Jeohunter - Visual Ground Scanner

[Qiaozhi]

So I wonder if it would be possible to built an improved PI that
works with DD coil?

PI detectors can already work with DD coils. They have the advantage of better pinpointing, but the mono coil tends to have greater depth.

[Funfinder]

Yeah, would be very interresting how the Jeohunter compares in Australia.
If there is a massive wall of steel every MD would fail to see whats behind.
So it depends how strong and mixed mineralic the area is and that the
coils size matches the targets.

If it is very important for very deep finds that the detector has a very good
signal noise ratio of course this is especially no easy task with huge coil
if the ground consists of "varying detectable stuff" itself.

But to make the ground "blurred" by motion circuits has the same result
like lowering the sensitivity of a detector. And here we enter the world
of subjective tastes. Some like just digital beeps and other like to hear
the background "snap crackle and pops". Some find automatical motion
ground layer compensation very useful and other prefer to press a reset
button if there are heavy mineralic changes in soil.

If PI really would penetrate the ground that easily, it would have much
better depth compared to the Jeohunter but this isn't the case because
the PI coils are not that complex and the eddy current echo detection
is an area where alot of errors can occure like overdriving and timing.

However - I'm interrested in all good detectors - I'm not fixed to the
Jeohunter - it's just a super depth detector that can find little stuff
also and cavity and can recover very fast because of the large coil -
but I am absolutly interrested in any good working detectors from
the electronical / technical point of view.


So I wonder if it would be possible to built an improved PI that
works with DD coil? Eventually the coils would change in activity -
this could double the sometimes very low recovery speed and it
could lead to better ground elimination, too. And how far are the
actual efforts getting disc. for PI without magnetometer-support?

Because what counts overall is the whole package. Hunting for
very small gold nuggets in an area without other metal is great
with a MD that is specialized for the high mineralisation and uses
a pretty small coil but it's no more big fun on a trashy beach.

Finding out how sensitive and deep a detector really works is
pretty simple by using very large coil and small buried object...

[Qiaozhi]

However heavy mineralized ground of course changes the reflected eddy currents what can became a big problem for PI.

Heavily mineralised ground is a big problem for all types of metal detector. The situation is even worse when the level of mineralisation changes rapidly over a short distance. This is why VLF detectors, and particularly non-motion based detectors, perform poorly in these situations. In your case, where you are primarily using a large coil frame, these ground effect problems tend to be masked somewhat, as your coil is far from the ground and you are searching for large targets. If you were to test the Jeohunter in Australia, I suspect it would fail to perform to your expectations.

[Funfinder]

Thanx for the detailed explanation how PI handles ground.
And finally we're ontopic again.

However heavy mineralized ground of course changes the reflected eddy currents what can became a big problem for PI. From my test experiences the Jeohunter can measure the mineralic strenght itself, too, that's why it even can distinguish different mineralised stones or meteorites and cavity.

Besides those powerful PIs that can handle 1m or 50cm coil have lower depths than the Jeohunter. Carl also tried a PI at his cache test and the signal was very weak in air and not detectable with buried coins.

And if nonmotion VLF really is "worst" then that's a question how the motion is calibrated and of personal taste. Those electronical motion filters can delete alot sensitivity especially for huge metal objects.

The Nokta Golden King is almost the same so you can get some picture. "Bulky" is no argument because a huge coil always is bulky. A PI with 1m frame's much more bulky.

Your PI arguments are fine but what really counts are tests under real conditions. So I suggest if possible we should compare the Jeohunter with the depth of the Minelab GPX 5000 using a large coil or with a 30V -> 1kV 4th generation PI system that costs around 4000 Euro in Germany. Bulgarian Deeptech PI also claim to have very good depths but without tests they can tell everything. The 50cm frame at least looks more like some diy plumber work and I don't know if it really detects a softdrink drink-can at 1m / 3feets.
Perhaps this will work at static in air tests with fixed coil only, otherwise a 1kg coin cache also could be detectable at this depth. If you have a PI with 50cm coil you could make some tests so we see how it compares.

