N2EA wrote:
>Anybody experimented or modelled with less than 180 degree
phase reversals? i.e. 90, 60, 30...and what happens with
vertical angle lobe steering?
Here are two KLM 610's at 1 and 2 wavelengths. These are
are old EZNEC models which are not as accurate as what I have now but
the relative change should be a reasonable indication of what happens
as phase changes on the higher antenna relative to the lower one:
Phase Gain @TOA` -3 dB at
0 16.85 8 4.0, 12.9
30 16.57 8 4.0, 12.7
60 15.72 8 3.9, 12.5
90 14.13 8 3.8, 12.6
120 14.25 20 15.3, 24.7
150 15.42 20 15.3, 24.6
180 15.84 20 15.1, 24.5
210 15.55 20 14.5, 24.5
240 14.55 19 7.2, 24.5
270 14.38 9 4.1, 23.0
300 15.86 8 4.1, 14.0
330 16.63 8 4.1, 13.2
360 16.85 8 4.0, 12.9
Maximum gain occurs at 0 and 180 degrees when the power is
concentrated into lobes at 8 and 20 degree TOA's. The other
patterns are smearing these two patterns together as phase
is rotated. Phase of 0 and 180 only leaves the hole between
12.9 and 15.1 degrees, but that could be filled by using the
lower antenna alone:
0 14.58 13 6.6, 20.8
73, Bill W4ZV
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