I'm hoping someone can enlighten me. I frequently see Yagi antennas mounted
on commercial buildings. They are usually relatively simple, probably mono-
band units, aimed at the horizon. What's puzzling is that many of these
tend to be polarized *not* vertically or horizontally, but at a 45 degree
tilt! Can anyone explain that?

(I know nothing about the specific busineses or the purpose of the antennas,
so I can't speculate about what's at the other end of the radio signal).

Bob, KI8AB

(remove 'duct tape' to respond)