I got an air test question.:help:

[Jessgo33]

Is it true that an air test is a esstimate? Meaning, a item in the ground will be detected deeper than in a air test. It this little bit of knowladge true? I saw on another form that an air test will be shollwer than a real object in the ground.

 

[azsh07]

You probably read it on a Minelab forum. The Explorer and Sovereigns generally will get more depth in ground due to the way their multifrequency GB operates.
For single frequency operating machines ( most all other machines) the opposite is true in most cases. There are exceptions due to extremely wet soil and the object detected but in all the time i have detected and tested .....I have yet to see any single frequency machine detect deeper than it can in the air and 99% of the time it is always less. Reasons are obvious why that is true as the ground is, of course, a taqrget which you filter out by setting the GB and it reduces the effect of any signal that lies within it....as a rule.
Ask any engineer who designs detectors and you should be hard pressed to find them say anything else...physics is physics.
Minelabs are an excepion ...I have owned quite few and love em...but they air test great and I have rarely seen em detect deepr in the ground....accept at the beach...then you can get some off the wall depth....also in wet soil they will again get depth that is equal to or greater than air. Now stick them out west in the dry arid soil with a little alkahli...and they get way less depth than air.

 

[deepnails]

Hello. Well in my soil in most places here in upstate New York almost every detector I've used detects far deeper in the ground than in the air. Almost every coin in the ground here has a corrosion patch around the coin, when I remove the soil I can see where the coin is before seeing the coin, I call this coin dirt. I've dug coins at rediculous depths which I won't mention because I don't want to here the greef. One way you can tell is when you have a slight coin signal and then after you disturb the dirt it disapears, this is because you have disturbed the halo so now the target appears much smaller to the detector. As far as Engineers go I grew up in a family of engineers and generally speaking they are great at design but not at use, many don't even have a clue as to the potential of thier machines, If you happen to have a GTI you can prove this to yourself. The GTI pinpoint mode will correctly ID a quarter well over twenty inches with no audio, the audio disapears around twelve to fifteen inches. Now the engineers told the garrett forum this is impossible, well thats funny because I spent five years and a couple of thousand hours using this tecnique a my old fairgronds and recovered hundreds of extremely deep silvers using this method. Now the old tr detectors will not generally goe deeper than an air test but in mild soil any vlf should detect any OLD target deeper than the air test. Good luck hunting, Darryl.

 

[Woodchuck]

I can by that in theory it sounds logical deepnails!