Great post, Dennis. Was not familiar with Dick's work, but what you cite
is consistent with extensive work that N6LF has published on his
excellent website, which I have often referenced. Mostly that current
distribution affects LOSS, not directivity. But loss in the far field
certainly DOES affect directivity.
73, Jim K9YC
On 8/29/2020 5:44 PM, Dennis W0JX via TowerTalk wrote:
Unequal currents in 1/4 wave radials is to be expected primarily due to three
factors: 1.) varying quality of the ground under each radial; 2.) the effect of
close by objects such as buildings and other towers; and 3.) the variation in
the length of the radial wires depending on type of wire, insulation, and
construction methods. Effect on the actual radiation pattern depends, of
course, on the severity of the current variation and the number of radials
utilized.
Dick Weber, K5IU, wrote a very informative article in the late 90's which was
published in Communications Quarterly. He argued that 1/4 wave long radials
were the poorest length on could use.
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