Minelab MPS patent could be invalid

[unregistered_user]

Here's another idea:

What about a half duplex near field magnetic transmitter with a variable width coded mono pulse train, allowing ringing to subside before the next pulse into an over/under damped magnetic loop with nyqist limit time or frequency sampling one or two coils then using subtraction of the returns to remove clutter. Should be a piece of cake with todays gear.

[bugwhiskers]

The following link shows a GB method that nulls out the ground from 2 different TX pulse lengths. It inherently also cancels the Earth Field.

The circuit shown is not a schematic, it just shows the principle.


http://goldprospecting.invisionplus....=0&#entry11868

regards
bugwhiskers

[Woody.au]

No bites yet?

[unregistered_user]

No bites yet?

There's some dudes in trench coats outside my front door.

email me.

[robby_h]

Bugwhiskers,
You said, "You had a cheap shot at me some time back for trying the front end blanking FET's. You accused me of "pinching" ML's idea”. Take the time to look at the Corbyn circuit and tell me what you see preceeding the pre-amp".
Perhaps someone on your forum can tell you the difference between Corbyn's and Candy's RX switch and the advantage the latter has? Woody keeps harping on it. Look at Corbyn's actual circuit, not the equivalent circuit.

You said, "The SD2000 was aptly described by Candy as being two detectors in one. Channel 1 and Channel 2 form the two detectors and far from using the two different TX pulse lengths to differentiate the ground the late sample in each channel removes the gross ground signal with the remaining fine correction signal coming from the GB channel". This is obviously incorrect and one minute you are saying Candy pinched Poole's method and then you say he doesn't use it?
Wrong in both cases! You can't read Corbyn's circuit or patent so how can you comment on Candy's?
You then post this
http://goldprospecting.invisionplus....=0&#entry11868
Aren’t you getting a bit dizzy?

You did raise a point though on Finders. You said, "I notice you neglect to mention to your fans here the benefits of SMR and V2C".
I'm afraid one predictable flaw has been obvious from the beginning and you just demonstrated another predictable flaw in a recent post on your forum combined with the video you posted on Youtube. I can't believe that you, Woody or your forum "experts" haven't noticed this. These problems will only become obvious with increased gains and you will have to do this if you hope to be competitive.

[robby_h]

Woody,
You said, "Robby H, why do the modified older detectors beat the pants of Minelabs GPX-4500?"

Who spread this silly rumour Woody? It wasn’t you was it?

"Why does Minelab have so many recalls on their detectors?" To fix a problem or problems. This leaves you wide open to the following question, when did you ever recall detectors you have "modified". None of the mods you have proposed on this forum work! Not even one! We can step thru them if you wish?

Fact… the only public mod that actually works without some nasty unwanted side effect and if the ground permits is where the fundamental clock frequency governing the pulse length and timings is raised. This advances the timings but reduces the pulse lengths. This makes some “invisible” nuggets “visible” because of the advanced timings, but the advantage falls off on larger bits because the peak coil current falls with decreased pulse length.
This was first performed on the 2000 by a guy in WA not long after the 2000 was first released so nothing has changed much since then.
The gain mod for the 2000, which you do in one video, appeared on the scene several years ago but the gains can’t be activated at all on any goldfield ground I frequent here in the eastern states without suffering huge target-masking ground noises that simply don’t exist when using a stock 2000 or any of the GP series. This mod also makes the 2000 susceptible to static fields and permanently magnetised rocks etc.
Lowering the clock frequency results in a good percentage of typical small and large nuggets being missed by the 2000 but often easily detected by a 4500 in Enhance mode so the guy will see an impressive demo at a test bed using a selected large nugget, coke can or the infamous al block and then wander all over the paddock wondering why he doesn’t get nuggets missed by the stock models.
"Oh well, my hand was forced yet again". Your hand wasn't forced Woody. You tell everyone to stay on topic and then use something off topic in the hopes it will hurt ML. Nothing else.

