On Discrimination

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 6:13 AM

Discrimination. Here the Tarsacci has a most interesting approach. With a strong bad soil capability and the ability to operate in pretty heavy junk comes a sort of PI hybrid feel with better target ID. So far the Tarsacci ID capability seems solid, and it deals with iron very well for something that pulls such small targets. One can argue about ranges maybe, but for an urban gold hunter the range a person would care about is pretty well defined and every good signal in that range is going to get dug. Or is it?

It is pretty uncommon to be able to pull fairly small gold yet ignore much foil without apparent consequence. And look how bad the iron can be and still hear only faint whispers of falsing. And with a little ear training, even more common junk may be passed by with a fair degree of confidence that nothing good is being left behind. Really, what more can be done?

Well, there is always discrimination. The one thing that is not quite so well defined. A person really could special focus hunt all sorts of things while quieting down the competition with a little notch. Of course every self respecting hunter would like to dig it all, but that is just not realistic some places. So, discrimination. Really, it needs to be set somewhere, but where and why for? How do you use it for how you hunt? I put it on +29 or 30, because it sounds best there to my ear and helps prevent iron wrap around. A common recommendation is -30.

How exactly the discrimination works on the Tarsacci is a little fuzzy to me, and worth understanding better. It is what is left to tackle the almost unbelievable amount of junk that sounds like gold. Some places will remain all but unhuntable of course, but Tarsacci opens things up a bit to my mind. Your thoughts would be most appreciated. 

 

Diggin Dude

Dig we must !
New York

Joined Aug 28 2020

Posted on October 7, 2020 @ 9:42 AM

I can't wait to see the replies. You pointed out something I didn't realize regarding the Disc. You mentioned you run it at +30 and hear targets. I automatically assumed that a disc number that high would disc out good targets like other detectors, boy was I wrong. Time for me to start experimenting. I did an air test on different targets last night with disc on +30, everything reported !      Grabbing my popcorn and waiting for Keith, Aaron, and Dave to reply. 😊

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 1:13 PM

Diggin,

That is how the disc behaves below zero. Above zero it  notches the number you choose along with 2 above and 2 below it. Functionally, setting it at +30 would then disc 28, 29, and 30. Any disc setting above zero also takes out everything below zero in the iron range with it. The reason I chose that number was to minimize iron wrap without losing much in high silver. Others choose to use -30 to hold down iron wrap because they want to hear the iron.

It is a personal choice what you want to listen to from the ground. I prefer to exclude all iron sound because the places I hunt are so full of aluminum trash that adding iron to them make a constant barrage I just do not want to hear.

Today I did an experiment where I notched at 16 to exclude zinc pennies and some older crown caps. To get better old crown cap control required going to 15 which worked well. This does nothing at all to help with pulltabs, but it does eliminate two very common targets here that are real time wasters for what you get, without taking much good with it. There is still lots of trash to dig, but it does help some. Setting the sensitivity at 2-3 does weaken trash before it weakens good targets and helps with falsing, but can only be recommended when a person is hunting shallow. If a person really wanted to eliminate pulltabs from there just stop digging 6,7, and 8 and it will get most of them, but some nice rings sit in that neck of the woods and I find it hard to walk by signals that sound that good. A person could just dig high tones and get quarters and dimes and copper pennies, maybe an odd silver piece, and it is easy to do when a person gets tired.

For what it is worth.

Dewcon4414

Florida

Joined May 27 2020

Posted on October 7, 2020 @ 1:47 PM

Well I’m not a dirt hunter anymore.  Strictly beach now, but used to be.  I can tell you what I’ve found on the beach/in salt water.  I found +28 to be my magic number to notch out wrap around iron.  But it didn’t put that iron tone where I wanted it.  Especially when I couldn’t see the screen.  Then there is that distorted sound that ya just can’t break up on big iron.  So -30 seems to do well.  This machine does exceptionally well IDing even deep iron.... so when I flip to disc out of AM I’ve got a good indicator with a low low tone.   In or around salt water ... trash targets bounce to the mid 20s.... like aluminum.  Bad for you good for me.    When gold hunting I can take a day and just dig the two middle tones... from one to 13.  13... a number I wished was in the high tone since it’s often a penny.  Most gold falls below that digit... just like other water machines.  You may catch that rare huge gold ring at 13. I had a guy run his very very large 22k a crossed it and it hit 12.  Foil.... Aaron showed how he can disc out even smaller foil using the salt balance.  But it seems density of the foil comes into play with this machine.  I’m not digging a lot of tiny foil... but I’ve done as well as the Nox on chains.  In fact only 2 gold targets I’ve ever found the Nox hits on the MDT dont... tiny tiny cross and hollow earring.   Also on a lot of machine gold turns to iron at a certain depth.  Thus far I’ve found gold doesn’t upscale to the high digits like aluminum.  I’ve dug a lot of iron at depths and have yet to find a gold ring with this machine.... so the iron ID works well ... take a scoop often proves it.   GL and enjoy the machine.  

