> I need information (pref. www links or other sources)
> describing
> short monopoles using multiple wires connected to it's top and fed in
> phase for increase in radiation resistance. (Used in LF/VLF).
>
> Get yourself a copy of the RSGB booklet :
> Practical Wire Antennas
> It is excellent
The VLF antennas with multiple tuned drops never worked as claimed,
and gradually were abandoned over time for more simple setups that
produced higher efficiency. One example in the NE USA even made
engineering textbooks when the system had significant FS increase
when they went from multiple drops to a single normal top-loaded
vertical.
Coaxial Inverted L's, multiple drops, and other fancy gimmicks do not
lower noise or increase efficiency over a single wire the same
dimensions. It is all in the minds of the beholders.
Ian, G3SEK, informed everyone in a similar discussion some time ago
the RSGB has corrected their Handbook regarding radiation resistance
of short monopoles. The RSGB Handbook no longer makes the incorrect
statement that adding drop wires increases radiation resistance and
ground system efficiency.
I'm not familiar with the booklet Practical Wire Antennas. Like our
Antenna Compendium, it might be technically unedited or lack
technical peer review processes. The problem is always sorting the
good information from bad information in non-peer reviewed technical
publications.73, Tom W8JI
W8JI@contesting.com
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