Hi Bill,
Yes of course they radiate, but consider the field strength
underneath a ground plane consisting of a solid metal disk
versus the field strength underneath a sparse 2 radial
counterpoise. In which case do you think the field strength
underneath the ground plane would be greater? Now
connect the dots along that continuum. As the wire radial
system starts to approximate the continuous shield (e.g.
the solid disk), the field strength underneath the radial
system will start to drop. This is why an extensive radial
system reduces earth losses for a ground mounted vertical.
The radial system shields the lossy ground from antenna's
field. If it did not, then RF currents would continue to be
induced in the lossy earth underneath the radials causing
RF energy to be converted to heat.
73 de Mike, W4EF................................
> If more radials helped, that's good, but it's not because of any
> *shielding* effect. Radials do radiate - they're part of the antenna
> system, after all.
>
> If you have symmetrical radials, the radiation tends to cancel in the
> FAR field, but the near field radiation will be quite strong from each
> individual radial.
>
> As always, use whatever works. :-)
>
> Bill, W7TI
>
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