Diggin Dude

Dig we must !
New York

Joined Aug 28 2020

In reply to by SLGuin
Posted on October 7, 2020 @ 1:56 PM

Thanks SL,     After I replied I checked the manual and there was the explanation.  I will try +30 though to help eliminate iron wrap and experiment in NYC park hunting conditions. Lots of aluminum trash.        I hunt spots in a river near me that had foundries in 19th century so shore line ground/sand has lots of tiny iron bits and mineralization.

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 2:36 PM

Diggin,

That has got to be some tough ground. If anything can handle it, Tarsacci will. So many parameters to control and all in view all the time. Best thing for bad ground that still gives reliable target ID to my mind. Going over ground like that could offer you a view of that tough ground no one has had before. 

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 3:11 PM

Dewcon, 

Thanks for this very informative reply. It is very interesting how the salt environment changes where the targets land. It sort of makes a person wonder if there might be a way to get the machine to do that on it's own without saltwater. Sure is a nice feature in an environment where most detectors struggle.

13 and 14 are almost always zinc penny here. They give a nice clean hit if they are not corroded yet which is why a swing at discing them out seemed worth a try. There is no doubt at least some price to pay for using the notch that aggressively, but some days pennies and crown caps get really old. 

You are absolutely right about density playing a role. Thank goodness for small favors. Getting that small foil out of the picture really lets a person concentrate on his pull tabs. Surely density of target matters for all of the targets, it shows best in foil for sure though. The cool thing is how it matters more in foil than gold rings. One ring the other day was so small and so fine it could hide in plain sight if the sun did not catch it. With a Gold Racer, that ring and a small piece of foil would sound the same. A person can cover a lot more ground when not digging foil. Can slaw is another matter, but that has a rough edge and rings higher. 

There have been several reports of really big and heavy gold rings coming in above zinc penny. Some to clad dime range. That really makes a person consider discrimination choices carefully. Here it comes down to just how sick of digging a person might be. Those new zinc pennies sound good enough to be big gold, and maybe they are.

It would make sense that chains would be tough to get in a salt environment. Here in milder ground they come through fine. None without clasp have shown up, so that might be a thing, but enough are coming to inspire at least some confidence in Tarsacci's ability to get them.

Dewcon4414

Florida

Joined May 27 2020

Posted on October 7, 2020 @ 3:44 PM

This machine really can break up the iron on bottle caps.   Like 3 different targets.  Corona with copper in them are like silver, then some are just plain iron.... and yet another hits in that 15 target range close to a dime but jumps.  You have to choose your settings and disc based on targets sometimes... with that understanding it’s a trade off.  Some days I’m just concerned about missing coins and silver.

Aaron

TOP MOD
Michigan

Joined May 20 2020

Posted on October 7, 2020 @ 3:50 PM

One of the ways to bust up suspected crown caps is switching to 6khz, that usually reveals them. Here’s a couple videos regarding that....

https://youtu.be/45WDnC1qmH8

https://youtu.be/paBWSSxf_Lo

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 3:55 PM

You are sure right about the crown caps. Disc at 15 gets the worst of them here, but those that ring hard and high are just too good to resist. Today, setting that notch was just barely enough, and did not exclude the clad dimes, but there is not a lot of wiggle room when your notch is fixed at 5 numbers. It was fun doing it as an experiment, but it does not sound quite the same with that notch out.

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 4:05 PM

Aaron,

Your videos are terrific. Have you done any work on the sensitivity to gold in 6 kHz? Most of my work here is for shallow gold and recent drops so 18 kHz is preferred, but if 6 would be better at the thing in general it would sure be worth learning.

Currently, except for experiments, anything not obviously iron with a good signal gets dug. For that, 18 kHz has worked best to my ear. Having gone as low as 9 kHz which I did not care for, it did not occur to me to try 6. That might be a shortsighted mistake on my part.

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 7, 2020 @ 4:11 PM

Thinking on it now, given that Tarsacci is so different compared to normal VLF, it is possible that switching to 6 kHz might take the edge off those pull tabs a bit. It seems possible that it might take the shine off enough at least to make aluminum a little more obvious in comparison. It does not seem likely that even at 6 kHz gold will change much. If it worked it would sure be better than notching them out.

