Did you try and duplicate that other guys video to see which nail positions would cause it to null? I am guessing that when you put nails around it as you did in a circle, the machine thinks they are mineralization and doesn't respond to them. Whereas, if they are on only one side or in a line, it's then that they interfere and mask the target. That is the only thing I can think of to cause that experiment to work and the other guy's to fail.
![Shrug :shrug: :shrug:](https://www.findmall.com/styles/smileys/shrug.gif)
I think the results would be pretty interesting.[/quote
I actually started with the in-line two nail test and it gave even better results than the circle in the video, I think the reason it worked so well was that I was using a pre 1947 UK shilling, these have a good silver content, doesn't work as well on modern coins but there again you can stick some of our modern stuff to a magnet.
I did the same test on a old florin and its was even better than the shilling but I only posted the shilling results as I felt that it would be a better comparison to the US silver coins, if I got it wrong let me know and I will try and get my hands on some silver us coins.
I still have more video, unfortunately I no longer own an Explorer so I cant do a comparison, however when I start going out with our club members again one of them owners all three Explorer models so it will be interesting to see how the machines compare in the field.
More video tests will follow and hopefully if the weather improves I will try a buried coin with nails and see what happens.