Tdonaly wrote:
Cecil wrote,
EZNEC seems to model inductive stubs just fine so I have no reason to
distrust it. EZNEC fails to give the same results for an inductive stub
Vs a lumped inductive reactance because it doesn't model real-world
coils. It will not model Kraus' phase-reversing coil and gives erroneous
results when an antenna using phase-reversing coils is modeled. I have
the EZNEC files that demonstrate that fact if you would like to have them.
Cecil, you can't even give a coherent explanation of how or why Kraus
"phase reversing coil" works, or how it relates to Wes' work. I would
expect any coil would work between two half-wave dipoles, but maybe not
at the frequencies you expect, and certainly not just because Kraus
said so.
According to Kraus, his phase-reversing coil can be thought of as 1/2WL
of wire coiled into an inductance. Ideally, that makes the phase of the
current the same on both sides of the coil instead of opposite as it
would be if the coil was not there.
Tom, do you understand self-resonance? The coil between the two half-wave
elements must be self-resonant at the frequency for which the elements
are 1/2WL. A 1/2WL stub performs that function perfectly according to
EZNEC. But there is *NO* value of inductive reactance in EZNEC that will
produce the same effect as that stub. Would you like a copy of those
EZNEC files? Would you like for me to post them on my web page?
--
73, Cecil, W5DXP
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