Best discriminating pi for LARGE loop?

[Darren in NC]

I know many of you are seeking a pi that will discriminate for smaller coils. Has anyone built several homemade pi's and found which was best designed for a large loop and indeed discriminates well? XR71? DeltaPulse? DBP2010? I've got great coils, I just need the best control unit. I understand much of this will be a matter of opinion, but that may be all I have to go on for now :-)

My ultimate goal is to build the best discriminating pi designed for a large loop to hunt underwater targets. I'd like to do this without buying the Pulse Star or Lorenz.

[Geo]

I know many of you are seeking a pi that will discriminate for smaller coils. Has anyone built several homemade pi's and found which was best designed for a large loop and indeed discriminates well? XR71? DeltaPulse? DBP2010? I've got great coils, I just need the best control unit. I understand much of this will be a matter of opinion, but that may be all I have to go on for now :-).

:confused: Noone can discriminate. DeltaPulse or XR71 only can reject small pieces of iron and ceramics. I dont know any PI detector that can discriminate as an VLF detector.

[Darren in NC]

:confused: Noone can discriminate. DeltaPulse or XR71 only can reject small pieces of iron and ceramics. I dont know any PI detector that can discriminate as an VLF detector.

Hello Geo,

I have a friend who owns a Pulse Star II, and he says it indeed does discriminate - but only for items larger than a softball. That's why I'm focusing on the large loop. Has anyone tried a large loop on the XR71 or Deltapulse? I agree that with the smaller coils that pi's don't discriminate much at all. So far, only VLF has that claim on smaller coils.

However, with the Pulse Star II or Lorenz, there's no meter saying gold or silver. But it basically discriminates in that it tells you whether it's ferrous on non-ferrous when you're using the large 1mx1m loop. There's got to be a homemade machine that can do the same.

Best,
Darren

[Leto]

PI discrimination

I own PI with discrimination. It is PD3200 http://www.pulsediscriminator.com/index.htm

It can discriminate between ferrous and nonferrous metals very well. I have not tested it with coils larger than 50cm but I doubt it will affect discrimination much for medium sized objects.

PI's can discriminate - that's a fact and all I know - but I'm sure there are people on this forum who can explain it's principle...

[Darren in NC]

Leto, thanks for your response. How small do your coils get where you can still have good discrimination? I am not familiar with the PD3200 other than I've seen it advertised.

Best,
Darren

[Geo]

I own PI with discrimination. It is PD3200 http://www.pulsediscriminator.com/index.htm

It can discriminate between ferrous and nonferrous metals very well. I have not tested it with coils larger than 50cm but I doubt it will affect discrimination much for medium sized objects.

PI's can discriminate - that's a fact and all I know - but I'm sure there are people on this forum who can explain it's principle...

I read about it but it discriminate only between ferrous and no ferrous. I said that trere is not PI to discriminate as a vlf detector. Ivconic is own of a pulse star II so he can tell us about the ability to discriminate.

Regards

[Lake]

What is this then?
http://fandy.front.ru/ClonePI.htm

Use http://babelfish.altavista.com/ to translate.

Translated forum:
http://babelfish.altavista.com/babel...06cc27cc73387c

[Leto]

Actually discrimination is much more complex on ClonePI or PD3200 than just discrimination between ferrous non ferrous - you get different responses for different kind of metals. Please note that I have worked with IB detectors a lot (last one was Garret1500) and I'm not here to persuade anyone.

Still waiting for someone to explain discrimination principle for PI detectors.

Oh yes..In case of PD3200 coil dimensions seem not to afect discrimination. I had roughly same results with all my coils (from 10 to 50 cm)

[Leto]

P.S.

I guess there are many PI discrimination projects out there (not just two in my last post), but have not seen any pure analogue design to build. All have microcontrolers on them.

[michael]

PIs are best for discrimination. My home made PI, which I like so much, can easily discriminate and indicates in LCD it's gold or not and gives a specific beep for gold.
other metals; Iron, copper, silvers... will be shown as Iron with a different beep. of course with 1m × 1m or 2m ×2m coil can do discrimination.
a problem is when other metals are among with gold even much less than gold size, it shows Iron.

[Darren in NC]

Michael - what is your homemade pi? How hard was it to build?

[michael]

As I have mentioned before in other threads I am not electrician and don't know much about its' hardware or structure details.
It was built by my electrician friends. they named it "LUMINOUS".
is really an analogue PI. only know coils current is about 3A.
It works with 18 volt 1.3A SLA for 1.5 hour then have to feed it external batteries.
but it works very reliable. it never gives false signal(in all metal mode) and is a real MD.
in one search mission in 2001 to an ancient cemetery ( for more than 3500 years ago) there was a natural white medium size stone which
Lorenze system 5 gave very strong beep, whereas our PI didn't give even one tektek.
I put my post just for I saw concerns subject; "Best discriminating pi for LARGE loop?"

[Darren in NC]

I understand, Michael. I am not an electrician, either. That's why I have to ask all these questions Would your friends be willing to let me buy one of their Luminous? I'd like to have one if it works with discrimination like you say.

Best,
Darren

[Geo]

Hi. I worked with a Lorenz 5 and the only discrimination is to reject the iron. The same with an Russian pi who says that discriminate but only reject the iron and lights a led. I have not worked with PD3200 or other digital detector so i do not know about them. But as i Know Eric Foster has not an analog PI detector with discrimination, the same the Whites, Fisher, Minelab etc. Maybe they have not good electronic team!!!. Last year the internet is full of PI with discrimination but where are these fantastic devices? Maybe they don't like to make money. Or maybe i am wrong.

Best Regards

btw Ivconic has a pulse star ii that can discriminate but he like to work with delta pulse that can not discriminate. Why???? It is only my opinion.

[michael]

Would your friends be willing to let me buy one of their Luminous? I'd like to have one if it works with discrimination like you say.

Hi. regarding your comments; by my heart I wish I could be a help in this case.
I am very sorry, it's infinitely impossible. As wherever we do our searchings, it is thoroughly illegal, it's too hard to import and impossible to export any kind of treasure or metal detector.
My friends built a few limited of Luminous and when was near to be disclosed their activity by intelligent service, they stopped. Because producing such detectors are illegal too.
Maybe at upcoming I put some PICs of it and the inside. Anyway excuse me.

I worked with a Lorenz 5 and the only discrimination is to reject the iron

I should add; my PI discrimination is not the same you mean or has been meant in MDing discrimination. It has not ability to reject iron or any thing else Just after finding a single metal is able to tell its gold or not with 100% reliability.

…but he like to work with delta pulse that can not discriminate. Why????

I think its due to; in detecting base is dig for everything even trashes. If you useDiscrimination, deprive yourself of greater depth. Then it is not much necessary your detector be with discrimination. This is an opinion, he can tell the real reason. I am so willing to know why??!! Best Regards to you