11
4)(
TTTE SUNDAY OTIEGOXIAX. PORTLAND. OCTOBER 1. 1922
mm mi
Br SAUL EMANUEL.
THAT "radio". is becoming: a per
manent fixture of the Amer
ican newspaper has been proved
by the fact that many of them are
discarding their low-power "home
made" stations and replacing them
with highly efficient and powerful
apparatus.
There is a strong probability that
this improved service will soon be
part of the American social life in
all parts of the country. Already
several newspaper Btations in the
middle west are reaching: homes
v khin a radius of 1000 miles with a
widely varied daily programme.
There Is a radical difference in
the service given by the latest high
power stations and that of the ol'ler
and smaller ones. One thing is that
with a strong impulse to start with,
the receiving set need not include
many amplifier unitB and aquawky
horns to get a good reception. A
single tube with perhaps one stage
of amplification and- a wooden
sound chamber will bring in the
RADIO POWER TRANSMISSION
EXPERIMENTS ARE COSTLY
Inventor of Alternating Current Motor Spends Years and Fortune in
Research and Then Drops Broken in Spirit,
a v ADIO transmission of power has
l-c been a matter of discussion
w among our loremost eiecirica-i
engineers for many years. During
the early days of wireless telegraphy
several scientists experimental along
such lines but were forced to aban
don their attempts. Nickola Tesla.
Inventor of the alternating current
motor, spent several years and a
fortune on this phase of the wire
lets science and then dropped out of
the ranks, nearly broken in spirit
and mind.
The recent successful develop
ments in radio telephony brings the
question of the possibility of radio
power transmission agaro to the
e t u .-, .-1. .inn. hv lMaiioni
and others in the directing of radio
waves has given scientists a fresh
outlook on the subject.
"In some respects, radio trans
mission of power exists today, for
the message you receive by radio
has been carried by the power of
the electro-magnetic wave from the
sending to the receiving station,"
Dr. Charles P. Steinmetjs, one of the
greatest electrical authorities in the
WVriU, 1 1 1 I H I I LI in , irn lil oh v. u
to the radio congress at Chicago.
Dr. Steinmetz' address in abstract
follows:
While the sending station sends
out the electro-magnetic waves of
power of several kilowatts or even
.hundreds of kilowatts, this power
scatters In all directions and it may
be only a fraction of a milliwatt
which we receive, that Is. less than
a millionth of the power sent out.
But this small power is sufficient,
v.hen amplified, to give us the mes
SRtce. "The problem of power transmis
sion essentially differs from that of
tl:e transmission for communication,
tnat. in power transmission most,
it at least a large part of the power
sent out by the generating station,
must arrive at the receiving station,
to make it economical to transmit
the power.
"Hence. the problem of radio
transmission is that of directing the
radio waves so closely that a large
pirt of their power remains together
so as to be picked up by the receiv
ing station. Much successful work
has been done in directing radio
waves, and for instance our trans
Allantic stations send out most of
their power eastwards. But still,
even as directed, the power scatters
over the coasts of Europe from Nor
way to Spain, so that it is impossible
. to pick up any appreciable part of
It. The limits of impossibility of
concentrating a beam of radio waves
may be illustrated by comparison
w.th a beam of light. Light is an
electro-magnetic wave, differing
from the radio wave merely by hav
ing a wave length many million
Mmfta ihnrtsr Wh!U iisnnlli. Hvht
scatters , in all directions, like the
wireless wave, we can direct it in a
concentrated beam by the search
light. "But there is Inevitably a scat
tering of light In the searchlight
beam, and when the beam starts
perhaps with a square yard section
at the searchlight mirror, at 10 miles
distance It has at the very best
scattered to a diameter of 2000 feet,
and at 100 miles distance the beams
rover a section of 16 square miles.
If it were a beam of radio power.
