Can one tell by the Ground Balance number if the mineralization is high or not?

[Kevin B.]

My Xterra 705 Ground balances at around 60. And yet, with the 5x10 DD coil (18.75) it will hit a silver Rosie dime at only 4 inches. It gives iron grunts at silver dimes buried at 5 and 6 inches with occasional chirps. And even on the 4 inch silver dime, the number doesn't lock on and stay but fluctuates from the 20's to the 40's.
I am trying to figure out if I might should have went with a Concentric coil. My soil has always stunted the depth of the vast majority of detectors that I tested in my test garden, calling most items iron. Please bear in mind that I am a total newbie with the Xterra. And I'm relatively a newbie with all detectors since I started detecting a year and 9 moths ago. I am determined to figure some stuff out. But sometimes, I don't even know what questions to ask. Thanks for any and all help.

 

[7centsworth]

The lower the number the higher the minerals. 60s is low minerals. You would have done better with a concentric for sure. When My ground is in the 50s I do really well with a 9 inch coil.

 

[Old Longhair]

It's not quite that simple I'm afraid. It has to do with a number of things, but what's most important to you is how the mineralization where you are responds to different frequencies, and how it combines with target metals. It is important to note that there are two ways to measure mineralization. There are both conductive and magnetic minerals, and levels of each can vary independantly from each other, and will have their effects on how targets are interpreted.

That said, anywhere that minerization is an issue, you're best off with a DD configuration coil regardless of frequency chosen. The concentric coil would likely perform poorer, unless the minerals respond to the lower frequency enough differently. If you want another coil, I'd recommend a DD of a different frequency.

JMHO

I had to come back for this.
First of all, 7centsworth is correct inthat GB numbers of 60 indicate minimal minerals, but.....again there are other things to consider like ground moisture level etc..

And I wanted to ask a few questions like....
What Mode are you in?
Do you have the GB Tracking turned on?
Is GB Beach turned on?
Is Coins + engaged?
How many tones are you using?
Where is your Sensitivity set when the threshold is stable?

 

[GTzer]

Another interesting twist. Sure would like to hear more on the anomolies of mineralization. So far for me-low mineralization (high GB numbers) and moisture provide better depth and TID. Got the Gold version because I assumed that SE Pa was highly mineralized. 18.75khz works great in rocky/gravel areas and at the beach. 10.5" -7.5khz & 3 khz CC work better in most of the soils with GB #'s 25 and above.

Old Longhair- is there any place that I can read more on that-specific- info you provided?

Kevin B- are you in AM or DISC? I had to use the 18.75 for several months until I could afford other coils. I was still picking up clad dimes and other coins 6-7" in soils from GB#'s 17-36. Since I was trying to learn I would check out most targets several different ways and try different options to pinpoint before I would extract. The majority of targets would read on both AM & Disc. + target ID would sometimes lock or stabilize a TID number better. I even would move the sensitivity (again before digging) -the results helped me learn the MD better.
Remember to turn off the GB tracking if you are studying a target. You get a lot of variety in TIDs and the target can get GBed out completely.

 

[Kevin B.]

First, I appreciate all of the replies. Secondly, I must say that I am confused over all of this because I always assumed that since my soil seems to shut down good signals, not only on the Xterra, but all the others as well (accept the Deus, it hits all the targets and most, with a good number).
But first let me answer Old Longhair's questions:
1) What mode: Coin and Relic
2) When testing my test garden, I auto GB (pumping). It auto Ground Balances to 60.
3) I don't know if I have inadvertantly turned Beach on or not. I'll check after re-reading instructions. And then, re-ground balance
4) Coins Plus?? Same as Coin and Relic mode??? Yes
5) Two tones
6) Threshold stable? I just set the Threshold to be barely audible as indicated by instuctions. I assume that it's stable. It IS audible, but barely. I can hear a steady hum while detecting in COINS AND RELIC mode. I have tried the sensitivity from 20 to 30. I spent a couple of hours tweaking at the test garden yesterday.
I found Hardin County Tennessee's soil map and legend last night while resraching soil conditions. Our soil is considerd highly acidic. They didn't show reading for iron, zinc, copper, and other metals. I was hoping that they would. The soil is definitley reddish brown. The moisture is perfect. It is moist enough to make a clod in your hand and it not fall apart unless ya drop it from waste high. It would be too wet to plow right now. I will check and see if I am in beach mode or not.

