Let's made a PC-base metal detector with usb interface !!!

[vistac2000]

Hi friends,
I almost new in http://thunting.com/geotech/forum, and see this site amazing and very interest about metal detectors,
at first I am sorry if my english is not very good ...

I wish with your helping, we can made a new PC-based metal detector with usb interface, this metal detector will can operate with pc or laptop very well and with some nice advantages, such as exact discrimination & even measure depth of target ! and others ...

for first step, I think we must build a usb interface(hardware) & write a program(software) to connect to it, and with this interface we produce a signal with desired frequency and delay and etc... and amplification it for
sending to Tx coil, and then get this signal from Rx coil and analyze them for our purpose...
I think these, can a good starting point to reach to our target... ok?

I hope you helping me and another members of this site for this ...
If i get any other information about this, will share with you ...

with best regards for all members of this site

[ms.nomi]

Hi.

look this: https://www.geotech1.com/thuntings/s...ghlight=laptop

But this idea - with soundcard (no USB)

Michal

P.S. Sorry my english

[gwzd]

Laptops are too heavy, a PDA would be better. It has USB output and fairly good processing power. It could be mounted on the handle of the metal detector and running a real time FFT analyzer and showing the frequency and phase changes. It shouldn't be hard to do it, the question is: who would pay for it?
best regards
RA

[vistac2000]

Hi,
Thanks for ms.nomi and gwzd ...
yes, PDA can be better in light weight, but did PDA cpu enough for this job?

also programming of pda is which language? what is usb interface for PDA?
if you have any idea please share it to use for our purpose...

anyway,for laptop i found a usb interface with PIC18F4550 to start:
i am waiting for any idea, thanks...

[ms.nomi]

https://www.geotech1.com/thuntings/a...1&d=1163435558

Use this circuit with A/D converter for signal from receive coil.

Output for TX coil can be controlled directly digital output


Michal

[Aziz]

Hi,

you should decide, which type of detector you want to develop.
1. PI
The AD converter of the mentioned PIC is very likely not fast enough for PI systems. PI systems need at least 1 MSPS (Mega samples per second, 1 µs resolution). Using Flash-A/D would be better but expensive.

2. VLF
For VLF you do not need such a PIC. Just use the stereo input and output of the Laptop. You will have at least 16 Bit at 48 kHz or even with the common new Laptops 24 Bit at 96 kHz sampling rate.
10 bit A/D: SNR ca. -30 dB (in the PIC)
24 bit A/D: SNR ca. -72 dB
SNR increase on 24 bit A/D: 42 dB!!!!

Forget any suggestions with any PDA's. You will have much more problems with it (tools, compilers, specs., etc.).

Implementing the code on Laptop would be very fast and easy. You will have enough number crunching power for this purpose.

[gwzd]

Hi,


Forget any suggestions with any PDA's. You will have much more problems with it (tools, compilers, specs., etc.).

Actually not, tools and compilers are available. You don't necessarily have to run Pocket PC on it and the advantages of the PDA are obvious.
GSSI newest GPR system runs on Windows CE and Mala Geoscience on Linux.

[Max]

Hi,
Thanks for ms.nomi and gwzd ...
yes, PDA can be better in light weight, but did PDA cpu enough for this job?

also programming of pda is which language? what is usb interface for PDA?
if you have any idea please share it to use for our purpose...

anyway,for laptop i found a usb interface with PIC18F4550 to start:
i am waiting for any idea, thanks...

Hi,
go here:

https://www.geotech1.com/thuntings/s...ead.php?t=7146

You will find it amazing...

Just increment last number to see next page each time...

Could give you ideas...

Kind regards,
Max

[Aziz]

Actually not, tools and compilers are available. You don't necessarily have to run Pocket PC on it and the advantages of the PDA are obvious.
GSSI newest GPR system runs on Windows CE and Mala Geoscience on Linux.

Ok, I wish you good luck!
But you should go back to blackboard, making some math on this. Then contact me.

[gwzd]

Ok, I wish you good luck!
But you should go back to blackboard, making some math on this. Then contact me.

Sorry, but math on what? The OP just wanted to digitize some data and analyze it. A PDA is a computer like any other, just a little bit stripped down, but not much. Consider the Tek scope 7854 working on several orders of magnitude less computing power than a PDA.
There are plenty companies using PDA's for many purposes including scientific and amateur. Check the following links:
http://www.ni.com/support/labview/pda/ (the easy way to code)
http://www.geophysical.com/Profiler.htm (professional device)
http://www.virtins.com (amateur use)
There's no need for blackboards anymore. Some people can code and some cannot. But one shouldn't discard a technology just because being in the second group, or?

[vistac2000]

Hi friends,
It is very useful and interest for us, that we find a way to examine Tx & Rx signals in real time by a computer, it is guide me to make a best performance metal detector in pcb version,
with pc we can produce a clear and stable signal with desire frequency or (desire pulse with delay) as we wish,
for this purpose we can many software that find in internet or can write a customized program by many computer languages,
I think hardware for this job is more important,
for this job i need a good and low noise amplifier for Tx and Rx signals that send and receive to coil, Are these amplifiers is common audio amplifiers?
How much power need for these amplifiers?
what is the best coil for this job?
remember that we want get best depth and best discrimination...
With best regards...