For further information here's the new pdf manual for the Jeohunter 3D Gold:

http://www.multiupload.com/FZ4D2I1SIR

[Qiaozhi]

Monocoil PIs have not real "ground balance", they have "mineralisation detection timing". Balance (in french the name for a scale is balance and in spain balanza) has to do with 2 different coils that are able to recognise the feedback of the coils inductivity while interacting with the huge ground mass. [..... etc., etc.]

Yes geohunter manual ground balance is very very better than pi.if you can worck by geohunter you understand .and i can balance geohunter in the very bad ground in 2 minute .and when your detector un balance you can Easily reset so balance your device the mineral effect in vlf detector is very lowand you can easily balance your detector

I get the distinct impression from your posts that neither of you understand how a PI functions.

Unless you have a PI with a very short sampling delay, it will not be affected by ground mineralisation. Therefore, there is no requirement for ground balancing. In particular, for the mono coil, the term "balance" makes no sense. The Geohunter (and for that matter, any VLF detector) needs to be ground balanced, even for non-mineralised soil. Balancing relies on the fact that the received signal from the ground matrix contains only amplitude changes, and no phase shift. The method of ground balancing aligns the sample pulse of the synchronous demodulator with the received signal, such that amplitude changes are effectively ignored. Hence any signal from the ground is also ignored. For a PI, this is simply not a requirement. The PI relies on the fact that the ground matrix is unable to sustain eddy currents for any significant length of time, whereas wanted [interesting] targets can maintain the eddy currents for much longer. Therefore, sampling after the ground signal has disappeared, but before the target signal has decayed significantly, means that PIs have a much better tolerance to bad ground than any standard VLF could ever hope to achieve. Multi-frequency detectors (such as BBS and FBS) use different techniques to eliminate ground response, and also provide better results than a standard VLF. Non-motion detectors are the worst, as far as ground elimination is concerned, mainly because the user must maintain a constant distance between the bottom of the search coil and the ground.

I do not know the Geohunter, so am unable to comment on it from first-hand experience. Although I have seen a Nokta Golden King in operation, which I understand is very similar. It was expensive, large, bulky, difficult to use, and the LCD screen was unreadable in bright sunlight. The user of the Nokta had owned the detector for over one year, and had found a Saxon grave in a location where he knew a grave could possibly exist. Apart from that, he seemed to have found little else. I was not overly impressed by the so-called 3D imagery. In tests, that we carried out, the image did not resemble the buried target, and it was difficult to understand what we were actually seeing on the screen. It also detected lots of cavities, which were actually non-existent.

Obviously, a PI has the disadvantage of not having an effective system of discrimination between ferrous and non-ferrous targets, but has major advantages in the areas of depth, the ability to ignore mineralised ground, and to work in wet sand on the beach. Of course, the "holy grail" would be a PI detector that could do all this, with effective discrimination.

[ishtar hunter]

Please explain how the Jeohunter (which is essentially just a VLF detector) can have much better ground balancing than a PI?

Yes geohunter manual ground balance is very very better than pi.if you can worck by geohunter you understand .and i can balance geohunter in the very bad ground in 2 minute .and when your detector un balance you can Easily reset so balance your device the mineral effect in vlf detector is very lowand you can easily balance your detector

[Funfinder]

Please explain how the Jeohunter (which is essentially just a VLF detector) can have much better ground balancing than a PI?

Monocoil PIs have not real "ground balance", they have "mineralisation detection timing". Balance (in french the name for a scale is balance and in spain balanza) has to do with 2 different coils that are able to recognise the feedback of the coils inductivity while interacting with the huge ground mass.

However what finally counts is how good the detector works under real conditions, in this case very high mineralic circumstances and PIs, have, compared to "steady transmit receive coil antennas" the problem that, the echo-pulses can vary extremly on "bad ground". And the internal electronic measure circuit, too.

Make your own tests with a non-motion induction balance detector against a PI with same coilsize and put some metal objects below a wide layer of hot-rocks.

