Topband: Topband Digest, Vol 259, Issue 14

[Jim Brown]

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