Dual Field Pi Coils

[Orbit]

but some may not understand What I meant to say for it is the culprit translator,unfortunately I do not know English.

[Orbit]

No matter how the coil is called, it is whether it works ,and if it worked better for the mono coil kolko see here is water controversy Who was the first done it would be ,because what is happening that in this great world ,one idea can be born in two or three places simultaneously ,it also happened in the past for some great discoveries .For me it is more realistic practice than theory ,do mono coil, and do a double coil connected in series hook into the unit and see the difference specifically . In theory 2i 2 are 4 but 4 because We take it as a prefix for these numbers on a world scale Science is everywhere the same. But edfor a great scientist Nikola Tesla, it was the same he was leaving the generally accept reasoning electromagnetics reasoning electromagnetics Current science and therefore does not realize all his ideas just because it was for him maybe it was 2i 2 4 for him it may have been another imaginary number.Who understood what I wanted to say they will understand, greeting Orbit.

[Mrand]

The old coil for Surfmaster was 9.5 inch. New has 12 inches. The new coil MUST be deeper. Similarly is with SEF coils. They are deeper because are greater. If was otherwise, Minelab should stoped coils production, because don't know. Is this the truth? When the mind falls asleep, dodgers awake.
Mrand

[WM6]

Aziz, some folks have made this coil many many years ago, but we did not know then that the coil name is 'dual field'

Hi kt315,

impressive Accu!

Regarding term "Dual Field Coil" maybe would be better "Dual Sections Coil"? But if used term is ok for our English coleague it is ok for me too.

[kt315]

An induction balance co-planar coil is also a dual field coil!!!
An anti-interference coil (figure-8, double D) is a dual field coil too!!!

Aziz

Aziz, some folks have made this coil many many years ago, but we did not know then that the coil name is 'dual field'

[WM6]

The small coil inside doesn't give the general enlargement of the range. She improved characteristic of the answer head for small objects inside coil. The advantage it is visible at coils of 15 inches and more.

Exactly! And this can be easy to proven.

[Mrand]

Such coil is well-known for a long time. This isn't the original Whites idea. First was Fisher-Impulse. I also applied such coil of 15 years ago in detectors intended to the usage in the sawmill. The small coil inside doesn't give the general enlargement of the range. She improved characteristic of the answer head for small objects inside coil. The advantage it is visible at coils of 15 inches and more.
Whites had a ready coil case from other detectors (DFX, MXT). It made the new search head. Uses magic words "Dual Field" sells this as the extraordinary novelty. Because people wish novelties, buy this willingly. Amen
Mrand

[WM6]

Can't say I was impressed with the TDI though. Spectra V3..now THAT'S a WHOLE different ball game.. VERY nice!!

Probably you are one more impressed by user interface.

Did you done comparative tests between mono and dual field coils or you only theoretize here?

[Sean_Goddard]

OK, maybe I'm missing the point here, take a look at the two analyses of my interpretation of a DF coil, I don't see ANY benefit over a single field, although in theory DF SOUNDS like it would be a good idea.

Maybe my analysis is wrong but from what I see as an output, DF is just a marketing gimmick and I do NOT expect this from Whites as I thought they were above that sort of thing.

Can't say I was impressed with the TDI though. Spectra V3..now THAT'S a WHOLE different ball game.. VERY nice!!

[Sean_Goddard]

The USPO is so overworked they don't even bother checking anymore. I've seen many, many beeper patents which are so similar they should never have been granted in the first place.

Only recently I supplied White's with information which helped them nullify one of Minelabs as they had prior knowledge of the alleged infringment based on one of MY designs back in 2002 (some FOUR years+ before ML filed (HAHAHA UP YOURS LAMEBIN - now you know who STUFFED YOU)!!

Consider that patents were ORIGINALLY designed NOT for protection, but for dissemination of information.

If you want a real laugh, look at some of the patents applied for from Japan, they're absolutely stupid in about 90% of cases, looks like the USPO are granting anything in patents now too.

I heard of one guy who took an existing patent, an applied for it under his OWN name, he was about to be granted it when he 'fessed up an told the USPO what he'd done. I imagine they were pretty nonplussed with that, their fault though I think.

To sum up, just because a company hold a patent doesn't mean the contents of that patent are of any REAL world worth OR indeed that the patent is valid (like most of Limebans for example - ).

I'm pretty sure there are many examples of patents which are VERY similar to work done by others who never bothered to patent because of the costs involved. Not everyone has $10K+ lying around unless they are a big business, and not everyone NEEDS to protect their work, especially like a LOT of the work done on this forum where we share.

Magnetic analysis software and CHEAP too!! http://www.vizimag.com/ordering.htm

[Rov]

Bump! thanks for your private emails,It works very well for you.
Regards Rov

[Rov]

Darp,make a 11 1/2 inch loop with 16turns of medium duty tin plated multistrand wire. will give you about 0.4ohms coil resistance.
next make a 6 inch loop for inner with 19 turns medium duty tin plated multistrand wire. this will give you about 0.4ohms coil resistance also.
wire these two coils in Series with each other,an now you will have a very deadly coil to use on your TDI or other PI machines.
Regards Rov

[Darp]

Actually Ism says its in Series.

[Darp]

Parallel, pic

Have seen a pic by Ism on TDI Forum http://img443.imageshack.us/i/dfcoil002.gif


He built this for his TDI and it looks like parallel wiring, which means the two coils need to be matched resistance wise fairly close. So both fired in parallel is now my best guess. It helps to know this when using my TDI and thinking of mods to the technology.

Thanks to all for your help on understanding this.

Cheers

[Darp]

Interesting. So I was off. It is both inner and outer firing and receiving at same time.

Guess it is possible that under some circumstances the inner and outer might pick up a signal from the other that the originator does not pick up.

From what you two have said the coils would be in series, which is simple.

Thanks, am learning.

Cheers