It would thus require at 100 miles
distance a receiving station covering
16 square miles about four miles
wide and. what la still more diffi
cult, four miles high, to pick up a
larar nar. of the power. The cause
of this scattering Is two-fold. First,
the inevitable Imperfections of any
apparatus. No matter how perfect
a reflector, there are slight Imper
fections and at 100 miles distance
they seriously count. Furthermore,
even with an absolutely perfect re
flector, the beam of light would stay
together only if the light oame from
a mathematical point. As it must,
howtfver, come from a small area.
tKis causes an Inevitable scattering,
wnlch at best gives an angle of
scattering of about two degrees.
This is about 100 times as much as
w uld be permissible to economically
transmit power 100 miles by a di
rect radio beam.
"Theoretically, this is an Inter
cstirg speculation, but whether it
cculd ever become a possibility,
would depend on the question,
whether a radio wave of such length
could be found .as to make the losses
tf owe r by absorption, etc., eco
nomically permissible, and whether
Ktations for such wave length and
power would be economically fea
sitle. Furthermore, It would have
tc be an international development.
Therefore, even if such radio trans
mission by a stationary electro
magnetic wave sheet was possible.
Its realisation at best Is rather dis
tant, so that the present outlook
for radif power transmission is very
it-muic i iiiuuKiii u 1,1 interest now-
ever to bring this before you as an
interesting speculation of future
possibilities."
x
Nearby metal roots, eave spouts,
fir escapes and other masse of
music from a properly installed
500-watt station with perfect mod-
ulatlon and clearness. I
In most of the smaller stations
operating at present, but little at
tention haa been paid to the ac
coustic properties of the music room
from which the entertainment is
sent to the apparatus. Horns and
other devices allow a fair trans
mission of the entertainment, but
recent improvements have made
possible radio stations that send
out music and addresses with per
fect clearness.
With the type' of broadcasting
station recently built by the West
ern Electric company and Installed
by the Detroit News, the Atlanta
News, St. Louis Post-Dispatch and
other newspapers, 'a "studio" in
which all reverberating sounds or
echos are entirely eliminated, is an
important feature. The apparatus
Is In a different room. Special
microphones, the most Important
factor in the set. lead from the
"studio" to the apparatus and send
out into the air a perfect transmis
sion of the music or voice.
A considerable range is being
reached by these stations. A con
cert broadcast from the St. Louis
Post-Dispatch station recently was
heard distinctly in 47 states. A
score of fans near the vicinity of
Portland enjoyed many of the num
bers from the distant station.
The government recently issued a
new class of license, in which per
mission is given to high-power sta
tions broadcasting a highly effi
cient service to the public to work
on a wave length of 400 meters
This will allow the big stations to
work without . any interference
from the smaller one sending on 360
meters. The radio fan will be able
to pick his station as he desires in
the future.
metal may be absorbing some of the
radio wave that otherwise would
increase the current flowing in the
antenna and the sound vibrating in
the phones. Get the antenna away
from them as far as possible. To
let a radio wave pass a good elec
trical coductor on its way to your
antenna is like sending a boy to
Sunday school past a baseball dia
mond. It may get there, but the
chances are against It.
Changing the direction of the an
tenna may Increase the sound at the
receiver. If it is built like a "T,"
the ends should point toward the
stations that the operator most
wants to hear. If it is like an In
verted "L." the elbow where the
flat-top and the lead-in wire join
should point toward the sending
station for the loudest results.
There seems to be a funny bone in
such a joint as sensitive as the one
In the operator's elbow. A tickle
there gets more action than a slap
on the free end.
Golden Rule Commended
to R&dio Patrons.
Co-nperatloa iVeeeniiary for De
velopment of Great Indawtry.
EVERT industry that grows to
large proportions soon or late
develops controversies between
those engaged In it. Keen business
men naturally fence for advan
tageous positions, and friction and
hard feeling are the result. This is
especially true in radio broadcast
ing, where the present limitation in
the number of available wave
lengths makes for Interference, and
Interference In radio transmission
is not only irritating, but is harm
ful to the growtn of the industry.
