Measuring PHASE SHIFT IN PI

[Tinkerer]

Circuit that detects time positions of peaks and valleys in the input-voltage waveform.

http://www.edn.com/contents/images/6442431.pdf

Esteban,

thanks for the feedback.
I will post some pictures of the PIVOT to illustrate what I am talking about.

Tinkerer

[Qiaozhi]

that's the point: any serious attempt of implementing disc in a PI design must face that any VLF-IB design is fairly superior to that: facts.

Maybe Tinkerer will have more success.

[Max]

And how successful is the discrimination when compared to a VLF-IB?

that's the point: any serious attempt of implementing disc in a PI design must face that any VLF-IB design is fairly superior to that: facts.

I think most people here belive a true fault free discrimination in PI is possible... though till now not demonstrated by any commercial product.

It's like with eco-cars.... you'll put inside the hydrogen... oh yeah...
But how the hell that hydrogen is produced ??? By some nuclear reactor generated current , eh ???

Then add to the "clean" hydrogen the costs (not only money) for a nuclear plant here and there and you'll see that probably the cleanest REAL USABLE car around is fueled by elephant $hit made METHANE!

Same apply to PI... someone will make the people think they can get everything easy... power (depth) and accurancy (discrimination) and it isn't. It's never so simple in real world.

Kind regards,
Max

[Qiaozhi]

Yes , pi detector be able working at discrimination mode .
I did it .
Best regards.

Would you mind telling us how you do it?

Tinkerer

And how successful is the discrimination when compared to a VLF-IB?

[Qiaozhi]

During many experiments doing ON TIME sampling, I have found that there is some kind of "PIVOT" in the response.
It is like there was an "INVISIBLE SINE WAVE" in the response from the target.
The "PIVOT" would be the point 0 where the "relative polarity" changes.

I believe that with the right signal processing we should be able to read the phase shift in this sine wave, caused by the different metals, just as it is done with VLF.

I SAY PI TARGET DISCRIMINATION IS POSSIBLE

I am starting this new thread inviting everybody who believes that it is not possible to do target discrimination with PI, to discuss the subject with others who believe it is possible.

Tinkerer

Hi Tinkerer,

What sort of effect does the balance between the coils have on the target response during the ON period? I would imagine that this adjustment is quite critical.

[Tinkerer]

Yes , pi detector be able working at discrimination mode .
I did it .
Best regards.

Would you mind telling us how you do it?

Tinkerer

[Esteban]

Circuit that detects time positions of peaks and valleys in the input-voltage waveform.

http://www.edn.com/contents/images/6442431.pdf

[aft_72005]

I SAY PI TARGET DISCRIMINATION IS POSSIBLE

Yes , pi detector be able working at discrimination mode .
I did it .
Best regards.

[Tinkerer]

During many experiments doing ON TIME sampling, I have found that there is some kind of "PIVOT" in the response.
It is like there was an "INVISIBLE SINE WAVE" in the response from the target.
The "PIVOT" would be the point 0 where the "relative polarity" changes.

I believe that with the right signal processing we should be able to read the phase shift in this sine wave, caused by the different metals, just as it is done with VLF.

I SAY PI TARGET DISCRIMINATION IS POSSIBLE

I am starting this new thread inviting everybody who believes that it is not possible to do target discrimination with PI, to discuss the subject with others who believe it is possible.

Tinkerer