I don't disagree with most of what you've said about actually getting
out there and building antennas. It's a huge part of the enjoyment I
derive from this hobby.
That being said, it's not easy to compare one antenna to another unless
they are up at the same time on towers separated far enough to minimize
interaction. And under the best of circumstances, antenna pattern is
difficult to experimentally determine. On the air performance is a nice
indicator, but unless you're willing to test a particular antenna over a
long period of time, propagation and other factors cloud the results
(witness some of the ridiculous claims for antennas on this and other
forums). Modeling with one version of NEC or other, taking into account
known errors and limitations, is (in my opinion) more likely to give
valid comparisons between various designs.
But the biggest reason I would urge anyone interested in antennas to
experiment with modeling is precisely because of what you learn. I have
been a ham for 40 years and have built almost every kind of antenna
except rhombics and LPDAs, but I learned more the first year I owned
EZNEC than I did the previous 30 years worth of experimenting. There is
simply so much information available from a model ... antenna pattern,
effects of phasing, current distributions on the elements, impact of
length and spacing changes ... that you can't help but learn a lot if
you make a point of understanding what you get. There isn't the same
ability to measure all those things (i.e., current magnitude or phase in
the top leg of a delta loop) in real life. If I build an antenna and it
doesn't perform very well, I don't have the same ability to figure out
why as I do if I am able to model it.
I just don't see the point of making it an either/or situation between
modeling and practice.
Kelly Taylor wrote:
> I'm not going to enter any debate on the merits of modelling. Like I said,
> if it's what you like to do, do it. But for those on the reflector who may
> have forgotten that learning about radio is part of what ham radio is about,
> go have fun with your antennas. Learn from what works and what doesn't. For
> someone who is still learning, it's the most effective way to learn, even if
> it's not the most effective way to get a killer antenna.
> 73, kelly
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