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Garrett at pro ground balance

brandon2014

Junior Member
Joined
Apr 9, 2014
Messages
55
I have a Garrett at pro and my ground balance comes in at 88-90. Does this mean my soil is highly mineralization. And how will this affect my depth.
 
It does mean highly mineralized. Mine typically reads 77-80 something here in Va. And have even had it reach 90.

I will usually auto GB it then back it down manually a notch or two.

Also various things like if it has rained seems to make a difference as well as making sure you ground balance in a spot without metallic objects present.

I still get very good depth however.
 
It does mean highly mineralized. Mine typically reads 77-80 something here in Va. And have even had it reach 90.

I will usually auto GB it then back it down manually a notch or two.

Also various things like if it has rained seems to make a difference as well as making sure you ground balance in a spot without metallic objects present.

I still get very good depth however.

So because my ground balance is sometimes 92-93 does that mean my ground is highly mineralized? What about salt water @ 10? Is salt water highly mineralized? Is the middle numbers the most neutral soil? Does it have to do with how acidic/basic the soil is?
 
Heavily mineralized soil will tend to reduce the penetration power of your detector ground balancing is required to help reduce the effect.

Isaac , Yes..you must be in Va. :D

I have not beach hunted with it but generally speaking the numbers are lower in sand from my understanding unless it's black sand...

I would assume in neutral soil your AGB would set to zero ...which will never happen.

Presence of minerals...not sure about acidic effects and etc.
 
It is my understanding that a high GB number (90's) indicates high iron content and a low number (30's) indicates high salt content. So I also guessing somewhere around 60 would be about neutral soil.
 
I have a Garrett at pro and my ground balance comes in at 88-90. Does this mean my soil is highly mineralization. And how will this affect my depth.

How are you determining you are ground balancing in an free of metal targets?
Attempting to ground balance over metal targets is not a good practice.

The AT Pro owners manual, page 32 reads,
"Typical Ground Balance Ranges: 80–99: Highly ferrous (magnetite, ferrous oxide minerals, black sands, hot rocks, terra cotta)"

The owners manual, page 31 reads, "Detector performance can be negatively affected by ground mineralization. The AT Pro can be ground balanced either automatically or manually to cancel unwanted ground signals and obtain maximum stability and target detection."

Ground minerals may be a combination of magnetic minerals (high VDI) and conductive minerals (low VDI). Your ground balance number may be a factor in determining dominant mineral CONTENT, but not the QUANTITY of minerals. DD coils help as they analyze less ground per sweep than the concentric coil. Signal strength is lost due to high quantity of mineralization. The AT Pro does not have the ability to determine signal loss. Manually adjusting ground balance on the negative side (under-tune/negative bias) can help sensitize the machine to higher conductive metals under certain conditions, but makes the machine less sensitive to lower conductive metals. Manually adding to ground balance numbers (over-tune/positive bias) will help sensitize machine to lower conductive metals and less sensitive to high conductive metals in certain conditions. Hot rocks, cold rocks, charcoal turned into coke from old buried fire pits along with iron are potential issues for any detectorist. Ground conditions are the determining factor at the area of the site you hunt along with the metal you are seeking.
This would be an important concern for relic hunters and deep silver hunters, not a concern for general park, school or fresh water hunting.
 
How are you determining you are ground balancing in an free of metal targets?
Attempting to ground balance over metal targets is not a good practice.

The AT Pro owners manual, page 32 reads,
"Typical Ground Balance Ranges: 80–99: Highly ferrous (magnetite, ferrous oxide minerals, black sands, hot rocks, terra cotta)"

The owners manual, page 31 reads, "Detector performance can be negatively affected by ground mineralization. The AT Pro can be ground balanced either automatically or manually to cancel unwanted ground signals and obtain maximum stability and target detection."

Ground minerals may be a combination of magnetic minerals (high VDI) and conductive minerals (low VDI). Your ground balance number may be a factor in determining dominant mineral CONTENT, but not the QUANTITY of minerals. DD coils help as they analyze less ground per sweep than the concentric coil. Signal strength is lost due to high quantity of mineralization. The AT Pro does not have the ability to determine signal loss. Manually adjusting ground balance on the negative side (under-tune/negative bias) can help sensitize the machine to higher conductive metals under certain conditions, but makes the machine less sensitive to lower conductive metals. Manually adding to ground balance numbers (over-tune/positive bias) will help sensitize machine to lower conductive metals and less sensitive to high conductive metals in certain conditions. Hot rocks, cold rocks, charcoal turned into coke from old buried fire pits along with iron are potential issues for any detectorist. Ground conditions are the determining factor at the area of the site you hunt along with the metal you are seeking.
This would be an important concern for relic hunters and deep silver hunters, not a concern for general park, school or fresh water hunting.





I turn on iron audio and set iron discrim on 0. I have gone to many different sites around here in New castle pa and has ground balanced around 85-90
 
You certainly would know if you are over a metal target or not before ground balancing the way you are doing it. Here where I live, If I don't have a ground balance VDI in the 90s, I think there is something amiss. I do know I am in the middle of a mineralized "pocket" and depth is limited. It is what it is. The ATX is on my wish list.
HH
 
I just got an at pro today and was wondering if you have to constantly gb.


Only when your surface/ground type changes. I.E. going from black dirt to sandy gravel, Dry dirt to mud, Wood chips to dirt, etc etc. OR I have a tendancy to do it when things just don't seem right. And you'll get that feeling once you're used to your machine.
 
So just wanted to make sure that 87-92 is highly mineralized soil. And I should not expect to see coins past what 7, 8in in depht
 
Anybody else have a opinion on my high gb

Yes. Your number is high as others have stated, because you have soil with a higher ferrous content.. ie iron. I get the same numbers when I am detecting in central Arkansas where the dirt is often reddish color from the iron content.

You have no choice. It is what it is unless you detect somewhere else. Take your detector with you next time you go out of town and I think you'll find different numbers unless you happen to have similar soil conditions at your destination.

Now go out and ENJOY that new machine!

Papa
 
Yes. Your number is high as others have stated, because you have soil with a higher ferrous content.. ie iron.

You have no choice. It is what it is unless you detect somewhere else. Take your detector with you next time you go out of town and I think you'll find different numbers unless you happen to have similar soil conditions at your destination.

Now go out and ENJOY that new machine!

Papa


What he said. Mine here in Wisconsin is around mid to upper 80's. Nothing you can do about it. Oh, Moisture will greatly affect how deep you can sense things. Water is a great conductor. Spring and early summer is when I find my deepest things. At least thats what Ive found.
 
I was on another metal detecting forums. And some are saying that the high gb is not highly mineralized soil and some are saying yes. I read the link above and it was a little confusing but a good read.
 
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