Evening star., 1932-03-27
TRAIN BROADCAST
PLANNED TONIGHT
Columbia System to Make
Test on Run Leaving Cap
itai at 9 O'Clock.

Engineers OF the Columbia Broad
casting System were faced with an in
teresting group of problems when it was
decided to undertake the first broad
cast of a complete program of enter
tainment from a speeding train. The
attempt will be made tonight from to
$50 o'clock aboard a Baltimore 81 Ohio
train running between Washington and
New York.
The prime requisite of the broadcast
was, of course, to construct mobile
studio capable of accommodating Jack
Denny's l2-piece orchestra, Bell Baker
and the other talent of the regular
Ever-Ready Radio Gaieties, the pro-
gram chosen for this experiment.
After a preliminary survey OF the
Baltimore g. Ohio road had been made
by both Columbia engineers ana rail-
road experts and the stretch between
Washington and New York selected, 1t
was necessary to find the railroad car
best suited for transformation into
temporary broadcasting studio. A regu-
lar Colonial type dining car was decided
upon. The car, cooled, equipped
with ball bearings rubber shock alb
sorbers and permanently sealed WIN
dows, was completely stripped and
treated acoustically with velour drapes
to reduce reverberation. The control,
amplifying and short-Wave transmitting
eouipment Is located in the kitchen
compartment of the car. Power supply
will be obtained from storage batteries
having a capacity in excess Of 1000
amperes.
Two Antennae to Be Used.
Two separate antennae have been
mounted on the roof of the car, pro-
ieeting at a maximum distance from it
consistent with restrictions imposed by
bridge and tunnel clearances-one for
transmitting the program to the two
pickup points located along the route
of travel, and one for reception OF IN
structions from the master control sta
ton at Laurel. Thus both a short-wave
transmitter and Short-WaVe receivers
will be carried on the train. The trans
mitter. experimental relay broadcast
station W2XDY, which will operate on
a frequency of 1912 kilocycles, Is a
direct crystal controlled model, employ
ing high percentage modulation and
operating on so watts of power. A spe-
cial antenna tuning unit, equipped with
a monitoring rectifier and a dummy
antenna, are included as an integral
part Of the transmitter. The receivers
are equipped with suitable wave traps
to insure proper reception OF tnstruc-
tions and cues.
Preliminary tests indicated the de-
STABILITY of two separate pickup points
to receive the program by short wave
direct from the speeding train. One
station is located at Beltsville, Md, and
the other at Laurel, Md. The master
control station has been constructed at
Laurel and the BeltsVille pickup will
be fed by special circuits to Laurel,
whence the program will be transmitted
over the Nationwide network, and also
to foreign countries over Columbia S
regular experimental Short-waye sta
tions, W2XE and W3XAU.
In order to complete the two-Way
communication between the moving
train and the temporary master control
station, the special experimental short
wave transmitting station, W2XDZ, has
been installed at Laurel. From here
the instructions and cues necessary for
the program will be transmitted to the
receiving sets aboard the train.
Leaves at 9 O'Clock
One Of the unusual features of the
broadcast is the Connie e-long copper
telegraph wire which will be used as an
aellal TO receive Tie Sl5ilhS sent Out
from the train. In addition to the
small antennae set up at both Laurel
and Beltsville, a carrier system has
been made available by terminating this
30-mile telegraph wire at both receiving
stations. Thus II the regular short
wave antennae fail to provide adequate
reception, the carrier system can be
used, Further precautions have been
taken by arranging the short-wave re-
ceivers at the ground pickup points
into a selective system; that Is, the
signals from all the receivers will be
carefully monitored and mixed at
Laurel. the master control point, and
, the best signal selected for transmits
sion to the Nationwide network.
Shortly before o'clock the train will
leave Union Station, carrying, in addi-
tion to representatives of the press,
executives Of the Ever-Ready Safety
Razor Co., officials of the railroad and
radio engineers and prominent group
Of Washington officials interested in
the scientific possibilities oftthis unique
broadcast,