My experience is very similar.
My 3/8 wave GP - 160 ft tower, 15 ft mast - is fed at 32 feet with 5
radials. I saw a very minor increase in signal with radial #4, none with
radial #5 checking with N6ND at 7 miles airline from me.
Performance overall is slightly below his phased 100 ft verticals. But not
much. As far as I can see, lacking a couple acres to turn into a sheet of
copper, ground radials aren't worth the effort for most hams in urban or
semi-urban areas with realistic land use limitations. Naturally, those with
property to burn, or an extensive ground radial system to defend, may have a
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