from M.D to imaging

[AK48]

good evening and thank you for the diagram, it became serious, no problem for the codes my first goal is to understand where the data are taken and where are they injected, so I will try to understand this diagram meticulously, thank you again and good luck
NB/ you said : " The "pitch" (frequency) of the PSII audio is precisely measuring and logged constantly.
Than from internal buffer taken and sent by BT to Android " and this is the part that interests me the most, from what I understand, the data is sent via BT on the software, this software must be designed and dedicated I think? Isn't it possible to integrate this BT data on commercial software? I'm thinking of the Visualizer3D "hey, I like the colors

[AK48]

sorry , question

[ivconic]

good evening and thank you for the diagram, it became serious, no problem for the codes my first goal is to understand where the data are taken and where are they injected, so I will try to understand this diagram meticulously, thank you again and good luck
NB/ you said : " The "pitch" (frequency) of the PSII audio is precisely measuring and logged constantly.
Than from internal buffer taken and sent by BT to Android " and this is the part that interests me the most, from what I understand, the data is sent via BT on the software, this software must be designed and dedicated I think? Isn't it possible to integrate this BT data on commercial software? I'm thinking of the Visualizer3D "hey, I like the colors

I don't know proper answer on that.
I made my project from a start on my own.
So i decided what will go where and what will do what.
Trust me on this; it is always the best way to make things completelly from a start on your own.
Than you are "master" of it, you understand it all.
...
Arduino UNO is based on Atmega 328P. So by the time i was able to make own projects; i had to pass certain learning curve and to read and try a lot.
HC05 (later HC06) is ready BT module. So i made many simple things by hooking up HC05 on Arduino Uno and experimenting only with that.
Same goes with SD card reader module. Same goes with many LCD&GLCD&TFT&OLED display modules.
12-14 years before that i made Becker's EPE magnetometry logger, probably dozen diys, with few of those i gained good field experience.
So... as you see, there is certain history behind anything i did. So as well behind anything everybody else did and do.
My software (my son's actually) is especially designed and dedicated for this task. Not only to perform calculations and aglorithms for 2D/3D imaging, but also it includes the connection with outer world (COM ports under the Windows, BT etc)
Is it possible to integrate the same in some other software, like Visualizer 3D?
I think it is possible and probably easy task... but only for one who is having source code for that software... aka the genuine author.
That's why is better to give it up and make it on your own, from a start.
Easier said than done... yes that's true.
But not impossible.

[ivconic]

sorry , question

[ATTACH]57189[/ATTACH]

Not relevant for this topic so there is no label on it.
It is a counter.

[Krzysztof]

It is a type 4040 integrated binary counter used here as a frequency divider (in this connection it divides by 32).
Because the processor measures the frequency at the D3 input, it uses the INT0 hardware interrupt. To maintain the continuity of the program's operation, the signal from FGM3 is divided by 32.
With a signal from the sensor in the range of 40 - 120 KHz, the processor would hang itself - in addition to measuring the frequency, the program does other burdensome things.

[ivconic]

It is a type 4040 integrated binary counter used here as a frequency divider (in this connection it divides by 32).
Because the processor measures the frequency at the D3 input, it uses the INT0 hardware interrupt. To maintain the continuity of the program's operation, the signal from FGM3 is divided by 32.
With a signal from the sensor in the range of 40 - 120 KHz, the processor would hang itself - in addition to measuring the frequency, the program does other burdensome things.

Not only hangs, but chokes totally, when reaches 62xxx samples!
It was funny at the first attempt to see how it slows down and completelly chokes, i had LCD attached with some simple numbers rolling.
And that's only for one sensor.
And in Euomag 3D there are two sensors, twice the trouble.
So i had to make a compromise.
But later in real work it shows quite good and acceptable results, for the purpose of amateur "archeology"...
Better than expected actually.
Use of mcu with more muscles will eliminate need for down sampling.
But than... FGM features are not that good for higher resolution measurements.
So... everything fell into place like slapping a fool!

[ivconic]

Willy Bayot much later pointed me on really sweet method of using the 16-bit timer.
So actually it is doable with Atmega 328P without down sampling.
But i was already finished my device and first units hit the market.
And as i mentioned; FGM capabilities are not such as to motivate for further improvements, though they are more than good for our usual amateur needs.
In meantime i realized that Willy is one really angry old man, so i decided not to use anything that he gave me as solution for commercial purposes.
Lest anyone should misunderstand this; I give my sincere appreciation and respect for Wiliy and his good will to help!
I learned valuable things from him.
Cheers for Willy!

[Krzysztof]

I also tested it once, which is why I went the way of direct measurement in T1. Simons in the first version of the DIY gradiometer divides the signal by 4 and everything goes - only there the program is skeletal and completely unloaded. Now in the new version it works on ESP32 but I did not look at what method it measures.

[Krzysztof]

Unfortunately, I'm also an old man and reliable writing goes slower for me, in addition, I use a translator, which is why I have a slip with posting on the forum.
I didn't know that the type of counter was proprietary, but for someone who started with the SN7400, it's sometimes enough to look like an integrated circuit in the diagram to know what's going on.
And to think that a dozen or so years ago Gradiometer fit me in 2313 but counted upper and lower sensor one by one, and today's CPU 8 bit are still getting better.

