Uhhh, programming, algorithms???
I have no knowledge of that Senator… LOL!

You guys are right: distance from transducer, location within the sonar beam, density of object and its size but let’s not forget the shape of the object and its orientation to the transducer. A Crappie that is on its side would reflect back more sonar than one that is swimming normally (body is vertical to transducer). Remember that the transducer is looking down from above which is why sometimes your jigs may show up and sometimes they won’t.