First impressions go a. long way
with most people, and one who has
heard broadcasting where there was
"radio hash" is not liable to become
a purchaser of radio equipment at
an early date or to become an en
thusiast in the art.
As an industry grows older, .espe
cially if it grows to the magnitude
of the radio industry, the causes of
discord are thrashed out' and regu
latory measures bring about order
and a system of operation more or
less satisfactory to all. To get the
best results, however, something
more than regulation is necessary,
and that is co-operation.
The wise one realizes that he is
but a unit. In a huge community of
Interests and that what Is for the
good of the industry as a whole is
for his individual benefit, and be
readily agrees not only to conform
to the formal rules and regulations,
but voluntarily extends courtesies.
A code of ethics Is automatically
brought into being and becomes of
general usage.
The time will come, probably in
the near future, when, through im
proved apparatus and improved
methods, th available wave lengths
will be greatly Increased in number.
In the meantime radio enthusiasts
and those in radio for profit would
do well to apply the golden rule to
their methods. Otherwise radio de
velopment will receive a setback. -
Simple Condensers Very
Easy to Make.
Tw Conductors Separated by
Dielectric Suffice.
HOW often you've wished for
some simple makeshift vari
able condenser to experiment with.
What could be easier to make?
Almost any two conductors sepa
rated by a dielectric so that more
or less surface may be brought into
relation to form capacity will do
the trick.
Such common things as tin
cans may be utilized the insulation
being provided by using paper, or
even a coat of shellac or asp hal turn.
A can painted in this manner and
suspended so that its heishth in a
Ji.r of salt water can be altered will
make a fair variable.
Connections are made to the can
and to a plate inserted In the solu
tion. However, every part of the
exposed surface of the can must be
covered by the insulation varnish.
otherwise the condenser will be
short-circuited.
Two tin cans having: diameters so
that one just slides inside of the
other after a layer of shellacked
paper has been placed on the inner
can will give you a satisfactory
w ork.
Other arrangements will doubt
less suggest themselves to the
reader and if carried out carefully
will serve very well. When using
a variable condenser in series with
the aerial, the capacity should be
comparatively large. This can be
best obtained by using a fixed and
& variable capacity in parallel.
RADIO FAN AT OAK GROVE
INSTALLS NEW APPARATUS
Ben F. Lills Able to Use Handsome Phonographic Cabinet Either
for Playing Records or Picking Up Tunes.
frT"V
' i Av
r . If
;. ' ? ... ,JJV , ft
t'snRDfll reeelvlna: net owwed by Ben V. 1.1111a of Oak Grove, Or., which
can bwusfd either as phoaocrsph or radio by ftnaklnn; n slight change.
Concerts from all o-er the Pacific eoast are heard with thia set.
BEX F. L1LLIS of Oak Grove, Or.,
is an enthusiastic radio fan of
several months. And no won
der., with a receiving set like his.
who wouldn't be an ardent devotee
of the radio art, after he'had listened
to a perfect reproduction of a con
cert broadcast from a station way
down In California?
Mr. Lillis' set is unusual In several
ways. In a handsome phonographic
cabinet has been assembled three
stages of audio and one of radio fre-
quency amplifiers with all the va
rious tuning and battery units. Only
three controls are necessary to ad
just the receiver to its best opera
tion. One cdntrol does the tuning.
The other two take care of the radio
frequency potentiometer and tube
filament current, respectively.
Another particular feature of the
set is the arrangement whereby
either the phonograph or the radio
RADIO QUERIES
Editor Radio Waves and Ripples: 1.
Do you think it very good for & "peanut"
tube set that has received music from
Salt Lake City, Great Falls, Mont., and
Los Altos. Cal. ?
a. What is the highest voltage which
can be used as a n battery?
3. Whfrs is the bent place to put a
potentiometer and a voltmeter, and are
they necewwry to be used on account of
the filaments in the bulb?
R. F. Q Portland, Or.
. 1. v Yes.
2. Would not advise the use of
more than 224 volts for a detector
tube and 4jj volts for an amplifier.
