Jump to content

Recommended Posts

  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.

  • Like 1
Link to post
Share on other sites

  • Replies 51
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

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

Posted Images

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:

TDI.PNG.1a2489a6ff6d6143dcd36dbd937ae5e6.PNG

  • Like 1
Link to post
Share on other sites
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.

Link to post
Share on other sites
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.

  • Like 3
Link to post
Share on other sites

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.   👍

  • Thanks 1
Link to post
Share on other sites
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. 

 

 

 

 

Link to post
Share on other sites

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.  

Link to post
Share on other sites

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.

Link to post
Share on other sites

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" ?

 

Link to post
Share on other sites
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.

  • Like 2
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Similar Content

    • By RickUK
      Would like some help please on a specific coil for my TDI Pro,i have the option of buying this brand new Coiltek 6'' Mono coil which was of course specifically designed for the GPX range of detector,the GPX Mono coils do work very well on my TDI Pro as i own and use most of them on the TDI.
      Has anyone specifically used this small 6'' Mono coil i am looking at using it most of the time because i am using smaller coils more and more due to the problems that i am hving with a broken wrist that i had from a bike accident decades ago,does anyone have any thoughts on this combination please.
    • By Steve Herschbach
      My first comment regarding discrimination with a ground balancing PI like the TDI and others is that people may be expecting things of the TDI it cannot deliver, and may be better off with a good discriminating VLF detector. If your priority is discrimination, no PI will discriminate like a VLF.
      There are two ways to tune the TDI. The first and preferred option is to tune the detector for the best depth. On low mineral beaches ground balance "off" usually give the best performance and you generally have to dig all targets. The sensitivity control and pulse delay are set to the desired level of quiet operation. You have to adjust those settings for your conditions. Forcing it by using settings other people use is fruitless. Salt conditions do vary as does mineralization and electrical interference, and the machines themselves vary by a small amount.
      I notice many people think lower settings will cause lost depth and therefore insist on higher settings, and then complain the machine is unstable. It simply is what it is. Adjust the machine for the conditions. If it does not perform to your satisfaction, use a different detector. You can't make a detector do what it does not want to do.
      As ground mineralization increases on some beaches, there is a point where using the ground balance “on” gives you more depth. Only with experiments can a person determine which setting gives more depth on your beach - ground balance “on” or ground balance “off”.

