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Richard Clark · September 25th 06, 07:19 PM posted to rec.radio.amateur.antenna

On 25 Sep 2006 17:40:22 GMT, (John E. Davis)
wrote:

I am sure that I am not the first to create this simple antenna,
nevertheless a google search has turned up nothing similar. Have you
seen such an antenna before and if so, what is it called?

Hi John,

A Stub Fed Doublet. A Stub Fed Dipole. A Stub Fed Short Dipole. A
Stub Fed Short Dipole with End Loading. Take your pick.

The end loads can be removed and the stub lengthened to 18.5 inches to
re-obtain resonance at a higher Z to demonstrate two principles:
1. End loading increases current into the structure to lower its
resistance;
2. Stub tuning works.

Several comments. What's with the curious cogging of the SWR computed
from NEC2? EZNEC predicts a quite smooth curve. Your measured values
suggest nearby losses. What do you do to snub common mode currents of
the nearby transmission line that is precariously close, and co-linear
with the polarization of your vertical dipole?

73's
Richard Clark, KB7QHC