3. A potentiometer is placed
across the filament battery circuit
with the pointer connected to the
grid circuit through the secondary
of the vario-coupler. A voltmeter is
also placed across the battery cir
cuit. Both of these units are not
necessary but if used will give you
a finer adjustment of the filament
current and will protect your tube
from crowding too much battery
voltage.
Editor Radio Waves and Ripples: Can
you sive me any information whereby we
can locate the source of telephone con
versations which we heard through a
mall radio set at our home ? As we
have not heard of a radio picking up
telephone calls we would tike to know if
this is a common occurrence or It, it a
freak condition? We have been heaiJnc
these phone conversations for several
nights. B. M., lorn. Or.
Picking up telephone conversation
on a radio set is not unusual. Such
cases have often been reported by
experimenters. It is usually due
to the antenna or lead-in wires
being in close proximity and run
ning parallel to the phone wires.
The fluctuating currents set up by
the speech traveling through the
wire induces a current In the radio
antenna which is reproduced in your
telephone receivers.
Editor Radio Waves and Ripples:
Please tell me through your columns what
sending elation. thoTe are in the vicinity
of Glendive. Mont., and how expensive
an equipment would be necessary to
hear them from near Glendive?
v AN AMATEUR. Portland. Or.
The only stations near Glendive,
Mont, ara KDYS at Great Falls,
Mont, and WD AY at Fargo, N. D.
It will be very difficult to say what
equipment is necessary to pick up
these stations from Glendive as re
ception will depend on many things
such as atmospheric conditions,
typography of the country, ground
conditions, etc. Would suggest,
however, the use of the standard
type receiver with two stages of
audio amplification which will cost
in the neighborhood of 1150.
Editor Radio Waves and Ripples: 1.
If a No. IS enameled wire is used for a
primary of a loose coupler would it be
proper to use a No 21 for the secondary?
If k, what sixe tubes should I use?
2. I have a crystal set and would like
to know if it is feaaible to use a loud ;
speaker. Up to a distance of 12 feet I
can .hear music plainly, but beyond that
I can only .hear faintly from the re
ceivers. G. Portland, Or.
1. A No. 20 wire should be used
for the secondary where the primary '
20-
can be used as desired. The change
from one to the other is simple and
can be done in a minute's time. For
radio work, a special "loud-speak
Ing" Western Electric phone is at
tached in place of the regular phon
ographic diaphragm. When there 13
nothing in the "air," and someone
wants to play a record or two,
the phone- is 'taken off and. the
diaphragm is returned to its "usual
place.
With this set the Lillis family
gets a good deal of music one way
or the other. Nearly all the Pacific
coast stations' are heard clearly and
Vith perfect modulation. Concerts
from The Oregonian tower and other
Portland stations roll in with con
siderable volume-; declared the Oak
Grove fan.
The receiving set was installed for
Mr. Lillis by a Portland radio con
cern, which is making a speciality
of assembling such apparatus in
cabinets of that kind.
AND ANSWERS
is of No. 18, because the larger wire
will afford much sharper timing.
Best results can be obtained with a
four-inch tube as the primary and
a 3 Vx -inch tube for the secondary.
2. A loud speaker is hardly feas
ible with a crystal detector as the
signals received have not power
enough to operate the loud speaker.
If you connect two stages of ampli
fication to th detector, you will be
able to get good results with a loud
speaker.
Editor Radio Waves and Ripples. 1.
Will a home-made grrid leak made of a
lead of a pencil mounted between two
brass screws serve the purpose as well
as the kind you buy in the stores?
2. Are dry celis a food substitute for
a storage battery m lighting the fila
ments of a vacuum tube?
3. I am using a detector tube In place
of an amplifier tube, but am having con
siderable .trouble. When in operation th
tubes light -up with a blue glow. Does
this denote anything? R. &., Salem, Or.
1. No. Such a device will not
have enough resistance by far for
use as a grid leak. A pencil mark
on a piece of paper between two
binding posts will suffice as a grid
leak.
