Rick,

Fan dipole with all the wires the same length....and closely spaced.
Resistance should be 2) unchanged as others pointed out. Coupling will
cause broader BW like a cage dipole. Unless your antenna conductors are
manufactured to limit variance.... Impedence in real world will be hard to
model in a bundle that has varying capacitance due to uneven spacing and
varying inductance due to twists and turns within bundle

I'll throw out a slightly different thought.

I think it would also model as a sleeve antenna.  That would make the EZNEC
model have only 1 dipole driven and all the other wires evenly spaced
around it potentially with small gap at feed point (that shouldn't be
needed since it's a zero voltage point).

At least, my mental model has them as (close to) equal. But my brain
wanders a bunch.

73,
Kirk KK2Z

PS: My favorite "work of art" sleeve dipole in one of the early antenna
compendiums was a vertical made up of a ring of resonators -- one for each
band -- around a driven vertical in center.

From: Rick Hiller <[email protected]>
To: BRAZOS VALLEY AMATEUR RADIO CLUB <[email protected]>
Subject: [BVARC] Antenna Theory Technical Question
Message-ID:
        <CABNEQE_mKnBH3if0mmvenpjopxJJf+c-ap=+eosvapc+vtd...@mail.gmail.com>
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I am in the midst of analyzing a Ham market HF antenna.  Still building the
EZNEC model, but working it thru the gray matter.

Case:  Take a 1/2 wl dipole antenna -- center fed.  Each side is made up of
multiple, equal length wires that are each insulated, parallel, and closely
spaced.  The wires are connected/common at the center feed point, but open
at the far end.

If, at this length, each wire's material DC resistance is 5 ohms....does
using multiple wires in parallel, as described above, 1) lower the total RF
material resistance, as resistors in parallel....or 2) does it stay the
same or 3) does it become additive?

Any comments would be appreciated.  I've got my hypothesis, but wishing
additional input.

Thanks and 73 ...Rick   W5RH
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