While searching some ancient bench gravels with the GPZ 7000 in the Arizona desert today, my ears were met with a broad, mellow reversed signal from the wireless speaker. I took off six inches of soil with the pick, and the signal was a little stronger. Changing from High Yield / Normal to General / Difficult resulted in a fainter, but normal signal response...definitely a metal target and not a hot rock. Putting the coil on edge produced no discernible signal; all of this information together t