Aaron

TOP MOD
Michigan

Joined May 20 2020

Posted on October 8, 2020 @ 10:29 AM

SLG, 

Im glad someone has finally discovered (and put it in print), what I’ve know since the summer of 2019....the Tarsacci can ignore small foil while still finding small gold! I tried explaining this on the forums and through YouTube and was met w much criticism to say least and once I became a dealer it only got worse. Seems your having a lot of success in the dirt. Please post some pics on the Tarsacci Inland Gold Forum!!!

This has been my best year ever for gold however it was all found in the water. And rarely ever did I ever dig any foil. I’ve gone back to the dirt since the swimming season has ended. No gold yet, however very little foil. I’ve also been doing some testing w the lower kHz settings, to early to talk about though. I do have info to share regarding 18khz on small gold, however I’m out of time and will get back later....

 

SLGuin

US Midwest

Joined Sep 6 2020

In reply to by Aaron
Posted on October 8, 2020 @ 12:57 PM

Aaron,

The difference is striking and not to be missed by anyone who tries the method you describe. Not thick/balled up foil of course, not can slaw, or pull tabs etc, but a lot of small and thin foil just goes away. You can see it laying right on the grass and not hear even a crackle. How anyone would fail to notice that is hard to understand. A lot of digging is avoided, more ground covered, no downside is apparent.

Tried your suggestion on the 6kHz today but still struggling with crown caps. Going to watch videos again and keep trying, but for shallow hunting it is quicker to just pop the thing up with a screwdriver and keep going if there is doubt about it from the screen. 18 kHz is still far better to my ear, but will keep at it.

Aaron

TOP MOD
Michigan

Joined May 20 2020

Posted on October 8, 2020 @ 8:15 PM

Stacy,

I have found though, even the balled up foil has given me a scratchy type of tone, that however was only just below the surface not technically buried. And then I find certain types of foil that can be just a ((little)) bit thicker, the round type that you peel off a sports drink (always read nickel) and on the ends of various containers. Those are going always read good.Then you have pieces of foil that are thicker for whatever reason and they will read as a possible gold target. The point is, your NOT going to be digging every little piece of foil like you would w the Equinox. When I would run my Equinox, every time I'd get a VDI of 1, it was ALWAYS foil. Now if I dug enough of it sure eventually one of the times its going to be gold however how much time do you have to spend on that especially where a lawnmower ran over a big piece of it? I know theres some really sharp jewelry hunters like you that specialize in finding gold in playground, picnic areas, however this isnt for most metal detectorists. The Tarsacci makes this easier, though its still going to take some time and practice. There are a few clues that I have noticed with regards foil range that I will share in a upcoming video soon.

Regarding crown caps....crowns are pretty difficult for almost any machine. Theres a really old park I hunt, its LOADED w crowns. So Im constantly expecting to find them, so Im always double checking w the frequencies, in that area it really helps. However yesterday I was in another old park were there a lot less crown caps, I ended up getting fooled a lot more because I was not expecting them as much, I wasnt double checking. And lets face it, some of them sound REALLY GOOD. So far, as I see it theres no fool proof method of totally eliminating crown caps, and some of them are just plain impossible. However using some of the techniques I've demonstrated can still help.

Diggin Dude

Dig we must !
New York

Joined Aug 28 2020

In reply to by Aaron
Posted on October 8, 2020 @ 9:23 PM

Aaron, your videos and others really help.  I’m looking forward to your video regarding foil range. 

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 8, 2020 @ 10:25 PM

Aaron,

Modern aluminum trash is a problem for jewelry hunters for sure, and every little edge a person can find is a blessing. In some of these places the pull tabs are just too much. If you dig them all, you waste so much time that you do not cover any ground. If you disc them out, you lose prime gold slots. It is always some kind of compromise, and not an easy one always.

A person can learn the sound of some can slaw and foil balls and crown caps, not perfectly of course but some. Pull tabs are a good signal that does not lend itself to that sort of judgement. It is a good solid hit and there are enough shapes and sizes of them to take 5-8 at least on a Tarsacci. 7 is the most common one here, but that is a pretty nice ring slot too. Trying to come up with a decent strategy for the common pull tab is a running battle. It must be confessed that working out strategies for dealing with these things is more than half the fun. 

