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  One time  I got more silvers then my 2 buddies did with their Explorers in a penny filled   picnic ground with  the Infinium. The low high hits were mostly silvers and  the wheaties  ran mostly high low  here so   I could cherry pick the silvers. Also there were not many nails.At one of my beaches that is hotter I would  get  deeper coins then the explorer even though  I     was getting a lot of nails with the pi.A PI in the right place can do the job. You have to know when to pick your spots.

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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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3 hours ago, Tom_in_CA said:

Or did you mean "successful" as in deep old silver ?  If so, I know of no one in CA who is "successful with the TDI" for that.  If you know who this fellow is, I would love to meet and compare over flagged signals with him.

I couldn't think of his name of the top of my head, so I did a little research and his name is Greg Moscini. He operated Trans Bay Metal Detectors, I believe in the San Francisco bay area and not sure if he is still in business.

Greg published the following in the White's TDI Manual:


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On 4/11/2021 at 10:44 AM, GB_Amateur said:

I've been experiencing lower yields due to sites being detected, by me for sure and there are also signs by others previously.  SchoolofHardNox's success on a beach using the Minelab GPX 5000 reminded me to re-read Steve's treatise on using the (in his case original big box Pulsescan) TDI for coin detecting.

I just a few days ago stumbled upon a promising site where extra depth could be key.  It's a schoolyard going back at least to 1955.  Unfortunately as is the case in many of my public sites, it has a history of backfilling.  From aerial photos I see than in the 50's it was grass/sod covered but in the early 60's they put down gravel.  The person who told me about the site (a person who walked up to talk when he saw me hunting a nearby park) said he was a student there 45-50 years ago and at that time it was (again) grass/sod.  I did a one hour survey hunt with the Minelab Equinox (11" coil) and encountered a couple inch thick gravel layer about 5" down.  I did find one Wheatie below the gravel, but 7" is getting deep for my detector + soil mineralization combination so if coins remain from the 50's (pre- gravel layering) then I expect I will do better with extra depth (and that may even be required).

One thing I've found in my detecting of these older sites -- there are always nails present.  So even if my TDI/SPP can deliver in the coin category it's going to be signalling on a lot of nails.  One of the tricks Steve used was to set the conductivity switch to high conductors (low tones) but the TDI/SPP doesn't have that feature -- I will be hearing both high and low tones.  This is a dual disadvantage -- extra tones to have to mentally tune out but also extra threshold noise since both parts of the signal spectrum will be contributing to that as compared to only half when the conductivity-low switch selection is made (on all TDI's except the SPP version).

Here are some specific concerns:

1) Am I fooling myself thinking I can get extra depth with the TDI/SPP, particularly when it comes at the expense of a noisier threshold?

2) Which coil(s) should I be using (choices I'm considering are 6"x8" Nugget Finder Sadie mono, 7"x14" NF mono, and 12" round White's 'Aussie' mono)?

3) Should I flag the promising targets but double check with the Eqx 800 (and if so, should I use the 11" or 12"x15" coil on the 800)?  (Note, even if I choose this route I will likely at first dig, regardless of what the 800 says, just to get an idea of what is giving the signal and how deep the targets are.)

Any other advice (from anyone) is appreciated.




GBA, Just curious... what would you consider a success at this promising site at the end of a day's hunting?  ~Tim.

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1 hour ago, Tiftaaft said:

Just curious... what would you consider a success at this promising site at the end of a day's hunting?

My goals are modest given my sites.  3-4 hour hunt:  satisfatory is 1 Wheat; good is one 'other old coin' (any silver coin, any Indian Head Penny, or a nickel earlier than Jefferson).  A semi-key Jefferson or Wheatie also turns a day to 'good'.  Excellent day is more than one of the above 'other old coins'.  A key date+mm Jefferson (38-S, 39-D, 50-D, 55-plain for me) or any of several scarce to rare Lincolns (e.g. -S mint prior to 1916), a silver half dollar, silver prior to the Barbers,... would be great days but I've never had any of those, yet.

Only a couple of my public sites were occupied/frequented prior to ~1955 which limits the potential finds.  I typically avoid any site which was unoccupied prior to early 1960's since the chances of older coins (including silver) drops off significantly.  But sometimes I can be fooled determining the age of a site.

I don't lust after jewelry or relics but a silver ring, which seem to show up occasionally, qualifies as satisfactory and a gold ring (I almost never get those since I try to avoid pulltabs, foil, and can slaw) qualifies as excellent.

