NEC-LIST: Ground Systems for Beverage Antennas - Errata

Hello Phil,

I guess one should read what one has written on a subject, when the
work was done some time ago, before recounting what one remembers!!!

Our initial studies prior to 1978 employed radial ground screens (at
both ends of the Beverage wire) comprised of 16 radial wires 50 feet
long, staked at the ends by 2 foot ground rods.

Later, when we constructed multi-element arrays, linear phased arrays
for transmit, and rosette arrays for receive; we employed smaller
ground screens.

The tabulated gains I sent yesterday were computed for a single
Beverage, intended to be used in a 24-element rosette array. At the
receive end the ground screen consisted of 24 radials 15 feet long; at
the terminated end, only 3 radials 15 feet long are employed, arranged
as "crow's foot" --- one radial pointing in the beam direction, and
one radial on each side.

Finally one more comment. Since you are concerned with receiving
rather weak signals on a frequency near 2 MHz, you could employ a
longer Beverage element; or a 2-element phased array. We were
concerned with the band 2-30 MHz. The power gain of a Beverage array
is increased (approximately) by 3 dB each time the number of elements
is doubled, The interaction between elements which limits achievable
efficiency has been determined --- interelement spacing can be as
small as 20 feet.

Jack

One More Reference:

H.H. Beverage and Doug DeMaw, " The Classic Beverage Antenna,
Revisited", QST January 1982, pp. 11-17 (a rewrite of Bev. Beverage,
2BML's QST November 1922 paper).

Both Doug and Bev are silent keys.

_____________________________________________
John S. (Jack) Belrose, PhD Cantab, VE2CV
Senior Radioscientist
Radio Sciences Branch
3701 Carling Avenue
PO Box 11490 Stn. H
OTTAWA ON K2H 8S2
CANADA
TEL 613-998-2308
FAX 613-998-4077
e-mail <john.belrose_at_crc.ca>
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Received on Fri May 01 1998 - 06:14:21 EDT