Ivconic Magnetometer/Gradiometer

[ionut_mtb]

I am passionate ancient Roman coins hunter, for over the 30 years.
Most of the sites where i usually do hunt are plowed fields.
After 15-20 centuries of plowing and manuring the same soil; various chemical processes are occurring there.
Most of the coins situated in such soil are totally covered with oxides and calcite.
Actually; the main problem at collectors is the process of removing such layers and cleaning the coin without damaging it.
Conventional VLF I/B detectors are struggling to properly discriminate because of the oxide layers and calcite on such finds.
So many times i dug nice silver or gold coin with totally spurious and doubtful signal at my detector.
VDI numbers going crazy and mostly false at such cases. Audio is crackling and mostly indicating "bad iron" or so.
It is only the rich experience that makes the difference at such cases.
Obviously those are pretty "magnetic" situations, where magnetometer can do the job just fine.
It would be crazy to search with it for single coin, yet it is very effective if you search for coin deposits, lot of "magnetism" there.
Plowed fields, arable lands... usually are (and were back than) at low altitudes, along the river banks.
Meaning further that during the centuries river flooded many times, bringing more material, mud and finally risen the level on such soils.
Meaning further that many ancient settlements are completely buried in soil. In many cases well preserved and "conserved".
The most important factor and indicator in such cases is pottery, clay and ceramics.
If you discover clay&ceramics formations - you discovered all. You got a bingo!
Now this opens another hell interesting story; the clay baking process at ancient times.
How is done. What are the most interesting aspects of it. Chemical and thermal processes (Curie point and relation with Earth magnetic field, clay "memory" etc).
Hell of a story!
But it is redundant me to write novels here. There are books and books.
Just read!

True story! what you said here takes years for people to understand. most of the buried coins pot will give a bad signal, due to clay/ceramic composition of the pot, the stone on top of it, or the corrosion/material of the coins. i don't like to say it but i can't trust anymore vlf detectors, not for the ex settlements... and even if the soil is good, the depth is so limited...

[MTammet]

Whole project is on sale now.
Bunch of cheap yoyos tried to make with me sort of "partnership" so far.
Obviously expecting to get something for nothing, from me.
Not gonna happen.
So... whole project is finished, tested and on sale from now on.
Make no mistake to hope for a free lunch from me here.
Those times has passed long time ago.
Money in advance would be your only ticket for this boat.
As far as i am concerned; this topic is closed now.
Enjoy!
Cheers!
P.S.
Interested can contact me via email.

Sent you a private message.

Best Regards,

Mihkel

[ivconic]

Fun:

[homefire]

Dang ,, Good Video.

[pigeon]

[QUOTE = ivconic; 252672] Fun:

[vidéo = youtube; Of-_BBHYwRE] https://www.youtube.com/watch?v=Of-_BBHYwRE [/ video] [/ QUOTE]


THANK YOU VERY MUCH

[ivconic]

Fun it is, but also truth.
I've been working on magnetometer/gradiometer project for quite a while.
Initial design is finished recently, as i posted.
But now is time to make it more complex and more serious... hopefully.
I plan to implement series of digital filters in code.
But first i must learn much better on Earth magnetic field and all its features.
So "studying" over the net; every once in a while i stumble across something interesting and fun.
Most important; highly educational!

[EL NINO]

[QUOTE = ivconic; 252672] Fun:

[vidéo = youtube; Of-_BBHYwRE] https://www.youtube.com/watch?v=Of-_BBHYwRE [/ video] [/ QUOTE]


THANK YOU VERY MUCH

... Yes ... That's really good ...
...

[homefire]

More Crazy Magnetic Stuff : https://www.youtube.com/watch?v=OI_HFnNTfyU

[ivconic]

[homefire]

Wish I could afford a 3D Printer. Maybe some day.

[ivconic]

Wish I could afford a 3D Printer. Maybe some day.

Ender3 is affordable.

[ivconic]

3d printed insets for sensors, to perfectly fit into pipe later:





"Cross" on the bottom is for plastic screwdriver, for later fine adjustments.
"Channel" on the side is for placing the cable from bottom sensor, passing bellow the top sensor, up to the top of the pipe.

[ivconic]

To avoid ringing; high quality coaxial leads are MUST.
Along with low pass filter at the end. Cut off at 80-100kHz preferably.
There is also another HUGE "meister" secret... which i tend to disclose here...
Will i? Or will i not? To bee or not to bumblebee... it is the question now?
Copper pipe!

Natural "filter" which additionally (positively) affects the ... i shall stop now, this is enough from me.
I am not payed enough for this!
N'joy!

[MTammet]

These amplifier were once extremely expensive. https://www.ebay.com/itm/Lock-in-Amp...-/282771110382 If you use your upper sensor as reference signal you can probably get good accuracy when measured. You can adjust filters on that board.

[ivconic]

These amplifier were once extremely expensive. https://www.ebay.com/itm/Lock-in-Amp...-/282771110382 If you use your upper sensor as reference signal you can probably get good accuracy when measured. You can adjust filters on that board.

Cool!
After we exchanged emails; i was seriously buried into such problematic.
Your suggestions are making lot of sense to me.
Therefore i do seriously intend to deal with that in nearest possible future.
It is not the price the deciding factor. It is the gabarite and setup of such and similar modules.
I was rather thinking on designing my own lock-in amplifier.
Current version of code is having simpler running average filter.
Quite subject to improve in next updates.
What to say?
Big THANKS for pretty constructive suggestions!
Cheers!