      If you use the ground balance, it BY ACCIDENT creates two audio classes of targets, those above the ground balance setting and those below the ground balance setting. These give either a low tone or a high tone. The resulting two classes of targets have only a little to do with what they are made of, but are based instead on the rate at which eddy currents decay in the target after the transmit pulse shuts off. Size has as much to do with the audio results as composition, just like on a VLF. The pulse delay sets the minimum level for this eddy current cut off or rejection. See Understanding the PI Metal Detector by Reg Sniff.
      With ground balance “on” you would normally, just like with ground balance “off”, adjust the sensitivity and pulse delay for whatever level produces quiet operation. I usually just put the coil underwater and pump it in the water, and first try lower sensitivity. If that does not remove noise I raise the pulse delay a little and try again. In general I am trying to keep the pulse delay as low as possible and sensitivity as high as possible. Eventually through trial and error I find a combination of sensitivity and pulse delay that eliminates audio results when pumping the coil in saltwater.
      The ground balance setting is determined by whatever setting gives no audio results when moving the coil up and down over the beach or the bottom when underwater. If basalt cobbles are present they may also need to be included in the ground balance tuning procedure. In extreme cases you may have to lower the sensitivity and pulse delay even more to get a proper quiet ground balance.
      Again, once you have tuned everything for best performance, you will have a pulse delay setting and ground balance setting that ACCIDENTALLY creates two classes of targets. The only way to see the result is to test various targets. In the U.S. our coins are much more conductive than many European coins and retain eddy currents better, and therefore generally give a low tone while most jewelry will give a high tone. Large ferrous will give a low tone and small ferrous a high tone. Very large rings may give a low tone as will most silver rings. In Europe and other places the tones may vary from what we see with U.S. coins.
      After experimenting to find out what items give what tones, you have a simple decision. You can dig one tone only, or you can dig the other tone only, or you can dig all targets. The results will be what you have determined by your experiments and if digging only one tone or the other loses items you do not want to lose then you must dig all items. If that is not acceptable, your should be using a VLF detector instead.
      Now, if you are willing to give up some depth, you can try to purposefully misadjust the ground balance control to move the tone division point. Doing so may switch some items from one tone to the other for a better result as regards discrimination. This however puts the detector out of proper ground balance. In mild ground you can do this easily but in highly mineralized ground the machine will now signal when moved over the beach or the bottom or past hot rocks. The depth is lost as you compensate for this by again reducing the sensitivity or increasing the pulse delay. Again it all is a matter of experimentation. If a desired item that is giving a "wrong" tone can be made to give the opposite tone by misadjusting the ground balance you may benefit from this in milder ground. It may be that the lost depth or audio side effects from being out of ground balance are not be worth it. You have to decide.
      To sum up, VLF detectors offer the best discrimination but may not get enough depth on mineralized beaches. A PI detector can get more depth, but any discrimination is an accidental byproduct of the ground balance system employed and will not separate targets like a VLF. In general you dig everything with a PI but in some cases you can derive benefits by digging some tones and not others, but you will without a doubt miss some class of good targets by doing this. That is just the way it is.
      The first ground balancing PI (GBPI) I used for beach detecting was the Garrett Infinium. Next was the TDI and then Garrett ATX. All three have similar tone results, but the TDI has the additional benefit of allowing you to manually set the tone break point via the ground balance setting. I have also used similar tonal separation using Minelab GBPI detectors. I go into more in-depth detail on another post referencing the new Fisher Impulse AQ where I reference all my notes on all these detectors so I am going to link there for further study. The Impulse is basically a refined version of what the TDI is doing, with the ground balance control used first and foremost as a discrimination control, and as with the TDI there will be performance trades depending on the settings employed. Understanding one will help you understand the other.
      This is a very complex subject for those wanting a simple VLF type discrimination system in a PI detector. They are however two different things, and you have to read and think quite a bit about how a PI detector actually works to get your head around all this. Or at a minimum do lots of experimenting and learn by observation. I have tried my best to explain things, but there is no magic tuning or answers I can provide that will make these machines do what people seem to want them to do - act like a VLF. They are not. If they do not discriminate the way you want I have no settings that will make it happen other than what I have tried to explain already. This is kind of a summary and along with all the other posts is really about all I can offer or have to say on the subject. I hope it helps! 
      Fisher Impulse AQ Discrimination Explanation
      Where Will The Holes Be In The Fisher Impulse System
      White's TDI SL Owners Manual
      White's TDI Beachhunter Owners Manual
      White's TDI Pro Owners Guide
      Steve's White's TDI Review
    • By Againstmywill
      This is a rare day for me...3 silver dimes (first time ever)! I went back out for another hour at sunset to see what else could be found in the area I found the Barber this morning. I would never have guessed it would be another Barber day, and the first year of issue at that! The settings stayed the same, and the tones were about the same. I have gone over this area in the past, but when it gets hot and humid in FL, digging a dime isn't worth the effort sometimes. Well, I won't be passing up jumpy dime signals in that area again! It has been very dry here, so I will be hitting this patch of grass again when it rains and lowering the recovery speed. Also, I dug a coin(?) that is 3.1 grams(penny), and it looks to be squashed. However, the thickness is very consistent, unlike a train running over the coin. From one angle, it appears to say 1877 or 1827. Anyone have an idea?
       Equinox 800, 15", Park 1, 7 recovery, 22 sensitivity















    • By Dancer
      Running the Biggin today, reached down for some feint dimes and one nice 9" coin spill.     Real nice coil, cleaning up what was left.
      That spill had 5 nickels 2 dimes and a quarter all stacked.   Numbers were all over the place. But in disc mode easily made out the chimes with the nickel bongs.   Doesn't always turn out that way. High, low or deep, the Biggin was snagging them today.  The spill coins are near the tip of the shovel.

×
×
  • Create New...