"Minelab detector work differently to the Patents they hold. The early ones are glorified GoldScan designs with stacks of Gain and a low noise design approach".
You have shown quite clearly here and on your website and on the forums that you don't know how ML detectors work or how to read the circuit or patent so how can you say this? If you could read the 2000 circuit then you would jump in and offer the GPOZ crew a solution to at least one of their problems.

[robby_h]

Doug is still at it, I log back on today and find him permanently attached to his keyboard, and insisting I'm hiding because I need help with my answer. Some of us do go away now and then and have other things to do.
Unregistered user,
Doug says (on his forum) that your post #85 is a "clincher". Posts 112 and 118 supposedly destroy me? I only skipped thru these but it seems you are saying the 2000 measures phase shift to cancel the ground and this isn't so. Poole's patent has means to adjust phase shift but this doesn't apply to the 2000.
Too much speculation in your posts so I didn’t read them all. I suspect you are part of the GPOZ crew? I didn’t know you could register twice here? Carl?

We still need to get the basics right.

Re patent GB2004069. We can use sine wave, square, or a noise generator but it is IB if we use a balanced coil to receive during a period when the transmit field is changing.

There is a distinct difference between "two different frequencies" and "two different pulse lengths". Poole’s method is IB. He looks at alterations to the transmitted signal to cancel a ground component. Candy doesn’t look at the transmitted signal at all to do this. He instead looks at a result during a period of non-transmission and that result is dependent on the history of the applied field (novel)! How anyone can say that Candy’s patent is a logical extension of Poole’s IB patent is beyond me! The argument should actually end here!

Of coarse we can find ground that differs but in most cases inland soil is primarily reactive, as is dry seaside sand. Wet seaside sand is primarily resistive.

At the risk of sounding like a parrot, in patent GB2004069, Poole attempts to cancel conducting wet seaside sand and the purely reactive component. He makes no mention of cancelling ironstone soils.

We see the same thing in patent GB2041532 where he attempts to cancel eddy currents induced in wet seaside sand at pulse switch off and makes no mention of cancelling ironstone soils, which are pulse length dependent! In other words, he says he cancels an exponential decay curve!!

Poole's patents risk cancelling short TC objects. Candy's patent doesn't.

Poole applies high gains to one channel. This isn't the case with ML detectors.

Neither of Poole's patents can cancel saline soil (Poole's ground) mixed with ironstone mineralisation (our Oz goldfield ground).

Candy cited GB2041532A to show that Poole was cancelling eddy currents induced in saline soil at switch off, not the signal from ironstone mineralisation, which is dependent on the history of the applied field (novel).

Poole attempts to cancel eddy currents induced in the ground, Candy waits until these eddy currents have decayed, or at least to a level where they can be handled by filters, as does Foster, Whites, Garret and everyone else.

Eddy currents induced at switch off in saline soils aren't pulse length dependent, whereas the decaying signal received from ironstone mineralisation is pulse length dependent, provided certain conditions are met.


Poole's patent doesn't universally cancel the differing volume of the conducting ground material under the coil. The GB would need to be adjusted to counter this whereas ML pi detectors aren't affected by the quantity or volume of poorly conducting ironstone mineralisation under the coil.

Poole's states that induced eddy currents in both the ground and the metal target decay exponentially but this isn't correct. Very few metal objects behave this way, including coins. Gold nuggets don't!!
This might be okay if it doesn't affect the outcome when looking for man made objects at the beach but it does in Poole’s case and he obviously isn't aware of this.
Poole also says that metal targets aren’t substantially affected by frequency. This isn’t technically correct and also alters the outcome. A broad range of sort after metal objects are also pulse length dependent so, again, how does Poole’s IB patent compare with Candy’s PI patent?

Logical extensions, (if you can actually make a comparison) such as taking a late sample from an early sample or multiple samples after one pulse length can’t compete with Minelab and the same applies if you form two GB channels after one pulse length so most of the discussion along these lines is pointless.

