I think I understand your question here. High Trash with the CTX is a mode you use to hunt that has a narrower
channel/more disk/ than just your coin mode. You can use either ground coin or ferrous coin option in the High Trash Mode.
As for the rusty nails, some will hit where pennies hit but if you look closely, you will see a lot of scatter around it when it is
on 12/34. Most of the time if you move from a north to south position over the target to an east to west position (1/4 turn over the target)
you will loose it or it will be very faint if it is a nail. Hope this helps.
channel/more disk/ than just your coin mode. You can use either ground coin or ferrous coin option in the High Trash Mode.
As for the rusty nails, some will hit where pennies hit but if you look closely, you will see a lot of scatter around it when it is
on 12/34. Most of the time if you move from a north to south position over the target to an east to west position (1/4 turn over the target)
you will loose it or it will be very faint if it is a nail. Hope this helps.