Comparing PI Metal Detectors Side-By-Side

[Qld Sandy]

Peter,

The answer is simple, and that is because SETA is only a partial solution and fails when abnormal geomagnetic or paleomagnetic environments are encountered,particularly when bigger monoloops are used.

I will leave it to you to explain or explore the reasons for this.

doug

Hmmmm.

And here I was thinking it had to do with the salt content in the soil on the lower slopes.

[claim jumper]

Peter,

The answer is simple, and that is because SETA is only a partial solution and fails when abnormal geomagnetic or paleomagnetic environments are encountered,particularly when bigger monoloops are used.

I will leave it to you to explain or explore the reasons for this.

doug

Doug, don't tell us you don't know!! I thought you knew everything wrong with Minelabs!!!

[Qld Sandy]

Do you mean to say Peter that you have been using a 4500 for months and yet you have no idea what SETA is supposed to do!!!!!!!

doug

I know that when I see the areas in the gully where water lies for a period of time, and when it dries the rocks have a slightly white coating, that it is probably reasonable to assume that there just might be a higher than normal salt content in that area. Next time I visit there I'll try "salt mode" and see if the detector behaves itself.

[Toad_Whisperer]

withdrawn

[Robby_H]

Doug,

SETA has nothing to do with Ferrites. It is a truly novel way of cancelling static fields for a large number of timings without needing a bunch of cmos switches and trim pots and factory adjustments for each timing. In theory, the number of timings could be almost infinite. SETA requires a processor to work and this is much more complex than anything you have planned for the QED. If you have read and can understand the patent then you would also see that it would be very silly to allow anyone to perform mods on a 4500.

You are supposed to be an ex-scientist and yet you can't, or refuse to read the patents and jump to conclusions if it suits your obsessive anti Minelab agenda.

Large coils warp more than small coils when they are abruptly tilted because of the much larger force exerted at the lugs, so you should at least check this before jumping to conclusions by removing the coil and tilting it by hand well away from the ground or metal objects, ensuring it is suitably supported and the cable can't influence the result. The trend towards making coils lighter can also make some coils more prone to flexing. Heck Doug some large coils require the operator to side step with the swing and use a slightly circular motion at the end of each swing!

Qld Sandy is correct re mildly conducting soils causing more problems for large monos and you will be faced with the same problems with the QED if you can first solve other generally unknown problems you will surely encounter. You would actually know this if you had conducted tests or even seen JP's videos. The ground Sandy is talking about can be average ground found anywhere but is often worse in the diggings and lower slopes and gullies and in sink pockets. The latter usually sounds exactly like a symmetrical metal target. You can often pick this ground by the way the coil responds when tilted because a sensitive pi can't universally cancel the varying volume of mildly conducting material under the coil and still remain sensitive and is thus prone to changes in orientation and increased coil size. BTW, BW will eventually understand what is meant by universal cancellation if he is actually using a gain of 16,000,000 (cough) and he might even perhaps understand what he is seeing when looking at the Enhance timings oscillogram on your site.

You say it is appalling that a viewer can't tell which coil is the best in your two oscillograms on the other thread but why would the average user be expected to know which is best, especially without knowing what he is looking at or if the damping is constant in each case? I could easily form an argument favouring the old coil Without more info and would also assume you have a circuit problem when looking at the newer coil's waveform. I bet BW had to explain the oscillograms to you so why dump them here without a thorough explanation?

You whinge about supposed problems with static field cancellation and yet you are very cautious in your comments re the video on this link.

The only detector actually shown sweeping across the ground when approaching a supposed target is the unmodified 3000 and the ground is obviously very quiet!!!! It appears to give a response on the first sweep and nothing thereafter, which suggests the target was a hot rock and it tracked out. If so then why didn't the modified detector track it out? I think I know after seeing what Woody does to the front end of these detectors! We never see the modified detector being swept over the ground when approaching a target and the operator has trouble developing the signal even though he supposedly found each target with this machine, and notice the excessive noise when the coil is tilted or in motion over the supposed target? Why were both mods switched in when the average Joe would demonstrate each individually? Why didn't he compare the ground cancelling ability over say a marked 20' section of ground? Why wasn't the same coil used on each detector? Why didn't he conduct a static field test?? Did you conduct a static field test on the modified 2000 which supposedly saw your infamous aluminium block deeper than any other model at your test site?

Common sense also tells us that the high frequency mod results in a proportionate large reduction in coil current so why doesn't woody advertise this along with the obvious fact that this leads to a reduction in sensitivity to nuggets already detectable with a stock model? Eg, if we double the frequency then we almost halve the peak coil current!!!! You knock ML but appear to condone this very misleading practice!

