Detection distance, ground vs air

[Nexus]

Would you please specify that beyond? I noticed only discrimination just above ferrous and unknown GEB.

The GEB on Nexus can never be unknown as it will not work on ground, so i can assure it is very well known.
That beyond refers to the fact that finding coins near Iron or below Iron does not require small coils, but coils with very fast time constant.
I can easily repeat my MBNT with 20" concentric coil with the same success.

So the theories about the old detectors been better on MBNT than new detectors are not as folks believe.
It all comes down to how fast in actual fact any detector is and fast have nothing to do with the electronics. As I said many years ago everything begins and ends with the search coil design in the induction balance detectors.

[Koala]

Ok guys. So many great opinions on the subject. Please tell me what effect is the one you see on the video below? Coin been detected louder in the soil than it is in air with the same settings.
Watch carefully from 7.05 to 7.18

Several in our club have the NOX. Finds no more than any other detector on most fields and I am being kind here.


The NOX does seem to do as well or better on fields with a lot of coke in it

Real fields with real settings there is very little between any detector.

Not sure why but on light fluffy ploughed and disced my old 1265x is normally towards the high end of finds rate.

Doesn't do well if the land is waterlogged

[Koala]

Or this instead.

At least the latter is a test that everyone can do, where the same can not be said for your example unless you are prepared to ship your Iron wedge and mineral dirt over and over. Cheers.

not sure what I am looking at here. Turned up the volume. with the first coin there's only a couple of directions that would be diggable if you were listening with headphones plus with so little discrimination you would dig every iron Thats bent or circular. Horseshoes plough shear and large flat iron would all sound better than the first coin.

not say the detector is rubbish just the video in my opinion doesn't show it in its best light.

[Koala]

Interesting video. It seems to confirm the idea that VLF detectors [in general] have less detection depth in the soil when compared to an air test.
I'm not sure why the Nexus would show the reverse, unless the coil balance is being affected in some way by the soil matrix, but I'm guessing you already know the answer. Hopefully you will share it here.

plenty of videos of the NOX showing the opposite.


to many variables. But suspect a piece of coke or iron near by.


Occationly I find targets below there normal air test depth. Not often maybe once or twice in a couple of thousand hours detecting. The ground is a jumble of 3D artefacts. Somehow they line up to boost a targets response.

[Koala]

not sure how we got here

does air tests reflect in ground depth.

mild soil yes

the more mineralized the ground the more you loose

[Koala]

air test have to be realistic though

rapidly waving a coin backwards and forwards isn't the same as moving a coin across the full width of the coil plus a bit, and a true sweep speed.

ideally on a wooden stick although I have found no difference using my hand.

[Nexus]

not sure what I am looking at here. Turned up the volume. with the first coin there's only a couple of directions that would be diggable if you were listening with headphones plus with so little discrimination you would dig every iron Thats bent or circular. Horseshoes plough shear and large flat iron would all sound better than the first coin.

The first coin is a hammered gold 1.5 grams only. If you are to reject the mentioned Iron slabs (circular, flat ect) there will be no chance left for finding any small gold coins, period.
On the other hand there is not one other detector that can repeat this demo with such a small gold coin.

[pustareka]

http://kladoiskatel.net/blog/Glubina...a_tablica.html

[Mehranfar]

Nexus standard se

[Mehranfar]

Nexus standard se

[Mehranfar]

[aft_72005]

please upload circuit diagram and sprint file .

[Mehranfar]

please upload circuit diagram and sprint file .

Nexus file gerber file.zip
gerber file

[aft_72005]

Nexus file [ATTACH]n427533[/ATTACH]
gerber file

Thank you .