Evening star., 1926-10-17
NAVAL RADIO HOLDS
RECORD FOR POWERI
New Transmitter at San
Diego Has Sending Range
of 1880 Miles.

Special Dispatch 10 The star.
SAN DIEGO. Calf, October 16.z
A vacuum tube transmitter so times
ss powerful as the ordinary trans
n1itter in broadca sting station has
Just been installed in the Chollas
Heights Naval Radio Station here.
This sending vacuum tube radia tes
10000 watts Of electricity and Is said
by naval officials to he the most pow
erful tube transmtter in the world
1t is four times as powerful as any
other United States naval sending sta
ton.
This hroa dca sting device was not
designed for telephone use. but will
he employed for radio-telegraph com
munication. Nsing dots. dashes and
spaces. at rate Of 100 words a
minute.
Masts 600 Feet High.
Cholas Heights is remote control
station used by the Navy for sending
purposes only. The messages leave
antenna strung on three maxts which,
SOC feet in height. form riangle
1.l0n feet on each aide. The "crosS
arms" or platforms. at the top of the
masts arc SO feet long and contain
bridge on which electricians may
work. The actual sending is done from
the Port I.nma Naval Radio Station.
II miles distant across San Diego
and the hay hy air line. The Port
Iona key works the ChOllas Heights
sender while receiving is handled at
Port I.oma.
Six transn iiters are employed in the
station. The so .h00-watt tubes replace
200. .0n0-watt arc tranSmitters Under
@,y. .x-t1y
he able To communicate with Ameri
can ships in any part Of the world
during the night. when the station has
sending range Of $500 miles: during
the day II can span the continent to
Eastern points for about 5000 miles.
The set is operated from an alter
mating current commercial power sup
ply. by means of six 50-kilowatt recti-
fer tubes. which can deliver up to 100
kilowattS at u 900 volts Included is
0.000-volt master oscillator, which
excites eight 20.O00-volt amplifiers.
The approximate antenna current is
300 ampereS
The Significa nee of this station is
found In the declaration of radio Off
cials connected with it's construction
and operation that. II it proves com
pletely successful. as they predict 1t
large arc ira nsmitters such AZ are
employed by tho Navy at Washington,
d. G.; Honolulu and Cavite.
Japan Also Has Set.
The Chollss Heights set is one OF
three built recently by an American
company. a second was constructed
for the Japanese government. like this
in essential details. though differing
in some minor points. 1t has been
shipped to Japan. \ third was built
for use in South America, hut it is re.
ported lack of funds has caused II To
he stored at New York. where it had
been sent for shipment
The 30. .000-watt tube used at ChollaS
Heights is the largest vacuum tube
yet constructed for commercial use.
IT is SO large and becomes hot un.
der ordinary conditions that the cop
per plate used is water.conled Twen.
tv-two volts OF elect ricity are required
~ ''c T'n.r.~,> i, ,NeSe ti,hoG
Ths plates take from 800 to IL 900
N'nt>.
TranSmittpr Costs $40, 1000.
The new transmitter cost $50. 900.
ChollaS Heights Ststion WAS originally
constructed i'm 1915 80 y cost tf about
$3.50 900. Al that tine thnre was con
Sidera bile discussion concerning the To-
cation NJ the station. some maintain
ing that il should he located al River.
side. - miles r'her north from the
Mexican border. 1t is now located on
4 hill ~ miles from the center If san
Diego. With view of both mounta ms
and Pacific Ocean. The ,leavy towers
are capable Uf withstand .n@ a hori-
zontal safe pun "f % Geo pounds
Amateur hroadcAS;inc fans suffer H.,
interference from the station, accord.
ing To Navy officers. even when in the
Immediate vicinity of the station
Among other interesting facts, 30
gallons of water are required every
minute to keep the tubes cool. The
plate transformer weighs 4i2 tons,
cad the total weight of the set when
'acked is 5S.500 pounds.