Air Testing Vs Ground Testing Coils Your Thoughts

[phrunt]

I think the more you know about how your detector works the more chance you have of success.   Time spent messing around testing and fiddling with things is never time wasted, it's just a method of learning.

Air tests are absolutely essential for working out Target ID's on VLF's, everyone knows that, some say the ID's in the air don't match the ID's in the ground, but for me they absolutely do, to depths some people can't comprehend as their soil is so different. 

Just because something doesn't work for you doesn't mean it doesn't work for everyone, that is the basic law of metal detecting I think, and often goes overlooked.  We are all right, but we're also all wrong, our soil conditions dictate everything so we shouldn't dismiss other peoples opinions so easily as wrong, they're often not.

Air tests for someone like me in what appears to be very mild soils are valuable but at the same time I understand they're useless to someone in more difficult soils.

[F350Platinum]

I haven't done much air testing, only once to prove a concept with a particular detector vs. 3 others, and sometimes after the find to verify an ID.

My thought is that i can quickly learn a new detector/coil by first digging pretty much everything i come across in each place until I am confident with how the machine responds in that environment. If I can make notes so much the better, I can remember tones and IDs fairly well. After a short period of time I end up digging more good targets than trash.

Notice I mentioned both new detector and coil.

I travel a bit (mostly coastal) and know that everywhere i go there are different conditions so I really have to start out this way every time, it's a discipline for sure. There will be variations with each visit as well depending upon ground moisture content, so what worked yesterday might not be as accurate today. I can tweak out a good program over time, and prefer detectors that let me save them.

I agree that all testing is worth something but would rather get out and get real time experience.

[palzynski]

A few years ago I was using both air testing and ground testing for my new machines . I have noticed that in mild / moderately mineralized soil and for a VLF detector ,  depth in soil = depth in air - 30% . This is a quite reliable formula.

For example , if you detect a coin at 40cm in the air , then you will probably detect it at 28 cm in the ground.  

But now I prefer to only do ground testing using my bed tests , see pic below. This is much more reliable than doing single air testing because this is much closer to real field conditions I think

 

Bed test - Testing the ML Eq 800 on a 10g coin at 11inches depth :

[Quick]

Air tests?? Is that where the invisible nuggets are found??

[PI-Man]

Ugh been busy last 2 days on chores and repairing a Sovereign.  Hate when that gets in way of detecting.  Everyone has great explanations and thoughts — the videos and picts help us all.  Helps people expand on their ideas and share.

Quick

That made me choke on my water when I read your comment.   That was the laugh I needed today.  Always like humor.

[Ogliuga]

On 12/11/2022 at 3:08 AM, midalake said:

I keep air-testing simple! I want to know the maximum performance of a detector and that is what air-testing accomplishes. Then the goal is to see how this performance can translate to the ground/beach. 

If you take for example a pulse, an ATX or TDI or other P.I and do an air test, you’ll never know the effective power of the machine until you swing the coil above the ground...unless you want to check if the machine is on or off. This is why I think air tests are totally useless. 

[GB_Amateur]

While reading this thread I started wondering if generalizations that people are making apply both to IB(aka 'VLF') and PI types of detectors.  Then I read the first link that Steve H. posted (second post of this thread) and got the answer.  If you are curious about this topic and haven't read Steve's long post, you are missing something, maybe a lot -- as was the case for me.