It's interesting how people's experiences differ, and how their perceptions
of how something actually works, and how a computer model calculates how it
should work. I have used MMANA-GAL to model designs, and it certainly helps
to quantify my measurements, and is a good start. "Your Mileage May Vary" is
a great disclaimer, after a system is described!
Also interesting is how DXing experiences vary from place to place, for
example Roger's situation where he has a high density of activity to his
east at medium range in Europe making difficulties, when he's looking for
other medium to longer range DX in NA to his west. Those in USA east have a
high density of local stations making it difficult to work DX. In VK/ZL most
of our wanted DX is quite long range, with very few locals. Consequently,
our receiving requirements differ.
My first DXing on 160 m was with a 160 m long doublet antenna, up about 20 m
supported by trees. That whetted my appetite for the band, and so I
constructed a top loaded vertical, over elevated radials. That worked, and I
made DXCC. Next, the elevated radials went (then kept falling down anyway!)
and I made the effort to bury 2000 metres of wire in 60 x 33 m radials. That
appears to work, but I have no way of objectively comparing the elevated
radial system to the buried radial system. But one aim of the buried
radials, was to have a non-resonant ground radial field, as I also run 80 m
over it. Next is to put up a 37 m high tower, so I have close to a quarter
wave on 160 m. That is my project for the Christmas break. I'm hoping to
have that up and running before the end of the summer DX in the mornings to
EU.
73, Luke VK3HJ
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