2. The use of dry cells would re
quire replacement so often that it
would prove much more costly in
the end than if you had purchased
a storage battery to start with,
3. The blue glow is a sure sign
that your tube is being pushed be
yond its capacity and the plate volt
age should be lowered immediately.
The detector tube will not stand as
much plate voltage as the amplifier
and therefore will not give as good
results.
Editor Radio Waves and Rippuies:
Could a small generator be used In
stead of a storage battery to light the
filaments of my three tubes? I have a
generator which I drive with a water
motor. It has an output of from six to
eight volta and gives a direct current.
S. K.. Portland. Or.
Even though the generator gives
you sufficient current to light the
filament of your three tubes, the
current would not be steady enough
because the speed of the water mo
tor fluctuates greatly with the
change in pressure of the water.
Using the generator, your tubes
misrht burn dim one moment and so
bright the next moment that they
would burn out. The storage bat
tery is the only practical source of
current to use on the tubes.
Editor Radio Waves and Ripples: 1.
... in nuo new irRuuauce wvtj con
That I am reading about?
-. 1 nave a vacuum tube detector set
What can I add to increase my rcrtvintT
range ? S. T., Walla Walla, Wash.
1. - The resonance wave coll is a
coil of wire which is resonant on j
the wave length you wish to receive. J
This coil therefore will tune to at
narrow band of frequencies. Such a
coil must be built very accurately
and with the use of a wave meter.
The wire is wound until the
resonant point of the coil is on the
proper wave length. The point of
the coil depends on the inductance
, of th wire and the method of wind
. Ing which controls the natural ca
j pacity of the coil itself.
z. x ov can aaa two smgn wi
radio frequency and your range will
be Increased considerably. Also if
two stages of audio are also added,
the signals will come in much
louder.
Editor Rmdio Waves and Ripples: 1.
I am uains a ground consisting of a pipe
6 i-i feet tons driven into tha ground. Is
this a good ground or can you suggest a
better one?-
2. I imfiini a two-slide tuner with a
crystal eet. Would a loose coupler give
me better results for receiving radio
music? K. V., Porand, Or.
1. Your ground is not a very
good one. Cannot see why you don't
use the nearest water pipe which is
the best ground that can be found
in the city. Solder a large a wire
as you can to the water pipe and
you will get much better results
than the pipe driven into the ground.
2. The use of a loose coupler will
allow you to tune muh sharper to
the incoming waves and therefore
increase the receiving abilities of
your set.
Wireless Waves Are in
Many Different Sizes.
Marconi Gets Impulse Kstlmated
at 03 Miles Long.
IN the family of wireless wave
there are many different sizes.
The most common of these are the
waves ranging from 100 meters to
10.000 meters. Those of the 93-mile
length, or of 130.000 meters, are
only conjectural.
Marconi recently reported having
received an Impulse from a radio
wave which he estimated to be
150.000 meters long. Outside of his
report, nothing is known of this
giant.
At the other extreme In the radio
brotherhood is the 12-inch wave, the
smallest scientists have so far been
able to measure.
Hanging down the line from these
midget radio waves come the heat,
light, violet-ray. X-ray and gamma
ray waves. They become so tiny
that scientists have had to devise
a special method of denoting their
measurements. Meters and fractions
of meter are too cumbersome, rio
the meter has been divided into ten
billion parts, each of which la
called an Ansstrom unit, after the
man who invented the system.
In Angstrom units, therefore, the
smallest radio wave of 12 inches,
or three-hundredths of a meter, is
300.000.000 units long. From this It
is easier to comprehend the size of
the smaller brothers.
Thus, scientists have measured
heat waves to range from 3,000.000
down to 7750 units. Light waves
measure between this and 3900
unlts Then come violet rays, down
to 600 units. And so on down to
the tiniest of all the gamma rayB,
measuring one-twentieth of an
Angstrom unit, or one ten-billionth
of a meter!
Two brothers In this marvelous
family of wireless -waves are miss
ing. Scientists are still searching
for them. The only Identification
they can give is their sizes.