To top this off, we now have the instigators of this thread claiming Candy pinched Poole’s idea but didn’t use it?
I.e. Doug, Bugwhiskers and Woody et al, are now promising to prove that a ML pi detector is just simply two detectors in one and that the claims made in the patent are just spin. (This should be good!!!!)
On the other hand though, they are currently trying to come up with a way to “fit” Poole’s IB method to a pi using two different pulse lengths!!???
In other words, they started this argument when it is obvious they don’t even know how a ML pi works or the tech differences between the two methods!


Candy’s Oz patent, when I purchased it from the Oz patent office over a decade ago had a page attached stating that a large well known large detector company (almost certain it was Whites) disputed the power saving feature, nothing else! They didn’t dispute Candy’s multi frequency IB patents either!
Whites and others also own multi frequency IB patents. Are these also null and void because of Poole’s patent?
Anyway, we shouldn’t have long to wait. Woody has sent the patents to a couple of his eggspurts in the USA. This should also be good!

[unregistered_user]

Roby_h

Thankyou

[bugwhiskers]

Hi Robb_H,

I simply asked you to look at Corbyn's patent and tell me what you saw preceeding the pre-amp, verbosity is no substitute for a simple honest answer.

I notice also that for the fourth time you have refused to withdraw or explain your comment that the QED is a copy of the SD2000.

If you like I can scan the document and paste it here where Candy describes the SD2000 as being 2 detectors in one.

If you like I can also scan another section of the same document where he states that the SD2000 cannot tolerate mains interference. SMR does it perfectly.

In a hostile EMI environment can you name another method that digitises a signal better than an Integrating ADC (V2C) ?

What out of the box contribution have you made to the detecting fraternity? Have you been relegated for life to singing the praises of another. You don't have to be very clever to memorise patents and spew out that information like a parrot. Try contributing something worthwhile that is the fruits of your own labour and you may gain some respect.

Now that the Poole patent has been bought to light, anyone is free to make full use of the "Natural Physics" of ground being differentiated by different pulse lengths/frequencies. If this results in the eradication of the Gold Tax, many will rejoice.

regards
bugwhiskers

[Esteban]

I guess in theory it's possible to configure an IB coil so it is "balanced" in the presence of ground and unbalanced (alarm) when a target comes along.

regards
bugwhiskers

An idea: In general, low/medium mineralized soil give no much signal, but perturbs. Think that final stage (blocked here) can be only open in presence of target. For this implementation I think can be useful a peak detector inter-stages. Can be an adjustable peak detector.

Regards

Esteban

[robby_h]

BW,
I‘m sure Carl must be getting sick of this.
You said “I simply asked you to look at Corbyn's patent and tell me what you saw preceeding the pre-amp, verbosity is no substitute for a simple honest answer”.
And I said to look at the actual circuit and forget the equivalent circuit? What do you see?

“I notice also that for the fourth time you have refused to withdraw or explain your comment that the QED is a copy of the SD2000”.
I have addressed this before and you ignore what I write and instead nitpick on something trivial.
http://www.finders.com.au/forum/view...785e0f81e8265d
And on the following page if anyone is interested.

“If you like I can scan the document and paste it here where Candy describes the SD2000 as being 2 detectors in one”.
I agree he said that, but he didn’t say it is “just” two detectors in one. Read the rest of the article.

“If you like I can also scan another section of the same document where he states that the SD2000 cannot tolerate mains interference.” I agree.
“ SMR does it perfectly”. Bugwhiskers…, hopefully for the last time, get the thing finished and truly competitive with a Minelab pi detector and then tell us how well it cancels mains interference.

“In a hostile EMI environment can you name another method that digitises a signal better than an Integrating ADC (V2C)?” As above.

”What out of the box contribution have you made to the detecting fraternity? Have you been relegated for life to singing the praises of another”. It Appears so! “You don't have to be very clever to memorise patents and spew out that information like a parrot. Try contributing something worthwhile that is the fruits of your own labour and you may gain some respect”.
Respect from you, Doug, Kris, Woody et al? I joined your forum under another id and intended to make a contribution. I did when I warned you that using two identical fets to switch the coil and for the rx switch might easily result in the rx fet diode avalanching before the other. You actually thanked me but Doug figured out who I was when I attempted to explain that other static fields exist, apart from the Earth’s field, such as those from permanently magnetised rocks etc and the rest is history. Why would I make a contribution to your project after what followed?

