Max Depth and Sensitivity - Some Findings

[earthmansurfer]

Preliminary Note - I understand if you have bad ground mineralization levels you can't do what I am about to say (fog in headlights analogy), but just take this into account as I have played with a few deeper targets and the results are clear. My ground is somewhat iron mineralized. I can run it hot but it does false alot - BUT the falses are easy to distinguish.

I got back to my old 500 year old castle spot, which has mostly stopped producing. The CTX has pulled a few deeper coins from it lately. In two hunts I got 4 coins in 3 hours or so. I had hit this spot with the E-Trac (stock and 13" Detech) and got 2 coins in over 10 hours - both low conductors). So, knowing that it's mostly cleaned out I decided to run in manual 30 and deal with the falsing. The machine recommended 15 - 18 to give you an idea.

Settings:
50 Conductive
Minimal Disc (mostly bottom right corner)
fast off, deep off, ferrous coin

Case 1 - My first keeper target was a zinc Nazi coin at 6". It hit ok on manual 30. I tried it on auto +3, which amounted to 20, and it just thunked. Nothing I would have dug.

Case 2 - I was in the middle of my most productive spot. Lots of iron there. I got a faint inconsistent hit at 8", but a 4 way - no way could I detect this coin any deeper. I have to stress this was what most would call a bad hit but you could tell something was there, was not a false. Interestingly, in ferrous coin the crosshairs was showing the target consistently at 12 33 or so (correct ID). I was able to pinpoint it and it pinpointed small. At exactly 8" I recovered a silver 1824 King Max Josef Silver coin - I was shocked (yes, again!). It wasn't quite flat and so was actually in the side of the hole (and I scraped it retrieving it, though I was careful. Pretty worn as you can see so no biggy.) This coin weighs 2.3 grams, just like a clad dime but it's thinner and maybe 20% wider. I tried the detector in auto, it settled on 25 and nulled on the target. Now, that was interesting. At fringe depths running sensitivity at absolute max does help, even with sensitivity relatively high in auto.

Just for comparisons sake, I got tired quicker from running combine and hearing iron than from running 50 CO and hearing the false or two every swing (they are easy to hear and not that hard). I'm not knocking combine - Actually I'm wondering if Combine hits deeper targets a bit more solid as there is no warble in it and since that upper bin can be set quite high in tone, I've noticed targets stand out a lot. But I didn't check this target in combine.

It appears at near max depths for your soil that that extra little bit of sensitivity really does the trick. Perhaps I could have hit that coin in manual 25 or so, didn't try as time was winding down, but I will in the future.

I'm curious if anyone else has experienced this. I'm not saying to do this all the time, but if you have a hunted out spot, running the machine as hot as you can handle it does produce. Had I not done it, I wouldn't have found two coins in one hour at this small subsection of my hunting area.

I noticed the same above behavior on the E-Trac regarding depth and sensitivity.

Albert

 

[etracjoe]

Very interesting testing. And a superb save from a hunted out spot. I was with a friend today that has an Etrac and he was running in auto plus 3 and I too with the CTX were running in auto plus 3. His sensitivity was at 19 where mine was at 28 I was also able to dig a faint indian that he could not really hear. We were in the woods at an old church site and I had a few conductors that I missed with my Etrac when I had it but they sure popped today with the CTX!! I dug 2 flat buttons and an indian. He dug a brass whatsit. I hammered this spot with the big E. I had more good conductive hits today but after digging the hole I lost them with the dang garrett pinpointer I really miss my x1. Thinking of getting the pistol probe. Or maybe Minelabs new probe?? Well anyway back to sensitivity. I really need to start giving manual a go. Jimzilla uses manual and does not have much trouble deciphering what the CTX is saying but I need a little more "ear practice" I definately believe there can be an advantage for what targets he found that were semi deep hit more solid then me running in plus 3 auto. But nothing so far has been out of my range running in plus 3........or so that I know of!! Only time will tell but so far in these 250 year old woods auto plus 3 does the trick.......on the other side of the pond.......thats a different story.

