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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