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Enter
The Fascinating World
of Vintage Communications
Spring, 2016
Marconi
transmitter complex
Poldhu, Cornwall, England
Enter
The Fascinating World
of Vintage Communications
2
The Awa
The AWA Gateway is an electronic publication of the Antique Wireless Association, downloadable without charge from the AWA website, www.antiquewireless.org. Its purpose is to stimulate interest in vintage communications history, equip-ment, restoration, and collecting. OFFICERS
Director……………….Thomas W. Peterson, Jr. Deputy Director…..Robert Hobday Curator………………..Bruce Roloson Secretary…………….William Hopkins Treasurer…………….Stan Avery
TRUSTEES
Stanley Avery, WM3D James Kreuzer, N2GHD David Bart, KB9YPD Richard Neidich Lynn Bisha, W2BSN Thomas Peterson, Jr. Geoffrey Bourne Ronald Roach, W2FUI Marc Ellis, N9EWJ Bruce Roloson, W2BDR Robert Hobday, N2EVG John Terrey, W5TDQ Prof. William Hopkins, AA2YV Morgan Wesson David Kaiser Roy Wildermuth, W2IT Felicia Kreuzer, KA2GXL
MEMBERSHIP SERVICES COMMITTEE
Chairman .......................... Richard Neidich AWA Journal Editor .......... Marc Ellis, N9EWJ Membership Data ............ Ed Gable, K2MP* AWA Review Editor .......... Eric Wenaas* Conference Chairman ...... Roy Wildermuth, W2IT AWA Gateway Editor ....... Mike Rosenhouse, K2CDX* * Ex officio members
VISIT US ON THE WEB www.antiquewireless.org AWA GATEWAY Editor ................................ Mike Rosenhouse, K2CDX COVER ART (by Will Thomson): Transatlantic electronic wireless communication began on Decem-ber 12, 1901, when three “dits” — “s” in Morse Code — were trans-mitted from the complex pictured on the cover to Guglielmo Marconi, at his St. John’s, Newfoundland, receiving station (pictured here). The towers shown on the cover were successors to the antenna masts used on that historic occa-sion (photo courtesy David Read). The Antique Wireless Association, is nonprofit historical society founded in 1952.
Copyright 2016 Antique Wireless Association
P.O. Box 421 Bloomfield, NY 14469
Hi Everyone. It is a time to express deep gratitude and to tell you about some recent changes. Marc Ellis, who founded the AWA Gateway and has done an excellent job editing it for many years, wants to focus his full attention on the AWA Journal. We are extremely grateful to Marc for the great job he has done over a long period of time with the Gateway. At the same time, I am pleased to welcome our new Editor of the Gateway, Mike Rosenhouse. Mike is an extra-class ham (K2CDX) with significant professional editorial and writing experience. A graduate of University of Chicago Law School, he is a practicing lawyer, and the author of two law books and numerous published law-related articles. Over the years, he has also worked for Newsweek , the Chicago Sun-Times, The Wall Street Journal and the Yale Daily News. Mike was a history major at Yale, and his intellectual curiosity and non-technical perspective should be helpful in keeping the publication accessible to its intended audience. Mike says he can use all the help he can get. If you are inter-ested in being a Gateway contributor or columnist, please contact Mike at [email protected]. I know you all join me in wishing him the best of luck with the Gateway and in standing ready to offer any help that he may need.
* * * Do you buy items on Amazon.com? Well, who doesn’t? When you shop at AmazonSmile, Amazon donates 0.5% of the purchase price to Antique Wireless Association. Book-mark the link http://smile.amazon.com/ch/16-1501004 and support us every time you shop. It is really easy. Just sign in at the bookmark above or go to Smile.Amazon.com and des-ignate the Antique Wireless Association (EIN: 16-1501004) for the AWA to receive 0.5% of your eligible total purchases. You only have to designate the AWA once, but EVERY TIME you want to make an Amazon purchase, sign in using Smile.Amazon.com and you will be redirected to Ama-zon.com automatically. It is just that easy to support the AWA and it does not cost you anything extra. If you have not been to the AWA Museum recently, Phase II is nearing completion and the new exhibits are being in-stalled. Because the Museum is now over 7,000 square feet, we need people to volunteer as guides or docents on Satur-day afternoons from 1 pm to 5 pm. We provide the training and it is a great opportunity to learn more about the history of communications and meet some very interesting visitors to the Museum.