One thing that does not always get mentioned is competition. Here there is lots of it. The easy places like volleyball courts and sandy beaches and tot lots get hit hard and pickings are slim even though the digging is easy. The places with lots of mid tone junk can drive you nuts but they do not get the same kind of pressure. It would make sense that there is where finds are to be made, mid tone signals are virtually everywhere. You know it is not all pull tabs, but the percentage is pretty low and a person has only so much time and energy for that much digging. There is no perfect solution, not in site selection nor in settings, but I am having a pretty good time working at it with the Tarsacci.

At present, it comes down to what the site gives me. If there are lots of tabs falling at 7, I will avoid that number after a while and dig the other numbers if they sound good. It is remarkably easy to ignore one number with a Tarsacci, because tabs give a good steady hit. Crown caps are a thing worse some places than others, but there tends to be a local type often that you can sort of recognize after a while. If there are few tabs I will dig more of those numbers and less of whatever is the worst trash there. High tone coins are easy and welcome relief sometimes. Because this machine handles the ground so well it gives a person the ability to wade right into some of these places and sort of make educated guesses on what to ignore. Of course you are going to lose some gold that way probably, but you cannot dig it all and cover any ground so compromises need to be made. There is an art to hunting in heavy junk, and you get it all to yourself most days.

 

Dewcon4414

Florida

Joined May 27 2020

Posted on October 9, 2020 @ 7:24 AM

Im going to add this again.   Notice nothing over 13.   Ive done even more gold testing which continues to give the same results.   So .... that pull tap you want to disc out i wouldnt on the beach at least.   Bottle caps...... thats that give that crappy signal..... most are deeper and MOST would sound bad with any machine so you would be digging them.  Basicly you can tell the iron and copper caps just as easily as with other machines.   If you want to disc on a beach i think the chart shows you can.   Also on the beach those tabs and a lot of the can slaw bumps well beyond the 13 digit at depths around 6 to 8".   All this is what makes this a very good beach machine.   That 6.5 khz..... way back when i started hunting many if not most machines used 5 to 7 khz they handled dirt and EMI well.  Im betting the less expensive machines still do.  These machines were never crazy deep but hit well on coins.

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 9, 2020 @ 8:06 AM

Good Morning Dewcon.

Thank you for this reply. You are exactly right. A person would not miss much gold above 13, and some say 1-10 gets most of it. Here, scratchy ratty sounding signals of any number seldom turn out to be worth the effort. For my particular application, we are talking extreme junk where every step or two offers a good sounding signal from a pull tab or other modern aluminum junk. This is not to be confused with regular park hunting or beach hunting at all, it is hunting in a sea of aluminum trash for gold which comes it at the same mid tone slots. To dig every pull tab from a place like this is not practical, that is why some are picked to ignore at some places and not others. When doing a 10' circle around a nice shade tree gives you 20 good sounding targets all falling in at less than 13, some trade off must be made.

There are a few basic things to do with this kind of situation once determined to take it on as opposed to finding easier digs. Choose settings that weaken junk signals if you can, disc out some of it, ignore some of it, and dig enough of it to be reasonably certain you are getting some time back for what you are intentionally choosing to walk past. Unless you dig everything you cannot be 100% certain you are getting it all, so the basic idea is to pick a percentage you can live with in a given site and have enough idea what that is to make it a logical intentional choice.

Having tried all frequencies in this heavy aluminum trash now still makes 18 kHz superior to my ear. The signals just sound better to me, and the numbers seem better or somewhat more stable on shallow targets. I do not have any technical knowledge of why or how this should be so, not for any of it. Just working it out a little at a time and sharing what seems to work. It is still specialty hunting of a sort, for most common sites I would not be this aggressive excluding signals. 

Dewcon, your excellent input really helps. Thanks.

S

 

 

Diggin Dude

Dig we must !
New York

Joined Aug 28 2020

Posted on October 9, 2020 @ 10:03 AM

Aaron, I was watching this video of yours (again)  https://www.youtube.com/watch?v=DI3JWd_sThs      May be a dumb question but would it be safe to say to eliminate small shallow aluminum or gum wrappers with salinity balance at 34 at 12khz before hunting a trashy park?   

Aaron

TOP MOD
Michigan

Joined May 20 2020

In reply to by Dewcon4414
Posted on October 9, 2020 @ 10:18 AM

Dew, Agreed. 

13 on the VDI is going to be a BIG gold ring, 10+ grams, even in the water that’s RARE. My biggest gold this year in the water was 5.5 grams and that was I believe 7 VDI. My average gold is usually only 2-2.5 grams and those average 5 VDI. I attribute this to the TARSACCI’s ability to find small gold in high trash/iron where others avoid.