Technically spoken even mineralic ground has it's own discrimination value. Like with metal the electromagnetical flow can be measured. So how should a PI can measure this if it even can't discriminate noble metal from rusty iron? So first the PI must have special wave-form recognition and adjustable timing circuit to get the needed info out of the feedback-pulses. The usual ground balance of PI is just some timing-trimmer that may work very well on good known and for large areas not changing grounds like black sand. If you have areas with big highly mineralized stones here and there under notmineralic soil and fast varying conditions the PI may see these irritating factors as metal objects...

Like with VLF there also exists PIs that can handle very "bad" ground better or not so good. The Jeohunter can look through highly mineralized ground as my axe below over 1feet / 40cm bricks find has shown already. I hope some of your PIs can do the same and can really distinct if it is metal or mineralized stuff below the surface. And it's the logical consequence for any detectors that cut out the whole "cavity and mineralization area" that those can get problems if the ground is "special". And besides so far no one ever heard about a PI that was able to detect cavity. But you may have some good insider news.

[Funfinder]

@WM6

Poems are nice for dreaming, books, theaters, lyrics and songs but not useful for real conversation.

There is too much room for subjective interpretation and camouflaging what should be better said clearly. And some authors only writing in rhymes or riddles because they think this would make their useless thoughts more important. Often they're just fooling others.

If your "M6 is god" is just and ironical statement that shall tell us that metal-detectors are "pointless" as you think the Jeohunter is, I wonder what really counts for you and what is your "mission" in this forum?

Metal detectors are tools for finding lost things and mementos, cleaning landsites from war-remainings, finding interresting stuff and ground-treasures and fit to the need of mankind discovering the unknown. So what's your problem with a detector like the Jeohunter that makes a very good job at all those topics?

And if you wanna tell / ask me something special with your 2 poems, say it for everyone understandable, because otherwise such activity just leads to misunderstandings!

btw. Goethe really made one of his journey through my little home town - perpaps i find something from him.


And you, WM6, if you would have no access to any metal detector and lost something very important out of metal, as example in high grass where you can't find it anymore, would be very very glad and thankful if someone with a Jeohunter would help you getting it back!

So be careful of what you're doing and writing here, it could bounce back on you very hard sometimes!

[joejoe]

When I first joined, I never thought I'd be reading poetry in it's original language. Talk about a high-brow metal detecting forum!

[Qiaozhi]

[Comparing the Jeohunter to a PI] ... and has much better ground balancing.

Please explain how the Jeohunter (which is essentially just a VLF detector) can have much better ground balancing than a PI?

[WM6]

WM6, you may become a new Goethe or Shakespeare.

Become?
I love to, but I know that I cannot owercome
such timeless geniuos as Shakespeare (read this and try to understand):

Sonnet 66

Tired with all these for restful death I cry

Tired with all these, for restful death I cry,
As, to behold desert a beggar born,
And needy nothing trimm'd in jollity,
And purest faith unhappily forsworn,
And guilded honour shamefully misplaced,
And maiden virtue rudely strumpeted,
And right perfection wrongfully disgraced,
And strength by limping sway disabled,
And art made tongue-tied by authority,
And folly doctor-like controlling skill,
And simple truth miscall'd simplicity,
And captive good attending captain ill:
Tired with all these, from these would I be gone,
Save that, to die, I leave my love alone.

Und great J.W. Goethe tut auch nicht so schlect:

Generalbeichte

Lasst heut im edlen Kreis
Meine Warnung gelten!
Nehmt die ernste Stimmung wahr,
Denn sie kommt so selten!
Manches habt ihr vorgenommen,
Manches ist Euch schlecht bekommen,
Und ich muss Euch schelten.

Reue soll man doch einmal
In der Welt empfinden!
So bekennt, vertraut und fromm,
Eure größten Sünden!
Aus des Irrtums falschen Weiten
Sammelt Euch und sucht bei Zeiten
Euch zurecht zu finden!

Ja, wir haben, sei's bekannt,
Wachend oft geträumt,
Nicht geleert das frische Glas,
Wenn der Wein geschäumt;
Manche rasche Schäferstunde,
Flücht'gen Kuss vom lieben Munde
Haben wir versäumt.

Still und maulfaul saßen wir,
Wenn Philister schwätzten,
Über göttlichen Gesang
Ihr Geklatsche schätzten,
Wegen glücklicher Momente;
Deren man sich rühmen könnte,
Uns zur Rede setzten.

