P I Machines (advice please)

[Radnor Bandit (Ian)]

Thinking of getting 1 but apart from knowing the basics that they pulse rather than motion etc and registers all metals. How do they perform on Iron pan, Do they ignore it or see it as a ferrous object. and approx what are good rule of thumb depths achieved ? And lastly WHICH one.
Cheers Ian

[U.K. Brian]

Could do with a little more information Ian.

As you mention iron pan does this mean you will be using on land or beach ?  Some will cover both areas but you should have a ground balancing model for land use.

There's lots of hype about depths that can be acheived. I will take my pulse detectors over twin/multifrequency 95% of the time on the beach but land is a very different matter. I went to the U.S. to try out the Whites TDI before it came out in this country and found that on the majority of land sites a detector such as a Tejon with matched coil size outpaced the TDI whilst still rejecting small iron. Extreme mineralisation areas were the exception but most Americans will not accept that we have extreme conditions over here.

I've used the Garrett Infinium (hated it), the other Garrett pulses  (Sea Hunters) with discreet discrimination (so discreet you can't find it !) Whites TDI and Surfmaster , Minelab, Deepers 6, Lorenz, Pulse Star II, Fisher Impulse, J.W. Fisher's, C-Scope's, Skladak (Polish), Notsi (Bulgarian) , Tesoro, Headhunter and a few others I can't remember at the moment.

For hoard hunters the Germans turn out perhaps the best quality product but you pay through the nose. Bulgaria has a range that were iffy on build quality but they improve year on year and are a fraction of the price.
The big improvement here is that while they were deep on large items, and even offered a degree of iron rejection on ferrous, fist size or bigger, they did not perform that well on rings/coins even with a small coil fitted. This has changed in recent years but you still would not really want to detect for small items with a hoard hunter.

My own Pulse machines are all Eric Foster designs (the King of Pulse). Beachscan (light/cheap), Goldquest SS and Deepstar (most expensive and chest mount as the battery is the size of half a brick).
He also designed for other companies such as C-Scope.

Most P.I.'s are now motion but several are not. There's advantages to both types.

You can't even really have a machine recommended to you because of modifications made over the years. The Whites Surfmaster is typical. First version had sufficient room to have a bigger battery holder inserted to take an extra two batteries if rechargables were to be used. Then Whites altered the case and the larger holder would not fit so for best performance quality alkalines were needed.
Some years went by and Mr.Bill (Bill Crabtree) in the U.S. started to tweak/modify both Whites Classics and the Surfmaster. Not to expensive and really worth having done.People would buy secondhand and have him do the mods or go for the new on the market Headhunter P.I.

Whites twigged they were losing business and came out with ....the Pro version. They removed the pulse delay and fitted a gain control. Now you could air test better but made the detector unstable in various hunting conditions so not the best move.

Meanwhile Headhunters, both VLF and pulse, were having problems due to mechanical damage of the headphones which hold the batteries and circuit board. They were pretty quick off the mark and improved the design but there's still a few years production out there thats the old design.

Of the Whites v Headhunters one is deeper and has better iron rejection (audio) but poor pinpointing, the other you can wade with happily as its fully waterproof.

The same applies to all brands mentioned. There's pros and cons. The Fisher Impulse is waterproof and deep but needs three hands to use it plus you can't have it repaired by the new Fisher group. A  J.W.Fisher can be repaired but is very limited in application as its a high uS machine to cope with the volume of water above the coil which is what you need for a diving machine whilst on land/beach/wading you require a low uS to provide sensitivity to rings/small coins.

Anyway before everyone dies of Pulse induced boredom, give a clue as to the use you want to use the machine for.
 
Re iron pan. Can be exactly like trying to detect through a sheet of metal though if its a weak iron pan/or scattered small iron the pulse does have a big plus in that it doesn't suffer ferrous "halo effect" to the same degree as VLF's, TR's. I.B.'s etc . In some areas you can get better performance with a good VLF used in all metal mode. You want to try VLF all metal as a first move before buying a pulse to see if you can stick the extra ferrous you will be digging. It can be quite an eye opener !

