Well I am not to sure what to tell you about the coil however it seems that when I turn the detector on it will start jumping around finding "signals" in the air, the ground ect... I have tried going between different modes and the result continues. It first started on my third day in the same field where I am in Belgium, I did not have any problems for the first two days and i cant seem to think of anything to cause the problem between those days. I have tried cleaning the coil and removing it to inspect it but nothing physical stands out. More than that I cannot say, I was hoping this was an easy fix on my end but we will see.