—Bob Hobday N2EVG Deputy Director, AWA Museum
F r o m t h e D e p u t y D i r e c t o r
AW A Gate wa y
3
From the Deputy Director by Bob Hobday 2
Better and Better: Broadcasting in the ‘20s
and ‘30s by Jim Cook
4
My Early Radio by Bill Phillips 8
Gravity Makes Waves by Prof. Alan Entenberg 11
Other Clubs 15
About AWA 17
Contents Spring 2016
Kilowatts for Freedom: Above are a Collins 821A-1 250,000 watt transmitter and control
room console from the Delano, California, VOA (Voice of America) Station, now on display
at the AWA Museum in Bloomfield, NY, courtesy of an alliance between the AWA and the
Collins Collectors Association to preserve and share the history of Collins Radio and Rock-
well Collins.
4
On this label on a 10-inch 78 RPM phonograph record from the 1920s that belonged to the author’s father, the term “electric”, at the top, was meant to convey “state of the art,” meaning that it was recorded with a microphone, audio amplifier, and electric stylus, allowing for better regulation of volume. On the left side are the words, “Radio Broadcast Not Licensed For”; early radio stations hired their own musicians to avoid such license restrictions. The recording is of “I Don’t Love Nobody,” by the Fiddling Doc Roberts Trio, on the Perfect label.
History in the First Person
AWA Gateway
Broadcasting in
the ‘20s and ‘30s
Better and
Better
The first radio broadcasters
were amateurs, i.e., “hams,”
and in the early days of com-
mercial broadcasting, radio
and recording were seen as
competing with each other.
Volume control was a big
problem.
By
Jim Cook, W0OXX
A lthough communications between radio-
telegraph stations had existed for more than 20 years
before broadcasting began, no one had any experi-
ence providing a radio broadcasting service that
would appeal to the general public. The earliest
broadcast stations, such as KDKA in Pittsburgh, Penn-
sylvania, began as amateur radio stations. They
brought news reports and sometimes set up a phono-
5
graph next to a microphone to
play music for their listeners. Lat-
er, they had studios for live perfor-
mances. But there were questions
about how to pay for this service
and what program material could
be used.
In the United Kingdom, broad-
casting would be owned and con-
trolled by the government. Listen-
ers had to pay a tax on each radio
they owned to cover the costs of
this broadcasting service. Alt-
hough this possibility was debated
in the United States, there was a
strong desire to keep American
broadcasting under the control of
private companies and to make
radio listening free to the public.
For this to be financially feasible,
advertising was allowed to cover
the costs of broadcasting.
The development of the phono-
graph also had an impact on the
radio broadcasting. Prior to the
1920s, all phonograph recordings
were made acoustically by having
the musicians perform in front of a
giant horn that collected the
sound and carried it to a mechani-
cal stylus that made the recording.
The only way to control the loud-
ness of the recording or the sound
levels of each musician was to re-
arrange them on the stage in front
of the horn. In retrospect, it is
amazing that some of the early
acoustic recordings sound as good
as they do.
Fortunately, the development of
vacuum tube amplifiers provided
an opportunity to make better re-
cordings. I have included an illus-
tration of the label on a 10-inch 78
RPM phonograph record from the
1920s that belonged to my father.
This recording is on the Perfect
label, and the selection is "I Don't
Love Nobody" by the Fiddling Doc
Roberts Trio. At the top of the la-
bel is the word "Electric" which
meant that this record was "state
of the art," recorded with a micro-
phone, audio amplifier, and elec-
tric stylus.
“Radio Broadcast Not Licensed
For”
On the side of the record label is
the statement, "Radio Broadcast
Not Licensed For." The sentence
structure is odd, but the meaning
is clear. Most early radio stations
hired their own musicians to avoid
these limitations. Later, there was
an understanding that having rec-
ords played on the radio would
actually increase the sale of pho-
nograph records, benefitting eve-
ryone, and eventually arrange-
ments were made to reimburse
musicians whose records were
used on the air.
By the 1930s, electric recording
and reproduction of phonograph
records provided the possibility of
recording radio programs in ad-
vance on transcription disks.
