Topband: LU5OM shortened dipole (inverted vee) doing a nice job

[Steve Ireland]

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 at 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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