Evening star., 1928-02-14
|NTERPRETS RADIO
TERMS FOR PUBLIC
Or. DeIIinger Makes Technl'
cal Language Clear to
Average Person.

Like the comprador OF emma. VINO is
the economic Intermediary between Oc-
cidental sellers and oriental buyers. DR..
7 n Del;nger of the Bureau of Stand
ards is unouestionably one OF the out
standing interpreters Of radios techni-
calities. Just as the comprador reveals
70 the outsider the merchandising mys-
ter;es Of the Orient. so DR.. Dellinger can
make the intricacieS of the radio art
understandable 10 the layman.
This remarkable faculty has been re-
vealed by the chief of the Government
great radio laboratory at washington in
government publications. magazine arti-
cles. statements to the press and, more
recently. in his contributions to the
revised edition Of his handbook on
radio. The purpose Of the volume is
to cover every phase of radio science,
from its fundamental principles TO the
making Of receiving sets at home. in
language the average man can under
stand
Why use both kilocycles and meters
In measuring wave lengths? Dr.. Del
lnger asks. and recommends:
The frequency Of the electric current
In radio transmitting or receiving an
terna is designated in kilocycles per
second A kilocycle is 1000 cycles or
complete alternations Of the direction of
the current. The freQuencies used in
radio tranniSsion range from IL to
10000 kilocycles.
The wave length is the distance
from one wave crest COR nlaXinuml to
the next Radio wave lengths range
from $4,000 to Is meters. The meter
Is 29.S7 inches (about $685. inches) and
IS the unit of length used all over the
world except in the United States and
British Empire
Wave length has nothing directly to
do with the distance 10 which a radio
wave travels. Similarly. a sound wave
or water wave may have wave length
OF one foot. but such wave could
travel very many feet. 1t is urged
that every one familiarize himself with
and think In terms Of kilocycles as soon
as possible. inasu7uct as waves are now
assigned in even values in kilocycles
II is expected that the use Of the term
wave length in radio will gradually dis
appear"
Much is being said about heterodyn-
ing. What does the term mean?
"HeterocyDlng, as applied TO broad
casting signifies the interference be-
tween the waves OF two or more stations
operating on nearly the same frequency.
The whistle heard in a receiving set
tuned TO one Of these stations is often
called the 'heterodyne whistle The
frequency OF the note heard depends
upon the difference between the inter-
fering frecuencies. Thus. If a station
operating on 500 kilocycleS interferes
with the program OF another station on
4o9 kilocycles, a 'heteredyne whistle of
1000 cycles will be heard in the receiv-
Ing set. As long as the two stations
operate within 10 kilocycles of one an
other, there is likelihood Of receiving
the heterodyne whistle or al least of re-
ceiving distorted program.
This principle may be clearly illus
Cated oy plucaing two strings of a
Violin which have nearly the same note.
slow beat note will be heard. The
frequency Of this note may be varied
by changing the pitch Of one or both
o. the strings. AS the difference be-
tween The two notes increases. the beat
frequency increases until il becomes too
nigh 10 be audible The two strings
represent the broadcasting stations OPP
Grating on nearly the. same frequency
and the beat ncte is the 'hetcrodyue
whistle"
William Green. president Of the
American Federation of Labor. and
Senator La Toilette of Wisconsin will
face the microphone of WRC tonight in
the Voters Service" program which
viii be broadcast from to 7:30 O'Clock.
under the auspices Of the National
League Of Woman Voters. What
labor May Expect From the Political
Parties in 1923" is the subject Of Mr..
Green's address. Senator La Follette's
topic has not been announced
Comdr. Herbert Hartley, for five
years master OF the S. S. Levia,han and
commodore CT the United States Lines.
also viii broadcast tonight through
American ships His speech will 90 on
the air at 7:30 O'Clock
WRC's musica! attractions will be
provided by the Seiberiing Singers ano
the Sealy Air Weavers. Pan-American
selections viii be featured by the
Seioerling group. Cotton" and
Morpheus. who will be heard during
the Air Weavers program. have planned
To initiate Laundry wagon drivers.
Joseph Parson, baritone. who sang
IL the revival OF Robin Hood; Wesley
EDDY. Lee Cronican and a group Of
otne. artists will take part in the
weekly radio movie club. the chief at
~ o~%SIA bjA1bAA "a "AlAL. n supper
caoce program BY the Silver String
Ee9eie.s and z vocal selection By JACK
Harris ard Fred Bolts Gre among the
other musical features
This station also has scheduled two
talks, one by Louis Rotktchild. director
G! WaSaington's Better Business
Bureau. and THE other by B. Car
michael Q! .he University Of Maryland.
Ihe evening program of WRHF in
c!Oces the second Of a series Of personal
cfaN by Edwin Cailow, otherwise
known as Tony the Barber. and
dance program by George EkAdcing and
his ConsreSsionala. Caliow Will broad
cast from 6f5 10 7 O'Clock