These were large records, typically
16" in diameter, that operated at
33 RPM, long before long-playing
records at this speed were offered
to the public. By using these tran-
scription disks, a 15-minute pro-
gram could be recorded without
interruption. Transcription disks
were largely replaced by magnetic
tape recordings in the 1940s.
Early broadcast stations transmitted at
5 watts; better vacuum tubes allowed
power to be increased.
WLW of Cincinnati was given an
experimental license for a 500,000 watt
transmitter, but the experiment was short
lived, and stations since have been limited
to 50,000 watts.
6
As radio broadcasting became pop-
ular, many companies were eager
to put a station on the air. A list of
radio stations included in the Fall
1925 edition of the Radio Listener's
Guide and Callbook shows an inter-
esting mix of stations, most owned
by schools, religious organizations,
radio shops, or retail stores. The
transmitter power of some of these
early broadcasting stations was as
low as five watts, and there were
only a few stations operating with
power levels above 500 watts.
There were only three stations
listed with power levels of 5,000
watts. The listener had many sta-
tions to choose among, but only a
few had enough power to break
through the static and provide en-
joyable listening.
By the mid-1920s, the Federal Ra-
dio Commission reassigned broad-
cast frequencies to avoid interfer-
ence, and eventually most stations
used at least 500 watts of trans-
mitter power. The development of
better vacuum tubes allowed trans-
mitter power to be increased. By
the 1930s, 1,000 watt and 5,000
watt stations became common. By
the mid-1930s, there were even a
few 50,000 watt stations, including
station WLW in Cincinnati, Ohio,
which was owned by Powel Cros-
ley, Jr. who also manufactured
Crosley radios. For a few years,
WLW had an experimental license
to operate a 500,000 watt trans-
mitter, but the Federal Communi-
cations Commission later terminat-
ed this license and limited all AM
broadcasting sta-
tions in the Unit-
ed States to a
maximum of
50,000 watts, a
power limit that
is still in effect
today.
Audio quality
was also a prob-
lem in the early
days. Carbon
microphones
were used, simi-
lar to the trans-
mitter section of
a telephone
handset. They
were not very
sensitive and
had poor fre-
quency response.
Fortunately,
better micro-
phone designs were developed and
sound quality improved. Harold
Black, an engineer with Bell Tele-
phone Laboratories, invented neg-
ative feedback in 1927 to improve
the performance of audio amplifi-
ers. This invention was originally
This photograph of the author’s 1937 Silver-tone shows the markings for police, foreign,
and amateur frequencies that were com-mon on many radios during the 1930s and
7
used for "repeaters" to amplify
long-distance telephone calls but
was later applied to audio amplifi-
ers for other applications including
radio broadcasting.
The technology of modulating the
transmitter signal with the audio
program material also improved.
Throughout the 1920s, a method
called Heising modulation was
used. It worked, but was ineffi-
cient, especially for high-powered
transmitters, and could not fully
modulate the radio frequency sig-
nal. A better method called Class B
Plate Modulation was developed
by Loy Barton, an engineering in-
structor at the University of Arkan-
sas, in 1930. This was the first
modulation method that provided
full 100% modulation. This im-
provement made AM radio signals
sound better to the listener. The
University of Arkansas radio sta-
tion, KUOA, was the first to use
Barton's invention, but it was later
adopted by all broadcasting sta-
tions.
The use of leased telephone lines
and phonograph recordings made
remote broadcasting possible. Ra-
dio broadcasts could be made live
directly from the sources of inter-
esting events, or could be recorded
for broadcasting later. An example
of this capability was the memora-
ble report of the crash of the Hin-
denburg air ship at Lakehurst, New
Jersey, on May 6, 1937. Radio an-
nouncer Herbert Morrison de-
scribed this shocking event as it
was happening. That emotional
broadcast is still available today on
the internet.
By the 1930s, radio was being used
by law enforcement organizations.
Initially, police departments made
arrangements with existing broad-
casting stations to interrupt their
programs with dispatches to their
patrol cars. The Chicago Police De-
partment used radio station WGN
for this purpose. Later, police de-
partments established their own
radio stations on separate frequen-
cies. Some were at the top of the
AM broadcast band, between
1,650 and 1,720 KHz. Others had
assigned frequencies between
2,400 and 2,450 KHz on the short
wave band. These frequencies
were often marked "Police" on ra-
dio dials, and listening to police
dispatchers appealed to the public.
