Air Distance vs Ground Balance Settings

[KVM2]

As I mentioned some place else, I pull and pop coils all the time. I use the 5.75, standard 8 by 9, and a clean sweeper.While the soil is pretty mild, it is of such a nature that coins are attracted to China....ie Go Deep.I want maximum depth, with out spending money on erotic coils because they are foreign..Monte mentioned ground balancing as being important..If I go from the 5.75 inch coil to the Clean Sweep, I can see 1.5 to 2 turns to get the same degree of neutrality. Holding up a bit,..I had a ten turn potentiometer put in to replace the standard Tesoro GB pot.. I don't suggest it unless you feel like a nut.(.I go from clay to a volleyball court and get lost occasionally).I turned the Vaquero GB pot totally to the left...That is the ZERO reading. And I measured the distance on the closest coin (on the floor) which happened to be an Indian.. and recorded the air distance results...Notice the lack of symmetry in the readings 0 to 5, and 6 to 11. Since air is reasonably neutral.I did expect the graph to be reasonably flat....The same number of turns in ground, even mild soil, should be more extreme in depth variations.(This is a WAG on my part only) Here are the numbers Zero, 7",,1-7 1/4".....2,,7 3/8 "....3...7 1/2"....4,,,7 3/4'...5,, 7 7/8 to 8.00"....6,,, 7 3/8 "... 7,,,7 1/4 ".... 8,,,6 3/4 to 6 7/8"....9,,, 6 1/2'... 10,,,6 1/4"....11,,,5 5/8"...So, these are just numbers, we'll get Monte to flesh them out for us.. If you can figure how to build a depth box with soil, it might be really interesting to do an air and ground comparison...I would expect the ground / coil distance to drop 20 percent....BUT would the curve be as flat???We don't know what we don't know, and that applies to metal detectors as well

 

[Monte]

I mentioned in my earlier response where I suggest some Vaquero and coin sample testing (Air testing with varied GB adjustments) it included two major suggestions.

1.. Test ALL coin samples, including lower-conductive 5

 

[tvr]

To get the absolute best "air test" comparison even eliminating the floor could be helpful, depending upon the make-up of the floor material.

Glad Monte addressed the floor as possibly contributing to the results. At my house, anywhere inside is a no go for repeatable air tests. Too much various conductive material too close to anywhere I might set the detector up. Too many nails in the floor. Too much interference from the wireless router and various wireless interfacing devices. I go outside away from wires with a large cardboard box. I set the detector on the box with the detector shaft parallel to the ground and the coil face perpendicular to the ground. Set up like that, I've been able to get air test results that can be repeated on different days. Inside my house, tests don't repeat well at all.
Cheers,
tvr