PI detector general usage

[Ratas de la Jungla]

Do PI detectors have any useful purpose aside from beach detecting? An acquaintance has a Tesoro sand shark that’s been sitting and I could get it st a great price, but beach detecting just isn’t my thing... I think it’s almost too good of a deal to pass up. I could always just flip it and make a few bucks, but don’t need the hassle... I do some relic hunting and have a T2 which seems to be a fairly hot unit when I compare it to some others I have been around, and I have a Ford CoRe. I have limited Comms so I can’t research the topic. What do you all think? Snag it or
Let it pass.

 

[vlad]

PI's ability to discriminate or identify iron is primitive at the least and almost non existent at worse. Amount of iron trash should be a consideration.
They can hit iron so small (and gold nuggets) they are difficult to see; some units can differentiate between high and low conductors too like the Whites TDi and some by Garrett.
And on some models that can identify iron (tonal) that ability is limited to how deeply they can do this.
But if you are hunting in really bad ground no VLF can equal the PI depth.
What type of relics are you looking for (many things fall in this general category.)

 

[Dancer]

I hunt a Garrett Infinium L/S. It has two tones which with use can be fairly accurate while hunting the mud. But you gotta have the right conditions. I hunt coins / Jewelry. So I use it in open relatively non trashy areas. It has increased my fines in deeper ground. But hunting a Pi in iron infested ground, well not the best choice.

 

[Tom_in_CA]

... some units can differentiate between high and low conductors too like the Whites TDi ...

But by the time you implement those control options to do that, your depth is cut-to-the-point where you are getting no more depth than standard discriminating power-house machines of today. So .... what's the point? If a person wants the fabled depth of pulse on the TDI, they have to forgo the trick option you're speaking of.

 

[Mega]

... some units can differentiate between high and low conductors too like the Whites TDi ...

But by the time you implement those control options to do that, your depth is cut-to-the-point where you are getting no more depth than standard discriminating power-house machines of today. So .... what's the point? If a person wants the fabled depth of pulse on the TDI, they have to forgo the trick option you're speaking of.

For the most part i totally agree with you,but i have access to a roman trading villa site that has been active for 400 years,what is weird about this site is the fact the ground is so high mineral content that it looks like black sand,but its possibly 70-80 miles inland well away from the coast.Multi freq machine can work of a fashion but the best machines for this specific site is the GPX and TDI range of machines which do have these rudimentary discrimination facility,but they do work well and basically are in my opinion the best tools for the job.

Raw depth is not necessary a high priority on this one specific site,but the ability too cut through the high mineral content is a major priority and being used for 4 centuries of course one also has trashy and hob nail boots,this one site over the last 10 years has produced 1000s of roman coins,and still very prolific.So i do agree with you but some situations the ability on using these features in the case of the TDI high/low conductivity is a good feature to have.

But on hoard.artifact sites like on clear pasture then yes running it in pure PI mode is the way forward especially when using a large coil.

 

[Tom_in_CA]

Ha, this crossed my mind as I made the post. Because back when the TDI first came out, we had taken it out to test it. And we made the observation that ... IN ORDER TO AVAIL ONESELF of the high vs low conductor differentiation, that you therefore lost the fabled depth. However, I distinctly recall wondering if whether: While this is true, yet it might accomplish this in nasty grounds that the standard discriminators don't have access to ?

So while what I was saying was true for 95% of all ground on earth, yet there's perhaps certain particular environments where a person HAS NO CHOICE but to use a pulse machine (because of nasty minerals). Well gee, then in those cases, I suppose you're better off having a pulse that *at least* has a fighting chance to tell iron vs non-iron. And *at least* has a fighting chance to tell lows vs highs. EVEN IF THAT LOWERS YOUR DEPTH, well .... at least it's a spot that your standard machine might have been shut down at.

Yes I considered this possibility. But it represents sseeooo few areas that I'm likely to ever run into, that it became a point of non-consideration . Besides: The TDI is sseeoo squirrely to operate for coin-hunting in the first place. Just too dang sensitive to cr*p that a person DOESN'T want to find (teeensy boot nails, etc....). But .... that's just me.

