Discussions like this wax and wane with opinions... However there is actual
data to work from..
The easiest to understand is the work of Rudy Severn, N6LF (do a web search)
His field measurements (not theory, not done on a computer, but actual dirt
under the finger nails data) show that for a small number of radials - 4, 8, to
maybe 12 - that making the radials resonant by shortening them untill they are
resonant - which will approximate 0.125 wave - increases the vertical antenna
performance considerably... However, by the time you hit 16 to 24 radials that
effect is diminished and you are better off with longer radials in the 0.18 to
0.20 range... When you hit 32 radials you will do slightly better with 0.25
wave... By the time you get past 50 radials you will be better served with
longer radials up to roughly 0.4 wave....
Now, in the real world, not everyone puts up a vertical and installs a full
radial field immediately... So, to get up the antenna and get on the air ASAP,
I suggest 8 radials at 0.125 wave... This will allow you to make some
contacts...
Then when you come back to add the next 8 radials I would make them 0.18
wave... After that I would add 0.25 wave radials until I hit 50 radials...
Above that number I would add 0.4 wave radials... In the end you have a blend
of radials of varying length...
OTOH, if I were able to lay down a 100 radials immediately, they would all be
0.4 wave
denny / k8do
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