Willst Du Absolution
Deinen Treuen geben,
Wollen wir nach Deinem Wink
Unablässlich streben,
Uns vom Halben zu entwöhnen
Und im Ganzen, Guten, Schönen
Resolut zu leben;

Den Philistern allzumal
Wohlgemut zu schnippen,
Jenen Perlenschaum des Weins
Nicht nur flach zu nippen,
Nicht zu liebeln leis mit Augen,
Sondern fest uns anzusaugen
An geliebte Lippen.

After all this, how can you advocate such pointless things as jeohunter? How?

[Funfinder]

good - god, evil - devil...

Here we have the most wrongest german loan words used in english rhymes!
Because the spelling sounds so identical and suggest the attributes are true.

WM6, you may become a new Goethe or Shakespeare.
But better stop such rhymes. It may be ok, if you start
some "spiritual wakeup call" with your signature but the
"good - god" combination is the wrongest way you can go.

1. If god would be good n almighty noone ever would suffer. Just look at Africa.
2. Your funny claim 'M6 is god' is satanic like the dance around the golden calf.
3. Choosing such middle class detector as "god" undermines your respect here.
4. The supposed god of one religion / culture often is the satan of some other.
5. You may defend your signature but in reality it's just "stealthy advertising".


And I can hardly believe that you are taking the opinion of a detector-dealer
as granted concerning the Jeohunter. Because you should know it much better.
Don't you think that metal-detector resellers may have their own reasons to tell
others why they should buy them or not? I also know such dealers - their opinion
is that the Jeohunter just is an overpriced VLF detector and it's bad for little stuff.
But those misjudge the big pros concerning fast area search and high depth power.
I am "brute force hacking" whole square-miles / kilometers and this is just possible
with devices like the Jeohunter or others that can handle over-dimensional big coils.

And believe me, the Jeohunter will find much better coins compared to a PI with
such a big coil. And it will find cavity too and has much better ground balancing.
If the Jeohunter detects very deep metal at very high mineralized ground, then
there really is metal and you don't waste your time by diggin' very deep holes
for nothing like it can happen with PI that start to siren at almost everything.

And besides this: "that dealer told me the Jeohunter doesn't work for small
goldcoins" is absolutly no excuse for what you've done already, on and on!

You are acting like a poltergeist against the Jeohunter for your own fun!

Perhaps it brings some social interaction input so it's not just dry electronic
but also the mood and emotions of the users what you wanna provocate here.
But beside this is really terrible, offtopic, unscientific, defamatory and irritating.

[WM6]

WM6 adds an unnecessary information:
Most MD are good, but M6 is God

Unnecessary? People today are so listless, depressed and alienated that tey need something to irritate, excite and awake them. As last help God is comming here in the image of Whites M6, and, as we can see, effective.

[der_fisherman]

Turkey and its people.....

I am quite impressed with the metal detecting fraternity from Turkey, both here on Geotech and in the country itself, its also one of my favorite holiday countries as well.

My father was sent there in late 1940 to help the Turkish army and airforce, to make them good enough to take part in World War 2, but they were so traumatized from the First World War (picked the wrong side), they never did actually join, but he had a great 4.5 years among them. All thanks to Churchill!!

He still spoke fluent Turkish till he died in 1978, either helping Turkish lorry drivers caught by the police in the UK, or ordering food in Turkish restaurants! That's all we ever had when I was small......I knew Turkish food better than English till I was 10 or 12!!!

He really loved the people and the country itself!!! So does my wife, Family and I.....

Regards

Andy

PS. Sorry, this has little to do with metal detecting, apologies to all.......

[mikebg]

Thank's for your translate.most metal detector turkey are good .(dedektörleri) Purpose:turkish detector.

Ishtar, my joke was addressed to WM6, but not to Turkish designers of metal detectors. On every his post in the forum, WM6 adds an unnecessary information:
Most MD are good, but M6 is God
Thanks to WM6, soon Turkish designers will create a metal detector capable of problemloss operating in very bad ground, because he said here in the forum where in Turkey there is the worst ground.