G’day
One of the great myths about 160m is that low angle radiation is always needed
to work DX on the topband. The other is that almost any kind of vertical
antenna will always beat a relatively low (in terms of a wavelength) horizontal
one for 160m DXing. It all depends on where you live.
The best advice I was ever given on antennas was by Les Moxon G6XN, who
suggested that some locations predominantly suit a particular type of
polarisation and one should always try both. Even better, if possible, have
both a horizontally polarised and a vertically polarised antenna for your
favourite low-band – and switch between them regularly.
In Western Australia, our ground conductivity is so poor that on 160m even
vertical antennas over as full-size ground screen lose so much signal in the
far-field that a ‘cloud-warmer’ dipole under a quarter wave length high will
outperform them. This situation isn’t helped by the south-west of WA having a
geomagnetic latitude that suits horizontal antennas at least as well as
vertical ones.
Mike VK6HD, Western Australia’s greatest topband DXer with around 260 countries
confirmed, found a simple inverted vee dipole about 100’ high generally
outperformed his quarter-wave inverted-L with an 80’ vertical section over 132
quarter-wave radials.
Similarly, in VK6 I have tried a heap of different vertical antennas, over a
variety of high-quality elevated and buried radial systems, and have always
come back to using dipole antennas, of a similar height to that used by Mike
and my friend Phil VK6GX. In my case, this has resulted in 236 countries
confirmed.
If you have losses in the far field from poor soil conductivity, all the
radials in the world and a full-size vertical can’t fix this. ;-)
Vy 73
Steve, VK6VZ/G3ZZD (topbander since 1971)
I wondered about the inverted-L. My guess is that it had a poor ground
system.
73, Mike
www.w0btu.com
On Jul 17, 2017 9:22 AM, "K1FZ-Bruce" <k1fz@myfairpoint.net> wrote:
There are always exceptions.
A few years ago there was someone that had a inverted V that worked well
for DX.
It was found that it was feed with open wire feeders that acted as a
vertical antenna with top loading.
If your antenna works well be happy. Ham radio is a great hobby.
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