[TowerTalk] Radial question

[jcjacobsen at q.com]

A question was posted regarding base loading coil on TBR-160: 


<snip> I note with interest a reference I remember from the manual for my old 
HF6V (the OP’s antenna is the HF2V, IIRC): in it, Butternut claimed the lumped 
inductance at the base of the antenna was not “base loading”.

But if a lumped inductance at the base of an antenna isn’t base loading, what 
is it? <SNIP> 
>From the DX Engineering site on the TBR-160: 


<SNIP> 
THEORY OF OPERATION The TBR-160-S functions as an inductive reactance in series with the antenna feedpoint, loading the antenna structure to resonance on the 160 meter band. 


<SNIP> 


Also, to get a better picture of how lumped loading works at different positions on the antenna, (base, center, top) I believe you have to look no further than the ARRL antenna book, or the Low Band Antenna book by ON4UN. Top loading is best. Efficiency drops as the load is dropped lower on the antenna. This is physics, after a fact of some sort. In other words, "it is the law". Just like gravity, you can't change it. 


73 
K9WN