"Ted Jensen" wrote in message
...
Does anyone know where I can obtain a plot of the antenna pattern for
a major (50,000 watt) commercial broadcast station?

www.radio-locator.com

Note that the maps are careful labeled "for entertainment purposes." They
are not totally accurate,a nd very,very, very exaggerated. On AM, the only
useful contour is the innermost circle... and it is actually bigger than
reliable reception areas really are in most cases. The outer two circles are
totally meaningless.

This only assumes you are in the US, one of few places where "major" and
"50,000 watt" are synonymous.