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New Fisher PI - Rick’s Manifesto
Posted by: lytle78
Date: June 13, 2018 01:30PM
With Fisher completing development of Alexandre Tartar’s Manta beach PI and preparing it for market release, I thought the Technology forum would be another good place to ost the following. Alexandre’s work was the result of 10 years of study and further development of treasur hunting PI detectors. Having studied, rebuilt, modified and generally mucked about with Eric Poster’s key designs like the Aquastar and Gold Scan 5c, Alexandre and his team took the principles of these machines as a start and developed entirely new designs which expressed the key strengths of Eric’s work in new and more powerful ways.

I posted this a few minutes ago on another forum, in response to a question of whether a special purpose gold hunting beach PI like the Manta would be a machine that folks would buy and then not like.

I think the answer is some will love it, some won’t. Pretty much like any other detector. You build PI machines which a lot of folks have used and most really love, but they are clearly not for everyone.

Beach hunting is hard work and unless you live near the beach it is a thing you can only do when you infrequently travel to the beach. PI beach detectors have been on the market for decades. They are niche machines in beach detecting and beach machines are a niche within the overall detector market.

Fisher’s primary challenge is to produce a machine which is light and elegant and lives up to the picture painted by enthusiastic folks on the forums.Their next challenge is to present it correctly. I am pretty sure that they don’t want every hunter who goes to the beach to buy one. FT are busy developing new platforms which will address the challenge posed by the latest crop of “go anywhere” detectors - water resistant VLF’s with salt beach capability (mostly but not exclusively multifrequency).

If we look at existing PI water machines we see detectors with depth on low mineral beaches equal to or superior to machines like the Excal, CTX and CZ21 (on black sand or other mineralized beaches they clearly beat the VLF’s). The current machines lack any practical means of identifying iron. The result is that users often find that they end up digging more and deeper holes without increasing their finds. They also are no more sensitive to small gold than VLF’s which can operate in Salt. A lot of them end up being sold on or put in the closet, and the user either giving up beach detecting or reverting to a VLF. Some dedicated hunters, especially where mineralized beaches prevail continue to use them and get super results.

The new Fisher PI will be a specialized tool. It’s for gold, just like a Minelab GPZ which costs $7000. The difference is that finding an ounce of gold nuggets is really, really hard. Lots of folks try for a year to find their first tiny one. Head to the beach with a good beach detector and the odds of finding gold are nowhere so remote - and the gold you find is in bigger chunks than the average nugget hunter will ever find.

The Manta has two key characteristics which aim to make it a deadly gold hunter. First and most important, it claims to be more sensitive to ALL gold than any previous salt water detector. It does this by having an adjustable pulse delay control which goes down below 10 microseconds pulse delay - this has two effects, it enables finding smaller gold than any current detector in salt water and second Manta has more depth on all gold. All this sensitivity would be no good if weak target signals were swamped by circuit and ground noise. The Manta’s design has been refined and every design trade off made in the direction of extremely low noise, letting weak signal be heard.

So, folks might say - OK maybe it will find more gold, but PI’s also hear every tiny flake of metal and drive me nuts and wear me out digging deep holes for nails, hairpins and aluminum trash.

The feature of the Manta which has probably gotten the most attention is its ability to ID or eliminate ferrous targets. The iron ID/elimination capability of the Manta is based on the operation of its ground balance system. This function puts iron and high conductors into the excluded “bucket” (it has two modes, no return or multitone) and puts low conductors - gold jewelry and aluminum - into another “bucket”. The degree of operation of this feature is variable from “all metal” level through increasing amounts of rejection. Use of this will greatly reduce or eliminate digging ferrous junk. Unlike the primitive iron ID of the Minelab GPX machines, this feature works to nearly full detecting depth of the machine. Since it works on the strength of the return signal, vs. its phase shift, it will likely eliminate those dreaded smashed and ripped deep aluminum cans.

At high levels, the largest ferrous targets and other targets with high conductivity are rejected. With use of the ferrous rejection feature clad and silver coins are excluded. Not so great for “clad stabbing” The testing so far has concentrated on finding gold in the water and France doesn’t have recent high conductor coinage. The use of iron ID when silver is the target may work fine by adjusting the pulse delay to a higher value and choosing a lower level of iron exclusion, or it may be necessary to hunt in all metal with a high pulse delay value to eliminate small ferrous and all aluminum. In any event, LE JAG has reported that in his 3 years or so of testing and using successive Manta prototypes he has mainly operated in all metal - stating that most iron gives a double “blip” especially if the coil is lifted slightly. In this mode, silver and clad are detected, just like everything else.

