jim Jarvis wrote:
Who has experience with vertical square loops?
I hope you didn't want measured data.
Here is an EZNEC comparison between
(1) a vertical square loop on 40M fed at the center of the bottom wire,
with the top wire at 70 ft,
(2) a 2 element Yagi at 70 ft (the Yagi has a free space gain of 6 dBi),
(3) a 40M dipole at 70 ft, and
(4) the square loop fed in the middle of a vertical side
El angle Yagi Loop Dipole Loop fed side
30 deg 10.8 6.5 7.6 -2.0
20 deg 10.3 5.2 6.9 1.2
15 deg 9.0 3.5 5.5 1.7
10 deg 6.3 0.6 2.8 0.9
5 deg 0.9 -4.9 -2.7 -2.3
This should come as no surprise. The bottom wire of the loop is 33 ft
off the ground. The other antennas have all wires at 70 ft. Feeding
the loop at the top does not add any significant gain (maybe 0.05 dB).
Jerry, K4SAV
jim Jarvis wrote:
>JR's questions about loop v dipole has triggered a corollary question:
>
> Who has experience with vertical square loops? I used to
>regularly work a guy on 40 who used
>them with real advantage, versus my 2 el 40 @ 70'. At one time, I
>had his design notes, but I can
>no longer find them...and as far as I recall, it'd be an excellent
>antenna for my present location.
>
>N2EA
>
>
>
>
>
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