repost from main board

[arca54]

I am posting this here too any thoughts from you guys

I have an eagle 320 on trolling motor and a480 on the console
My question is do any of you get the images of fish arches like they show in the ads?I go out and adjust mine every way i can and have never read anything like that,I can find brush and other cover but can never really say i see anything as fish for sure.Am i adjusting something wrong if i turn sensitivity up i get dots and lines but no arches.Thanks for any ideas
(pic is from ad)