I forgot to mention, the loop fed on the side is almost
omni-directional, within about 3.5 dB. The loop fed at the bottom has
nulls in the direction of the plane of the loop of about 9 to 16 dB
depending on the elevation angle.
Jerry
K4SAV wrote:
>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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