air test vs ground

[chuckaaron]

I've always been told that with certain detectors (eg. sovereign)that even thou it air test rather badly--it did much better in the ground.
One english web site disagrees--
(http://www.garysdetecting.co.uk/hoard_test.htm)
Any comments?

chuckaaron

 

[Rick(ND)]

I took a quick look at that site and what I seen was not a good test as the ground was disturbed and air was introduced, so that will affect the outcome of that test. Now in a real test is what it will do in actual hunting I feel and those that know the Sovereign knows what it can do. It will detect a coin much deeper in actual ground than a air test will.
Some will have some different ground too that will affect the depth too in actual hunts, but up here in ND we have seen 13-14 inches with the Explorer using the 12 inch Sun Ray coil and I got my deepest coin a Barber quarter in the same hole with a buffalo nickle with the 12 inch Sun Ray S12 coil at a 13 inches too, but it was very iffy and not your classic signal. You have to know your detector and go slow to hear these.

 

[UK Brian]

I think your misreading the report. The important thing is that the Minelab does not lose much in-ground depth. Other machines will air test at much greater distances but the drop off in in-ground performance is much greater ie in my near twenty year old test bed a coin the Sovereign detects at 10 inches in air can just be detected at 8 inches in the soil. A leading other brand scrapes 13 inches in air (so three more) but hardly gives an audio indication at seven and a half. In real life detecting you could say you would only pick the coin up at seven at the very most. So there's a one inch difference in the Minelabs favour.
The other consideration with the Sovereign is not to air test in auto as not seeing any minerals it reverts to a mid sensitivity setting....in the ground you can pump and ground balance to ensure the best performance.

 

[chuckaaron]

thanks for your comments.

chuckaaron

 

[UK Brian]

One other thing Chuck
Most detectors have sinusoidal coil drive so iron minerals on land or black sand on the beach weaken the detection field. Pulse machines on the other hand have their sensitivity increased.

Brian