Ok, I think I understand, you are trying to zoom a single frequency display without choosing the bottom zoom feature which splits the screen.
First choose the single frequency display that you want: HF or LF
Second, make sure you are using a manual range not automatic.
3rd, define the depth range scale of the screen that you wan: IE: 25ft, 50ft, 10ft etc.
4rth, the sounder display will not show the depth range that you chose above, however if you are in deeper water than the scale that you chose you will not see the bottom. That is ok.
5th-you a single finger and drag the screen up, this will allow the sounder to keep the same depth range scale but it moves that scale to a deeper depth with ever swipe up. All you have to do is continue to move the screen up until you reach the desired depth of water that you want to view using the depth scale that you selected.
If that is not it, please provide some more details, or provide a description of the competitors definition. It might allow us to get a better idea of the feature or function you are tryin to achieve. We apologize if our understanding is not what you had in mind. It can be hard to visualize the feature that you are looking for.
C-Bass
