Evening star., 1924-07-12
SH0RT-WAVE TESTS
IN ELABORATE WAY.
Westinghouse Company Ex-
periments With Broadcast
, Equipment at Heavy Cost.

Electric and Manufacturing Company
has completed and has been operating
some months now new specially
designed radio experimental building,
erected at a cost of several hundred
thousand dollars.
The new building is one-story con-
crete and brick structure located on the
Greensburg pike, about a mile east OF
the Westinghouse companys East Pitts
burgh works. The site chosen is within
a few feet of being the highest spot IN
Allegheny County, and is one of the
level spots available on the hills which
dot the locality.
The new site of the shortwaVe sta-
tions of KDKA is in direct contract TO
its former location, where despite some
known drawbacks, transmitting With
Hastings. Neb., and England was car
ried on nightly. When first installed the
short-wave transmitter was located on
the top of a nine-story building directlS
in the heart of the East PlttSourgh
works Steel buildings, known to have
decided absorbing effect on radio waves,
completely surrounded the set anu III
addition. it was located in valley Win
hills on three sides. AS mater OF
fact the main transmitter of kDkA Is
still located in the same place, ana IL Is
a matter of radio history that all OF
kDKA's transmitting achievements nave
been accomplished from this set how
ever, there is a probability that the a2e-
meter transmitter will be moved TO thls
very desirable new location.
Apparatus Placed Symmetricaily.
The new radio experimental building
has been SO designed that all apparatus
contained within it is located symmetrl-
cally with respect to all other apparatus
The basement is divided into sew
in
chamber contains the high-poweI
transformer plant, motor-generator
sets, filters. chokes and other apra-
ratus One of the rooms contains
transformer station of the Duquesne
Light Company. The remainder OF
the basement is occupied by the oat-
terry room, furnace room and storage
space Power is brought into the
basement through underground ducts
from two separate sources, ooth OF
which are 4,000-volt, three phase, SIX
ty cycles. This current supply may pc
stepped up or down as required. Inc
available power supply is In the
neighborhood of 250 kilowatts, which
be necessary.
With this basement arrangement
all bulky apparatus is located out OF
the transmitting room and is never
in sight.
The main apparatus room on the
first floor of the building, in which
are located the oscillator modulator
and rectifier panels, is large and spa
cious and having windows on all four
sides is well lighted by day.
Rectifer in Special Frame.
The rectifier which furnishes high
voltage to the plates of the water
cooled tubes is mounted in special
ly designed frame so that every part
of the apparatus is accessible Re-
placements and observations can be
conveniently made because every
part of the unit is in full view of the
observer. The rectifier has a ca.
pacity which can be pushed to $50
kHowatts, if it were necessary, and
is the result of the several years ex-
perimenting and pioneering of the
Westinghouse Company in .short-wave
broadcasting. The rectifier is of the
three-phase type. having a tube on
each side of the line or total of six
Ater cooled rectitier tubes In front
of each tube is a helix of rubber tub
to cool the tubes On the front of the
panel is row of knife switches used
$ to regulate the voltage of the trans
formers. thus governing the output
The oscillator panel is of the same
general construction as the rectifier
panel and makes use of Westing
house, high-power, water-cooled am
beranode transmitting tubes. These
are not ordinarily subjected to max
imum capacity, but are usually paral-
leied. Thus each tube is subjected to
about half its rated capacity and
an unusually long life in tubes re
suits. Another reason for paralleling
tubes is that operating on the high
frequency waves causes unusual
stresses and strains to develop not
encountered in the ordinary radio
casting wave lengths and some safety
factor is desirable. Immediately be-
hind the tubes is the tuning induc-
tance. In the front of the panel are
AS in the case of the rectifier every
part of the oscillator panel can be
observed and replacements made
without difficulty. The modulator
panel, using the same general type
of tubes, has switching arrange
ment whereby the number of tubes
used and the amount of power used
can be regulated. Indicating meters
are mounted on the front of the
panel and there is also a modulation
meter which shows how strongly the
energy generated by the oscillator is
being modulated.
Location of Control Room.
Adjoining the main room and ex-
tending a few feet into it is the con-
troll room. The front and extended
sides of the room have glass windows
so that every part of the apparatus
room may be constantly seen by the
operator. This room is equipped with
two units, one using five-watt tubes.
the other using fifty-watt tubes. The
start and stop control switches, line
terminals, amplifying connections,
etc, all are located in this room. Thus
the engineer at his desk can con-
trpl everything in the station. He
also can listen in and hear the sig
nails. thus judging them for quality.
Other rooms on the floor include
the main office, sleeping room and
shop.
One of the most distinctive marks
of the station is the extremely unique
s4ortwave antenna, special type
Perfected by Frank Conrad, assistant
chef engineer Of the Westinghouse
CSmpany and the man who made
most of the present records possible
through short-wave development.
The antenna is a copper tube erected
v&rtically with respect to the ground
and supported from pole about fifty
feet high. The antenna, which has
a tball on it's one end. is quite rigid
I'd prevent it's swaying. Extremely
fine results have been obtained from
this perpendicular type of antenna
Though only one is now installed
there will be several erected at va
rfDus points about the station to take
advantage of the directional effects
p@ssible through the different loca-
tibns.
High Recording Results.
Wonderful results have been OBJ
tained from broadcasting from the
nSw site of the short-wave station
Al an example, 1t is only necessary
I'd state that daylight transmitting
was successfully carried on between
Tits station and KFKx, at Hastings
NIB, in order to repeat from Hast
irfgs the Republican convention pro-
ceedings at Cleveland and the Demo.
cratic convention proceedings at New
York. Such a feat Of daylight broad.
casting would not have been believed