The evening world., 1922-05-24
ILLUMINATING STATIC WITH THI
p RESONANCE WAVE COIL.

Plans for the perfection of the ''reso-
nance wave coil method" recently
demonstrated In Chicago as a static
eliminator In radio receiving, and the
design of a standard instrument for
general use, are being worked out It
was announced by DIR. Louis Cohen,
Consulting Engineer of the War De-
partment, to-day.
At present this instrument is only
In the form of special laboratory appa-
ratus. DR.. Cohen pointed out, and as
such was demonstrated by him and
Major J. Mauborgu, Chief Signal Of
acer Of the 9th Army Corps Area In Chi
cago.
At the suggestion of Major Gen,
George o. Squier, Chief Signal Offlcer
of the Army. who invented wired
wireless" and method Of broadcasting
by that means on the lines OF electrical
power companies.' DR.. Cohen and Major
Mauborgue undertook a study of COM
bining their developments In the use
4 of resonance wave colls' With line
wire broadcasting with the result that
they found means OF eliminating o large
amount of the static ordinarily encoun-
tered For some time Major Mauborgue
and DR.. Cohen have been experimenting
with their resonance coils method used
in the reception and Transmission OF
radio signals. and upon combining the
theories Of Gen. Squier with their own.
were able to get most satisfactory re-
suits in eliminoting static interference.
A number of patents have already been
| filed on circuit arrangements for use
with wave coils by these experts. Com
menting on the recent experiments in
Chicago, DIR. Cohen said that two i'm
portant things were accomplished:
First, they broadcasted by means OF
.'~-t-S-5 wireless" on the mains or the
Edison company in the city OF Chicago,
plugging in transmitter on the hne
through condensers and sending with
q o-watt lamp. The messages trans
mitted were received at one point ON
the circuit six miles away from the
transmitting station and at another
point twelve miles distant. This was
the first time that a practical demon
stration of General Squiers line broad
casting system had been given In public.
second, messages were also received
from a distance ON the Edison system
it was said, showing that besides the
signals put on the circuit messages
sent from a distance could be received.
4 the city lighting circuit serving In the
place of an aerial. During the demon-
1 stration signals from Government trans
q mitting stations in Washington were
+ picked up and heard clearly. the Chi
e cago city electrical sytem acting as
. hugo receiving antenna.
In receiving by this method, Dr. Cohen
pointed out, the interference OF static
Is less, although much static Is still
Il present, but by connecting In the reson-
ance coils in combination with certain
circuit arrangements perfected by him
& and Major Mauborgue, II was found that
f the static was practically all eliminated.
The resonance wave coil method, he
added. had also been found applicable
for use as an ordinary aerial, through
experiments conducted last summer.
Describing the device known as reson-
+ ance wave coils briefly. DR.. Cohen said
that 1t was practically long coil. the
= length OF the wire used being compare
BILE to the length OF the wave which II
being received. The coil, which standI
vertical, is inclosed with short meta
tubss which slide up and down the col
and are grounded through certain circui