MAG Building Poll

[Willy Bayot]

See also the post of a satisfied user here:
http://www.geotech1.com/forums/showthread.php?t=14845

[Willy Bayot]

Hi all,
There were a number of very successful site tests made with known targets buried at known depths by some of our first users. Our system was put in competition with various electro-magnetic systems (FDEM and TDEM) and its performance was unequalled to precisely locate deeply buried iron objects.
If you did not yet go there, have a look at http://www.ppm-markii.net/index.htm
There, you will find all about the specs, price structure and benchmark test results.
We currently are in the process of producing a second production series of our system as the first one was exhausted.
This process is expected to take about three months before delivering the first instrument of the new generation.
However, we already accept to take some order reservations for that series (and we already have got six reservations for the new series).
We normally prefer to sell the 'KIT' (as described on our web site) but we also can make the effort to assemble some 'SEMI-KIT' where the only work left to be done is some mechanical assembly and packaging.
The 'KIT' contains all the necessary assembled and tested modules (electronic boards + sensor coils) and can be provided with all the mechanical components necessary to package the control system into a proper NEMA box.
In both cases, the sensor coils have to be inserted into a suitable non-magnetic container for their mechanical protection and a 12V battery has to be provided by the client.
For all these, there is no need of any knowledge of electronics, just the standard level of DIY for mechanical assembly. Each set of boards is fully site tested with its sensor coils before being delivered.

Willy

[rgecy]

Willy,

Just wanted to check on the progress. Any new news? Things have been kind of quiet around here.

[Willy Bayot]

Magnetic Survey interpretation

Hello Willy ,
Thank you for your explanation ...see the Photo, do you think I am right in understanding the data o explain us a little more to definitely have a good perception of the target and very sorry for my ignorance of magnetometry...thank you again for your effort and your equipment conception.
Best regards.
Alexis

This is my interpretation of the plot. Note that the leftmost target could be a monopole or a small dipole and the one I noted as a dipole in the middle of the plot is questionable.

Willy

[Alexismex]

It?s ok

Hello Willy ,
Thank you for your explanation ...see the Photo, do you think I am right in understanding the data o explain us a little more to definitely have a good perception of the target and very sorry for my ignorance of magnetometry...thank you again for your effort and your equipment conception.
Best regards.
Alexis

[Willy Bayot]

Magnetic Survey interpretation

Hi all,

If you want to fully understand the theory behind the magnetic survey interpretation rules, you should read the following document: http://perso.infonie.be/j.g.delannoy/BAT/ampm-opt.pdf in the chapter V Interpretation.

The effects of the presence of an object made of magnetic material upon the local earth magnetic field is ruled by well-known physical laws and are independent from the type of magnetometer instrument used to make the surveys. Every such objects act much like a magnet with two poles (dipole) where one pole re-inforces the total earth field and the other pole decreases it (e.g. a cannon made of iron). Sometimes, a dipole has its two poles so much distant from each other that the survey instrument just measures the effect of the closer pole, this is then called a 'monopole'. This is the case if a long object is buried vertically. In that case, the instrument will only see the effects of the top end. This is also the case if the object is round (e.g. a cannon ball)

To make things simpler, there are thus two main cases to consider:
1. A monopole signature will show as a single point on the plot with a large positive field gradient (a mountain). In that case, the object is located right at the top of the positive peak. See test2, this is a ball-shaped object made of the accumulation of magnetic coins. It is located at around 4,3.
2. More usually, you will see dipole signatures where you see a positive field gradient (a mountain) close to a negative field gradient (a valley). This is the effects of re-inforcement and weakening of the total earth field at the two ends of the dipole. You draw a straight line between the two peaks and the object is located just in between with its orientation given by the straight line. This is the case for all the other tests.

The depth of an object can be evaluated by the sharpness of the peaks. Shallow objects generate sharp peaks while deep objects generate low and wide peaks.
The test 4 shows two simple objects of different weight and buried at two different depths in two different orientations. The bigger one generates a large field gradient of around 45 nT (this is the difference bewteen the total field at the positive peak and the total field at the negative peak).
All the color changes shown along the borders of the surveys have to be ignored, they are meaurement and gridding artifacts.
If the survey area would have been much larger, these peaks would show like montains in the middle of a flat desert.
In test3, the ammo box was explicitely buried at the location shown on the 2D plot and showed a signature of a typical dipole but it seems that there was already a target of unkown nature in the survey area. An actual digging could uncover this 'mystery'!

Coming now to the test1, this was the most delicate case of all as the targets are magnetically small and buried deep (almost 3 meters).
The only target parts that can ever be detected by a magnetometer are the iron sheets making the ammo boxes. It is obvious that the copper content and the coppe sheet are invisible to its 'eyes'. They were put there as tests for TDEM and FDEM instruments.
Since they are clustered, their individual dipole signatures combine together and the interpretation of the precise shape and orientation of those three distinct targets is impossible.
There are two other effects which disturb the interpretation of that particular plot:
1. You can see the waves on the 3D plot between successive survey lines. This is the effect of a small magnetic object carried by accident on the operator body or in the control box. This survey was still made with the sensor carried at the back of the operator and that made it too close to the box. In the meantime, this has been corrected by a different sensor carrying configuration.
2. On the 2D plot, you can see a stagging of consecutive survey lines. This was due to a bad synchronization of the start and end reading points on the zig-zag survey lines. The operator has now corrected this end/start survey line operating procedure.