I read a report in an old radio mag-
azine about a listener in Alaska
who enjoyed tuning into the Los
Angeles, California, police frequen-
cy, 1,712 KHz, when radio propaga-
tion conditions were favorable. He
learned the names of the police
dispatchers and could recognize
them by their voices.
By the early 1950s, nearly all law
enforcement organizations used
two-way radios operating on VHF
frequencies. The police bands
marked on the dials of old radios
are no longer used. My next article
will discuss developments that al-
lowed radio to move from the liv-
ing room to the automobile, allow-
ing broadcast listeners to enjoy
their favorite programs on the
road.
JIM COOK, the son of a radio techni-cian, became a licensed amateur radio operator at 15 and obtained commer-cial radiotelephone licenses before he was 20. He worked as a transmitter operator for two radio stations while studying electrical engineering at the University of Kansas. After graduation he became an electronic circuit design-
By the 1930s, broadcast radio was being used by
law enforcement; police made arrangements with
stations like Chicago’s WGN to interrupt their
programs with dispatches to patrol cars.
8
Crystals, diodes, and
transistors….my house to
the schoolhouse
By Bill Phillips, KD2BME
It all began with a crystal set. The year was 1952 and
my father brought home a kit. It had a card board base and the
parts were held together with pins. The circuit was the usual;
coil, crystal, ear phone and capacitor. The parts were joined by
strips of metal. The coil had an arm that slid in an arc along the
surface of the windings. The arm had very little effect as it
worked in only one position.
The crystal was another matter. It worked when the cat’s
whisker hit a sensitive spot on a crystal of galena. The galena
was protruding from solid solder that was filing a small cup. The
cat’s whisker was a short piece of thin tough wire that was used
Galena crystal
9
as a probe to randomly poke around the
crystal’s surface. When it hit a sensitive
spot you could hear a crackling sound in
the ear phone. If you could hold the end
of the cat’s whisker in that place, it was
possible to hear a station.
The set needed an antenna and a
ground. My bed room was overlooking
the back yard. I placed small holes at the
bottom of the window just large enough
to get the wire through and small enough
so dad wouldn’t notice. That hole al-
lowed me to stretch a wire the length of
the yard. Somehow dad noticed, he was
a keener observer then I guessed. If the
antenna hadn’t caught his attention the
ground wire would have. A heavy wire
coming down the side of the house con-
nected to a steel rod planted in the gar-
den mixed in between mom’s zinnias.
Then, it was time to listen. I held the
ear phone up, holding it in place with the
bail from a paint can. With a steady hand
and unlimited patience I poked the cat’s
whisker around the surface of the galena.
I spent a long time poking before I heard a
faint sound. Then finally, there it was a
radio station. After the time spent listen-
ing to a whisper I was able to identify the
station as WKBW the strongest station in
Buffalo. I didn’t know it at that time but
my great piece of technology was
doomed to receive that one station.
The dawn of semiconductors
If technology had stopped with the crys-
tal, I would have been happy to listen to
the only station on the air. Progress con-
tinued the boy next door got a diode. He
was four years older than I was and
would always find the next best thing.
Diodes met the dreams of any true radi-
oman. My success at building better crys-
tal sets was certain. My next model was a
splendid improvement. Mounted on a
board with a bigger coil, variable conden-
ser and that new diode. It was a marvel
of planning, a sight to look at, all neatly
spread out with the wire connections
twisted together. With great pride in my
advanced design, I was ready to hear all
the stations that I heard on our radio. I
picked up the earphone moved the arm
on the coil and heard nothing. I wasn’t
surprised because I hadn’t adjusted the
condenser. As I turned the shaft of the
condenser, I heard a station. It was
WKBW in Buffalo, where I lived. With
glee, I realized I had a real radio. I could
tune it and get any station I wanted. I
soon found out I could get the station I
wanted as long as it was old KB. That was
it, not much better than my original crys-
tal set.
