>From: k6se@juno.com (Earl W Cunningham)
To: <topband@contesting.com>
>Date: Thu, 05 Mar 1998 16:08:04 EST
>
>Having read all messages which started with KZ5MM's noisy
>Beverage, it appears that the proximity (noise) problem
>(Beverage near Tx vertical) exists when the Tx vertical has
>elevated radials. Conversely, a Beverage seems to co-exist okay
>with a nearby vertical which uses non-elevated radials.
>
I can think of at least one good reason _NOT_ to run much of the
beverage near a transmitting vertical which is over ground which
has been improved with many adequately long radials.
Noise or no noise, beverages don't like really good ground to
work over. Hence their really poor performance when stretched
over salt water or reinforced concrete. So I wouldn't want my
beverage to be placed over the highly conductive ground around a
vertical with an adequate ground screen under it.
As a traveling wave antenna, the beverage really "wants" to have
fairly uniform (and relatively the poorer the better - up to a
point) ground under it for its entire length. A severe "bump" in
the ground conductivity under the wire will at the very least
destroy the non-resonant nature of the antenna. It will not be
possible to find a single load resistance that properly
terminates the structure for all frequencies. This may not be
terribly important if you are only interested in using the
antenna on one band. But the portion that is over high
conductivity earth will contribute far less to the enhancement of
low angle signals than the portion over average or poor earth.
>The N4KG feed method is interesting. I notice that if you
>remove all but one of the radials, it looks suspiciously like a
>half-sloper :-)
>
>73, de Earl, K6SE
>
Amen!
In fact, a good way to make the half sloper generate a nice
circular pattern is to feed two opposite pointing half slopers
from the same feedpoint. However, I have to admit that I usually
don't bother with it. I normally make use of the directivity.
Comes from being down in the lower left corner of the country I
think...
73, Eric N7CL
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