Evening star., 1933-03-10
TESTS AT AIRPORT
TO Be IMPORTANT.
Dial Telephone Remote Con.
troll System Among New
Developments.

Washington- Hoover Airport soon will
become the proving ground for i'm
portant new developments in the opera
ton. of Federal airwayS communication
aids, involving remote control by a dial
telephone system of the airways
weather broadcasting station near
Camp Springs, Md, and the radio range
station at Hunters Point, Va. and the
transmission of weather maps by
teletypewriter.
The Department of Commerce is
completing construction of a central
control building at the airport which
will house all local airways commune
cations services, sound-proofed broad
casting room, weather map receiving
equipment and remote control switch
boards for the Maryland and Virginia
radio stations.
Though the building now is nearing
completion, the installation of equip
ment may take some weeks, since neceS-
sary testing work will be carried on as
the installation proceeds and some
changes may become necessary.
Remote Control Model.
The local station eventually Is ex-
bected to serve as the model for remote
control of radio facilities at about 10
locations throughout the United States.
The Capitalization of control will pro-
mote efficiency and is expected ma
terially to reduce the cost of operation
and maintenance of the vitality i'm
portant aids to air navigation.
It is necessary to locate the weather
and beacon tranSmitter stations some
distance from the airport SO that
antenna towers will not be hazard to
.Rirplanes landing and taking off.
Central control from the airport. how
ever, has been found essential, espe-
)Dially with the new system Of trans
going into operation.
The equipment to be installed In the
tnew control station at the local airport
twill include machine switching ap-
NparatuS operated by a telephone dial;
a monitoring system showing the
operator which transmitters are in
operation; radio receiver giving both
visual and aural indications of the
quality of broadcast signals and opera
tion Of the radio range; speech equip
ment which amplifies the microphone
energy so that it can be transmitted
over telephone wire to the broadcast
transnlitter; high frequency receiver
for reception of communications from
aircraft in fight; batteries, charging
equipment, and line equalizers. All
this equipment is to be inclosed in a
SOunGprOO1 room 10 prevent noises IN
the station and those from the airport
landing area interfering with trans
mission.
Teletypewriter Circuit.
In addition, the station will be con-
nected with teletypewriter circuit and
equipped with one or more machines
for reception of hourly weather mes
sages and for the teletypewriter maps.
A duplicating outfit will be installed
for making copies of the weather maps.
All equipment will be operated from
the station through telephone circuits
and dial-telephone controls, which will
enable 18 different operations to be
carried on by dialing. To care for
additional operations the apparatus to
be used will have a capacity of 100
different operations, each of which may
be controlled by dialing only two
numbers
Such functions as warming up the
radio tubes of the transmitting station,
putting the station in readiness for use,
cutting the radio range off the air,
shutting down the broadcast station
and restoring the range station to
operation can be performed by merely
dialing the proper numbers. The
operators also will be able to control
the red obstruction lights marking the
radio towers miles away by the dialing
Of numbers which turn them of or on.