Hi Steve,
The answer is "it depends"
Beverage performance is ideal over poorly conducting soil and extremely
poor over highly conductive soil. In extreme cases. poorly conductive
soil creates a problem with establishing a stable and reasonably low
ground resistance at the feed point and at the resistive termination.
I was involved in operations of a massive array of 64 phased Beverages
installed (inland) on an island that is solid rock and a very thin layer
of topsoil. Ground rods were impossible. We used a chicken wire mat
at each end of the Beverages (similar to NC0B's use of chicken wire on
his verticals). The Beverages worked perfectly and all 64 had nearly
identical feed point impedance. We purchased two miles of chicken wire
from Sears!
The problems with using a single short ground rod is that its ground
resistance is a significant fraction of the 450 termination resistance
of a Beverage and its resistance varies with soil moisture content.
That's not a serious problem for a single Beverage, but its a big problem
for a phased array of Beverages.
My 8-circle passive receiving phased arrays are installed in a uplands
wetland. But the wetland sometimes dries out during a drought. Instead
of using a ground rod for each vertical I use eight 65 foot wires laid
on the surface of the ground. Perfect! Short radials should be just as
effective with a Beverage.
73
Frank
W3LPL
----- Original Message -----
From: "Steve" <k0xp@k0xp.com>
To: "topband" <topband@contesting.com>
Sent: Friday, March 8, 2024 4:32:21 PM
Subject: Topband: DXpedition Beverage Termination Grounding Schemes??
When on a DXpedition, and Beverages are quickly tossed and laid out
within several hours, how is the termination resistor "grounded" at the
far end, and the transformer at the near end; with counterpoises, ground
rods, or what?
And with either of those, how long and how many wires for the
counterpoises, and/or how many and how long the ground rod??
I've seen photos of expeditioners laying out Beverage wire through, over
and under thickets full of brambles and thorny bushes; but never have I
seen them laying out counterpoises or pounding in ground rods.
Curious Steve, K0XP
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