I wanted to add a couple of points. As far as the volume of the signal being softer or fainter as the target gets deeper, this holds true depending on where your "Gain" setting is. the Gain setting runs up to 10 and at the lower settings, the deep targets will become lower in volume at a shallower depth than the higher settings. I have mine set at 6 and at this setting, a silver dime will remain a relativly loud signal until about 7 inches in depth. From about 8-10 inches the volume will be reduced so that the signal "sounds" faint. At around 10 inches, the volume doesn't drop anymore, but breaks up as the target gets deeper. If you run the Gain up higher, say to about 9 or 10, the target volume stays louder at the 8 inch plus depths, but the breaking up of the signal will be much more pronounced as a popping at the beginning or end of the signal. I like the Gain at 6, because where I hunt, I can readily tell the deeper, older coins and other targets from the shallower clad stuff and trash, by sound, without stopping to check the depth meter a lot.
The other point I wanted to make is when I look for a "Solid Signal", I also use the position and movement of the crosshair on the Smartfind Screen as a determinant. Many times on the deeper targets, the crosshairs tend to bounce around... sometimes only a little, sometimes all over the place. What I like to see is a crosshair that lands relatively close to the targets true ID spot with a little left to right switching with a slight downward incline towards the right side of the screen. Also, on the extremely deep stuff I look for when the crosshairs tend to stick in the right edge of the screen on most sweeps with the balance of the sweeps being around the target's true ID spot... this holds especially true with targets that have a large halo around them or are in very moist ground. On some real old and real deep silver dimes, the crosshair might actually want to lock on the upper edge of the scren 2/3 of the way over to the left side of the screen( where the "iron" targets would have read). The point of this is to use trial and error and a lot of attention to the crosshair position and movement to help you develop a good knowledge of the target's likely identity before you dig it up. This can eliminate digging most Iron targets and let you recover some other neat, non-coin targets like old gold jewelry, tokens, bullets and buttons, etc.
Take care and good luck, Mike.