Using the Manta for gold in salt will be just like any other beach machine in one way - the user will have to adapt control settings and search techniques to extract the maximum information from the ground and to make effective use of his time and energy. Fisher’s argument is that between the gold finding power of the Manta and it’s abilities to avoid digging ferrous junk, it will obsolete all previous PI beach machines and outperform any current beach machine of any type - tall order, we will see if it measures up.

The upcoming testing of pre-production machines here in North America will no doubt clearly reveal the best use of the machine’s capabilities - When that data is in, I’m pretty sure Fisher’s advertising and social media information on the PI will reflect its strengths and limitations. They are well aware this is not a mass-market machine. I suspect also that they are putting off setting a price target for this until they have a firmer grasp on the scope of its usefulness and appeal. The GPZ costs $7000 - why? - because it finds gold nuggets better than any other detector in the world and gold is valuable - Minelab charges a kind of tax on gold. If the Manta can demonstrate that it really finds gold jewelry in salt water better than any machine in the world it will totally dominate an admittedly niche market - fortunately, I doubt that Fisher is interested in “taxing gold” - so I’m sure the price will be much more reasonable.
__________________



Rick Kempf

Re: New Fisher PI - Rick’s Manifesto
Posted by: lucar
Date: July 05, 2018 01:24AM
Hello,

I have a three years old experience in searching the seabed in down to neck level deep water with a waterproof Whites TDI SL.

I'm skeptical about Your claims for the following reasons:

10us are not achievable in saltwater due to the saltwater itself response up to 15us or even 20us pulse delay, depending on water salinity and water column height.

I'm digging rings down to 38 cm in saltwater that is the maximum range of my modded TDI and that is also the maximum depth You want to dig a moving Target in the seafloor whatever scoop You have in Your hands. I'm already giving up digging 10% of my targets because of excessive depth and , sincerely, I don't need a detector that allows me to ear targets at 50cm, that would result in an embarrassing situation.

About Target discrimination, experience says that a dig all, dig everywhere approach is more rewarding than a "choosy" one.In my Excalibur infested areas I'm perfectly finding gold as if there was no one searching there and that to me means just one thing, that discrimination is not the way to go for serious gold hunting.

I perfectly understand that discrimination is a marketing thing in water detectors, people have just a few holidays time to spend in the water and they won't want to spend it digging cans or caps, so a discrimination circuit gives them the impression that they dug all the good targets fast and with the minimum effort, but in absolute terms, there is no substitute to a dig all method.

In one sentence , once Your maximum digging depth matches Your maximum detecting depth, You're done.

Luca

Re: New Fisher PI - Rick’s Manifesto
Posted by: Dave J.
Date: July 05, 2018 01:50AM
Quote
lucar
Hello,

I have a three years old experience in searching the seabed in down to neck level deep water with a waterproof Whites TDI SL.

I'm skeptical about Your claims for the following reasons:

10us are not achievable in saltwater due to the saltwater itself response up to 15us or even 20us pulse delay, depending on water salinity and water column height.

I'm digging rings down to 38 cm in saltwater that is the maximum range of my modded TDI and that is also the maximum depth You want to dig a moving Target in the seafloor whatever scoop You have in Your hands. I'm already giving up digging 10% of my targets because of excessive depth and , sincerely, I don't need a detector that allows me to ear targets at 50cm, that would result in an embarrassing situation.

About Target discrimination, experience says that a dig all, dig everywhere approach is more rewarding than a "choosy" one.In my Excalibur infested areas I'm perfectly finding gold as if there was no one searching there and that to me means just one thing, that discrimination is not the way to go for serious gold hunting.

I perfectly understand that discrimination is a marketing thing in water detectors, people have just a few holidays time to spend in the water and they won't want to spend it digging cans or caps, so a discrimination circuit gives them the impression that they dug all the good targets fast and with the minimum effort, but in absolute terms, there is no substitute to a dig all method.

In one sentence , once Your maximum digging depth matches Your maximum detecting depth, You're done.