[Radnor Bandit (Ian)]

Thank you Brian for this reply, When I mean iron pan (as you can see from the photo), I am referring to inland sites, My main question is how would a P I machine react to this ground, Would it register the larger concentrations of iron stain as an object (as my EXP II does) or see through it. The main task I am trying to achieve is not extra depth but better separation of targets.
For instance when using my minelab, ( which I leave in all metal 95% of the time, I prefer to hear the iron so I can slow sweep to double check no adjacent targets) A target such as 1d ,on clean ground would be detectable clearly up to 12" (good 2 way signal) but under the above conditions due to background ferrous interference I have had a very iffy signal at 4".( Obviously under these conditions the sens would be backed off as much as possible.)
Am i asking for the improbable

[mole]

Personally myself this is my own opinion  I would,nt advocate the use of a pi machine in such ferrous contaminated conditions this would be something akin to walking into a scrapyard with your detector they just love Iron the explorer 11 as a a slow recovery speed normally  but in amongst so much Iron your losing more than you,ll find the route to go down would be a single frequencey machine with a faster recovery speed in your condition dept does,nt come into the equasionthe ability to find amongst ferrous saturation does you,ll be suprised what the explorer can miss in these conditions good hunting ;)mole

[U.K. Brian]

That's like my ground at 12 inches or so and I doubt you would get any penetration with the machines on the market at the moment.

If it was a light "stain" where your Minelab and other VLF's/BBS etc still treated it as a large sheet target a P.I. might well penetrate through on the same basis that they don't pick up iron "halo" and many are insensitive to silver foil. Basically pulse likes a lump of metal to respond to.
The pulse coil is an antenna that transmits the pulse then switches off. The pulse excites the buried item (just like you striking a bell) and the signal bounces back up to the coil which is now in its listening state. A nice thick iron/brass/alloy bell will give a long "ring" which the detector can pick up whilst a bell made of a thin metal would not provide a sufficient response.

Your asking the impossible in a way because the insensitivity that allowed old type P.I.'s to ignore foil on the beach or small iron on land meant they were not to good on fine gold/silver rings or hammered coins. They worked round that by reducing the uS settings of modern detectors from 30 odd down to 15 uS which boosted sensitivity up but reduced the inbuilt discrimination of the pulse principle.

[Radnor Bandit (Ian)]

Thank you, Brian an Mole, your answers have saved me a few quid. I was curious to see what machine may give me a bit more advantage on this and similar sites .But it looks like PI might not be my best route.
The photo shows flints found during 2 outings to the site, All within 100 sq metre area, So obviously I was wondering what else is there .

[hedgehog]

Some fantastic info there off Mole and Brian, and some nice flint finds there bandit!

[16.5DD (richard)]

yes pi's are built for the purpose of finding all metal (except stainless steel) don't like it...
well get an xp gold max power !!!
fast as lightening through iron  not much beats them unless you can xray the floor.
slight loss in depth but fast response may loose 1 inch or so on small hammered coin in comparison to exp2.
try a mates xp first and see

[Radnor Bandit (Ian)]

Ive got a GMP but cant get on with it , I bought it specifically for use on this and another flint scatter site I have discovered.(previously unrecorded)both of the sites have flint ranging from Mesolithic to Bronze Age.This shows continuity of occupation for millennia,Then there is a big gap in the finds and then the next datable finds are 16/17THC pottery. Curiously the only detector finds of the site (including adjoining fields) were a couple of Georgian 1/2ds.(and cartridges and cores).
   Whether it is me or the local conditions, Even when run in auto it still loves coke and iron, and the v4 chip audio is definitely iffy on mid and high tone. My hearing isn't great but its not that bad either. I have even tried several different phones but no difference. I wonder about build quality on XP (based solely on the flimsy corded back-phones supplied with machine) and maybe I have a Friday night model.
Also though a single frequency machine, even if the iron isn't registering what physical effect does this have on electromagnetic field ? does it cause a shift in the receive analysis circuit? Therefore confusing discrimination.
Or is this a bad case of there is nothing there to find anyway !