Depending on time of day, different bands perform differently! If the bands look quiet (daytime), change the waterfall “view” to “Weak Sigs”. My S-Meter is calibrated and you’ll notice it doesn’t change when you change the waterfall view. At night, the waterfall might look better set to “Strong Sigs”. The point is that signal strength changes with the atmosphere and unlike tuning a radio, you’re looking at a big slice of RF spectrum – so it will often look different during the day vs. night. (Even winter vs. summer!).