It was three years later, when I saw a
drawing of a small radio using something I
never heard of. The transistor had been
born. I was taking a short course in elec-
tricity. I learned what a circuit was and
how to wire one. Best of all I learned to
solder.
My teacher was interested in electronics
and knew all about radio circuits. I found
a plan for a one transistor radio in “Boys
Life” magazine. I showed it to my teacher
who wanted to see one built. My first
experience with parts was a trip to a radio
parts store. I had never seen such a store.
It had shelves; of mysterious things, I was
hooked. I didn’t know what they were
but I wanted some. The man at the coun-
ter helped me get the parts I needed.
They were the usual; resistors, capacitors,
an adjustable coil and a small flat variable
condenser. The best of all was a transis-
tor, the CK722.
At home, I found a small plastic box, some
wires and a small battery. I drilled holes in
the box. Soldered the parts together plac-
ing them in the box with wires soldered to
the battery. I had a bolt on the side to
attach the antenna. For a switch, I ex-
tended two wires from the box I could
twist together to power the set. It
worked with a long enough antenna, I
could get any station I wanted and that
was, take a guess. That’s right, WKBW
from Buffalo.
10
Transistors were new, with a mystery that
goes with a break in discovery. My next
Idea to improve my radio was to make it
portable with a special antenna. It had
four wires each one spreading out along
my arms and legs. Today, that would be
stealth technology.
The best part was getting to show it off to
my friends. First, I took it to a Boy Scout
meeting. By then I had an earphone like a
hearing aid. I walked around the meeting
with only the earpiece noticeable. The
Scout Master came over to say, he didn’t
know I was deft. I went home knowing I
had a success with a radio like the one
spies have.
The next adventure would be at school. If
I could get away with it in some places, I
could take the radio to school. The rea-
soning was, why not? It would be great to
sit in class listening to the radio while the
teacher went on without any idea I was in
my own world. In the end, that was not
rewarding enough. The radio however,
had to be shown to my classmates.
Showing off wasn’t going to be good
enough, There had to be an advance in
technology to make it really exciting. The
radio was miniaturized, the earpiece
couldn’t be changed, what was left was
an improvement in the antenna. The
antenna wasn’t flashy enough and could
be improved. The radio needed an an-
tenna that was long and portable but
could be hidden when not in use. In my
room was just the thing, a slinky.
That morning, I set out for school with
expectation that this would be the most
remarkable thing to show. Ever since, I
brought a hollowed out book with a
squirt gun inside. I waited until English
class to show off my newest radio. The
classroom was on the second floor giving
me some height to drop the coil. I had
the radio tucked into my shirt pocket and
hidden in my book bag was my stealth
antenna. As I walked into class, I knew
this was going to be the day that my tech-
nical genius would make a lasting impres-
sion.
The class started as usual. Then contin-
ued with the teacher working on a class-
room project with the students gathered
around at her desk. That was the mo-
ment needed to start my demonstration.
My friends saw me get out the slinky and
knew I was up to something. I handed
the slinky to a friend who was by a win-
dow. He opened the window and
dropped one end the slinky down the
side of the building. He secured this long
bouncing spring to the window frame
with a hook. I passed a small wire to him.
He connected his end to the slinky, now
turned into an antenna, and then I con-
nected my end to the radio. I was in busi-
ness and the students huddled around
me weighting for the moment I heard a
station.
Suspense was building, it was quiet.
Then, there was a knock on the door. A
messenger passed a note to the teacher.
The teacher read it and looked up at me.
The students around her looked at me.
My friends around me sat down. There, I
was attached to a wire, attached to the
window with something almost out of
sight.
The note, it turned out was from a
teacher in the classroom below. Saying
something about a dangling object
bouncing around in front of her window.
I knew my teacher knew that I had done
something that needed an explanation.
The suspense had changed; it was now
the teacher who held the attention. The
sudden stillness, spoke for its self. The
climax came with the predicable phrase, “I’ll
see you after school”.
BILL PHILLIPS, who is retired, taught high
school physics and industrial arts. He is an
Extra Class ham as well as an amateur geolo-
gist.
“The boy next door
got a diode. He was
four years older than
I was and would
always find the next
best thing.”
11
Now We
Know….
