W8JI said:
>How do we explain the results of VK3ZL and ZL3REX, and other
>VK's and ZL's over the years, who are neither over good soil nor
>near the ocean, and who also are south? Some of the biggest and
>most consistent signals over the years on 160 from VK and ZL
>have come from verticals, or antenna with significant vertical
>component.
VK6VZ said:
G'day Tom and all
Greg ZL3IX and I covered the situations of ZL3REX and VK3ZL in earlier
e-mails and their success is explainable by higher latitude/better soil
conductivity and better soil conductivity respectively.
However, what success has been experienced by VKs in other states is
neither here nor there. In terms of distance alone, comparing VK3 to VK6,
for example, is like comparing operating from GA to operating from CA!
With regard to the area of VK6 I live in, with its latitude/power coupling
situation and rocky/gravel, I was attracted back to 1.8MHz in 1995 by the
the operations/encouragement of Mike VK6HD and Kev VK6LW. Both stations
had tried a variety of vertical antennas, including shunt-fed towers, and
settled on mainly using inverted vee dipoles around the 80' mark (which was
as high as they could get them).
Mike VK6HD - like me - has an inverted vee dipole at around 80 - 90' high.
He also has a 'vertical antenna' in shape of an inverted-L with an 80'
vertical section over a ground screen consisting of 132 quarter wave
radials. Like me, particularly within an hour of sunset or sunrise, his
inverted vee dipole is by far the most useful antenna.
My other inspiration was Bill, VK6AS, who used a full-sized quarter
vertical, over 60/132 (I forget which) quarter wave radials. However, Bill
was located right by the sea, at Esperance,on the south coast of WA and
around 700km east of me. As I said before about the power
coupling/geomagenetic latitude in WA, it does JUST favour vertical antennas
- if your ground conductivity is good enough! - and Bill's success proved
this.
W8JI said:
I honestly think it is more a matter of clutter and interaction near
>the antenna than "ionospheric antenna coupling" or ground
>conductivity.
>73, Tom W8JI
VK6VZ replied:
My inverted vee and Marconi-T antennas are sited at right angles to each
other, on the same tower, to minimise interaction - as are VK6HD's
antennas. A couple of years ago, Earl K6SE kindly modelled for me the
configuration for the lowest possible interaction that was possible on my
property and the antennas have been erected in this configuration. In
practice, there is hardly any shift in resonant frequency of one of these
antennas if the other one is removed.
Their performance is also as different as chalk and cheese.
At this point, I'll rest my case. If I win the State Lottery, if you've
got the time Tom, I'll pay for an airline ticket and you can come stay with
Deb and me, listen on the radio to my antennas and we'll have a round-table
with some of the other topbanders so you can hear this stuff first hand.
Vy 73,
Steve, VK6VZ
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