As can be seen by the fine data supplied, a horizontal loop and a horizontal
dipole have about the same take-off-angle.
Dave WX7G
On Thu, Sep 24, 2009 at 5:20 PM, Paul Decker <kg7hf@comcast.net> wrote:
>
>
> Hi John,
>
>
>
> Of course, higher seems to be better, and bigger also seems to be better to
> some extent.
>
>
>
> This might be sensory overload, but it does demonstrate what loop size and
> height can do to/for the loop.
>
>
>
> I did some modeling on this a while back over average ground, which seems
> better than what I have:
>
>
>
>
>
> 80 meter dipole at:
>
>
>
> 15 feet has - 0.22 dBi @ 50 deg, -1.53 @ 40, -3.47 @ 30, -6.52 @ 20,
> -12.15 @ 10 deg
>
> 30 feet has 3.78 dBi @ 50 deg, 2.57 @ 40, 0.73 @ 30, -2.24 @ 20, -7.83 @ 10
> deg
>
> 60 feet has 5.81 dBi @ 50 deg, 5.01 @ 40, 3.53 @ 30, 0.86 @ 20, -4.54 @ 10
> deg
>
> 120 feet has 5.29 dBi @ 50 deg, 6.66 @ 40, 6.9 @ 30, 5.47 @ 20, 0.82 @ 10
> deg
>
> 180 feet has -10.64 dBi @ 50 deg, 1.38 @ 40, 6.86 @ 30, 8.04 @ 20, 4.72 @
> 10 deg
>
>
>
> a full wave 80 meter horizontal loop at:
>
>
>
> 15 feet has -0.67 dBi @ 50 deg, -2.47 @ 40, -4.9 @ 30, -8.35 @ 20, -14.26
> @ 10 deg
>
> 30 feet has 2.94 dBi @ 50 deg, 1.54 @ 40, -0.79 @ 30, -4.17 @ 20, -10.03
> @ 10 deg
>
> 60 feet has 5.31 dBi @ 50 deg, 4.03 @ 40, 2.08 @ 30, -1.00 @ 20, -6.65 @ 10
> deg
>
> 120 feet has 5.14 dBi @ 50 deg, 6 .03 @ 40, 5 . 8 @ 30, 3.96 @ 20, -0.9 5 @
> 10 deg
>
> 180 feet has -10.66 dBi @ 50 deg, 0.87 @ 40, 5.88 @ 30, 6.65 @ 20, 3.06 @
> 10 deg
>
>
>
> three full waves on 80 meters, horizontal loop at:
>
>
>
> (NOTE: pattern has "gain" lobes at different take off angles need to point
> to right directions)
>
>
>
> 60 feet has 6.58 dBi @ 50 deg, 6.73 @ 40, 5.55 @ 30, 2.81 @ 20, -2.68 @ 10
> deg
>
> 120 feet has 5. 4 dBi @ 50 deg, 7.72 @ 40, 8.25 @ 30, 6.73 @ 20, 1.91 @ 10
> deg
>
> 180 feet has -10.33 dBi @ 50 deg, 2.5 @ 40, 8.3 @ 30, 9.41 @ 20, 5.93 @ 10
> deg
>
>
> using same 3x loop on 20 meters:
>
>
>
> 60 feet has 12.97 dBi @ 14.0 deg
>
> 120 feet has 9.01 @ 23 deg, 14.4 @ 8 deg
>
> 180 feet has 6.2 dBi @ 27 deg, 12.55 @ 17 deg, 14.6 @ 5 deg
>
>
>
> You can see that using the extremely large loop on the higher frequiencies
> has some serious advantages. The pattern isn't clean, but if the lobes are
> pointed in a direction you want, bonus!
>
>
>
> hope this is a little useful anyway,
>
>
>
> 73,
> Paul (KG7HF)
>
>
>
> From: John Geiger <aa5jg@yahoo.com>
> Subject: [Antennaware] Height for horizontal loops
>
> How high does a horizontal loop (the look skywire) need to be for decent
> performance? A quick google search revealed that people were running them
> at 25 or 30 feet with good results (in their opinion). I know that high is
> better, but how high does it need to be to show real improvement over a
> dipole?
>
> 73s John AA5JG
>
>
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> Antennaware mailing list
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>
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