the absolute worst of it, knowing that I may lose some depth, but at the benefit of being able to search the edges of objects trying to mask high conductors and finding more goodies.

When I first obtained the 6" DD "Digger", I took it to two of the worst sites that I could think of. It produced at both places. It's in the write-up that I did on it.
http://www.coiltekmanufacturing.com.au/links/testimonials-x-terra/2013-jan-xterra-testimonial/

 

[Mark in S.E. IA]

Tom, do you know what this whole thing boils down to..... The guy with the X505 and the HF 6" coil knows more about what his MDer is trying to tell him then you do with your X705 and 9" MF coil. I would bet money that if you got a 6" HF coil and you an that other guy with the X505 went back to the ghost town he would still kick your butt because he is better at knowing what his MDer is trying to tell him. You can do all the air test you want to but it's just not the same as the real world, MDing in the dirt....

 

[Tom_in_CA]

I understand that lower frequencies = better for high conductors. But how are they, on the 705, with averaging ? So like if you :

a) put a dime or quarter behind a nail in an air test ?

b) put a dime or quarter behind a pulltab (or two) ?

 

[Tom_in_CA]

We might be meeting up this coming Saturday at the site. We'll both have 6" HF coils on our machines. And we'll check over "flagged targets", to see if they're bringing-it-in-the-same. *IN THEORY* , they should both be capable of the same, right ? And if one seems to lag on not getting the signal as strong or clear, we can adjust the settings up and down, etc....

In theory, the machines should perform the same over flagged in-the-ground-tests, since the 705 and 505 can be set up the same (assuming auto-track GB not needed).

I'll report back on the results.

PS: This test will also possibly be comparing a Racer and a Dues as well. Each of the is also said to be the "cat's meow" in iron riddled sites.

 

[Old Longhair]

Tom, do you know what this whole thing boils down to..... The guy with the X505 and the HF 6" coil knows more about what his MDer is trying to tell him then you do with your X705 and 9" MF coil. I would bet money that if you got a 6" HF coil and you an that other guy with the X505 went back to the ghost town he would still kick your butt because he is better at knowing what his MDer is trying to tell him. You can do all the air test you want to but it's just not the same as the real world, MDing in the dirt....

Bingo! And until the Coiltek 6" DD came along, the 6" HF was the smallest DD coil available, so that's what he learned to use.

We might be meeting up this coming Saturday at the site. We'll both have 6" HF coils on our machines. And we'll check over "flagged targets", to see if they're bringing-it-in-the-same. *IN THEORY* , they should both be capable of the same, right ? And if one seems to lag on not getting the signal as strong or clear, we can adjust the settings up and down, etc....

In theory, the machines should perform the same over flagged in-the-ground-tests, since the 705 and 505 can be set up the same (assuming auto-track GB not needed).

I'll report back on the results.

PS: This test will also possibly be comparing a Racer and a Dues as well. Each of the is also said to be the "cat's meow" in iron riddled sites.

With Tracking enabled, the 705 should have an advantage. Tracking is far more accurate, faster, and consistent than you can be. That equates to more accurate, consistent, repeatable signals.

What frequency will you test the Deus in?

 

[Tom_in_CA]

.... With Tracking enabled, the 705 should have an advantage. Tracking is far more accurate, faster, and consistent than you can be. That equates to more accurate, consistent, repeatable signals. .... What frequency will you test the Deus in?

long-hair: If you look at the instructions on the 705, it says that tracking auto-GB is *not* recommended for sites riddled with iron. Because the machine can eventually start to treat the abundance of rusty iron in the soil, as part of the ground's make-up (ie.: mineral content) ITSELF. And that will cause eventual muffling of conductors trying to peak through & around. Ie.: a "dumbing down", so-to-speak.

This has been my experience with any other machine that can auto-track, is that you want to turn the feature OFF for such a venue. Keep it in manual and lock.

As for the frequency of the Deus: I am not the one who will be operating that. It will be another fellow, who is reknowned in CA circles for relicky site hunting. So I don't know how he intends to use it, nor do I know anything about the Deus personally (never tried one).

 

[Old Longhair]

long-hair: If you look at the instructions on the 705, it says that tracking auto-GB is *not* recommended for sites riddled with iron. Because the machine can eventually start to treat the abundance of rusty iron in the soil, as part of the ground's make-up (ie.: mineral content) ITSELF. And that will cause eventual muffling of conductors trying to peak through & around. Ie.: a "dumbing down", so-to-speak.

Nowhere in the manual could I find it say that, nor has it been my experience. I would imagine that the frequency selected as well as that frequency's response to the troublesome objects would be factors as well.
Also, you should read up on the use of Tracking Offset, which can be very beneficial in certain circumstances where mineralization is higher, or where due to the prevalence of iron (or other factoring conditions) you want a more dramatic audio contrast.

 

[Tom_in_CA]

long-hair, thanx for the input. I'll dig out my manual, and post the exact page and text in a little while.

