Evening star., 1935-07-07
Trans-Sea BrOadcasts
Full of Technical Skill
Science of Land, Ocean and Air Is Required
to Bring Audible Waves to
y. S. Listeners.
By The Radio Editor.

"HERES lot of ocean to cross
and often lot Of land as well
when Columbia brings its lis
Il teners fanciful programs from
romantic, far-away places. In addi-
ton, there are some curious tricks OF
nature to overcome in staging trans
oceanic broadcast, whether it be a
talk by George Bernard Shaw from
London or q pickup Of typical native
activities in an Egyptian village street.
One of the considerations necessary
relates to the differences in time be-
tween America and the foreign point.
The time of the broadcast must be
adjusted to the advantage of each
country and sometimes the difference
in time is so great that the available
program period is narrowed down to
O very short time of the day
Even stranger, perhaps. and not
generally realized, is the effect of the
broadcasting. The choice of the proper
radio frequency varies with the posi-
ton of the sun and the distance to be
spanned. Frequencies, in simple terms,
are transmission measurements of dis
tance, provided the time of day. mag
netic conditions. height of ironized re-
Election layer, which varies between
80 and $50 miles above the earth, and
the actual distance itself have been
carefully considered. The transmits
sion distance varies with the time of
day or with magnetic conditions and
makes it necessary to employ different
frequencies throughout various periods
Of the day and night.
WHEN magnetic conditions are nor
NAL. the preferable time for short
wave broadcasting is when both coun-
try Of origination and the country of
reception and the distance between
are in either total sunlight or dark
ness. The sundown period at the
point OF reception, with a correspond
ing darkness at the point of transmits
sion, may cause confusion or fading
Of the signal with consequential poor
reception as possibility. The prefer
able period for broadcasting from Eu-
rope is in the morning or early after
noon, mainly because of both coun-
tries being in daylight.
Magnetic conditions change the nor
NAL consideration of what frequency
to employ and engineers must there
fore be something of mariners in the
selection of the current frequency.
They must consider the time of day in
each location and the distance to be
spanned; they must study and chart
magnetic conditions and storms and
find common meeting place" in the
ether before reaching out over the sea.
COLUMBIA'S transoceanic broad
casts originate between the public
events and special features department
Of C. B. S. in New York, headed by
Paul White and the European director
tor c. B. S., Cesar Saerchinger, who is
likely to be anywhere at any time.
The broadcast is developed either
from quietly planned porgram pre-
senting something of entertaining
travel interest, such as the recent
pickup from the land of the midnight
sun in Norway and Scandinavia, or
from q spontaneous development of
news Importance. This latter may be
anything from a talk by the Pope to
national revolution or a major dis
aster.
The program Is short-waved to
America in either of two ways. 1t
may be fed by land telephone lines
to London from any part of Europe
and thence short-waved to receiving
point in New Jersey. From there it
is spread over the network through the
main master control room in New
York. The other way involves short
waving direct from a half-dozen ma
jor European points-Berlin, Paris,
Moscow, etc.-to Riverhead, Long
Island. Riverhead likewise relays it to