Let's design a short antenna just for fun
On Wednesday, November 5, 2014 10:56:53 AM UTC-6, John S wrote:
Hi, Gentlemen -
What if we (just for fun and knowledge) design a short dipole antenna
together here in the group? How short should we go as a practical matter?
* What would be the worst input impedance we would would wish to deal
with? That will actually determine the shortness of the dipole, yes?
* There will be losses. How much are we willing to accept? This is
another determining factor to the shortness, yes?
* What might be the best feed arrangement for our short antenna? There
are lots of ways.
I don't know much about small loop antennas, but I can fade into the
shadows and try to learn from you.
Any other suggestions to this endeavor is also fine. Let's just discuss
what we enjoy doing. If you have other topics of small antennas, let's
put them on the table.
Gentlemanly arguments are welcome concerning the technical aspects of
our discussion. I have never had a problem with anyone who says "I
believe you are wrong in this assumption and here is why."
Thanks, Gentlemen.
Cheers,
John KD5YI
In very general terms, I would design a small dipole the same as
I would design a mobile whip. Except I would have two of them
back to back. The design would include all the usual considerations
about loading coil location, top/end capacity hats, etc.
What is good for the car, is good for the house.
I have plenty of old software, much from Reg EdwardsSK, that can be
used to design the antenna, determine appx losses, determine the
number of turns for the loading coils, etc, etc.
And then use EZNEC or whatever modeler to test the final design
before going out to the garage to whip up the actual antenna.
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