[ivconic]

I also tested it once, which is why I went the way of direct measurement in T1. Simons in the first version of the DIY gradiometer divides the signal by 4 and everything goes - only there the program is skeletal and completely unloaded. Now in the new version it works on ESP32 but I did not look at what method it measures.

ESP32 is definitely having more muscles, no doubts about that.
Somehow i can't keep one for more experimenting.
I had few, made a "product" from them and sold away.
These days is bit harder to buy them locally and the prices went high.
Obviously the crisis with the chips is real. And with the prices too.

[ivconic]

Unfortunately, I'm also an old man and reliable writing goes slower for me, in addition, I use a translator, which is why I have a slip with posting on the forum.
I didn't know that the type of counter was proprietary, but for someone who started with the SN7400, it's sometimes enough to look like an integrated circuit in the diagram to know what's going on.
And to think that a dozen or so years ago Gradiometer fit me in 2313 but counted upper and lower sensor one by one, and today's CPU 8 bit are still getting better.

First time i realized that those are having potential was when FelezJoo hits the forum.
I instantly made it and was amazed with fact how much juice was squeezed from a Atmega 328P!
It was clear to me that chip specs are not the limiting factor to me, but my ignorance!

[AK48]

good evening and thank you, with your comments I already know a lot more and I will start with the arduino which seems much simpler to me while keeping an eye on the more powerful and more complex DSPs

[Funfinder]

AK48, well well - imaging - there are different methods but the question is:

Do you wanna wrap a shiny "packet-paper" around the treasure-hunting itself so it looks more promising and lust-making or does it really helps?

Per instance I built an on-off-switch for the LCD-display into the Jeohunter and DeepHunter so the battery lasts the double amount of time and using the "visuals" for 95% was just a waste of time, anyway. Useful only for very deep and large finds where additional information makes sense. But those are rather rare. hahaha



Visuals depend on the amount of data - most simple method is to print or render a high resolution GPS-map on the screen and add a find-marking there each time the coil reacts strong enough.

Second method is like filming with a digital camcorder and save this movie on SD-Card. overlayed with GPS grid etc and real-time 3D visuals on screen. Combined in realtime with different colors for the MD-signals, depth, noble non-noble etc.

Usually this just makes sense if you wanna see the ground-structures of a huge area but its no fun walking 1meter stripes back and forth.
Thats the method for larger drive-around-magnetometers and creating landscape-detection-maps out of it.

And finally there is the live-output on screen while holding the detector which are representing the 3D EM-field or soil-situation around you.
This also could be recorded together with real-view images and GPS-grid etc - but in this case the screen-output directly can be used as detection-signals, even without any audio. In this case the sensors or coils of course must directly create a visual live-image, representing the actual signal strenghts with different colors etc. It depends - best would be a real-time-overlay live-image so you can watch the screen with all the added special MD-signal-details while walking and not stumbling. Depends also on the kind of detector which is attached to it, if the visual output comes from special googles and if there are any hands free to hold this stuff.

Most simple solution: Hold your smartphone in the other hand while treasure-hunting and film everything while hunting! hahaha
Personally I don't do this - just a waste of time. But I take some pictures if the find is worth it, also from the GPS coordinates. That way I also can see later where exectly are the hotspots or "shooting-directions" hahaha of certain finds or enter them into digital and/or printed out location maps. That way you can work a little bit like a professional archaeologist, too.

And these visuals from many Ground-Penetration-Radar-screens should become forbidden, because they are just a huge bunch of totally misleading and worthless crap !!! Either you receive or can watch clearly understandable signals or you better receive no signals at all !!!

[AK48]

thank you friend for this precision, in fact, if I mentioned the system for a metal detector, my goal was essentially didactic, my real goal was the addition of imagery for: either a magnetometer or a resistivity meter DIY for locating voids or underground structures.

[Funfinder]

That is fine and you are welcome with such interesting topics which can help everyone to create better MDs.

Well, in your special area of interests you also could work with satellite-maps or infrared-images. Because the stone-ruins under ground often have a little bit colder temperature as the sand or soil around - which also still affects a little bit the surface above such structures.

But I would start it slowly with just 30x30 meter sites. To create some sort of electro-magnetical ground image first some ropes or plastic lines as markings are needed and next the signals of these 30 stripes which are each 30 meters long, have to be saved as continuing signal line or as single signal pictures - and afterwards combined together. Most simple method is using some MD with analag to digital converter and laptop with data logger. Perhaps you even can use the raw magnetometer output in combination with a cheap circuit. You even can record the output as audio-signal if this audio represents the detection-values inbetween 0 and 100%. Later you can create a 2 dimensional search-area picture from the audio if the timing and walking-speed values are known. But with a software even the microphone input of a smartphone could be used for this and the results, the signal-values, become directly inserted or added into a GPS-map. And most smartphones have inbuilt GPS anyway and maps are freely available - also for offroad-locations.

For deeper and interesting single finds the meanwhile available imaging is more than enough - it shows the approx object size, depth and what kind of metal it is. Also if there is a larger cavity - but to find such cavities the soil must be good enough mineralized.


If I would need a simple but working DIY-"sunken cities"-area imaging detector I would first look for a detector with 1m coil or magnetometer but with directly the actual signal strenght representing output! No beep-beeps but a constant signal which represents zero if there is no detection-signal up to full 100% output. Or an audio which goes from very low to very high frequency. And next either using this signal directly or after analog-to-digital converting, very fast a simple but effective map can be created out of these recorded signals.