Chris, LA8OM, wrote, in part:
> I installed Sigma 5 on the ground in our garden last October.
> 1500 QSOs in last CQWWDX-CW contest. From my log
> during lunch break yesterday: VK2, FR5, VU2, V51. Genius,
> so small, simple and effective piece of equipment, this Sigma 5.
The Signal 5 is only 10 1/2 feet tall from the ground mounting
on up. Appears to be center fed, as a 1/2 wave antenna would
be. Note the horizontal elements at the top and a short ways up
from the ground mount stake. Are these intended to be RF electric
field terminations intended to nearly completely replace radials?
Radials must be used below 1/2 wave verticals to terminate
the electric field lines that come from the high RF voltages
at the lower end of the 1/2 wave vertical element. Lots
of RF current would be caused in the dirt without radials.
Is the short horizontal element near the ground of the Sigma 5
sufficient to recover 3 to 5 dB or so of loss which "ought" to be
experienced from such an antenna mounted "on the ground"?
Seems from this post by LA8OM to "work" well.
73, Jim KH7M
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