Evening star., 1924-12-26
RADIO QUERIES
Radio Editor:


house current not used in radic
work? There are step-down trans.
formers on the market which will de
crease the high voltage Of house cur.
rent to point where 1t can be uset
to operate bells and other electrical
appliances reQuireing low voltage
A NEW READER OF YOUR COLUMN
The reason Is that good reception |,
dependent on an even and quiet flow
of energy to the tube which is no
provided by s+ep-down transformers
Batteries on the other hand supply
exactly the kind of energy required
up to a certain point, then they mus
be discarded and replaced with new
ones. or If Of the wet-cell type must
be recharged.
Radio Editor:
In Radio Queries" December 20, z
B. Lane complains Of interference from
an amateur spark station which he
thought was in the vicinity of Chevy
Chase. He describes 1t as calling
ABA and wGH for lengthy inter
walls. / would like to advise him that
the station he heard was WGH. II
is located at Tuckerton, \. j., over
$50 miles from here, and is controlled
by the Radio Corporation OF America
which also controls WRC In this city
Its wave length is 100 meters,
which makes 1T absolutely impossible
for this station to interfere with re-
ception on the broadcast band, unless
the receiving set was oscillating. a
condition which Is not desir BILE
when receiving music or voice.
On December % c. D. Cook takes
particular pains to slam the amateur fol-
interference. He ridicules ship and Gov
eminent stations and asks why ships
cannot navigate without frequent COM
munication by radio. Any ship can steer
its course by compass and sextant with
out aid from radio. but the ships trans
nitter Is the only means Of con1munica-
ton with land and other ships. Pas
sengers dispatch radiograms for their
friends on shore in the same way an
ordinary telegram is sent over land. and
messages are often numerous enough to
keep the transmitter going several hours
at a time.
Mr. Cook says that drastic steps
should be taken to insure good recep-
ton "if radio broadcasting is to con-
tinue as a popular amusement" He GER
tainly described 1t we'll when he called
Il a popular amusement, yet he expects
that the Government will shut down its
own stations and those on board ships
to cater to amusement. Business must
always come before pleasure.
As far as interference from amateurs
Is concerned, there Is not a chance in
the world, unless you live right next
door to one or have set which tunes
to 200 and to sos meters at the same
time and few other odd waves
thrown in to insure maximum interfer-
ence at all times. 1t Is the owners OF
inefficient sets who make most OF the
howls, both In your column and on the
air.
No matter what wave length a
station is sending on II is quite easy
to hear 1t in one or more places with
in the broadcast band IL your re-
ceiver Is oscillating. MSS at Annapolis,
Md. can be heard on fully so diff
ferent waves inside the broadcast
band, yet MSS is on a wave length
of 1880 meters. Amateur stations
on waves far below 100 meters can
be heard equally we'll but If your
receiver is not oscillating you will
listen for them in vain. With three
tube receiver only four feet away
cannot hear my own transmitter on
any wave but the one to which il
is tuned, and you may be sure that
that is far below goo meters. The
reason why lies in the fact that a
receiver will respond
to only one wave, while an oscillat
ing receiver will respond not only
to the wave to which 1t is tuned but
to many others. Harmonics and
overtones Of the main wave can be
heard nearly as well as the mair
wave itself, and II is through then
that the interference is heard. Har'
monies occur at simple fractions and
overtones at multiples of the mair
wave The actual number of then
which can be heard depends upor
the strength and distance OF the in
terfering station.
If II Is possible to hear the car
rier wave Of a station on your set Il
Is capable Of oscillating and wher
II Is in this condition It Is very sensi'
to get q distant station, what Is tht
quality OF the music or speech? AL
kinds Of whistles are present anc
clear reception Is impossible.
But when your set Is not oscillat'
ing you will rarely hear such inter
ference, and the music will be o1
good quality. Remember your neigh.
Dor can hear your receiver, when II
is oscillating, on his set and he gets
interference from you. 1t pays tc
be courteous in the way you rur
your RECEIVING SCI dS ~Sii no you'
business.
II you do hear interference, frs,
be sure 1t Is not the fault OF your
own set, then be sure about the iden-
tity Of the interfering station before
you blame an innocent party, and
lastly, remember that broadcastine
is only one OF the many services
which use the air and all must have
equal rights.
I hope this will clear up some oil
the difficulties about interference
w. NJ. BROWNE, Station 3HQ.