I'm not an electrical engineer. Just a guy who has hunted for 34 years. During that time, I have tried to learn all I can about the hobby and tools available. And, without a doubt, the best article I have ever read on ground balancing is entitled "EVERYTHING you wanted to know about Ground Balance", written by George Payne. His article points out that ground balancing a detector is simply another form of setting a level of discrimination. Because, in effect, adjusting your GB trimmer is simply an effort to discriminate out the ground! He explains the zero phase shift with ferrite and how ALL soil will always read more negative than ferrite. He explains why the internal fixed ground adjustment is calibrated using a dummy coil, not a real live coil. He talks about the difference in phase shifts of DD and concentric coils. He even addresses the ratio of the number of windings on the transmit coil compared to the receive coil. Like I said, it is an excellent article and well worth reading. You can find it online at
http://www.buriedcrap.com/buriedcrap.aspx?Object=Section&ContentID=56
HH Randy
http://www.buriedcrap.com/buriedcrap.aspx?Object=Section&ContentID=56
HH Randy