Gravity Makes
Waves
By Prof. Alan B. Entenberg
On February 11, 2016, it was officially reported
that gravity waves were finally discovered after Albert Einstein
used the theory of General Relativity to predict their existence
almost exactly a century ago in 1916. (The discovery was pub-
lished at Abbott et al, Physical Review Letters 116, 061102
(2016).) The means for detecting them was the huge LIGO
(Laser Interferometer Gravitational-Wave Observatory) appa-
ratus consisting of one station in Livingston, Louisiana, and a
second in Hanford, Washington. Each LIGO apparatus is a light
interferometer with a perpendicular set of 4-kilometer arms
with mirrors. The setup can detect relative changes in the
length of these arms to a distance smaller than the 10-15 meter
diameter of a proton. The discovery was announced after obser-
vations at one of these stations were confirmed at the other.
Both LIGO observatories simultaneously received nearly identi-
cal signals on September 14, 2015 at 5:51 am Eastern Daylight
Time.
Scientists believe that these waves were generated from the
collision of two “black holes” over ten billion years ago at a dis-
History in the Making
AWA Gateway
12
tance of several billion light years from
our place in the universe, according to the
reports. As early as 2005, Dr. Manuela
Campanelli of the Center for Computa-
tional Relativity and Gravitation (CCRG) at
the Rochester Institute of Technology
(RIT) performed computer simulations of
two colliding black holes. The simulations
predicted a “ringing signal” of the gravita-
tional force field that would propagate to
Earth from such an event. The signals
detected by the LIGO systems were nearly
identical to more recent simulations by
Manuela and other members of the CCRG
group that she directs at RIT. Manuela’s
words were “I couldn’t believe it the first
time I saw what LIGO had detected and
how close it looked to the waveform we
had modeled on a supercomput-
er.” (Athenaeum, News and Insight from
Rochester Institute of Technology, Volume
7, Number 5, April-May 2016, Page 6.)
Shown nearby is an illustration (from the
LIGO website) of the simulated merger of
two black holes with the resulting strain
waveform for one of the LIGO arms.
Strain is the ratio of either the elongation
or compression of one of the arms divided
by the initial 4 km length.
The strain graph shows what happens to
either 4 km arm of the interferometer.
The black holes are approaching each oth-
er at about a third of the speed of light.
The whole merger is over within less than
half a second! Close to identical strain
signals were observed by each of the two
LIGO detectors in Hanford, Washington
and Livingston, Louisiana.
What does this all mean?
As you probably know if you are a radio
enthusiast, a wave can be viewed as a
“propagating disturbance” in a particular
medium. For example, if we pluck a
13
clothes line, the distortion will propagate
back and forth until the energy that is
stored in the distortion gradually disap-
pears because of friction. Likewise, when
a rock falls into the center of a placid lake,
circular ripples will propagate outward
from the point where the rock hit the wa-
ter. Similarly, sound can propagate out-
ward in spherical wave fronts from the
point of an explosion.
Electromagnetic Waves
Electromagnetic waves, capable of propa-
gating through a vacuum, were predicted
on purely theoretical grounds by the
equations of James Clerk Maxwell over
150 years ago. In 1888, Heinrich Hertz
first generated electromagnetic waves
(the propagation of energy through empty
space) with a spark gap. Radio waves are
one form of electromagnetic waves; light,
x-rays, and microwaves are other exam-
ples. Each kind of wave corresponds to a
different frequency range. Eventually,
Guglielmo Marconi read of Hertz’s work
and developed a method for sending out
code signals over distances of many miles.
The basic mechanism for producing elec-
tromagnetic waves is to make an electric
charge (usually negatively charged elec-
trons) oscillate back and forth with a par-
ticular frequency, f. Energy must be sup-
plied to make the electrons go back and
forth. Much of the supplied energy is radi-
ated outward in spherical electric force
field wave fronts which move at the speed
of light, c = 3.0 x 108 m/s. The relation
between the speed of the wave and the
frequency of the source is c = f where
is the wavelength of the wave. For ordi-
nary AM radio waves, the frequency range
is from about 0.8 MHz to about 1.6 MHz.
The corresponding wavelengths would be
about 400 m to 200 m, respectively.
These electric field wave fronts are detect-
ed when they pass through a metallic con-
ducting material, such as an antenna wire,
thereby causing the electrons in the an-
tenna to oscillate at the source frequency.
