I compared the digital reading to another detector I have that will present the raw data or average the digital reading and as expected there is a cluster of numbers. It looks to me like the Explorer has reading that can be visualized as a cone. At the top, peak, would be a combination such as 7/25 and the next layer would be 7/26, 7/25, 7/24, and the next layer, 7/23, 7/24, 7/25/, 7/26, 7/27 as an example. The smallest square in learn would be the top layer, the medium box the next layer and then the largest box for the next to bottom layer. It appears there is a layer below that which is a default in that it is not reliable enough to process so it goes to default low iron. We construct the cone as the coil sweeps the target so can be unstable which is why we need to center the coil as best we can over the target for the best cone shape. The sweep speed is also a factor and may explain the way the