I modeled a 160M dipole at 54' in EZ-NEC and compared it to the CQ
July 2001 article describing a 160M full wave loop 135' on a side.
At 20 degrees elevation angle (what info was shown) the two compare as
follows.
dipole -1.37dbi
loop -3.79 dbi
How is the loop beat a dipole on xmit?
How is an antenna that occupies a 135' square a physically better
choice than a single wire? Recall this thread started with the search
for limited space antennas.
de Brian/K3KO
Barry Kirkwood wrote:
>
> right!
> modelling such loops at 40ft or so shows that they are very good indeed on
> 20-15-10.
> the patterns have lots of nulls but these are not noticable in practice.
> they beat dipoles at the same height on the low bands.
> they hear very well on all bands with little rain static etc.
> ice loading can be avoided by choosing a sensible place to live
> cebik has good stuff on loops on his page.
> if you have the space and can do but one antenna the loop skywire would be
> an excellent choice.
> a smaller loop at say 40ft , worked as a toploaded vertical on 80-160 would
> be good. too.
> all this on the basis of personal experience of self and zl1mh.
> 73
> end
> Barry Kirkwood PhD ZL1DD
> Signal Hill Homestay
> 66 Cory Road
> Palm Beach
> Waiheke Island 1240
> NEW ZEALAND
> www.waiheke.co.nz/signal.htm
>
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List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
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supporting towers up to 96 feet for under $1500!! http://www.anwireless.com
-----
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