Really Doug, your obvious bias and lack of understanding makes you a very poor source of accurate information. You should at least try to keep abreast of new technology otherwise you will be simply seen as a stone age man trying to tell Einstein he got it all wrong and you should keep these discussions on your forum where a few actually believe some of this stuff.

The patent parrot.

[Qld Sandy]

Doug,

SETA has nothing to do with Ferrites. It is a truly novel way of cancelling static fields for a large number of timings without needing a bunch of cmos switches and trim pots and factory adjustments for each timing.

How do know this?Has Bruce told you? and what is this static field?Is it not the geomagnetic field at a particular location? Do soil/rock magnetic ferrites contribute to the local net geomagnetic fields?

In theory, the number of timings could be almost infinite. SETA requires a processor to work and this is much more complex than anything you have planned for the QED.

How do you know this? The QED could have thousands of timings as well and the MC can dynamically change the sampling windows, filters,Tx pulses length etc. In many ways the pic33h MC is far more versatile and in some aspects better than the DSP processor and micro in the 4500 (eg sample bit resolution) which if you did some reading (I doubt that you even know what the DSP processor in the 4500 is! ) would know.You know nothing about the QED other than what has been published on the forum which is just a drop in the ocean! I can say that we have some components in the QED that are far better than in the 4500, have SMR and are in the process of implementing digital filters in the MC firmware etc.Your comments on it are way off the markand just more of your rampant unfounded speculations!

If you have read and can understand the patent then you would also see that it would be very silly to allow anyone to perform mods on a 4500.

You are supposed to be an ex-scientist and yet you can't, or refuse to read the patents and jump to conclusions if it suits your obsessive anti Minelab agenda.

Why would I want to waste my time on ML patents?

Large coils warp more than small coils when they are abruptly tilted because of the much larger force exerted at the lugs, so you should at least check this before jumping to conclusions by removing the coil and tilting it by hand well away from the ground or metal objects, ensuring it is suitably supported and the cable can't influence the result. The trend towards making coils lighter can also make some coils more prone to flexing. Heck Doug some large coils require the operator to side step with the swing and use a slightly circular motion at the end of each swing!

So what! Just more excuses for the ML shortcomings!

Qld Sandy is correct re mildly conducting soils causing more problems for large monos and you will be faced with the same problems with the QED if you can first solve other generally unknown problems you will surely encounter.

What are other generally unknown problems? Just more of your unsubstantiated speculation is it not!!

I agree conductive soils are a problem for ANY PI but can be overcome (at the expense of loss of depth on some targets) by changing the corner frequencies of the bandpass filters or taking much later samples which we can do easily on the QED because the sampling windows are not fixed

You would actually know this if you had conducted tests or even seen JP's videos.

Yes I have some of Jp's videos but I have better things to do with my time than watch them!

The ground Sandy is talking about can be average ground found anywhere but is often worse in the diggings and lower slopes and gullies and in sink pockets. The latter usually sounds exactly like a symmetrical metal target. You can often pick this ground by the way the coil responds when tilted because a sensitive pi can't universally cancel the varying volume of mildly conducting material under the coil and still remain sensitive and is thus prone to changes in orientation and increased coil size. BTW, BW will eventually understand what is meant by universal cancellation if he is actually using a gain of 16,000,000 (cough) and he might even perhaps understand what he is seeing when looking at the Enhance timings oscillogram on your site.

I don't think you understanding what you are looking at either do you? You just think you do! ML cannot universally cancel all ground types as you well know! See what happens with any ML ( even the 4500 with SETA )when you vary coil standoff distance with a big mono at kingower or Beggary hill Vic or go over LIRM ground or higher than average remanance ground.

You say it is appalling that a viewer can't tell which coil is the best in your two oscillograms on the other thread but why would the average user be expected to know which is best, especially without knowing what he is looking at or if the damping is constant in each case? I could easily form an argument favouring the old coil Without more info and would also assume you have a circuit problem when looking at the newer coil's waveform. I bet BW had to explain the oscillograms to you so why dump them here without a thorough explanation?

No BW did not have to explain as all the parameters including the damping resistor were the same you dill!

You whinge about supposed problems with static field cancellation and yet you are very cautious in your comments re the video on this link.

