I bought the iceducer for my Elite 4 and took it out for a shake down run a couple days ago. Seems to work well, but one thing I noticed that can be annoying.

When jigging or when reeling in and stopping, I will have a line show up on the graph. It will slowly and steadily rise to the top of amplitude scope in a perfect line, and when it gets to the very top of the graph, will stop. It shows up every few minutes at most.

Anyone had this issue before? It's hard to describe, and I didn't get a picture. If I have to illustrate it I will.

The shape of the sonar pulse is like an inverted cone. It is the size of the transducer at the transducer and larger as you get away from it.

As you reel in, your presention has less coverage. I would guess when it stops drawing the line, your presentation is not directly under the transducer.

Just the way sonar works. 

No this is not losing image of my jig. It's still on the sonar when this happens. But a line will show up from time to time that will make a perfect line as the image scrolls, from the bottom or randomly in the middle while jigging. It's like a return, but it just rises slowly and steadily to create a perfect line.

Sonar records echos from stuff that reflect the sonar pulse.

You may have fish following your jig as you move it, they create lines on the display also.

Air/gas bubbles reflect sonar pulses too and would be recorded on a slanted line like you jig does since the depth changes as the screen scrolls.

Not a fish, that much i could see. It also wouldn't stop if i had been reeling up, just keeps going. Bubble i could believe. I'll have to try and pay more attention and see if i spot anything.

Bubbles: