Judging by newsgroup postings, I'd say the most common meaning of
"takeoff angle" is "that elevation angle at which an antenna radiates".
For this to have any meaning, it's necessary to assume that the antenna
radiates at only one angle and no others. Since this is a false
assumption, the term "takeoff angle" as used by most amateurs is
meaningless. I've never seen the term in any non-amateur publication --
it seems to be in the same category as "capture area" and "S unit",
creations which only amateurs seem to have a need for.

As you say, it has a precise definition as used in EZNEC. The first
versions of ELNEC, incidentally, didn't report "takeoff angle" because I
thought it to be unnecessary to point out what anyone can see from a
glance at the pattern, and felt that the term would be misunderstood and
misused. Turns out I was right -- it's misunderstood and misused,
despite my best effort at explicitly defining it. But you've gotta give
the customer what he wants, not what he needs.

Roy Lewallen, W7EL

Cecil Moore wrote:
wrote:

TOA is deemed to be the angle at which maximum gain occurs.
Seems like you are fishing for something, but you will not get
it from me.


The problem seems to be that the definition of TOA is
not standardized. Literally, TOA can be any angle but
has a special meaning when quoting EZNEC. Neither my
antenna books nor "The IEEE Dictionary" define TOA.
I did a search for "take off angle" and "TOA" on my
ARRL Antenna Book CD with zero results.
--
73, Cecil, W5DXP