Shortwave Radio Listener (SWL) Antennas -versus- Amateur Radio Antennas
In message , Dave
writes
Telamon wrote:
In article ,
Dave wrote:
John Smith wrote:
However, in side-by-side comparisons on 10-6-2m antennas I have
built, comparing a 5/8 against the 1/2 (construction
methods/materials and matching components identical) ... the actual
difference, in the real world, must be less than the width of a
meter needle in the readings ... or, put simply, I no longer deal
with the extra length required of the 5/8 ... your mileage may vary ...
The advantage of a physical height (antenna length) between 180 and
215 degrees (see previous post regarding the magic number being
around 195 degrees) is improved take-off angle and reduced
skywave-groundwave interaction, not dramatic nearfield voltage increases.
Regarding Mr. Smith's comments above my experience and others is the
opposite. 5/8 is a much better performing antenna than a 1/2 wave for
local VHF and UHF communications. Well worth the effort to build a 5/8
wave antenna over a 1/2 wave. The 5/8 had some kind of series load
coil part way up the whip where the 1/2 wave match/compensation was
done at the base so the whip was solid. Sorry I can't more specific
then that as those experiments were many years ago.
Mr. Smith is still lost in space.
5/8 wavelength antennas do not require a ground plane, do they?
Oh yes they do.
--
Ian
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