Evening star. [volume] (Washington, D.C.) 1854-1972, 1925-12-13
T.es of High-Frequency Circuits.

Practical uses of high-frequency CIR,
Cults in ong-distance TRANSMISSION ana
receptiOn have been made py Tue
Navy. the increase in traffic hanoieo
nv this method is pronounced as phe-
nomenal Almost every naval s'alioit
and a large number or NesSeiS iia'e
huil+ short-wave receivers so as TO CO.
operate with the Bellevue iaoola'oIS
in recention tests. Extraordinary re-
s,l,ts were secured in communicating
With the fleet in the distant Paclnc.
peculiar traffic on high frequencleS Is
now handled between Bellevue ana
stations in California. Canal zone;
Hawaii. Tutuila, Samoa. England anu
the fleet. During Macmillan Arctlc
exploration the Nays htgh-frequencE
circuit was used successfully.
Another function of the laboratory
NAV be the broadcasting of time sig
nails to scientists throughout the Worlu'
especially in the interest or estapisH
intI exact ATTITUDES and longitudes
In an effort to perfect the naval
radio service. particularly that afloat,
the Bureau of Engineering points out
the need of modern radio apparatus III
large amounts. The principal require
ments lie in equipment reliable for use
in battle-line communications nle
control work. particularly Tor alrcFdll
transmitters to replace spark sets. ana
more Select;ve receiving sets. Every
shin of the feet. it is held, should also
he provided with modern underwater
co,1nd receivers, and possible trans
ritters. which. while not strictly radio,
are operated by radio personnel aboard
ships. - -,
One of the limitations to progress IN
naval radio development seems TO lie
in the annual appropriations. when
have to be distributed economlcaHy
over the projects planned. NeFertne-
less, during the next lew years the
NAVY hopes to replace it's remaining
obsolete shark and arc transmitters,
both af1oat and ashore. with tube sets.
Incidentally it will equip each vessel
with more selective receivers. chiefly
to avoid interference with the puplc
broadcasting stations. few sets IN
use operate on broadcast frequencleS,
but they will soon be eliminated, as no
shin transmitters now operate on the
channels in the broadcast band.
Factor in Aircraft Service.
The Increased use Of aircraft with
the fleet has demonstrated that radio
communication is a most important
factor in this modern method of war
fare. and special studies to develop eff
cient and compact airplane sets espe-
cially for use in fighting planes are
under way. Another effort is directed
toward eliminating the interference
due to airplane ignition noises. which
limit transmission and reception in the
air. Among the things reported as &C
complished are two-way communlca-
ton for ships of the fleet simultane-
ously on several channels; duplex OPP
Grafton on four battleships, five cruis-
ers and an aircraft tender; submarines
now equipped with tube sets having a
range of $50 miles; all battleships and
cruisers operating on tube transmit
ters, and improved receiving appa.
ratus. Radio apparatus has been re-
placed or improved in most naval for
eign stations Economies include bet
ter communication facilities at de-
creased operating costs; p low-pow,
cred stations have been sold or trans
ferred; through standardization unit
| rost of equipment has been reduced
and certain salvage work has saved
| thousands of dollars.