Evening star. [volume] (Washington, D.C.) 1854-1972, 1930-08-30
MORE S 0 S WAVES
DESIGNATION URGED
World Distress Radio Cover
age Advocated by Naval
Authority:

Adequate radio coverage' for vessels
plying the Pacific and other remote
waters by the designation of interna-
tioral distress fraquenciees in the short
waves to augment the present 500-kiloL
cycle Internationally recognized S o S
wave is advocated in a statement by
Capt. S. G. Hooper. director of naval
communications.
In discussing the existing condition,
Capt. Hooper declared there are areas
in the Pacific so far distant from shoce
stations that the signals transmitted on
the intermediate channel of 500 kilo-
cycles cannot be heard during daylight
because of the variable conditions gov
erni1g the carriage Of radio impulses.
These conditions are at their worst dur
ing the daylight hours when the maxi.
mum coverage on the 5N0-kilocycle
channel is in the neighborhood of 500
miles, he said.
Ia the face of this, he declared, a
vessel in nljdPacifs. approximately
5000 miles from anywhere might
never be picked up by shore stations
: If 1t sent out distress signals, and its
that SOFA. passing vessel would pick up
the signal
Cites Tahiti Example.
An. example s.ted by Capt. Hooper
was in the case of the British steamship
Tahiti, which fcundered in the mid
Pacific on August II last Her. 251 sur
4Avors ~ere picked up by the Matson
liner Ventura after some ship or sta
ton. which. fortunately. was near
enough 10 scar the distrsss call' re-
laVe6 the message he said
Full detaiB of the radio contacts of
the vessel during the emergency are not
yet known Capt. Hooper explained, but
the occurrence brings to light again the
possible Danger which may Turk in the
existing lack 81 constant radio coverage
for every h,dy of water on the globe.
He said the matter WAS discussed in
preliminary way at tEe Washington
sRadiotelegraph Conference in 1927 and
r<obably again will be considered at
the forthcoming conference in Madrid
Short waves 'hav the propensity of
covering greater geographical areas
thar long or intermediate waves. de-
clared Capt. Hooper. The higher the
was pointed out.
In Capt. Hooper's opinion. the 500
kilocycle channel. which. under inter-
national agreement, is guarded con-
SStantly by'msSor stations of every coun-
try. ashore and af1oat, is not ideally
adapted as. the. international o S fire.
quency for ships at great distance in
from 100 to 500 miles during the gay
while at night it has, spread of pos
siblS 1000 miles, he said.
Combination System 3'ried Out.
Discussing the use Of high frequen-
cies, Capt. Hooper asserted that the
Navy for the past two months has ex-
perimented on Combination" system
of the use of frequencies at certain in
tervals, based on the geographical sepa-
ration between the ship and shore The
system has worked with success, he
said.
Because of varying conditions gov
erning radio, he declared, channel in
each of the various high frequency
bands was designated and transmitted
over at specified intervals. BY follow
ing the formula, both at the transmit
ting and receiving ends, the contacts
were maintained without difficulty.
Through such system a single oper-
ator could guard an international dis
tress band in the high frequencies,
whereas in the past one of the prob
lens has been that of devising method
whereby the services of only one oper-
ator for the East Coast would be en-
tailed in guarding the several frequen-
cies which would have to be employed
If the entire geographical range was to
be covered. international adoption of
such a process would require the con-
slant employment of several operators
for watch" duty, with prohibitive ex-
pense, he explained.
Indispensable Areas Cited.
In the Pacific, the South Atlantic and
possibly the Indian Ocean are areas
which are nH greatly frequented by
vessels and in which the 500-kilocycle
o channel is not entirely depend
able according to Capt: Hooper
Developments in the radio art, par
ticularly with respect to equipment
have been such as to make more feast
BILE the adoption of supplemental dis
trsss frequency in the short waves, ac-
cording to Capt Hooper. More and
more vessels are installing high fire.
quency apparatus and the economic as
poets Of the problem will largely solve
themselves, he declared.