“Now that the Poole patent has been bought to light, anyone is free to make full use of the "Natural Physics" of ground being differentiated by different pulse lengths/frequencies. If this results in the eradication of the Gold Tax, many will rejoice”.

Groan…. see post #141 and tell Doug that Poole’s reference to soil iron oxides and ferrite materials refers to the purely reactive component as is clearly shown by the loop in Poole’s “automatic” circuit, not our Oz mineralisation!!

We see this in a large number of patents when the inventor doesn’t encounter our problems.
You really need to ask yourself how many patents actually see the light of day and result in an efficient working commercial model, perhaps one in a thousand? I don’t really know but the real proof is in the pudding!

[robby_h]

http://goldprospecting.invisionplus....=0&#entry11915
Typical Doug, two links to the same patent when he could have linked to 199916505 and WO9931529A, not that it matters.

Bugwhiskers,
If you can't see the obvious difference between Candy's and Poole's patents then what is the point in me responding to this?
You completely ignore 99% of what I write and nitpick at something trivial that has little bearing on the argument. Another poster such as "Unregistered User" only has to query something I write and Doug posts a banner on his forum saying "robby_h shot down in flames again on Geotech" or "comprehensively destroyed by posts 112 and 118" and you agree? If this is being shot down in flames then every poster here has suffered the same fate at one time or another and Doug has been shot down in every argument he has ever had!! He should be just a little pile of ashes by now!

Doug will definitely make something of this but do you really expect me to waste time typing out a long drawn out response just so you can ignore it, or pick on some trivial point. I think not!

My advice to you is to just build a multi-period pi based on their patents and then sell it instead of trying to convince others to test the water for you! Otherwise, get one of Doug's forum "experts" (he is always calling on them to help explain something. Never gets an answer tho!) to translate these patents for you. You have come unstuck before when you just copied and pasted a few selected paragraphs from one patent in a silly attempt to destroy a ML patent. Short memory eh?

This thread has become a complete waste of time. Just stick to what you know best, ie, speculation and rumours and criticising anyone who doesn't toe the GPOZ party line.

[Woody.au]

At great risk of being called a smart *** I will venture one question. Why are all the Candy patents only referencing DD coils? I take that its ok to use MPS with a Mono?

[bugwhiskers]

Robby_H,

I am most certainly not going to help you to pursuade Carl to close this thread down by posting responses to you that may seem to be inflamatory and turning what has been a very popular thread into a sledge fest.

Readers are at liberty to see what I have written and your responses and judge for themselves.

Of course you can always argue that ML machines have the runs on the board but did you contribute anything worthwhile in real terms to that success or did you just parrot patents, criticise and intimidate those dedicated individuals who strive to turn the tide for the benefit of their fellow prospectors?

regards
bugwhiskers

[Carl-NC]

It seems that the real purpose of this thread is for thinly-veiled bashing of Minelab, Bruce Candy, and anyone who argues in their favor. I consider Minelab to be a worthy adversary who has made some good products. As I've told folks before, if you don't like their products, then there is a simple solution: don't buy their products!

As for Bruce Candy, I don't know him personally, but the comments from people who do know him (including here at White's) are that he is a nice guy and a very competent engineer.

On patents, you can take most any patent from most any company and do the same exercise of dissecting its claims and prior art. Based on my experience, I'll guess that about 50% of all circuit-based patents in the last 10 years can be overturned or severely reduced in scope. In general, I don't consider patents to be a quality indicator of merit.

On the Poole application in particular, I fail to see an obvious relationship to Candy's '96 patent method. Even though frequency domain and time domain are mathematically interchangeable, the actual methods used to implement them can be quite different and unique. Anyone who feels Candy's method is a rip-off of Poole's will need to explain it to me, because I don't see it.

I also don't see why some folks get all worked up over Minelab. If you want to beat Minelab, then do it with a better product!

- Carl