Evening star., 1925-01-11

distances up to 400 miles to indicate
that all three radiating receivers
could be heard over that distance on
a. sensitive receiving set. Many per-
sons reported hearing only the first
two sets in Cleveland. That may be
because the Akron set was weaker
than these, or because 1t sounded diff
rerent and may not have been identi-
fed
AS to the intensity of the squeals
from these three sets-in the city of
Cleveland, over an area of some. so
square miles, where there are thou
sands of radio listeners, the two Cleve-
land sets were heard with great in
tensity. Certainly they were loud
enough to have interfered with re-
ception from distant points any place
In the city. The West Side set was
loud enough TO have interfered with
even local reception at distances as
great as 13 miles. Indeed, listeners on
the East Side of the city reported they
would have thought the West Side
"squealer' next door had they not
known the location.
The Akron sQuealer was heard only
family in Cleveland, and the Cleve-
land squealers only family in Akron.
In either case no serious interference
would have been experienced from them.
Although heard at great distances, the
sets probably would not have caused
what might be termed interference at
distances greater than 25 miles.
But consider how many receivers
capable of radiation there are In a
city like Cleveland, where almost any
one Of them may interfere with recep-
tion by other sets tuned to the same
wave all over the city
What shall be done about interfer-
ference from oscillating receivers, is
not known, but the above tests are
another addition to the accumulated
evidence which indicates that such
interference is the most serious prob
lem of radio reception today.
Amateur Regulations Nodded.
Amateur operators of radio trans.
mitting stations will be accorded d
slightly broader channels in the low
er wave lengths in 1925, although they
lose the band between los and 110 me-
ters under revised amateur regula-
tions just issued by the Department
OF Commerce. Radio phone, spark and
&c" transmitters may be used only
within the band from ITO to $50 me-
ters, but CIV transmission may be
carried on within the following wave
channels: 4.69 to 5.35, 1877 to PA, 81. 5
The department urges the aban-
donment of the spark transmitter as
soon as possible and the adoption of
sets causing less interference. No
new restrictions will be imposed rela-
tive TO the character of the power
supply, the department regulations
state, provided the emitted wave is
sharply defined and the power does
not exceed 500 watts, set by law.
Amateurs using the band between
$50 and 200 meters. which includes
all spark, phone and ICW transmit
ters,, are required TO remain silent
every night between and 1880
standard time and on Sundays during
using wave lengths below S5 meters
and having pure continuous wave,
or where full wave rectification is
employed are not required to remain
silent. except when interfering with
other radio services.
Special amateur licenses are abol-
ished, but owners of stations so
licensed may continue to use their
''Z2" calls under new regular amateur
licenses. No more special "Z' licenses
will be issued. as the department feels
there is no longer need for them
Amateur stations are not permitte ed
to communicate with commercial sta
tions unless so authorized or in
emergencies.
All supervisors of radio have been
directed to enforce the new regula-
| tions at once.