Evening journal., 1921-09-09
RADIO EXHIBIT
At STATEFAIR
Hundreds of Callers Enjoy
Sensation of Using Wire
less Telephone
PLAY MUSIC THAT
CAME THROUGH AIR

One OF the most interesting ex-
hibits at the State Fair this year is
that OF the Delaware Radio Associa-
ton. 1t is not only interesting in it.
self, but is to a large extent a reve-
iation to the people OF Delaware,
most OF whom are probably unaware
Of the progress made along the line
OF radio communication in this
State.
In the course Of this week many
hundred Delawareans enjoyed the
unique sensation of listening to
voices transmitted for miles, without
wire. and themselves talking with
persons at other stations.
The exhibit was frightened by
continuous music which was trans
mitted by radio from the residence
OF Harry Beeson, at Bellefonte, Dell
and was amplified through a loud
speaking horn for the benefit OF vis-
itors.
The exhibit. which is located un-
der the grandstand in the automo-
bile section. consists Of a complete
Transmitting and receiving cabinet
made by the De Forrest Company
and rotary gap XIV. spark set,
and three stage amplifier receiver,
used in connection with the spark
set
The De Forrest cabinet operates
as easily and efficiently as land
wire telephone by merely connect
Ing one wire TO an aerial another
D, a., o1ortrio Tirbf cooirof apd
grounding a third. the speech being,
II anything clearer than the latter.
This set carries the voice currents
up to large aerial located on the
roof above the grandstand from
which they are spread in all direc-
tons through the air. 10 be picked
up by a similar aerial at stations
within the radius of 40 to 100 miles.
The tuning OF this apparatus to
receive communications from dis
tant points is a simple matter. and
the voices can be heard with all the
distinctness Of an ordinary tele-
telephone.
The spark set already mentioned.
consisting OF a XIV. transformer.
furnishing 1000 to 10000 volts.
discharging through a rotary spark
gep furnishes the vibratory cur
rents which are led up the aerial
wire and -adiate out into space for
reception at other stations.
This spark set is what Is ordi-
narily known as wireless telegraph.
and communication instead OF being
by the voice is accomplished by the
t1Sa ~ tho Tptarpotforof NJ. ~
graph Code of dots and dashes. This
is the type Of apparatus which is EN-.
ployed to the greatest extent at IN,
present time. although il is gradual,
being replaced by the wireless tele
phone. such as the De Forrest SCI
already described.
The wireless telegraph. however
IS still the principal means OF COM
munication used by ships at sea. and
also in sending press dispatches
broadcast such as the Naval News
Service which is sent out from the
high-power wireless station at An
napolis Nd, every evening to all
ships within a radius of 5000 to 1000
miles. The wireless telegraph is also
employed to set ships chronometers
or clocks and gives the official
Greenwich time twice a day from
the Naval Observatory at Washing
ton.
The Delaware Radio Association
exhibit also includes receiving sci
consisting OF an ampliher used ir
connection with the wireless tele,
graph apparatus already described
above. BY means OF this instrumcn
1t is possible to detect and magnif,
the impulses coming down the aeria
from distant stations. This appli
ance may also be used in connection
with a wireless telephone and result
in a tremendous amplihcation OF IN
sound at the receiving point.
Wilmingtonians will recall tina
this device was employed success
fully at the .Aidine Theatre durin
the Dempsey-Carpentier fight las
July
William Osmond. Willard Wilso
and Fred Gooding are in charge q
the Radio Association exhibit at tn
fair. and have been courteous in eS
planning the radio appliances to tn
many Interested visitors who stop q
the booth. All three OF these mem
bers have wireless sets OF their owl
The association is an unusually az
tive group OF men interested in th
advancement OF radio communities
ton. Mr. Osmond is president {
the association, and the other on
GERS are Fred Gooding. treasure
and f. NJ. Symmes. secretary I'll
membership. although not large.
growing steadily, and the state hs
already gained a considerable shar
Of prestige in this line of activit.
due almost entirely TO the efforts {
the association. Meetings are hel
twice each month. al which the La
est developments in radio commun
cation are studied.