I am new to detecting and currently using normal and only 2 tones.
Here's my theory/logic for coin hunting:
Have you ever found a coin or other small object? I'm sure you have. How did you pick it out of the pile of dirt or sand that you just dug up? You many have got lucky and saw the object and picked it right off the top of the pile. If not, you might have used a secondary pinpoint device to find the object quickly. If you had to find it by hand, how do you do it? I think most people split the dirt in half and test one pile and then the other to eliminate the pile that had no tone and keeps the other. It's only logical to keep splitting the pile of dirt in half until you have narrowed it down to a handful that contains the object you are looking for. Even then you sometimes have to keep splitting the handful of dirt in half until you narrow it down enough to find that little object.
So......
I look at the entire ground the same way. I have to keep splitting it in half until I find what I am looking for.
On the E-Trac I have 35 FE levels and 50 CO levels on the screen which totals up to 1750 possible grid coordinates. That is a lot of possibilities. How can I split that in half and in crease my odds of finding what I am looking for?
I need a way to narrow down the 1750 possibilities into a more manageable pile of dirt.
The 2 tone Ferrous setting does that for me. In TTF mode everything from FE 1 to 17 gives me a high tone and everything from 18 to 35 FE gives me a low tone. I have, in essence, split the ground in half by splitting the screen in half. Now I have eliminated 900 low tone possibilities and kept the 850 high tones for further inspection. Sure, more experienced hunters may be able to pick out some foreign coin out of the lower numbers, or the anomaly that tells them that there is a good US coin amongst that bad tone area. I am not that hunter. I have to increase my odds as much as possible and play the percentages.
So now my pile of dirt has 850 possibilities. Of those, I need to narrow it down some more to increase my odds even further. How about using the E-Trac emulator and documenting all of the valid signals for US coins? Seems like a logical thing to do since that's what I am looking for.
OK, done. Now I have narrowed the 850 possibilities down to about 110. That's a good split of the pile. If I'm a little more liberal in my ranges maybe it's only 200 that will yield what I want.
So that's my logic. The normal two tones helps me split the dirt from 1750, down to 850, down to 200. Time to dig and start splitting the dirt even further.....