Thread: SI question from a newbie

It depends on model of unit and the frequency utilized.

With a Humminbird running 455Khz frequency....which is what most people use for searching...you can get a full 240' coverage to each side. Since you get a virtual 180 degree coverage both ways, the range is not limited by the water depth.
You probably wouldn't want to run that wide a range if you are trying to see fish, because even on a 11" unit, the fish returns would just be a spec. It is nice sometimes, however, to be able to run a very wide range to search for structure, creek channel edges, etc.
If you run the 800 Khz, the range is reduced, but typically you would be running a short range to try to see better detail if running the 800 Khz.


I will let the Lowrance guys chime in on their range as I am not sure what the beam angle is.

thanks Bob, I have a HDS 12 and HDS 9 touch.

Sorry.....

I get the best images with my humminbird 899 if I set my depth at 4 times the actual depth of the water is showing. So if its 10' then I set my SI range to 40-50 feet. If 20' then I do 80-100 feet. This way most things in the water are to "scale" and can be seen with greatest detail. You can go way further out than that, but wont be able to see near as much.