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Thanks for sharing GBA, we sound very similar, though your expertise in numismatics is light years from mine. 

Wishing you a few excellent days and at least one great day at this site when you are able to get out and hunt it.   👍

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20 hours ago, Glenn in CO said:

I couldn't think of his name of the top of my head, so I did a little research and his name is Greg Moscini. ....


Greg M. will NOT be able to use a TDI, or any pulse, and pull more old coins from park-turf-hunting.  I have dueled with him before.   He's a nice guy, and a known reputable dealer.  But no .... he would not be able to use a pulse to out-do a standard machine in the turf , with anyone who is of an on-par level.


If someone wanted to compare machines with him, they would need to be *very careful* on stating what "successful" means, ahead of time.   To me, it means:  most old coins .  But if someone wants to lower his disc. and strip-mine, and gets on a V-nickel or something, that the other guy (who was cherry-picking) would have passed, then.... that needs to be stated ahead of time.   So that BOTH of them can lower their disc. 


If my desire were for gold rings, then I wouldn't be strip-mining junky urban turfed parks. I'd simply go to the beach.  


I know that some people think that by entering into a 'strip-mine' mindset, that they'll have the "best of all worlds".  But it never works like that for junky urban turfed park hunting.  At the end of the day, the person who was strip-mining will have a pouch full of junk, clad, a possible wheatie or two, and a .... yes ..... V nickel.   Because he spent all his time digging non-old-coin-signals.  While the other guy has 10 or 15 wheaties, a few silvers, and ... yes ... no V-nickels.   Ok, you tell me :  Who got the most oldies ?  See ?


So the objective will need to be stated ahead of time. 





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Also :  Greg is one of two dealers in CA who thinks they can tell aluminum apart from gold .  With certain machines.  Not sure if he's now including the TDI in this claim.   But if you challenge them to "show this ability" in actual field tests, you will hear the sound of crickets.  


Here's the trick of the mind they are falling for :  If you wave a few gold rings, and a few tabs and foil wads, in front of a detector in an air test, THEN YES:  Each one will give a "different sound".   So at first blush, it might *seem* that a person can tell "aluminum apart from gold".  Right ?   But no :  What this fails to realize is that SO TOO does every gold ring sound different from each other.   And SO TOO does every random aluminum blob or tab-type sound different from each other.   Any attempt to alert them to this mind trick falls on deaf ears.  So you have the poor buyers, who have seen this air-test-parlor trick. Who are convinced that if they "ascend to this master sage level", that they can somehow tell aluminum apart from gold.


Mind you, no one's asking to leave "all the gold behind" and dig "only gold".  Heck, most of us would be happy if the odds were 50 to 1, or 100 to 1, etc....   So when you try to pin these guys down on what the ratios would be (assuming their claims are true ) in junky urban parks, you begin to realize that this nothing more than random eventual odds.  Or simple ring-enhancement programs of sorts.  

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Tom_in_Ca any further discussion with you I will yield to Steve H. comment below:

On 4/14/2021 at 2:15 PM, Steve Herschbach said:

I've used PI detectors to pull coins out of parks your VLF is not going to hit. That's not the same thing as telling people to buy a PI for park detecting. If the circumstance warranted, I would pull out a PI to hunt a park. But wisely, using smarts. Most commentary about all this stuff seems to assume people that have no clue as to strategy and tactics, and using the right tool for the job. I know my tools, I know what they can do, and I will use any of them in any situation I can imagine where it might offer me an advantage. I will use Equinox Beach Mode to hunt nuggets in a desert, and know of a case where that would be beneficial. I do not make rules for myself like "can't use PI in park".

Please read and reread as needed.

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There is no doubt that a PI will get coins that a VLF is "not going to hit on".   That does not need to be "read and re-read"  It is undisputed.  The question is :  Can that ability be parlayed into junky park turf hunting ?  Or is "The devil in the details" ?


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5 minutes ago, Tom_in_CA said:

There is no doubt that a PI will get coins that a VLF is "not going to hit on".   That does not need to be "read and re-read"  It is undisputed.  The question is :  Can that ability be parlayed into junky park turf hunting ?  Or is "The devil in the details" ?


No offense Tom, but the GB posted this so he could get advice from PI guys for a certain situational hunt. You hijacked this thread so you could push your views on how PI guys are incorrect about this or that. Who cares! Start your own post on it. You come across as pushy when you don't win the argument. I'm surprised Steve let this off topic go so long.

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