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9 hours ago, kac said:

.... you can sort of tell iron from non iron as the signal is a bit louder and slightly different ...

Here is where the devil is in the details, if you ask me .  

 

I have heard many many pulse users say such a thing.  That they can tell the nails (yes, even bent ones) by a "slightly different sound", blah blah.    But when we see these guys show up on nail-riddled beaches, they last all of 20 minutes.  And then we have the beach all to ourselves again   😕

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GBA, I couldn't help it... spent most of the day thinking about it, and decided to spend the waning hour and a half of daylight at my old school ground with the ATX.  Only I can fully appreciate the p

GB :  I know there are some coin/relic guys who will try to use those balls-to-the-walls pulse machines , for coins/relics.  Since, sure, you can "get a coin to 1.5 ft. deep", blah blah.  I saw a few

I'm not sure if this is the same reaction other PI's get, but on my GPX, coins hit louder and narrower than big nails do. Nails, for me, sound longer, and coins hit faster if that makes sense.  Coins

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27 minutes ago, Tiftaaft said:

There was an incredible post by Tom D. on his site years back, talking about clearing a turf site with a pi machine, and his finds... it was fascinating and worth a read if you haven't already.

I assume you're referring to this article.  Yes, it's eye opening (and fascinating) and I read it every year or so.  Besides Steve H.'s article on the TDI coin settings it's another reason I've wanted to try a PI in a site like this one.

I'm going to cover the area with the ML Equinox with 12"x15" coil before resorting to attempting anything with the TDI.  Lots of good responses to my request and there seems to be a consensus that a TDI is no panacea in these situations.  But I also want to at least experiment with it after I've made a good search with the Equinox.

Thanks for all the thoughtful responses.

 

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Just now, GB_Amateur said:

I assume you're referring to this article.

Yep - that's the one, changed the way I look at detecting for sure.

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Larger coils can be counter productive if you have upper layers of trash as you hear what is on top predominately. Higher trash areas the smaller or eliptical coils may help you sneak around the trash and pick out targets between better. When you swing over areas and hear nothing at all then maybe a pi or larger coil may sqweek out something that might be deeper.

The area really depends on what kind of activity was there over time. As an example yesterday there was a small hill where I picked up a reale few years back and picked up an Indian Head but at the bottom of the hill is a trash line with cans going down to 12"+. Soil on the hill is sanded and natural with a thin top soil line and bottom is dark black dirt with lot of modern trash. Bottom of the hill was filled in and whole field was just fill to cover a swampy area for farming. Bottom of the hill was wetlands at one time so there is no old stuff reletively speaking unless your a Millenial 🙂

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7 minutes ago, kac said:

no old stuff reletively speaking unless your a Millenial 🙂

haha.  nice KAC!

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Hello GB,

My main detector for parks is the TDI. I will list the settings I use and why I use them. With these settings I only listen for the deeper targets ( 5”or deeper) and the TDI will respond to deeper targets with a not as strong audio response. The surface targets or near surface will give a very strong audio response and the deeper targets will give a weaker response. Using this technique you can ignore many trash targets and concentrate on deeper targets. These settings completely ignore bottle caps, pull tabs and foil no matter what depth they may be at. Nails and wire will give a good response, but keep in mind I’m only listening for the deeper target so I’m digging less trash targets. People using the Equinox in are area can achieve some targets at the depths we are getting, but the are listening for deep target response with a scratchy audio. Our soil is highly mineralized and VLF detectors are limited on depth. I was fortunate to live close by Reg Sniff and he was able to give me advice on what settings to use. It will take awhile to become proficient with the TDI, but after a lot of hours you will have a better understanding of it.

Settings:

Sensitivity- Set at Max.

Delay- 10

Ground Balance- Just below the 5 mark.

Threshold- Light

High Conductor Setting

Frequency- Set at 12:00 o’clock.

I’m using the 12” Dual Field coil, but you definitely need a pin pointer as their is no meter or way of telling depth other than by sound.

