Evening star., 1931-04-05
Behind the Microphone
BY THE RADIO EDITOR.

wave length without interference
and regardless of their respective
powers.
After three weeks Of synchro-
nized operation of VITO, Hart
ford, on the wave length Of WEAF,
New York, and of WBAL, Balti-
more, on the wave length Of WIZ,
New York, engineers and repre-
sentatives of the stations report
that they are well pleased with
the results.
Field test and listener reports,
in general, reveal that the stations
are covering their normal service
areas well; that Is, the reliable
range around their tranSmitters
that can be expected from their
powers. The "mushing" and dis
tortion that occur are reported
from points distant from the sta
tions, some Of which points for
merly enjoyed service relatively
free from interference.
1--WE haven't mastered the
problem entirely" says c. w. Horn,
N. B. C. general engineer, directing
this development. But we know
now we are on the right track.
We just haven't reached the ter
minal as yet"
Horn says that the actual syn
chroniZing Of the stations pro-
grams has been accomplished by
means of the new StAbilizer device
which, via land lines, keeps each
stations operations in precise
phase with the others. There
Is no trouble about off-frequency
operation. The difficulties that
are being experienced, he says,
grow largely out of sky-wave in
reference; that is, the interference
that Is caused by the return to
earth of the radio signals after
they have been reflected from the
radio ceiling" known as the
HeaviSide-Kennelly layer.
Unusual atmospheric conditions
In the East in recent weeks have
placed an extra heavy burden
upon the experimenterS, accord
ing to Horn. The highly complex
| technical nature of the expert
ment is requiring intensive study
of the finest points Of radio, espe-
cially of wave propagation.
1--WE have definitely demon
strated," Horn said, that we can
cover the immediate service areas
of the synchroniZed stations with
out interference. Listeners in New
York, Hartford and Baltimore
have made no complaints; in fact,
they don't seem to have noticed
any difference, except that in
Hartford and Baltimore the lis
teners are enabled to hear their
stations full time where they for
merly heard them only half time.
Outside of the cities, however,
there has been some adverse re-
action. We have our monitoring
men stationed at various strategic
points to study reception condi-
tionS under the unusually erratic
atmospheric conditions that now
prevail. Patience and hard work
will unqueStionably conquer the
problem in the end"
Horn points out that no one
least of all the listeners, are losers
by the SynchroniZing experiments
for the reason that, sharing the
same clear channel, VITO for
merly had to remain silent while
WBAL was on the air, and vice
versa. Now each has full time
albeit each has to use two sets OF
wave lengths.
Station VITO synchronizes with
WEAF Mondays, Wednesdays and
Fridays until pm; on Tuesdays
Thursdays and Saturdays after
pm, and on Sundays until 7:3o
pm. Station WBAL synchronizes
with WIZ on Mondays, Wednes-
days and Fridays after 4 pm; on
Tuesdays, Thursdays and Sat-
urdayS until 4 pm, and on Sun
days after 1880 pm. At other
times each operates on their usual
joint channel Of 1000 kilocycles.
/