Earl and all,
I found my actual Delta loop dimensions...140'7" for each side
and 243'7" for the horizontal leg. At 6' above ground, this resonated
at 1830 kHz. I found EZNEC's results were resonant at a significantly
different frequency (>50 kHz I recall), so you either need to scale
them in EZNEC to resonate at 1830, or you need to find EZNEC's resonance
of the actual physical dimensions...I attributed this to modeling
errors...but the pattern and gain comparisons to a vertical over the
same ground, etc should still apply. Supported from the 175' level of
my tower by ropes, the vertical tips were about 60' apart and about
130' high I recall.
Maybe this is another case of modeling not representing the real
world accurately since I am convinced my vertical is the better antenna...
so much so that my loop is now collecting dust in the barn! I will also
hasten to add that it served me very well for 2.5 seasons at both NC QTH's.
W3BGN's loop is a killer and W2GD's has won the CQ 160 Multiop several
times the past few years so they are a very good antenna as proven by
results (not rhetoric, models, etc).
73, Bill W4ZV
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