"I fail to see what comparing one less than ideal antenna to another
less than ideal antenna proves, except which one is a less efficient
antenna." [W8JI]
For most people living in sub quarter acre lots - and for lucky ones like me
on half an acre - far away from salt water, all our 160m antennas are
relatively inefficent compromises. The best antenna is the most efficent
one. Like most radio amateurs, the actual area I can put up antennas in is
limited - for example any earth mat has to fit in a space about 20 x 30m -
which is still more room than many urban amateurs would have.
>" What I am trying to say is that under some poor ground conditions, a low
> horizontal is a better - more efficient - low to medium angle radiator -
> than a vertical." [VK6VZ]
[Answer from W8JI] "I understand where you are coming from Steve and I agree
with you, but I
think many conclusions reached on the way to this truism are wrong. I think
the only reason you favor a horizontal is your yard is so small that you
have no choice. Now it could also be your soil is worse than Georgia, which
is about the worse in the USA and that you indeed do have very poor low
angle performance with a vertical even on 160. What IS your soil
conductivity in VK6 Steve?
"I suspect the ONLY way a low horizontal (over a typical range of earth
types) could be a more efficient radiator than a vertical of any modest
height would be if the efficiency of the vertical was pathetic. It isn't
that the crappy soil would make the dipole good or the vertical bad at 20
degrees, it's just that the lack of a good ground would murder the vertical
at any angle LESS than it would hurt the dipole."
[Final word from VK6VZ] Tom's last point may well be true - and is really
the point I was trying make. I wasn't saying my dipole was an efficient
radiator, just more efficient than any vertical I can put up on my half an
acre of poor soil.
However, I do know how to make a earth system (confirmed vertical user for
low band DXing for 27 years) and an aerial with a vertical component does
actually work for me from this QTH - I have had excellent results with a
half sloper, a top loaded vertical (40' high with massive umbrella capacity
hat) and quarter and 3/8 wave inverted-Ls amd worked many stations in Europe
and the USA with them. The first two of these antennas were up at the same
time as my inverted-U dipole for several months and were - most of the time
- either equal or an 'S' point or so down on the latter. Just occasionally,
on certain paths (east coast USA), they were better.
Verticals worked better for me for DXing on the low bands for every QTH I
lived at in the UK, even ones with only a few radials - but with the
exception of one QTH here in VK6, they have performed worse than horizontals
- a terrible shock!
My explanation for why things do what they do - those truisms - come from
reading books and from well travelled people like you, Tom, and W4ZV and VE3BMV.
The only reason I e-mail this stuff to the reflector is to show that you
don't need a big vertical with lots or radials to work DX on 160m - you need
an open mind and a willingness to try aerials of vertical, horizontal and
mixed polarisation and see which works best FOR YOUR PARTICULAR QTH AND ITS
SPACE LIMITATIONS.
If you are lucky enough to have room for both a horizontal and a vertical -
that's even better!
Vy 73,
Steve, VK6VZ
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