G'day from West Australia! Conditions in the last week have been
frustatingly poor, in particular to Europe. The one bright European spell
came on 10/10/97 when GU3WHN was a solid RST559 on 1.828, calling CQ DX but
being called by Europeans. C'est la guerre, I guess.
I've been playing around with an inverted-L (66' vertical, 66' top, 50
radials 30 - 70' long (8' high) plus perimeter wire in a W3ESU/K8CFU
'mini-poise' format) for the last couple of weeks, which has been
interesting to compare with the performance of Mike VK6HD's inverted vee at
70'. The inverted-L appears reasonably efficient, with a Z of 29 ohms as
measured on an Autek RF-1
After listening to what Mike has been working/hearing versus me, I am still
unconvinced of the merit of predominantly vertically polarised antennas IF
YOU HAVE POORLY CONDUCTIVE GROUND on 160m, particularly if you mainly
operate around sunrise. For those 'little pistols' like me can only get
something up between 40 - 60' off the deck and with poor ground, I am of the
opinion that a dipole, even if bent into an inverted-u or v shape may be a
better all round antenna than an inverted-L.
The inverted-L does work quite well and is superior out to K1ZM at sunset
here, a very long distance (and a man with a great vertical array!)
However, after sunset, Mike can work stuff I can't even hear - something
that happened rarely with my old inverted-U dipole (132' horizontal top, 66'
semi-vertical section at each end) at about 50' high.
This situation is even more marked at sunrise, when having a good high angle
radiator here seems to pay dividends. Mike has copied FH/DJ2BW at RST 559
when I can't hear a thing on the inverted-L. Although he hears better than
me even when I have the dipole up (less noise at his QTH) it is not that
marked...
At sunrise, VE1ZZ who is usually the same strength as the majority of
Europeans on the dipole is several 'S' points down on them when I use the
inverted-L.
None of this probably sounds very scientific, but is based on 'feel' and 25
years-plus interest in the low bands.
I thought it might help some LF DXers who are on sand, rock or gravel soils
and soldering on with inverted-Ls that will never work that well because of
poor ground conductivity outside the Fresnel zone of the antennas (i.e
outside of their earth mat).
Sometimes a good low horizontal can be better than a good high vertical -if
your soil is poor, maybe most of the time. My bent low dipole has got me
over 90 countries on 160m.
73,
Steve, VK6VZ
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