In spite of these disturbances, the combined dipole target is visible. Again, the border lines have to be ignored.
This test will be re-executed and its results will be published again to clarify this case.

A few more comments:
To Carthage,

Looking for gold with a magnetometer will not really be directly detecting it. The only good reason why one would use a mag to look for gold is that it would easily detect 'black sand' and iron ore deposits which are usually co-located with gold ore. But it would be completely useless if you look for gold nuggets in river beds.
Also, the real shape of targets will NEVER be shown by ANY magnetic or electromagnetic instrument. It will always show rounded corner signatures.

To Alexis,

I can assure you that the test field is generally clean from any foreign magnetic material but, if a dipole signature is shown, it will ALWAYS be the indication of a real target and not random noise. Our instrument gives with each of its readings some quality factors which guarantee the validity or invalidity of a field reading. This particular test site is very far from any source of electromagnetic noise and all its readings were verified to be correct. This means that enlarging the survey area would not show many other '35X20 targets???' as you suggested. If there is nothing buried, the plot will be 'flat' all over the area where there is nothing buried with magnetic material. I have already published on this forum some larger survey area I made over our archaeological site with a few potential targets shown as dipoles. At that time, I was still using a previous prototype version of the our mag. Look at the post dated 05-31-2008, 08:38 AM in this thread.
I also have complemented the test report with a larger survey area showing a few examples of dipoles and monopoles.
The survey area of these tests was strictly limited to the interesting spot in order to limit the time and effort consumed for the tests.


I hope this will slightly clarify my points.

Willy

[carthage]

Hi all,
We have got independent benchmark test results from one of our first users.Those results are much better than we could have ever dreamed of. They are at least equivalent (if not better) to the results you get from a 'professional' system but at a quarter of the usual commercial pricing.,

Look at our web site, you'll find the full story.
http://users.skynet.be/fa352591/
Willy

Hi Willy,
I am really interested to get one of your gadget but the bench mark to me is not clear and very confusing. too too many red targets showing in your data and and very confusing for a treasure hunter. it looks like targets are every where down there, and for somebody how is looking for gold would not know where to begin digging.
Is it possible to show the target shape as clear as possible? or some how make a little bit of distinction the showing targets.
Willy, I am not criticizing or questioning your very good work here, but for me I need to make sure to understand what I will get for my team.
Best regards,

[Alexismex]

Hello Willy ,
here we are interested for your equipment but the test result are not well explain and very confusing ( for me)!!!! Take for example the test 3 the amno box : you are pointing a arrow to a orange rectangle between blue and red variation not in the center of the blue ??? or in the center of the red??? ....the same for a unknown target

For the test 4 the same i do not see the arrow in the center of the red white o perhaps i do not understand the concept between positif and negatif and for the sheet of 35X 20 it is between green and blue and i suppose if the photo will be very large i will see many of this plate of 35 X 20 ???? (if difficult to me to explain in English ).

For the test one i do not see nothing of the good preparation i see in the photos , please make comments.... explanation with PRECISE ARROW on your photo to explain where YOU SEE EXACTLY THE TARGET...

I see you make many effort to realize your detector and see you make a very good work Willy but it is very important for me and the forum to understand well the test data with your comments ... and also important to make the decision to buy your Kits.
Have goods days and Regards
alexis.

[Willy Bayot]

Benchmark test results from the PPM MarkII system

Hi all,
We have got independent benchmark test results from one of our first users.Those results are much better than we could have ever dreamed of. They are at least equivalent (if not better) to the results you get from a 'professional' system but at a quarter of the usual commercial pricing.,

Look at our web site, you'll find the full story.
http://users.skynet.be/fa352591/
Willy

[Willy Bayot]

Hi all,
I have updated the web site with pictures of our first unit in its final production packaging. See http://www.ppm-markii.net

Willy

[Willy Bayot]

Hi all,

This is finally our best proposal for a PPM Semi-Kit package.
See the new thread in magnetometer chapter.
We are waiting for your reactions and questions.

Willy

How much $$$$ ??????

[Baran]

Magnetometer

Hi willy,

If it isn't still too late, I am interested as well.

Thanks

Willy,

We still need your kind of diff mag as I think it will cost less than having to buy from commercial.

The flux mag does not meet our requirements as it's sensitivity is shallow.

Please inform us when you're done and ready to sell your mag.

Anyway, thanks for the email add. I will write you later.

Junkie

[Willy Bayot]

Hi,

I am surprised that you could not register to the forum. You should be.

The estimate we gave before was for a kit made of a set of boards, not for a full PPM system with its box, stick and sensor.
Indeed, to get a differential PPM system, you need two separate instruments, one acting as fixed station and the other as mobile station.
However, it depends what you are searching for. If what you look for is made of magnetic material like magnetite, iron or steel, the field gradient generated by those will very much override the daily field variations and you should not need a differential instrument in that case.
For archaeological surveys looking for weak gradients generated by underground structures like wall foundations, fire pits or wells, this is indeed necessary.

My email is :[email protected]

Regards,
Willy