[gwzd]

Hi friends,
...that we find a way to examine Tx & Rx signals in real time by a computer, it is guide me to make a best performance metal detector in pcb version,
with pc we can produce a clear and stable signal with desire frequency ...

Are you going to do the hardware and the software parts by yourself? Isn't it a bit ambitious to make the *best* metal detector without prior knowledge or experience in the subject? Or perhaps you do have both and care to share, then you could join the following group:

http://thunting.com/geotech/forums/s...ad.php?t=13478

wish you luck
RA

[Aziz]

There's no need for blackboards anymore. Some people can code and some cannot. But one shouldn't discard a technology just because being in the second group, or?

Hi,

my suggestions refer to my personal experience. I have designed a 80 MIPS DSP board for this purpose former. I also programmed many PDA's, Windows CE etc. From the practical point of view, you should use a best known host system. This is definitely an usual PC system. Otherwise you will have much more problems (cost, delay, information suffering, etc.).

I also proofed the question, whether a VLF on a simple Laptop is possible: Yes, more easier than you will ever believe.


It is just a matter of software engineering (yes, I am a software engineer - embedded systems engineering is my particular focal point).

You should trust on me! I am telling you no stories. Please, go back to the blackboard. This is the first important step!

Aziz

[gwzd]

Hi,

my suggestions refer to my personal experience.I have designed a 80 MIPS DSP board for this purpose former. I also programmed many PDA's, Windows CE etc. From the practical point of view, you should use a best known host system. This is definitely an usual PC system. Otherwise you will have much more problems (cost, delay, information suffering, etc.).

I also proofed the question, whether a VLF on a simple Laptop is possible: Yes, more easier than you will ever believe.


It is just a matter of software engineering (yes, I am a software engineer - embedded systems engineering is my particular focal point).

You should trust on me! I am telling you no stories. Please, go back to the blackboard. This is the first important step!

Aziz

Your personal experience is limited, as usual, by your personal skills. I doesn't appear to me you have programmed many PDA's successfully otherwise you shouldn't be that terrify of them. Because it is hard for you it doesn't necessarily mean it's hard for other people too. Don't flatter yourself that much, it is not healthy. I on the contrary will always encourage people to try themselves in new stuff and new challenges. The OP wanted to do something apparently he doesn't know much about it, why not use the opportunity for him and learn something he might actually use?

I'm an EE not a software engineer, but I do manage four of them. Any of them can go around this simple task in less time than you will ever believe. It's, as I said previously, a matter of skills not the technology.

It's always easy to say take two more terabytes of memory for making a calculator, "anyway the customer has no other choice!" This kind of attitude is what bugs me at the first place.

About your stories, I do believe you are truly sure about the nonsense you are talking about. But it doesn't make it right anyway. I will let the blackboard alone and you should go back to school. The first step into getting hired with us is to prove you have an open mind and can see the problem from different angles. Now, that's an important step!

If you are your own boss take my advice and learn a bit about solving a problem with the smallest possible amount of resources. It might help you to get some good stuff on the market and you might actually get someone to buy them! If you are hired somewhere, then I'm sorry for your boss. You wouldn't last a day with us.

Regards
RA

[Aziz]

Hi gwzd,

Your personal experience is limited, as usual, by your personal skills. I doesn't appear to me you have programmed many PDA's successfully otherwise you shouldn't be that terrify of them. Because it is hard for you it doesn't necessarily mean it's hard for other people too. Don't flatter yourself that much, it is not healthy. I on the contrary will always encourage people to try themselves in new stuff and new challenges. The OP wanted to do something apparently he doesn't know much about it, why not use the opportunity for him and learn something he might actually use?

I think, you misunsderstood me. The problems regarding PDA's is commonly to the lack of specifications and informations. If you not work directly for a such PDA company, it is hard to get some technical informations and tools.

It's always easy to say take two more terabytes of memory for making a calculator, "anyway the customer has no other choice!" This kind of attitude is what bugs me at the first place.

I would like to have such a calculator. Particularly in my Laptop!
Calculation is proportional to the memory capacity! Particularly true, when you have much more to calculate. Why this is so: just ask a software engineer.

About your stories, I do believe you are truly sure about the nonsense you are talking about. But it doesn't make it right anyway. I will let the blackboard alone and you should go back to school. The first step into getting hired with us is to prove you have an open mind and can see the problem from different angles. Now, that's an important step!

Yes indeed, I was gone to the blackboard. And last night again:
http://ocw.mit.edu/OcwWeb/Physics/8-...ures/index.htm
It is amazing! I like the professor.

If you are your own boss take my advice and learn a bit about solving a problem with the smallest possible amount of resources.

Yes I did it! Only the coil and laptop. No electronics!

BTW, I do not like german bosses. Also I do not like krauts anymore and therefore I am the boss of myself. I am doing this stuff fulltime now. And I like it.

So see this as a big challenge to convince me your projects with PDA's!

Aziz