On Tue, 11 Nov 2003 11:28:30 -0500, "Tarmo Tammaru"
wrote:
As for messing up the pattern, I
would think that in the majority of cases they want equal propagation in all
directions

That would certainly account for the term "broadcasting."

However, many, many stations use directional antenna systems (speaking
of at least the AM broadcasters) that change their pattern at
sunset/sunrise.

73's
Richard Clark, KB7QHC