One of these missing brothers
stands between the smallest radio
wave and the largest heat wave.
The other's place is between the
smallest violet-ray wave and the
largest X-ray wave. What they are.
or what functions they might hav
in the general scheme of things,
scientists have still t discover.
Radio Notes.
SHALL, we be able to see radio?
That is not impossible, accord
ing to Professor Dayton C Miller
of the Case School of Applied Sci
ences in Cleveland.
In fact says Miller, an instru
ment could easily be devised by
which the smallest and largest
waves may be caught and photo
graphed as they flash by at the
. rfte of 186.000 miles a second.
' Professor Miller has been work-
i ing on a machine which photo
graphs sound waves. It is called
an oscillograph. The sound sent
into an extremely sensitive receiver
is made to vibrate a needle of light
whose oscillations are photographed
as they form.
Along the same manner, it -is be
lieved, the radio waves may be con
verted into sound waves which in
turn can be photographed by his
oscillograph.
By means of a new radio receiv
ing instrument, distress calls from
ships at sea can be detected auto
matically. The new signal takes
the place of the famous CDQ and
SOS calls.
It consists of four dashes of one
second each, repeated three times
at regular intervals. When this
code is received by a vessel equipped
with automatic Instruments, the im
pulses pass through a tuning coll
and then to four vacuum tube am
plifiers, where they are enormously
magnified.
After amplification the dashes
pass through an electrically oper
ated mechanism with ratchet wheels
and lever arms. The latter termin
ate in dash pots for the purpose of
giving the correct intervals between
signals. The ratchet wheels com
prise the "selector" and operate
after the manner of .the striking
mechanism of clocks. An electric
bell in the circuit rings when the
distress signal Is properly sent and
received.
When the operator on a ship sup
plied with the device goes off duty
for the night, he switches off his
regular equipment and connects the
automatic receiving set with the
antenna.
The famous long-distance radio
station. Nauen, in Germany, is to
be altered so as to increase its
range and to meet the increasing
traffic in the United States and
Argentine Republic.
Twenty-five million marks addi
tional capital Is being raised by the
Trans-Radio company and a begin
ning has already been made with
the constructive work. The plans
include the erection of seven new
masts, each 689 feet high, and the
dismantling of four of the existing
masts.
'As the number of radio listeners
increases so does the chance of
profit for the dispenser of patent
devices to- improve radio reception.
By this time the radio public knows
much more about static and its in
terfering effects than it did In
April. And after having an inter
esting lecture or well-executed mu
sical selection spoiled by the
cracks and hisses of the atmosphere,
the radio enthusiast is psychologic
ally in the proper status for the
operations of the vendor of a static
eliminator. At the time of this
writing such a thing does not ex
ist nor is there any immediate prom
ise of such a device; there has not
yet been put forth anything of the
kind which is worth the trouble of
installation. The United States pat-1
ent office is full of descriptions of
hopes , and aspirations along this
line, but nape of the patented pro
jects does what the inventor hoped
it would do. So. unless you have
some money yoi -want to lose. It
will be wise not to invest it in some
cartridge-shaped affair (or any
other shape) which draws static
out of your receiving set and dis
poses of It in a way you can't tinder
stand. A British medical journal recently
published an article that has caused
much discussion, regarding the pos
sible aid that may be afforded by
radio to the deaf. It is generally
known that persons who are unable
to hear direct, ordinary conversa
tional tones, can carry -on telephonic
conversations with ease. This is
due to the fact that sound wave,
recreated in the telephone receiver,
and sent directly into the ear of the
deaf person, are much stronger than
the sound waves as originally cre
ated by vocal organs.