Dude, I have something coming this evening that may answer your questions....

 

Aaron

Dewcon4414

Florida

Joined May 27 2020

Posted on October 9, 2020 @ 10:20 AM

I’ve got a very good idea of the places you talk about.  I used to hunt the 1800s parks in Indy.   Get close to any picnic table and it was unbearable.  So a pattern search and even reduced sensitivity with a small coil helped.   I’d say you can do the same thing adjusting the GB. Anything that affects the sensitivity affects the FILTERING process.  Which reduces noise .... just like a faster swing reduces smaller or deeper signal.   How much is to much?  

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 9, 2020 @ 12:14 PM

Aaron,

Do you think there is a linear relationship of the ID# and weight? There are reports of super big and heavy rings running right up to dime range. Rings that heavy anywhere are very rare, but there does seem to be something there to do with absolute mass because heavy rings are not really all that much physically larger than small and fine ones, they just have more metal in them. It cannot be size or those foil top things at 2" across would not come in at nickel. Reports of high karat and fine wire gold rings show them coming in quite low sometimes. Of course we know these numbers are not based entirely on conductivity, and it is not completely about size either. Shape surely matters, anything round comes in well no matter what it is made of. Thickness and density clearly matter as evidenced by foil. Interesting.

Dewcon, 

How much is too much indeed. Could you expand a little on using GB for this purpose?


S

Dewcon4414

Florida

Joined May 27 2020

In reply to by SLGuin
Posted on October 11, 2020 @ 7:39 AM

Ive done some raw gold hunting ....to hear targets you set your GB less than the ground which makes it a bit noisy mineral wise but you hear more of the weaker targets.  If you set the GB to high you FILTER those targets out.   I dont know if you have the ML manual for say the Nox....... it shows kind of a wave up and down based on how your set your GB....... if you set it to high it reacts much like Keith/Aaron have shown with the SB.  You start loosing weak signals and because of the filtering your machine begins quieting down.  Its also like setting your threshold....... the higher you have it the more noise you get and weak targets get lost in all that noise.  Thus most set it just so they barely hear it.   The Xcal is a good example if you hunt in disc or PP mode.  In disc you want the threshold just so you can hear it........ but you gain depth on targets in PP by setting a bit louder.  

Ive never found a gold ring higher than a penny.   But ive found class rings and a GMC ring nearly 30 grams in that range.  Id say ... weight, size...... AND K (metal combination) all play a part. 

SLGuin

US Midwest

Joined Sep 6 2020

Posted on October 11, 2020 @ 9:57 AM

Dewcon,

Thanks for this. It really helps to arrive at a rational strategy for a very unique detector.

Diggin Dude

Dig we must !
New York

Joined Aug 28 2020

In reply to by SLGuin
Posted on October 12, 2020 @ 10:16 AM
So I did some experimenting this weekend Using the discrimination subjects covered in this thread. I went to what I consider one of the most trashy parks I could possibly find in my neighborhood. Lots of small foil, canslaw, Crown tops, aluminum tops like Schaeffer and RC “look” caps LOL, tons of pulltabs etc. I just did a salt balance as per Aaron‘s video to remove the small foil and Wala, I was able to remove it. I had a salt balance of 38 which worked best. I was also in the 6 kHz search frequency. Found the discrimination. I first tried Stacey’s method of +30 on the discrimination. Removed iron wrap and I was able to hear everything between zero and I believe 28. Quarters came in anywhere from 21 to 23, dimes and pennies varied between 18-20. It seems the crown caps seem to hit consistently above 22 they were more like 23 to 26 but in other direction would drop with 90° coil sweep change. It actually got to the point where I was calling them out. But I could not really discriminate them out. What I didn’t understand about the discrimination was I decided to discriminate out pulltabs because I was coin searching not looking for gold. So I discriminated up to 16. But still received audio bells tones for lower range like 03-13. Why? I thought they would be discriminated out. Perhaps they were or I am just confused. One thing I will say is this machine punches deep I pulled a wheat penny which had to of been 9 inches amongst the trash I was amazed. Managed to yank one silver Rosie 1959D, three wheat pennies all deep, and lots of change. Pocket knife but lots of aluminum bottle tops which you really can’t get rid of. In the end I think I like the +30 discrimination setting for trashy parks with a higher salt balance. Seems to work well fir my ears listen for the higher pings well coin shooting in mixed mode. The next thing will be going on the sports field. The infield has grown over and is now grass, I’ll be looking for gold rings. I’ll keep you posted and when I could do that.