Beam width
An omni sonar term, in plain English.
The angle the beam covers. The CSH-10 transmits 360° horizontally and 6° vertically; it receives on a 10° by 9° beam.
See it in action
The free lessons show where this shows up on a real screen: start with the learning path, try it yourself on the omni trainer, or look it up on real CSH-10 captures in the field guide. Owners and captains talk settings every day on the forum.