PI discrimination is possible

[kt315]

And, most importantly, "all without the Arduino". Mustafa has pasted a whole PC + oscilloscope all over his metal detector, but as long as there's no Arduino then it's OK. kt315 doesn't hate bloated hardware, only Arduinos.

I wonder what Physics are behind Mustafa's curtain of GUI bells and whistles, but I have the impression he doesn't care as long as customers get hypnotized by the screen show and buy.

i can add especial points or a connector for the arduino on Bara and DP pcbs. only say what connect to.
i do not see a problem.

[daverave]

What comes first to me is depth on low conductive items....i cannot understand why a pulse machine has to have a menu system and many parameters like as in the mustafa videos....without good depth and discrimination what the hell with menu driven displays !!!! im sorry but im not convinced with mustafa's detectors...plus he cannot even be bothered to answer questions.

[Teleno]

Hi kt315...ive looked many times at the mustafa videos and although the video's look impressive im not that much convinced cause they always waive a sheet of copper in front of the coil and ferrous pliers which of course will give a good signal...you hardly ever see a small ferrous nail or small gold ring waived in front of the coil...ok great looking lcd displays but do they have the depth on low conductive items and does the discrimination work at good depth on small ferrous items ?????? when you ask questions to these people they never answer which makes me very suspect of their technology.

And, most importantly, "all without the Arduino". Mustafa has pasted a whole PC + oscilloscope all over his metal detector, but as long as there's no Arduino then it's OK. kt315 doesn't hate bloated hardware, only Arduinos.

I wonder what Physics are behind Mustafa's curtain of GUI bells and whistles, but I have the impression he doesn't care as long as customers get hypnotized by the screen show and buy.

[daverave]

and what? Mustafa does PI's with the disc like cooking hot dogs!

https://www.youtube.com/watch?v=uEXe5N0ZlZE

and all are without the arduino )

Hi kt315...ive looked many times at the mustafa videos and although the video's look impressive im not that much convinced cause they always waive a sheet of copper in front of the coil and ferrous pliers which of course will give a good signal...you hardly ever see a small ferrous nail or small gold ring waived in front of the coil...ok great looking lcd displays but do they have the depth on low conductive items and does the discrimination work at good depth on small ferrous items ?????? when you ask questions to these people they never answer which makes me very suspect of their technology.

[ODM]

Your system, your choices. Just discussing the facts, if it is welcome. No hostility.

[Teleno]

Slowing down the LR tc will give thicker skin depth.

A PI has to settle for a coil inductance adapted to the tau's of the itended targets. If you're hunting for large taus you'd better use a larger inductance in your coil. This will slow down the turn-on accordingly and allow you to discriminate in your target range.

There's no universal solution for any coil to detect and discriminate any target. A PI can only be optimised with a certain type of targets in mind.

[ODM]

Thinner skin depth will mask target ID based on inductance shift (as in BFOs), so frequency eg. rise time will be critical. Slowing down the LR tc will give thicker skin depth. Some PI engineers suggest series R with coil for other reasons.

[Teleno]

The turn on has a different dI/dt so it is in effect another pulse.

Turn-on time depends on inductance. Diamagnetic targets reduce inductance, paramagnetic targets increase inductance. Just simple Physics.

[ODM]

From my replies to you, Teleno, you know that I do not intend to harm the efforts, only to raise points I believe have not been considered thoroughly, or to point out something done earlier, such as discussing your discrete frontend project.

Your previous postings regarding math in ground cancel are a good example of physics. Physics is models of our world in mathematics, not cloak-and-dagger secrets!

I ask that you don't go down the path other people on this forum have gone and listen to Carl's experience in the industry if you won't listen to me; in previous threads his advice was to either come forward with all information or to keep a lid on a project until it is patentable, if the intention is to make it your own IP. Those are the two ways to go.

Flaunting secret methods and such makes for long threads but ultimately doesn't result in synergy if others cannot inspect process. Scientific method relies on publishing findings so they can be reproduced, but does not discredit the original work!

[kt315]

Although it is possible to provide some level of discrimination by using the turn-on ramp, it does not provide discrimination for deep targets.

btw Chance of Andy is working in two algorithms - for near targets and for deep targets. much of western people do not know
that.

[Teleno]

Although it is possible to provide some level of discrimination by using the turn-on ramp, it does not provide discrimination for deep targets.

Deep targets are a discrimination problem to any method. Simply dtecting them is already hard enough.

At any rate, discrimination never reaches the same depth as detection. We'll have to live with that.

do in that whites mannere, only delete this 'vdi=' from image
https://www.youtube.com/watch?v=Xr7k28_Pgv0

White's MXT is not PI. FAIL.

[kt315]

do in that whites mannere, only delete this 'vdi=' from image

https://www.youtube.com/watch?v=Xr7k28_Pgv0

[ODM]

The turn on has a different dI/dt so it is in effect another pulse. There is a patent on some halfsine pulsed and another CC pulsed detector that sample during ontime, during transient. This is more information than a single frequency or single decay detector has, eg. the trick is not in processing decay.

However if there aren't separate ramp profiles or pulse widths, it runs into the same ambiguity problems that single frequency VLF detectors face.

Also on time sampling is not a "trick" or much of a secret, especially with IB coils or separate inductors, please don't lower the standard of discussion on this board back to times of secret "magic formulas and minelab killer detectors".

[Qiaozhi]

My set up is a standard front end. I'm using the turn-on ramp for discrimination instead of the off signal.

This technique can be easily applied to Surf PI, Barracuda etc. as an add-on.

Although it is possible to provide some level of discrimination by using the turn-on ramp, it does not provide discrimination for deep targets.

[Teleno]

I agree with Teleno .. there may also be other ways to do it however "funny" damping and frontend ccts are a winner ... alot harder ( but not impossible ) with standard damping / frontends.

My set up is a standard front end. I'm using the turn-on ramp for discrimination instead of the off signal.

This technique can be easily applied to Surf PI, Barracuda etc. as an add-on.