The Beaver herald. [volume] (Beaver, O.T. [Okla.]) 1895-1923, 1922-12-21

is often used as counterpolse and
connection Is made with II by means
of a number OF copper plates or nm
interconnected network of wires, sunk
into the ground at various places with
In the area underneath the antenna.
These buried conductors should have
low resistance and should be put
deep enough so that the earth around
them Is permanently moist. See Fig
ure 10 for counterpolse OF this type.
The Beverage antenna Is one of the
most recent additions to the art OF
short-wave radio reception. Due to Its
characteristics. II was used at Ar
drossnn, Scotland. last December,
when 2S amateurs succeeded In brldg-
Ing the Atlantic with radio.
The Beverage antenna is adapted to
the reception OF signals on n single
predetermined wave length. II con
sists of one wire supported on 10 TO
J2-foot posts, this wire having n
gength OF either one or two even wave
lengths. If designed for 2OO-meter
reception, the wire will be either G,5OO
or 1900 feet long.
Unlike the customary form OF an
tennn, this wire Is grounded at both
ends At the far end, away from the
receiver, II is grounded through non
inductlve resistance of from $50 TO 400
ohms, and at the receiving end through
variable inductnnce. In the case OF
the receiver used at Ardrossan, five
stages OF radio frequency ampliiica-
tion, regeneratlve detector and two
stages of audlo frequency nmpllfca-
tlon were used.
AZ stated above the Beverage an
tennn is designed for reception OF n
single wave length, depending on the
length OF the antenna wire. If other
wave lengths are To be received the
length OF the wire must be changed.
IL has been found that the signal
strength using 100 feet OF wire, II
feet above the ground, is approximate,
ly the same as would be heard with a
single vertical antennn wire, 100 feet
I'm height However, the Beverage nn-
tenna Is highly dlrectonnl, and on ac-
count OF this fact, Interference from
directions other than those from which
one wishes To receive Is reduced to a
minimum. Also, due 10 the short dis
tnnce from the ground, static and at
mospherlc disturbances are almost
eliminated.
In general II may be said that the
Beverage antenna Is extremely well
adapted for the long distance recep-
tlon OF signals from given station
whose transmitting wave length Is
known.
Often by erecting an elaborate an
tcnna system, the amateur does not
get us good results as would he oh
talned from simple, well-lOcated One
The function OF an nntenna is to cut
the electromagnetic and electro-statiC
components Of the field radlated by
the transmitter and have induced In
II an electrn-motlve force which will
cause a current to flow in the nntennG
circuit.
The capacity and inductance OF the
receiving nntenna plus small amount
OF Jumped tnd"ctance In the station C
furnish drop to operate the recelv
Ing set directly or magnetic held e
transfer energy to second osclllat
Ing circuit should be equal to the nat
ural period OF the received wave
Roughly, the natural period OF single
wire antenna is 1.22 times the lengtl
OF the antenna proper, plus the lead
in. This natural of the antenna sys
ten should be, ns stated above, JUS
slightly less than the wave length oI
which reception Is desired. BY actua