 

[Old Longhair]

2) When testing my test garden, I auto GB (pumping). It auto Ground Balances to 60.
3) I don't know if I have inadvertantly turned Beach on or not. I'll check after re-reading instructions. And then, re-ground balance
4) Coins Plus?? Same as Coin and Relic mode??? Yes
5) Two tones
6) Threshold stable? I just set the Threshold to be barely audible as indicated by instuctions. I assume that it's stable. It IS audible, but barely. I can hear a steady hum while detecting in COINS AND RELIC mode. I have tried the sensitivity from 20 to 30. I spent a couple of hours tweaking at the test garden yesterday.

OK. First, the XT-705 when properly setup will likely hit on anything that the Deus will, but being a different technology it will just handle it differently.

Next, Auto GB is fine. And fixed GB at the test garden is fine too, but on a hunt somewhere it might not work as well as GB Tracking. It all depends on how much variation there is in mineralization. Where I am, I just about have to run with GB Tracking ON because I can see 20 points difference in GB over 50yds at some sites.

Another thing to read up on (in Randy's book) is the GB Tracking Offset feature. You can use it to alter the GB setting by a few points to essencially "fool" the machine into thinking that the soil is more (or less) mineralized than it is. The result of running a positive offset is that it will often stabilize or solidify a TID. It ONLY works in Tracking Mode.

Beach Mode is easy to inadvertantly turn on. Press and hold the GB button for three seconds to toggle. Just know that GB in Beach is very different than GB in Coin & Relic, so be sure to re-GB whenever you swich modes.

Coins +......my bad. I meant to say ID Stability, which is indicated on the screen by a "+" sign. It too can be useful in hot ground to stabilize TID's on some targets. More info on it can be found on Pg 20 in the owners manual and in Randy's book.

Tones. I never run one or two tones. Three or more is much more useful. Look at the tone break chart on Pg 38 of the owners manual.
Personally, I run with "99" tones (actually only 28 tones). Each target segment gets assigned it's own tone (28 segments=28 tones). This helps identify likely good targets w/o having to rely on the ID screen. Instead of having to depend on my deteriorating hearing to dissearn all tone quality variations with few tones, I can listen for fewer variations in multiple tones to determine the viability of an idicated target.

Stable Threshold is where your Sensitivity is set to keep the "chatter" under intolerable levels (w/o excessive nulling if in DISC mode). I've found that it really needs to be a little higher than "Barely Audible" to be able to hear any variation in the Threshold tone, which can be an indication of a deep target that doesn't give a hard response. I've encountered ground that is hot enough to call for Sensitivity settngs to be as low as 10-12 before, so don't limit yourself too much on how low you have to go to obtain desired results.

Along with all of this, you need to be aware of how the TID's are effected by frequency. For a good explanation and an illustration of this, please check out Pg 82 of Randy's book.

And if you have any other questions, by all means feel free to ask. You have a great machine. When it all clicks in your head and it all comes together, you'll be amazed at what it can do.

 

[Kevin B.]

