On 7/28/2024 2:03 AM, Tom Boucher wrote:
Sorry Jim K9YC but it is incorrect to say that a loading coil at the base
of an antenna, which is less than a quarter wave, will affect the high
current point of the antenna. Assuming the coil is pure L with no
distributed C, the current exiting the coil will be the same as that
entering it.
This is an Alice in Wonderland statement -- most practical loading coils
DO have distributed shunt capacity between turns. And yes, that is the
simplifying assumption in the model. But it is part of an antenna, and
currents in any antenna are complex, needing both magnitude and phase to
describe them. And phase is established by the boundary condition, which
is the open end.
73, Jim K9YC
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