if the operator doesn't move the coil far enough off-center before pulling the trigger toggle into Pinpoint.
Also, they can all read incorrectly if the Signal Balance is not set at a point that produces a 'proper' Coin Depth Reading in the Pinpoint mode.
A good rule to follow might be to double check the coin depth reading before you start hunting a site, but after you have set the controls where you want them. That way, you will know that the particular coil in use and the Signal Balance setting adjusted will show a depth ox 'X' wover a coin on the ground that is a determined disytance from the coil.
If you toss a penny on the ground and, once ready to hunt, you try to Pinpoint it with the coil at 6" ... note the indicated coin depth and base your finds upon that. If a coil height is 6" but the Coin Depth reading says 4", then keep than in mind when inthe field.
Oh, another 'tip'. If you're not sure how 'deep' 6" is, just pull a $1, $5, or other bill from your pocket and use it. They are just slightly more than 6" in length.
Here's a third 'tip' to consider. Practice your pinpoint technique on a surface penny. remember to start with the coil's edge a few inches away from being in-line with the coin. Also remember to properly center the coil to get the most accurate Coin Depth reading.
If you control the coil's height so that the coil is 6" from the penny, adjust the Signal Balance so that you get a 'proper' 6" Coin Depth reading when you pinpoint.
Note that spot on the Signal Balance control. Then, when in the field, if you make a quick adjustment of the Signal Balance control to that setting if you are really that interested in getting a close-to-accurate Coin Depth read-out. When done, retunr the control to the seting you're hunting at.
Monte