Oh I am not giving up on it!! And I appreciate the help. I went outside and auto (pumping) ground balanced. Again, at 60. I read up on, and utilized the offset in Tracking mode yesterday, hoping that would help me to pick up the 5 and 6 inch dime. The ground is wet this morning but I have it mowed real low on my test garden. So I headed over there and re-ground balanced (60 again). Tracking is OFF. No umbrella icon, so no BEACH. Sens at 30. Threshold a bit higher than barely audible. Still in two tones. Volumn at 30. I started on my bullets buried at 7,8, and 9 inches. It did better on the 7 and 8 inch bullets. When I first sweep over them they sound of iron but I would get a one way hi tone from every direction. I would dig that. And as I circled the targets, especially the 7 and 8 inch, I would occasionally get a two way hi tone. It did better on the bullets this morning. I headed up to the dimes. 4,5, and 6 inch. freshly buried. Re ground balanced. 60 again. It would hit the 4 inch silver dime with two tone response. The 5 and 6 inch, iron grunts. I will try different tones.
I also did an air test this morning. I tested until I heard a two way chirp:
1973 copper penney: 9.5 inches
1971 clad dime: 9 inches
1986 clad nickel 11.5 inches
2000 Quarter 10.5 inches
1934 Mercury dime: 8.5 inches
1948 Washington silver quarter: 10.5 inches
1865 2 Cent Shield coin: 11 inches
This is on par with what I have been seeing on Youtube for the 705. I noticed in the sticky at the top of the page that two of the CoilTek 15 inch DD( 7.5 khz and 18.75 khz) air tested a dime at only 10.5 inches. This test was performed by Digger. And considering that my coil is 10 inches long, I think that my air test indicate that the coil is okay. (You know the first thing that one wonders is: did I get a bad coil or a bad unit?) But I think that my unit is working fine. But that is speculation because I really don't have much but a handful of youtube videos to go by. And one of those is using a Concentric coil. But the DD coils ALWAYS worked better in my ground for some reason. Anyway, thanks for the help.

 

[DirtAngler]

Hopefully not to confuse you, but go into the FAQFAQ section and find the article BarnacleBill wrote about determing ground mineralization. The GB number you get is a little different, Digger refers to it as a ground phase number, kinda works on the same principle but a little different. Anyway, I think I'm correct on that, correct me if I'm wrong Randy.

 

[ramairnut]

I read that you are running the sensitivity at 30.This statement is straight from Digger's book on sensitivity:

However, do not be misled into thinking that a higher Sensitivity always
results in more depth. In areas congested with adjacent targets, or areas
with high levels of mineralization, running a high Sensitivity can have an
adverse effect on the depth of detection.

 

[Kevin B.]

I read that. But according to the E Book, and my Ground phase being at 60, then my soil is NOT mineralized. But I spent much time out there tweaking each setting. ALWAYS IN ALL MEAT!!! Discrimination patterns made the few good signals choppy. My dirt is NOT sympatheitic to VLF's. I have had this problem even with F75SE's. Most units call those buried bullets iron.
But in other news: The Prospecting mode of this unit picks up all the targets with a change in Threshold (the pitch goes higher). I mean, it slams on all those dimes, they are not even a problem. I even have a bullet buried at 12 inches that the prospecting mode will hit. I already have a great unit for trashy old homesites and square nail cluttered areas that has proved itself time and again. But NOW I have a perfect woods, field, battlefield, detecor when I hunt a site where I dig all sounds 'cause they could be something good. And this unit will actually reach down DEEP!!!!! in prospecting mode. And sensitivity can be at 22 or 23 and it STILL slams on every buried target, even the 12 inch Minie Ball bullet. And I have several places that call for that kind of depth and ability. And I've not even tried Iron Mask in that mode yet. In fact, there is SO MUCH that I haven't tried, I shouldn't have let myself detour of the original question about my soil. More to come. I have high hopes. But it's USER stuff I'm working through. The detctor works just fine. I just no longer buy into this: "OH,THEY SENT ME A DUD!" any longer. The DUD is the man typing this out. If we can get him(me) straightened out. everything will get sorted. I got some studying to do.

 

[7centsworth]

You may want to check your test garden for any trash that may be in the dirt with the bullets

 

[Old Longhair]

Another thing that you might want to read in the e-book near the end, is Randy's theory on circular discrimination. It applies to how the machine can see a target near the top or bottom of the discrimination scale and put it at the wrong end. Some call it a wrap-around effect, but Randy's explanation makes it easier to visualize in your mind what can be happening. And it's a phenomenon that is also effected by frequency choice, as well as how soil conditions combine with various target metals.

If your interest is in open field hunting for things as large as minnie's, and if the area is free enough of trash to run in prospector mode, then if I were you I'd be saving my shekels for one of the Coiltek 15" All-Terrain loops.....and a good shovel.....'cause you're gonna go deeeep!

 

[Kevin B.]

Thanks for the replies gentleman. I am so grateful that you took the time to answer my questions.