Randy Lake wrote:
>So if one was to have the choice of an inv.v at 95' or a delta hung from
>the same support which would be the best choice for dx?
>73, Randy N1KWF
>
>
----------------
Here is a comparison between an inverted vee, apex at 95 ft with an
included angle of 120 degrees, compared to an equilateral delta loop
with apex at 95 feet (which makes the bottom wire at 9 feet) and fed at
the bottom corner. Broadside to the antennas, the delta only has 1 to 2
dB advantage for very low angles (less than about 7 degrees). The
break-even point is 11 degrees elevation. Above 11 degrees, the
inverted vee wins big time. Off the ends of the antennas, the delta
loop, in the direction opposite from where it is fed, has a little more
gain than the inverted vee off its ends. I think the inverted vee is a
hands-down winner, for all purposes, when the choice is between these two.
Note: An inverted vee with an included angle of 90 degrees loses about
0.6 dB compared to one with 120 degree angle, but it gets the advantage
back when looking at the gain off the ends of the vee.
There are some other choices of shapes that I think will beat an
inverted vee at 95 feet for DX, such as a rectangular loop (100 ft x 45
ft) fed on the side, but these are hard to support from a single tower,
and so, may not be a fair comparison. You didn't ask for comparison to
other choices.
Jerry, K4SAV
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