[laser188139]

Joe, I think I have seen weird behavior trying to create waterfall charts when some external noise during the measurement process, or some electrical noise in the signal, caused a glitch in the data. So you could try taking the measurements again, and see if you have the same problem.

You could also try using the Spectrum tab, setting the Mode to Spectrum instead of RTA, and take a real time measurement using pink noise to see if there are any obvious spikes at, say, harmonics of 60Hz. If you see these, some people with laptops have been able to fix these by taking measures on battery power instead of line power.

Bill

 

[laser188139]

Joe, here's another suggestion. Besides my unlikely suggestion of 60Hz harmonics, REW can get very confused if there is something like a static pop during the measurement. Unusually it figures this out and tells you it was a bad measurement. But this could also show up if you look at the Impulse graph. Does it look as if there were multiple peaks, equally loud? Or a later peak louder than the first? I wish I could make more specific suggestions, but I think I deleted the one or two measures where the Waterfall did not show anything. In my case, when I tried a second measure everything worked fine, so I discarded the first.

Good luck,
Bill