Good post Mega !

 

[Ratas de la Jungla]

Just curious as to the maximum depth that could be expected under normal
Conditions... if there is such a thing

 

[Tom_in_CA]

Just curious as to the maximum depth that could be expected under normal
Conditions... if there is such a thing

For what machine ? You mean the TDI ? And if so, under what criteria ? : Ability to retain semblence of TID for iron ? Ability to tell highs vs lows ? Or .... utterly no ability to differentiate whatsoever ? Also: You're not saying the size of the object you have in mind. Eg.: pinhead nuggets ? coins ? gold bars ? Volkswagons ? etc....

 

[vlad]

without using the ground balance on the TDi? I have read of a few folks that built Eric's 'Afterburner' which was said to make it.......hot (ter.)
I've been to some places like Central Tenn where the negative ground was so bad VLF's had little depth; and East Texas with red clay and iron ore that was a
magnitude worse. My Foster PI the PPD1 (non grd-balance) worked well but even it was affected.
Eric knew about the negative ground effect and its why he added a ground balance. I got one of 2, Goldscan 1 prototypes (non-motion) for test in the US and it worked great- it had a mode for low conductors only also. But if I were hunting iron projectiles---ground balance was not used. Specific units for specific tasks. (The late Tom Dickey used my PPD1 for projectiles in salt zones where the VLF's just did not do well--especially for iron wrapped in a thick mineral cocoon-in wet salt.) Eric even said it was easy to make an orthongal loop configuration for a PI--a projectile hunter's dream. But a waste for a coin hunter.
So, what's your favorite 'vice'?

 

[Tom_in_CA]

I'm not so sure I'd want a TDI that was "hotter". Unless I was looking for nuggets, or pushpins at extreme depths.

No, I have not heard of any after-market addition that would allow it to tell high vs low, or iron vs non-iron, w/o loosing depth. It's just too squirrely sensitive as-it-is for land hunting.

I could see using it for nice clean beaches. But ... no ... not land sites.

There was a fellow using one here on a beach storm erosion spot that was riddled with nails. And he could indeed pass some nails.. But .... the guy was going bonkers on a lot of days (required a *lot* of patience, and setting there studying all sorts of sounds). The next year, he was on the beach swinging a standard discriminator like the rest of us :/

 

[vlad]

Reg has developed a mod--some time back, no ground balance need to i.d.

 

[doc holiday232]

without using the ground balance on the TDi? I have read of a few folks that built Eric's 'Afterburner' which was said to make it.......hot (ter.)
I've been to some places like Central Tenn where the negative ground was so bad VLF's had little depth; and East Texas with red clay and iron ore that was a
magnitude worse. My Foster PI the PPD1 (non grd-balance) worked well but even it was affected.
Eric knew about the negative ground effect and its why he added a ground balance. I got one of 2, Goldscan 1 prototypes (non-motion) for test in the US and it worked great- it had a mode for low conductors only also. But if I were hunting iron projectiles---ground balance was not used. Specific units for specific tasks. (The late Tom Dickey used my PPD1 for projectiles in salt zones where the VLF's just did not do well--especially for iron wrapped in a thick mineral cocoon-in wet salt.) Eric even said it was easy to make an orthongal loop configuration for a PI--a projectile hunter's dream. But a waste for a coin hunter.
So, what's your favorite 'vice'?

Vlad do you know if Eric ever made any orthongal loops? Esp. for the TDI Pro?

 

[vlad]

n/t

 

[Ratas de la Jungla]

well io thought i could use it to locate buried electrical cables or maybe even some kind of deep relics, and don't have a waterproof machine... doesn't matter. the guy showed up... unwrapped a new package of batteries, and the battery holder shorted out and kinda melted... seemed like a deal if i could have found a use for it. I do SCUBA, but mostly just spearfishing and photography, and its been a while since I did that sorta thing, the beaches here aren't great and they get hunted regularly by the locals... it seems... Spent the $$$ on a NEL Snake, Sharpshooter, and Storm coils for my T2 instead, got all three for $290... probably a better deal in the long run.