The Rock Island Argus and daily union. (Rock Island, Ill.) 1920-1923, 1922-08-05

ludt IL was VI Tue nature VI stdtlC
electricity. The hypothesis which
is the basis of our modern work is,
however. different.
I'VE imagine the other as a dis
turbed ocean with the waves Of
every length rolling in from all
directions. These waves are of the
same nature as the signal waves.
These disturbing waves which are
of different wave length from our
signals can be shut out by the same
means as we use for shutting out
other signals; that is, by tuning.
Disturbing Waves Come In.
But the disturbing waves which
have the same wave lengths as our
signal and in all respects of the
same nature pass through our tun-
ing system like the signal. We
must therefore find some other
basis for discrimination than wave
length.
If we can construct a receiver
which is sensitive only to waves
coming from one direction then
we can shut out waves from all
other directions, even if they have
the same wave length. This idea
started US on the work of directive
reception. Theoretically there is no
limit to the improvement attainable
in this direction. We might build
receiving antenna focused on
transmitting station in Europe, but
the antenna might be system of
telephone wiring covering the state
of New York.
1T is an attractive subject for
theoretical analysis, and it can, be
shown automatically how extern
sive antenna systems can be made
with unlimited directivity. The we'll
known loop vertical directive an
tenna' has a deaf ear in one direc-
ton, but receives signals and dis
turbances from three directions.
The wave antenna turns its deaf
eat to three directions and re-
ceives only from the fourth direc-
ton. For those who wish to unGer-
stand the characteristics of our
modern receiving system, in order
to make use Of it, popular ex-
PLANTATION may be OF some guild
ance.
Imagine the antenna to be a
long, narrow lake, and the wind is
the signal, and a cork, floating on
the waves that beat against the
shore, the detector. If the observ-
a. stands at one end OF the lake
he will observe waves beating
against his shore only when the
wind blows lengthwise of the lake
from the opposite shore. When or
the other hand, the wind blows
from his side of the lake the beat.
ing waves appear in the opposite
end, while his shore is calm.
! This, at least, would be the case
il the lake had smooth sand
beaches on which the waves would
spend their force. But, il it has
steep, rocky shores. the waves will
be reflected back and forth so thai
the whole lake will be rough. The
waves, which indicate the sigma
wind would thus appear at botl
ends of the lake, regardless OF the
direction of the wind. This mus
be avoided.
1.-THE wave antenna is therefor.
made with ends corresponding tt
the sandy beach. 1t terminates il
a resistance which is carefully ad
| justed SO that all wave energy i.
absorbed and none is reflected.
1.-THE practical advantages Of tn,
use of the wave antenna are: TIL
elimination OF something like 81
per cent of the atmospheric. dis
, turbances and the possibility o
concentrating all reception in ont
station. The developments which
have described show now that ,
practical solution has been foun'
for the atmospheric disturbance
in trans-oceanic communication
The same solution has been ap
piled to ship to short communica
ton, with the result thar the oceal
liners are in touch with our Cap
Cod station as soon as they leav
the English channel"
/ The stations from which the sig
mails to Riverhead are sent almos
continuously are Bordeaux. sendin
on $4,000 meters; Carnarvor
i Wales, 14,100 meters: Stavangei
Norway, 1900 meters; Nauen an
! Eivedese, Germany. 1850 and a.
i 700 meters, respectively.