I would not use the TDI in a ghost town setting that has a abundance of nails or any other areas that have a abundance of nails, but any other common trash items even with a large coil is not an issue. But you have to go slow and be patience and listen for the deeper targets.

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20 hours ago, Glenn in CO said:

 

My main detector for parks is the TDI. I will list the settings I use and why I use them. With these settings I

Glenn,

It's no secret that the TDI can be made to ID nails (down to a certain depth anyhow), and also discern high vs low conductors.  HOWEVER :  The moment anyone goes to avail himself of these settings-tricks, is the moment that his depth is now reduced to that of normal standard machines.   Right ?

When I toyed with the TDI,  I chose a particular school yard where I knew that some more deep wheatie/silver type signals existed.  I went out and flagged some suspected deep wheat/silver type signals with my Exp. II.   And then proceeded with all the "tricks" on the TDI, over these flagged signals.   And also over nearby flagged *obvious* foil, tabs, iron, etc... which I also flagged and tested with both machines and settings.  Mind you :  With my Exp. II, I can generally, reliably, get 8 or even up to 9" on a penny/dime type object (in this particular turf that's not too junky).

I came away with the conclusion that the moment I set the TDI to work like a normal discriminating machine (cherry picking for deep silver) is the moment that I might as well use a standard machine.   Not to mention the fact that the TDI is a SQUIRRELLY son of a gun.  Very annoying fishy audio.  

So do tell:  In your opinion, do you think that you can spank the user of a normal standard machine, with your TDI, in regular park-turf hunting ?  If the objective is deeper older coins (and not simply strip-mining clad, blah blah) ?

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Anyone just try to find the deepest target regardless of type in a given area?

Deep target hunting I use any of my machines with all metal mode and listen for the faint signals. Probably very similar to Glenn with the TDI. I do run into trouble with trashy spots where discrimination is needed.

Back to the TDI, the SL version may only hit depths similar to the Nox in average soil but will do well in very mineralized soil. I have heard the ATX can hit a silver dime at 12" or so and that could be similar to the TDI pro?

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46 minutes ago, Tom_in_CA said:

Glenn,

 

It's no secret that the TDI can be made to ID nails (down to a certain depth anyhow), and also discern high vs low conductors.  HOWEVER :  The moment anyone goes to avail himself of these settings-tricks, is the moment that his depth is now reduced to that of normal standard machines.   Right ?

 Tom in my area the answer is no. I and my friend who uses a TDI Pro get a clear audio response where someone using a Equinox or CTX3030 get a iffy or no response.

 

54 minutes ago, Tom_in_CA said:

I came away with the conclusion that the moment I set the TDI to work like a normal discriminating machine (cherry picking for deep silver) is the moment that I might as well use a standard machine.   Not to mention the fact that the TDI is a SQUIRRELLY son of a gun.  Very annoying fishy audio.  

My TDI is very stable in Ground Balance mode, Ground Balance mode off is very annoying.

 

59 minutes ago, Tom_in_CA said:

 

So do tell:  In your opinion, do you think that you can spank the user of a normal standard machine, with your TDI, in regular park-turf hunting ?  If the objective is deeper older coins (and not simply strip-mining clad, blah blah) ?

Yep and a lot of my detecting friends that got spanked!

My TDI was modified as well as my friend’s TDI Pro was modified by Reg Sniff.

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52 minutes ago, Glenn in CO said:

 Tom in my area the answer is no. I and my friend who uses a TDI Pro get a clear audio response where someone using a Equinox or CTX3030 get a iffy or no response.

 

My TDI is very stable in Ground Balance mode, Ground Balance mode off is very annoying.

 

Yep and a lot of my detecting friends that got spanked!

My TDI was modified as well as my friend’s TDI Pro was modified by Reg Sniff.

Thanx for answering all that.   If you ever make your way out to CA, I would LOVE to do some side-by-side flag-testing. 

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  • Steve Herschbach changed the title to Pi ( TDI ) Coin Detecting Advice Request

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