As for the "off-set", if it's anything like other machines of the past that had that, I never cared for that option. I would prefer to just "add a few clicks" off-set to my own manual adjust. But when it comes to auto GB offset, I never really cared for that with machines like the Eagle, XLT, etc... that offered that.

But assuming that manual locked GB is the way-to-go in iron-ridden environments, then that's sort of a moot point anyhow. Because the user can simply "sweeten it" as they adjust manually. I found myself doing this already, by second nature, with the 705 on its maiden voyage to this nail site: I would wait till I finally got a hint of something peaking through. Then before digging it, I'd stop, and try rocking my GB setting up and back, purposefully, to see which exact setting brings in that target the boldest/clearest.

So like if I tried rocking the GB way DOWN, then I'd notice that the signals cleared up, nails weren't as loud, etc... And yes the conductive signal would still be there, but would be more faint now. Doh! Contrast to OVER-ADJUSTING the GB positive (like maxing it out all the way), and perhaps the conductor would not be screaming. Yet then every frickin nail around it was also "screaming " too. Too much snap/crackle/pop ! haha. So then I'd lower back down, for the *perfect* happy medium So in that sense, I've found the perfect off set, for the actual conditions.

Ok, I'll try to find that page out of the instruction manual for you ......

 

[Tom_in_CA]

Page 42 of the manual, down under the "tracking" section:

"As tracking ground balance constantly updates the ground balance automatically, repeated passes over a target may result in the detector balancing to the target, instead of the ground, diminishing the target signal....."

While I realize this isn't *exactly* what I'm saying about tracking to iron (as if iron-content were part of the minerals/content of the ground), yet you can see the concept is the same. If the patch/section of ground you're in is one giant spread of iron (ie.: an almost "constant" signal) , then the above instruction part would apply. This is also true of other machines with auto GB: Not advisable in iron riddled environments. Better to "lock".

 

[Old Longhair]

No, I can't see that the concept is the same. Hovering over a target isn't the same. The very next paragraph after what you quoted says, "It is recommended that Tracking Ground Balance is toggled off when a target is detected". It does not say that you need to turn off Tracking to locate a target. And to be perfectly honest, I've never encountered targets being "balanced out" by the Tracking feature, no matter how hard I've tried to do just that. With a low frequency coil there is simply enough contrast in the response that the machine recognizes that it hasn't been an issue, and I hunt in virtual beds of square nails often.

 

[Tom_in_CA]

.... Hovering over a target isn't the same....

Why can't the ... "a target" be the continuous spread of iron ?

.... I've never encountered targets being "balanced out" by the Tracking feature, no matter how hard I've tried to do just that. ....

Right. But how about the "targets" (the entire iron field) being "balanced out" ? Mind you, we're not talking "ceasing to hear any signal" ALTOGETHER. We're only talking about the "muffling affect". Ie.: "dumbing down"

 

[Old Longhair]

Now I'm confused as to what you're driving at. Not that it would necessarily, but let's say that the trash gets balanced out.... what's the problem? As long as the machine still recognizes the high conductor amidst the iron, haven't you achieved the basic objective of GB?
A couple of other things to consider when talking about Xterras. One would be the fact that it "balances" by means of Phase Angle shifts, not by applying filters as other machines do. Another is that the Xterras are also all digital, so most of what it does is controlled by programming and isn't subject to variations the way that analog machines are. In these respects they are unique.

 

[Tom_in_CA]

.... but let's say that the trash gets balanced out.... what's the problem? As long as the machine still recognizes the high conductor amidst the iron, haven't you achieved the basic objective of GB? .....

Well, yes and no. "Yes" in that you are now "balanced", as you say. Albeit balanced to THE IRON, versus the ground. And mind you: the spread of iron, is never truly 100% constant, right ? Eg.: there could be 5 nails under your coil here, 3 there, etc... Right ?

But no in that you're not truly accurately ground balanced at any moment of time. Hence loosing depth on targets.

Mind you it's only subtle. Because honestly, even an incorrectly ground balanced machine will still get signals, of course. But as you know, sometimes "subtle" can be the difference between hearing a target, or missing it An example of this is another machine is the 6000 di pro: Guys working ghost towns type nail riddled places, would turn off their auto-track, and go manual, for this very reason.

....A couple of other things to consider when talking about Xterras. One would be the fact that it "balances" by means of Phase Angle shifts, not by applying filters as other machines do.....

I have no idea what you're talking about.

 

[Old Longhair]

To explain things a little, I offer these links to read.
http://www.findmall.com/read.php?55,1783221,1784204#msg-1784204
http://www.findmall.com/read.php?55,1578540,1578644#msg-1578644

BarnacleBill has even outlined a method of measuring both magnetic and conductive mineral levels that you might find useful.
http://www.findmall.com/read.php?55,574329,574329#msg-574329

And I would also suggest that you read Randy's e-Book, paying particular attention to the Q & A with Dr. Laurence (inventor of V-Flex technology), as it addresses several aspects of this discussion to some degree.