Gravitational Waves
In principle, gravitational waves should be
similar to electromagnetic waves. A very
simplified mechanism for producing them
is to supply energy to a mass and cause it
to oscillate back and forth with a particu-
lar frequency, f. Gravitational “force field
wave fronts” will radiate outward in the
same way that electromagnetic wave
fronts propagate outward from an oscil-
lating electron. They will even move with
speed of light, c.
The difficulty is that they will be extremely
hard to detect! This is because they are
relatively weak— very weak.
Let’s compare the gravitational force of
attraction to the electrical force of attrac-
tion for a fundamental system like the
hydrogen atom. In the simplest model of
the hydrogen atom, the positively charged
proton (charge = +e = +1.6 x 10−19 Cou-
lomb) is orbited by a negatively charged
electron (charge = −e) in a way similar to
the way the moon orbits the earth. Cou-
lomb’s Law gives the electric force of
attraction between the electron and the
proton.
Felec = kelec qe qp / r2
where qe is the charge on the electron, qp
is the charge on the proton, and r is the
distance between the electron and the
proton. The constant kelec is the Coulomb
constant. On the other hand, Newton’s
Law of Universal Gravitation gives the
gravitational force of attraction between
the electron and the proton.
Fgrav = kgrav me mp / r2
where me is the mass of the electron, mp is
the mass of the proton, and r is the dis-
tance between the electron and the pro-
ton. The constant kgrav is the Universal
Gravitation constant. If we take the ratio
of the electric force to the gravitational
force, the denominators cancel and we
obtain the following:
Felec / Fgrav = (kelec qe qp) / (kgrav me mp) ≈
1040 !!!!
The ratio of the electric force to the gravi-
tational force is a huge number. The ratio
is more than “a trillion times a trillion
times a trillion.” (This calculation can be
easily reproduced with the fundamental
constants found in any introductory phys-
ics book.) Gravitational waves are hard to
detect simply because the gravitational
force is so much weaker than the electric
force.
Here’s another way to look at it: The hu-
man eye can sometimes “see” the wave
quantum or “photon” emitted when a
single electron moves from a higher orbit
to a lower orbit in a hydrogen atom.
When this happens, we say that a
“photon” has been absorbed by an elec-
tron in the retina. But, there is no way
that we could detect the presumed corre-
sponding “graviton” quantum which may
also be emitted from the downward mo-
tion of the electron mass. Its effect on an
electron in our retina would be more than
“a trillion times a trillion times a trillion”
weaker!
Because gravitational force is so much
weaker than electrical force, we need to
14
have a much, much more massive set of
objects generate a wave front in order to
detect it. Two black holes whose gravita-
tional attraction allows them to orbit
around each other will do the trick. (It is
now believed that our Milky Way galaxy is
“invisibly” held together with the gravita-
tional field produced by an enormous
massive black hole at its center. Typically,
a black hole might have a mass over a bil-
lion times that of our sun.) If the mutual
orbit of two black holes is unstable, then
they could collide with each other and
produce a sufficient gravitational disturb-
ance that could be observed many light
years away.
That’s what may have happened here.
Simplistically, the colliding black holes
could be viewed as basically a “huge natu-
ral oscillator,” and the two LIGO stations
in Washington and Louisiana as two big
receiving antennas. When the gravitation-
al disturbance passes through one of the
LIGO receiving apparatus setups, each arm
will periodically elongate and contract,
relative to the other arm, by less than the
10−15 meter diameter of a proton. Amaz-
ingly, the optical interferometry of LIGO is
capable of detecting this distortion!
ALAN B. ENTENBERG, Ph.D. taught and did
research for over thirty years in the Physics
Department at the Rochester Institute of
Technology (RIT). He received his Ph.D.
from the University of Rochester in High
Energy Physics and later worked on de-
tecting neutrinos interacting with protons
at the University of Pennsylvania. He also
worked on the use of laser beams to liber-
ate nuclear fusion energy from hydrogen
isotopes at the University of Rochester. He
is currently Professor Emeritus in the
School of Physics and Astronomy at RIT.
Funded by the National Science Foundation, LIGO was designed
and constructed by a team of scientists from Caltech and MIT.
