Evening star., 1925-09-06
RADIO GOSSIP AND NEWS

So successful has been the perform
| ance of the 13 United States Light
House Service radio fog signal sta
tions that Is more are now being con-
structed or equipped with this means
of aiding navigation, while approx
mately 20 others are proposed
Within a few months the service
will have IT radio tube beacons in
operation along the shores of this
country. The new points to be pro-
tected by automatic radio fog signals,
! which enable navigators to avoid
| coastal dangers and locate their po-
| sitions definitely, include seven sta
| tions on the Great Lakes, one at Port
! land, Me; two in the Gulf, five on the
! Pacific coast and one in Alaska. The
old spark transmitter on the Nam
| tucket Shoals Lightship will be re-
| placed with a tube transmiter and the
operating periods of several stations
! heightened. OF the IS radio fog sig
| nails in operation, two have tube sets.
The first was installed on the Am
brose Channel Lightship, WWAT,
which is also equipped for regular
radio communication when necessary;
the other Is the Lake Huron Light
ship The plan, for having auxiliary
radio apparatus for communicating
with vessels is, also carried out on
other lightships or will be soon.
The British liner Majestic always
uses the fog signals of Nantucket
Shoals Lightship regularly. This light
ship, known as WWA1,7 sends out
radio and submarine sound signals
simultaneously, which enable the nav
igators of vessels to determine their
distances from the lightship as well
as their directions from 1t by radio
compass. Although termed fog signals,
the emanationS from these beaconS, all
on 1000 meters, are frequently sent in
both good and bad weather. They
have distinctive forms and operate on
established schedules. WWAH at
Nantucket, for example, sends out
four dashes, repeating them for a
minute, following which the transmit
ter is silent for a half minute. The
blasts of the submarine sound signal
are a little different, but in each rep
etition of the characteristic signals
the first dash of the radio signal and
the first blast of the submarine sig
nal are sounded simultaneously. "a
The difference in time in seconds
between the reception on ship of the
radio dash and the sound blast null
tiplied by 1900 gives the distance in
yards the vessel is from the flagship.
The ships radio officer. who listens
in, is equipped with a special pair of
head phones, one ear piece of which
is connected with the radio receiver,
the other to the sound receiver, so
that he can count the seconds between
the receipt of the two distinctive sig
nails. AS the sound signal travels less
rapidly than the radio signal, there
is always a lag of several seconds, de-
pendent upon the distance; each sec
ond indicates distance OF 1900
yards.
The new tube transmitters, rated
at 500 watts, like many four broad
casting stations, have two 250-watt
power tubes. Every part of the radio
equipment is duplicated. The wave
length of the beacon service is 1000
meters. When these sets are Installed
on nghtships or in lighthouses where
regular radio communication is be-
lieved desirable, one of the transmit
ters is equipped with wave chang
ing switch, permitting operation on
900 meters, the marine calling and
distress wave length, and also on 73l
meters. There are in operation today
80 vessels of the service equipped for
radio communication, of course carry
ing radio operators. This number in
cludes &c light vessels, the balance be-
ing sea-going tenders and relief light
ships. Many of the masters on the
lightships and in shore lighthouses
have built or purchased radio receiv-
ing sets on which they listen in reg
ularly, chiefly for recreation, as regu-
lar Government and commercial radio
stations along the coasts listen in for
distress calls from ships at sea. The
receiving equipment has proven val
liable in some emergencies, however,
and tho ,ISa of these sets is encOur-
aged.
The Great Lakes stations under con-
struction are Devils Island, Manitou