Sonar Technology A-Scope

The A-Scope is a real-time vertical bar that appears on the right edge of your sonar display. While the scrolling sonar view shows a history of what has passed beneath your boat, the A-Scope shows you what is directly below the transducer right now, at this exact instant. It updates with every sonar ping, making it the most immediate feedback your fish finder provides.

The A-Scope displays signal strength as a horizontal bar graph at each depth level. Strong returns like the bottom produce wide, bright bars. Fish appear as smaller bars at their respective depths. The length and brightness of each bar indicate the strength of the return, giving you a quick visual read on target density without waiting for the scrolling display to build an arch or mark.

Ice anglers rely heavily on the A-Scope because they are fishing from a stationary position directly over the hole. Since the boat is not moving, the scrolling display creates a static column that is difficult to read. The A-Scope, however, updates in real time with every ping, showing fish approaching the bait, the jig's movement, and the bottom — all in an instant-read format similar to a traditional ice fishing flasher.

Some fish finders allow you to display the A-Scope alongside the regular scrolling view. This combination gives you both historical context and real-time awareness, which is particularly useful when fishing vertically, jigging over structure, or sitting anchored in current while waiting for fish to move through your sonar cone.