The possibility of giving mechan
ical aid to a deaf person depends
upon the physical conditions respon
sible for the deafness of the af
flicted person. When the auditory
nerve is paralysed, sound waves, no
matter how strong, strike upon the
ear drum without effect. The aud
itory nerve is the interpreter that
translates waves into sound for the
brain. - j
If the deafness Is due to trouble!
of a less! nature, stronger waves
may be effective, and it has been
found that in some cases, hitherto j
considered beyond help, radio waves i
have been helpful. A man of 50 !
who had been so deaf for years that
he could only hear shouted sounds,
by increasing the number of thermi
onic valves in the radio receiver,
was able to hear conversations in
Paris. By experimentation it was
found that five thermionic valves
produced the best results in his case.
- .
The' prospectus which has just
been issued of the Chicago, radio
show to be held at the Coliseum Oc
tober 14 to 21, inclusive, indicates
that the show will be one of the
biggest and most Important radio
exhibitions yet held in the United
States and, if the prospectus is a
criterion, one of class as well as im
portance. The selection of the Coliseum,
probably the biggest and best-known
exposition center, gives the show an
adequate setting and the prestige
of the very many successful trade
shows that have preceded It. It is
planned as a "get-together week"
for the manufacturer, offering him
an opportunity of meeting the job
her, the dealer and the general pub
lic, and plans to make it appealing
to each faction are being perfected.
The arrangements for the show
are the product of the study of prac
tically every other radio exposition
that has been staged in this country
during the past year and a half, as
Its projector, U. J. Herrmann, him
self a showman of -long experience,
has visited practically all of them
to learn what not to do.
An outstanding feature of thl
show Is that over 60 per cent of the
floor space has been devoted to aisle
space for the comfort of the crowds
that will come at a season when the
buying public will show keen In
terest in the developments of radio
during the summer months and at a
time when they are looking for some
diversion for the winter months. It
has been announced by the manage
ment that several foreign countries
have considerable exhibit space un
der option, which will assure an in
ternational Interest
The New General Electric
Tunner Detector Amplifier
A Complete Radio Receiving Station
This compact and highly efficient receiver is of the sin
gle circuit type with a continuously variable air conden
sor for tuning. Provided with a regenerative coil for
amplification and oscillation. Suitable for reception of
voice and all signals.
Come in Let Us Demonstrate
1TT3
Broadway
1696
Tf eiL Cl
E.LECTRIC CQ
SPECIAL WE WILL BROADCAST MONDA Y
ROSE'S FAMOUS ORCHESTRA BET. 6 AND 7P.T'
Going Out of Business?
J Should Say Not!
Merely overstocked in certain articles and must "clean
house" of odds and ends.
Our sale advertised in last Sunday's Oregonian will be
continued for another week with additions, a few of
which are listed below :
Price
Original. Sales.
Elite 43-plate Condensers $4.75 $1.5
Triple SoAets, Elite $3.30 $1.00
Fada Rheostats $1.00 .73
Arkay Phonograph Attachment .' $1.50 .80
Paragon Crystal Detectors $1.75 .00
Arkay Vernier Adjusters $1.00 JTM
Firco Bulldog Grip Plugs $2.50 91.00
Tuska Variocoupleis $8.00 f 1.40
Fada Detector and Two-Step Amplifier with
filament control jacks in oak cabinet $65.00 $35.75
The
J. B. WEED, Mgr.
(The Oldest Exclusive Radio Store in Portland)
Mail Order Service Write for Catalog
310 OAK STREET (Installers KGW) Portland, Oregon
COMBINATION CIRCUIT NOVEL
AND EFFICIENT IMPROVEMENT
One Stage of Radio Frequency Amplification and Crvntal Rectifier
Being Used in East With Excellent Rcnulta.
One ta:e ef radio freqaeary. ewMMnee. mith m rrytsl deteetAr, makes mm
efficient receiver for radlosbane. In anek-iip, V nrlmeer. 1 By
pa ron demur of .O02 mfd., I Potentiometer of UOO ohmm, .tstorase
battery, B Plate ballery, 1 R Bndln frewurncy transformer, I Crys
tal deteetor, t'Ifr Phone condenser, .OOl mfd.
A COMBINATION of one stage
of radio frequency amplifi
cation and a crystal detector
is being used by many eastern ex
perimenters with very good re
sults. Such a circuit is quite simple
and easy to operate.