The only detector actually shown sweeping across the ground when approaching a supposed target is the unmodified 3000 and the ground is obviously very quiet!!!! It appears to give a response on the first sweep and nothing thereafter, which suggests the target was a hot rock and it tracked out. If so then why didn't the modified detector track it out? I think I know after seeing what Woody does to the front end of these detectors! We never see the modified detector being swept over the ground when approaching a target and the operator has trouble developing the signal even though he supposedly found each target with this machine, and notice the excessive noise when the coil is tilted or in motion over the supposed target? Why were both mods switched in when the average Joe would demonstrate each individually? Why didn't he compare the ground cancelling ability over say a marked 20' section of ground? Why wasn't the same coil used on each detector? Why didn't he conduct a static field test??

I have made some of these same points myself and I have nothing to do with the mods or the testing. What I would say is that Woody and some other know far about the circuits of ML detectors than you!!!!

Did you conduct a static field test on the modified 2000 which supposedly saw your infamous aluminium block deeper than any other model at your test site?

The test was done with 2 modified sd2000's one was Woody's an one was one was somebody else WHO really knows ML detectors and has found a fortune in big nuggets in Vic. The test was done rigorously and has been repeated on other occasions and with other people with their 4000's, 4500's where the tester does not know if the block or a nugget is in the hole, The results were the same!

Common sense also tells us that the high frequency mod results in a proportionate large reduction in coil current so why doesn't woody advertise this along with the obvious fact that this leads to a reduction in sensitivity to nuggets already detectable with a stock model? Eg, if we double the frequency then we almost halve the peak coil current!!!! You knock ML but appear to condone this very misleading practice!

Again is this just more of your speculation?

Where have I condoned what Woody does? Why don't you tackle him with your concerns on GPOZ?

Really Doug, your obvious bias and lack of understanding makes you a very poor source of accurate information.

My god who is calling the kettle black. Your bias is obvious! You are just one of the ML moron hit men whose sole purpose is to discredit anybody or any technology that might produce a serious rival product to ML, is this not the case! Why not fess up?

You should at least try to keep abreast of new technology otherwise you will be simply seen as a stone age man trying to tell Einstein he got it all wrong and you should keep these discussions on your forum where a few actually believe some of this stuff.

What a joke this comment really is when your posts clearly show that you are not keeping abreast of technology like MC and DSP and all you can do is regurgitate the convoluted writings of your god and are blind to anything else!No wonder you won't show your face on GPOZ (you like to stick to safe forums like G@C) as not only are you a patent parrot but ultimately a forum coward as well! At least I have the balls to step into the lion den!

At least in my very small way I am trying to contribute something positive to help in the development of a more affordable/top performing MC Pi detector(as well as others) and running one of fastest growing detector forums on the web. What contribution are you making ,other than your inane and speculative prognostications and your efforts to discredit anybody or any technology that is not ML!

You are a time waster and a waste of time with your present attitude and I for one will no longer bother responding to you. There are none so blind as those that cannot see!!!!!

All the best.

Doug

ps

Don't forget to kiss the arse of your God!

Toadwhisperer,

You'll learn something as you sift through whats presented and ultimately make your own mind up. I brought up the scenario that a 4500 has trouble on some ground types as I have experienced it personally, and also found settings to be able to work the ground successfully. That doesn't mean I am a 4500 basher, as I believe it is by far the best offering that Minelab have put out and any future machine will have to be a beauty for me to want to change. Isn't that what it's all about - learning? Cheers.

ps circle what??

[Toad_Whisperer]

Toadwhisperer,

You'll learn something as you sift through whats presented and ultimately make your own mind up. I brought up the scenario that a 4500 has trouble on some ground types as I have experienced it personally, and also found settings to be able to work the ground successfully. That doesn't mean I am a 4500 basher, as I believe it is by far the best offering that Minelab have put out and any future machine will have to be a beauty for me to want to change. Isn't that what it's all about - learning? Cheers.

I had removed your name within a couple minutes of my initial post when I re-read what you had written, apologies for including you.

These personal battles between egos are getting old and goes beyond constructive debate, it's becoming childish and diminishes what credibility they may have had.

[Qld Sandy]

I had removed your name within a couple minutes of my initial post when I re-read what you had written, apologies for including you.

These personal battles between egos are getting old and goes beyond constructive debate, it's becoming childish and diminishes what credibility they may have had.

No worries. Forums are good for finding out things that you may never get to realise without them, and are also good for sharing thoughts and ideas. Forums are bad because there are some that push their agendas relentlessly. I have my parameters set already and I expect so do the majority of forum visitors. If I offend someone with my posts then I unreservedly apologise, but I would hope that I offer some alternative to consider without being totally and cyclopticly (is that a word - it is now) biased. Cheers.