Luca

Whatever the "ex-Manta Fisher PI" turns out to be, there'll be people who love it and people who don't. Just like with other metal detectors.

I'm not part of the "ex-Manta Fisher PI" project, haven't been involved in field testing it, and don't know the details of how they've achieved what they claim to have achieved. However I do know that it's technically possible to knock out the salt water at short delays. It's because I know it's technically possible, that I regard as credible their claim to have done so.

Re: New Fisher PI - Rick’s Manifesto
Posted by: lucar
Date: July 05, 2018 03:56AM
Quote
Dave J.



Whatever the "ex-Manta Fisher PI" turns out to be, there'll be people who love it and people who don't. Just like with other metal detectors.

I'm not part of the "ex-Manta Fisher PI" project, haven't been involved in field testing it, and don't know the details of how they've achieved what they claim to have achieved. However I do know that it's technically possible to knock out the salt water at short delays. It's because I know it's technically possible, that I regard as credible their claim to have done so.

Well, that's just my opinion, I might be totally wrong.

I also belive that if You go lower than the 15 or 20 uS limit, You'll get in to a nightmare of earing the thousands of metal fragments and tiny debrits that seawaves eroded out of the trash and that usually populate our beaches.
As a matter of fact , I did try the dual field coil and I had to swtch to a mono since I was constantly digging sub-millimmeter pieces of foil , rust etc. and all that in the 17us region, I can't immagine how worst that could be at 10us.

I hope I can test a Fisher PI sooner or later , since it's been in the rumors by the years ..

Luca

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Re: New Fisher PI - Rick’s Manifesto
Posted by: lytle78
Date: July 05, 2018 08:02AM
Luca, time will tell. Once it is available there will be lots of reports. The prototypes have been running successfully for more than 3 years at delays well below 10μS in running seawater. Carl Moreland of Fisher has reported on a Forum that he ran a prototype smoothly at 6.5μS delay in running seawater in Oregon. There is likely more to that ability than simply reducing the pulse delay. Very careful engineering and software design to reduce noise overall and clean up the return signal.

As you know, increasing volumes of salt water present an increased signal return and the minimum pulse delay of diving detectors is much longer. the Manta prototypes all had adjustable pulse delays and so can cope with deeper water or the desire to increase the delay in order to not react to tiny bits of aluminum trash, etc - if that is a problem in a particular location.



Rick Kempf

Re: New Fisher PI - Rick’s Manifesto
Posted by: cjc
Date: July 05, 2018 07:29PM
My two cents would be that for sure when you go down around 10 uSc, in salt--the noise created by waves is a big problem. I waterproofed a TDI Pro and was dissapointed by the performance in fast salt. It needs to be brought up to Dual Field range (16 - 17.5) range to be stable and still is not nearly as smooth. This could be a function of the coil (stock) and there are likely other factors at play but the GQA2 is about the same--even with an adjustable SAT it still needs to be run up arond 12 or higher in salt. I really hope that Alexandre's machine does funtion on that level but from what i've seen there are always trade-offs.
cjc

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Re: New Fisher PI - Rick’s Manifesto
Posted by: lytle78
Date: July 05, 2018 08:45PM
Alexandre and his friends have spent 10nuears quietly improving on what Eric Fisher gave us. According to Carl Moreland of FT and LE JAG - the chief field tester, serious development, design and care have scored a real advancement in overall performance. The re is, however no need to believe that my conclusions are correct. Soon (but not soon enough for some) machines will be for sale. Experienced sea gold hunters will snap them up - afraid to be behind the power curve.

Then we will begin to see sober reports as to whether this is re olitionary, or just OK, or a flash in the pan.

I know I will be early out with one - first chance I get.



Rick Kempf

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Re: New Fisher PI - Rick’s Manifesto
Posted by: LE.JAG
Date: July 06, 2018 01:06PM
Hello,

we have not done any diving tests yet
at great depth / wait sealed boxes
do not delay, being assembled ..

you base your impressions on machines that generates a lot of noise
the Fisher will be quieter than you've ever had



Quote
lucar

In one sentence , once Your maximum digging depth matches Your maximum detecting depth, You're done.

