Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-10-24
TWO SHORT-WAVE
PRINCIPLES. NEW
World Conference Proposals
to Be Made Known
Here Today.

Two principles of major consequence
in the use of short waves as a medium
Of communication we're adopted by the
radio engineering fraternity OF the world
at the technical conference held last
month at The Hague, Holland. They
will be made known today by the State
Department. as Maj. Gen. Charles NICK.
Saltzman, chairman of the delegation
sent to the parley by President Hoover.
returns to resume his duties on the
Federal Radio Commission.
One change in present engineering
practice recommended by the engineers
will have the effect of practically
doubling the number of channels avail
able In the high-frequency spectrum.
The other technical principle adopted
will open part of the wave band now
reserved for transoceanic communica-
tions to daylight use in communicating
over shorter distances.
Proposals Not Mandatory.
Although the delegates at The Hague
were offlcially designated by their gov
ernments, their proposals are not man
ratory. They concurred, however, in
recommending practices to be followed
by their respective radio administra-
lions until they can be made the sub
ject OF treaty obligations at the next
world radio conference, to be held in
Madrid in 1882, in conformity with the
provisions of the Washington Radio
Telegraph Convention of 1927.
Improvements in radio apparatus have
been such since the conference here,
only two years ago. that the technicians
agreed that a two-tenths Of per cent
separation between frequency
channels was too liberal, and that fire.
Quency tolerances. or the extent OF
"wobbles" permissible from any given
channel, should be reduced. Accord
ingly,. they agreed to cut the separation
to one-tenth of per cent, thus viz
tually doubling the number OF channels
that can be used.
AS soon as Is practicable all the users
of radio channels will adopt this mar
rover spacing, or sharper tuning"
The principle will be applied more rig
idly to fixed stations than to mobile,
such as those on ships and aircraft. for
the reason that the latter cannot be
controlled as readily.
U. s. Redistribution Likely.
In the United States the proposal
may mean the redistribution of short
wave assignments, because the space
now used by many stations is consid-
cred excessive for their radio-telegraph
emissions. Attention was concentrated
at The Hague parley chiefly on the short
er short waves, or those from 5000 to
$500 kilocycles $50 to Is meters. These
under the Washington regulations are
reserved for long distance communlca-
ton, chiefly tranSoceanic.
It was part of this band Of frequen-
cies that the experts agreed to make
available for domestic and short-dis-
lance communication during daylight
hours, when they will have no inter-
national interference effects. Specifl-
cally it was agreed to open the band
from 5000 to 5000 kilocycles $50 to 80
meters)s for use as each country sees Mt
during the period from two hours after
local sunrise to two hours before local
sunset.
The wave lengths in this band have
a range of approximately $50 to 1,100
miles, so that they now may be used
within the country, and will probably
be assigned for domestic radio-teleg-
raphy over short and medium distances
It may reasonably be expected that
there wiz be averitable scramble for
these channels, for nearly all OF the
other short-wave channels have already
been assigned by the Federal Radio
Commission
Other Problems Considered.
Many other technical problems were
considered at the conference and vari-
Gus other agreements were reached on
the technical "modus operandp' to be
followed pending the Madrid treaty.
American amateurs, who were repre-
sented on the United States delegation
by x. B.Warner, secretary of the Amer
lean Radio Relay League, successfully
avoided coming under the provisions OF
a universal amateur license system, pro-
posed by the Dutch. It was agreed that
this license should be made the subject
Vws. N1xy
(CopyriEhe, 1879, by North American News
E paper Alliance)