 

[swingman]

Nice - love that old silver!
With my older Sovereign and Explorer SE, I've always been a believer in pushing the Sens. near or at maximum (never quite bought into that fog/headlights analogy, especially for higher-end Minelab machines). I've always relied on 'hearing' first, and I was able to get beyond the 'craziness' of my first Minelab experience (the 'calliope' of full-range sounds) with the encouragement to stick with it, from the forums. Now can ignore the falsing, pretty much. I know what you mean by a signal that was somehow different than falsing.
So far I'm running the CTX at 30 Sens. (with the suggested level between 13 and 18 ) - the manual ground balancing and the (God bless) noise cancelling make it quieter than my SE at max.
AND - I've never trusted the auto-sensitivity on my other machines, and probably never will. The opinions in Sabisch's book I agree with...the 'auto' feature tends to underestimate the sensitivity that can be used, at most sites. The 'quietness' is nice, but I don't want to miss anything and will deal with the falsing.

 

[pspr]

Thanks again Albert and others for your insights. They are truely helpful.

 

[Ron (CA)]

I have compared SENS on may deep targets here in N CA where we tend be be bit mineralized.

On a deep signal the other day: I originally heard it at MAX (30) and then a buddy and I checked a bunch of setting but as far as SENS goes, the best tone was actually at 28 and it dropped off around 25. AUTO +3 = Nothing

Now if you simply want raw depth then I agree that 28-30 may be the way to hunt and just deal with-the falsing.

I think the AUTO function shines brightest if you are picking through the trash and not necessarily trolling for the deep targets. The nice thing about the CTX is you have all the versatility you need for any type of hunting.

Oh yeah-- the target was a 8 inch wheat penny. Not a glorious find but that is about as deep as I was digging with the Explorers in our ground so I am convinced that I am not sacrificing any depth with the CTX.

In 50 CO, Fast on, All the ground settings heard the 8" wheat but High Trash seemed to sound the best. I mainly hunt tones so did not pay much attention to the VDI jumpiness but they all were jumping 36-40 so I had a good idea it was a wheat penny.

Just my two cents for our type of soil.

Ron

 

[Big Boys Hobbies]

Good post! Worth looking into!

 

[jimpugh]

n/t

 

[Digger]

Congrats on the excellent recovery. That silver 1824 King Max Josef is beautiful. I won't recommend you try this.......... but just in case you're curious.......here is something I did a few years ago, using an 1877Seated US dime. I call it my D-cell electrolysis.

Here is a pic of the silver dime after it was rinsed in fresh water.

[attachment 237881 1877dimebefore.jpg]



I took a glass coffee cup and filled it halfway with warm water. I poured in 2 tablespoons of salt and stirred it until it desolved. I layed the dime in the bottom of the cup and stood a D-cell battery on top of the coin, with the positive terminal pointing up. Then I filled the cup with just enough warm water to cover the positive terminal. Almost instantly, I could see "debris" flowing from the dime (negative terminal) toward the positive terminal of the battery. I waited a couple minutes, removed the battery from the electrolite solution, rinsed off the dime and here was the result.....

[attachment 237882 1877dimeafter.jpg]



Again, I do not recommend anyone clean their coins. Especially if they are extraordinarily valuable. However, if you are considering cleaning your silver coins, you might want to try this inexpensive process. I will warn you to take it slow, and exercise caution handling the battery in water. When I was cleaning a few other silver coins, the first D cell had an apparent leak in the seam, causing the case to become real hot after about two baths.

JMHO HH Randy

 

[Schultzie]

Nice tip, thanks Digger!

 

[earthmansurfer]

Thanks for all the nice comments guys.

Ron - Great post and point taken. You discovered something important for your soil. If you soil is consistently at the same mineralization level then it sounds like 29 starts to get you "brights in the fog" but 28 is your optimal setting.
I can run 30 pretty good as you can see, but I need to check on my fringe depth targets in my soil to really know, so thanks for the reminder.
And yes, if you are in trashier ground then auto might be better. If the targets are deep then I can still deal with falsing though. The spot I am hunting has a fair amount of clad in it and I don't dig anything less than 6" unless it just sounds deep from my gain at 23. I don't have small bits of aluminum though, so I can pretty much blast the ground. That said, when I first go through a site I will just use auto as it is plain easier on me.

Interesting that in your ground high trash sounded better on a penny than 50 CO. I notice the exact opposite (at least as far as the cross-hairs go - they are super bouncy quite often in high trash, but not on non-zincs that I can see). I can rule out high trash in my ground as ferrous coin is best with ground coin a close second. All of this checked on fringe depth targets in my ground, which is only 9".

Digger - Wow, what a cheap solution for electrolysis. LOL. I made one once before using charger - it lasted 3 hours before burning out and it did clean well. Also, they are like magicians if you leave your coins in too long.

I won't post the face of the coin as I got it good :-(

Albert

 

[jimpugh]

n/t