Luca

again it's a mistake
your maximum depth is defined by the size of the target

with a more sensitive machine you will have lighter targets
at this same depth

so: it's not over
there is still a lot of gold that has escaped you
for the moment :beers:



Fischer--Aquamanta // Pulsepowers Goldscan 5C // Nexus coronado // Vista Gold

( sorry for my english )

Re: New Fisher PI - Rick’s Manifesto
Posted by: daverave
Date: July 10, 2018 04:10PM
my tdi will work at 8 uS delay with modified coil,,,,and on the wet sand its impossible to use this low delay without ground effect...yes on the dry sand no problem but wet sand is another story...i use a 14" mono coil and i can detect my 9ct 3g wedding band at around 20" in air which i feel is good depth....if the manta can detect very thin gold chains in wet sand without any ground effect then i think that will be impressive.



Edited 2 time(s). Last edit at 07/10/2018 04:36PM by daverave.

Minelab charges a kind of tax on gold? nonsense from your side
Posted by: kt315
Date: July 11, 2018 04:42AM
Minelab charges a kind of tax on gold -- just only he is greedlab. i give to this world free projects - Delta Pulse, Barracuda, Tesoro royal sabre.
no tax on gold. we and american people are no so rich to pay greedlab tax.

Re: New Fisher PI - Rick’s Manifesto
Posted by: markg
Date: July 29, 2018 08:03AM
I'd like to add one thing. If the Manta is finally released and it has a "filter" to help with nails and still allow silver coins to be heard I'm in. I did the following video with a gold ring and nails and I can make my TDI emulate the Manta in this regard. Some of these techies say discrimination on a PI can't be done but many years ago people believed we would never go to the moon. See what happened years later? And by the way I still have and use the TDI in specialty areas.


https://www.youtube.com/watch?v=tz2PEunAtec

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Re: New Fisher PI - Rick’s Manifesto
Posted by: lytle78
Date: October 18, 2018 04:53PM
Sorry, Manta is for gold, not silver

Today’s prices - silver $14.65 - gold $1228.

I know which one I want.

No detector in history has consistently found more gold jewelry per hour at beaches than Eric Foster’s Aquastar. Manta is Aquastar on steroids. Same basic concept - refined through thousands and thousands of hours of work by a very bright team of European engineers - now part of Fisher.



Rick Kempf

Re: New Fisher PI - Rick’s Manifesto
Posted by: Bleaver
Date: November 12, 2018 10:11AM
10us are not achievable in saltwater due to the saltwater itself response up to 15us or even 20us pulse delay, depending on water salinity and water column height.

I have found this to be an issue on a number of PI's. The Fisher Impulse PI (1990's) could no adjust to differences in water height, so was not very usable in surf.
I found the same problem with the Whites Dual Field.
FOR ME - they were best on shore lines.

Hopefully the new Fisher will have some autotune or some way to accommodate changing water height. The other item that would be a real plus is if the Coil profile is thin enough to slide easily through the water. The old Whiter Surfmaster PI and Tesoro Sandshark come to mind for ease of movement through the water.



LAND (3): Silver Sabre uMax 3D (2ea), Tesoro Vaquero 3D
WATER (3): Fisher CZ-21 (2ea) , Tesoro Sandshark;

Mississippi


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Re: New Fisher PI - Rick’s Manifesto
Posted by: lytle78
Date: November 12, 2018 11:59AM
Bleacher, Carl Moreland - Chief Engineer has posted that Manta prototypes have run happily at 6.5 microseconds in Oregon surf. Here’s what he posted on another forum...

I've taken the Manta out on Oregon beaches at 6.5us, with surf running over the coil. Surprisingly stable. Yes, if you pump the coil up & down a lot you will hear the salt, but with a normal swing very little salt noise.

The ability of PI’s to run at shorter pulse delays in salt water than previously though possible turns out to be a function of careful electronic design and coil design/construction.

It is of course true that as the volume of salt water seen by the detector increases, the minimum usable pulse delay increases.



Rick Kempf

Re: New Fisher PI - Rick’s Manifesto
Posted by: Bleaver
Date: November 12, 2018 07:47PM
I hope your right, but from your quote from Carl Moreland, I didn't get the sense that he was talking about water hunting with 1 to 4 feet of water over the coil and constantly changing. It would be great it that's what he meant.



LAND (3): Silver Sabre uMax 3D (2ea), Tesoro Vaquero 3D
WATER (3): Fisher CZ-21 (2ea) , Tesoro Sandshark;

Mississippi


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