It has been Mng known that as
a rectifier the cyrstil detector is
quite on a par with the vacuum
tube. It has advantages not enjoyed
by the vacuum tube. In that it Is
practically nolseloss lit action. Mu
sical reproduction in the telephone
receiver with a crystal detector is
usually sweet and clear.
In a radio frequency combination
with a crystal detector.' the crystal
should be of a more rugged type
than galena. Silicon or iron pyrites
are recommended, as these reduce
the necessity of frequent adjust
ments, i
Units necessary for such a set are
ai follows: One standard short--
vave variometer, one vacuum tube
of the amplifier type, a tube socket,
filament rheostat, one 200-ohm po
tentiometer, a fixed condenser of
.002 microfarads capacity, one 6-volt
storage battery, a "B" battery of 4b
volts, a radio-frequency transform
er, crystal detector and telephone
receivers. .
Connect up the units as in the
diagram.
A little attention must be given
to ret the correct setting of the
potentiometer. After this is done,
a slight adjustment of the vario
meter wilt tune the aerial circuit to
the different stations.
The tube will operate best when
lighted at a little more brilliancy
than is usual with the ordinary tube
set. The best results are obtained
with the potentiometer pointer al
INC Store
1 P
most completely over to the neg
ative side.
The crystal detector 1 operated
in the usual manner. It will be
found that not so much attention is
needed to find the most sensitive
spots.
.
Kxperlmenters who have used
uth a set dec is re that It t tines
quite sharply. Interference from
the spark stations Is rut down al
most to a minimum with a small
variation of the variometer.
The rnost powerful broadcasting
station in the United States will
soon be Instslld In Washington,
I. P., accord in!1 to an announcement
made recently by the Had to Cor
poration of America. The station
will be Iocs ted In a new build Ins;
now being erected In the highest
section of the city. The finet
"concert studio" ever bull for radio
broadcasting Is being planned. A
practically all -day st-rvlce will be
arranged by the company. leading
entertaipers, speakers and educators
of the country will feature the pro
Kramnion of this station, whi-b. are
expected to b heard In almost
everv nort Inn of t'e t'nttfn Htt.
Radioize Your
Phonograph
We will gladly convert your
phonograph into a
Combination Outfit
so you can enjoy concerts
Either Way
Hear the radio when it is
being broadcasted or hear
your own records whenever
you choose.
Radio Service
Bureau
Gasco Bldg. Main 4533
NOTICE
TO
EASTERN OREGOSI
Wo Inntallr tha
"POHD CARAVAN"
KAUIO.
WATCH FOR ITt
HALLOCK & WATSON RADIO
SERVICE
IM PAHK MTHKffr,
Port lm ad, OrrBoa.
Rroadfastlne; fitatlnn KOQ
Expertmtnlal tuition 7X1.
One-Stagre Radio
- Frequency
adds greater distance to your
set. Complete stock of
Transformers
Potentiometers
Vernier Rheostats, Etc
M. J. WALSH
ELECTRIC CO.
106 Fourth Street
BKT. WASHlNtiTO!" AND STARK
E. L. KNIGHT & CO.
449 Whliwtm .. r 12th
HroadsrST OM.
CALL 1 lor IIKWONTRATIO
NO OBI.K.A 1 11
Radio Krta aad I'arta
"DIBIT HUES OAT THE ELECTRIC WIT"
RADIO SETS
of all klnriH. rnxAt to yonr order.
Complete ta In Mtorlc
Uarga aupply of parta.
SMITH-McCOY ELECTRIC CO.
Zt Alder St. Mala ftOl I.
RADIO rlK AD THKORT
l I HI I IO
NORTH PACIFIC RADIO SCHOOL
Opening- about Oct. 5. Pnjr anil nlrht
clAHneN. Special attention to cctta
instruction for the radio fan.
Approved progressive method.
R. T. atyea C. I. fialreaa
ItUaesi 2XMI5 or Uallaek Wataaa