[TowerTalk] vertical antennas math & 1/2 waves

[Jim Reid]

> >DXer screws around with 1/4 waves.  A 1/2 wave is already
> > resonant and doesn't need any more help in that department.
>
> Maybe it is because 1/4 waves are half as tall?

And,  because half wave verticals have very INTENSE
E fields at the base of the vertical,  they still need LOTS
of radials!  As WWVH learned out here on Kauai.  See:
http://www.boulder.nist.gov/timefreq/images/radiostations/
wwvh-large/wwvh5.jpg  .

15 MHz antenna array. Two half-wave vertical dipoles separated by a
quarter-wave length and driven 90 degrees out of phase to direct
the signal in a cardioid's pattern to the West.  Note the large number
of radials on the ground surface; several easily seen passing under
the fence in the foreground.

73,  Jim  KH7M



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