In an effort to detect passing gravitational waves, researchers
bounce high-power laser beams back and forth in each arm.
Passing gravitational waves alter the length between the mir-
rors in the LIGO arms, which the lasers detect. There are two
LIGO sites; the Hanford, Washington, LIGO site is shown here.
Credit: NASA, LIGO Laboratory.
15
Other Clubs
AWA Gateway
·The following is a non-exhaustive listing of other vintage and
antique radio clubs, including some detail as supplied by the
clubs themselves at various times in the past. The accuracy of
the detail is not guaranteed. Readers are advised to check the
clubs’ websites or to contact the clubs directly for current, com-
plete, and accurate information; and if you are an officer of a
club, and you wish to supply or update a listing, please contact
us . — Ed.
The Antique Radio Club of Illinois (ARCI) — Meets bimonthly.
Meets generally held at the American Legion Hall, Carol Stream
IL but meets in June in conjunction with the 6-Meter Club of
Illinois at the DuPage County Fairgrounds and once per year for
Radiofest, this year at the Medinah Shriners, Addison, IL . Check
web-site for schedules, details and maps.) Contacts: President,
John Stone, arcipresident@com; general information, clubinfo@
antique-radios.org. Website www. antique-radios.org.
Antique Radio Collectors of Ohio — meets first Tuesday of each
month at 2929 Hazelwood Ave., Dayton, OH (4 blocks east of
Shroyer Rd. off Dorothy Lane) at 7 p.m. Also annual swap meet
and show. Membership: $10.00 per year. For more info, contact
Karl Koogle: mail to above address; phone (937) 294-8960; e-
mail KARLKRAD@ GEMAIR.COM.
·California Historical Radio Society —For info on current
meetings and events, see www.californiahistoricalradio.com.
·CARS, the Cincinnati Antique Radio Society — Meets on the
second Wednesday of each month at Gray’s History of Wireless
Museum, which is part of The National Voice of America Muse-
um of Broadcasting, Inc., located in a building that is now on the
National Historic Register at 8070 Tylersville Road, Westchester,
Ohio. 45069. For more information contact Bob Sands at (513)
858-1755, or [email protected].
·Carolinas Chapter of the AWA — Hosts “mini-swap-meets” plus
an annual conference, “Antique Radio Charlotte,” on the 4th
weekend in March. For more info, visit the website at CC-
AWA.ORG or contact Ron Lawrence, W4RON, Chapter President,
P.O. Box 3015, Matthews, NC 28106-3015; phone (704) 289-
1166; e-mail [email protected].
·Central Ohio Antique Radio Assn. – Meets on the third
Wednesday of March, June and September at 7:30 p.m. Swap
meets: “Cabin Fever” in January and outdoor tailgate in July.
December Christmas party. For more info contact Barry Gould at
614-442-1518 or Dave Poland at 614-890-5422 or http://
coara.org/.
·Delaware Valley Historic Radio Club —Meeting and auction be-
gins 7:30 p.m. on the second Tuesday of each month. Location:
Telford Community Center on Hamlin Ave. in Telford, PA. Annual
dues: $15.00, which includes a subscription to the club’s month-
ly newsletter The Oscillator. For more info contact Delaware
Valley Historic Radio Club, P.O. Box 5053, New Britain, PA
18901. Phone (215) 345-4248.
Houston Vintage Radio Association (HVRA) meets the fourth
Saturday (January thru October) at Bayland Park 6400 Bissonnet,
9 a.m. in SW Houston. Each meeting includes an auction and
program. Annual two-day convention held in February includes
three auctions, old equipment contest, technical talks, swap
meet, and awards banquet. One day MEGA auctions held in the
spring and fall. A newsletter, The Grid Leak, is published bi-
monthly. Event postings, announcements, photos and other
features are available on HVRA website: www.hvra.org. Mem-
bership is $20/yr. Address: HVRA, P.O. Box 31276, Houston TX
77231-1276 or call Bill Werzner, 713-721-2242; email:
·Hudson Valley Antique Radio and Phono Society [HARPS] meets
the 3rd Friday of the month 7:30PM at the Episcopal Church of
Suffern Annex, 65 Washington Ave., Suffern N.Y. 10901 for info
contact Rev. Dale Cranston at (845) 357-1615 or
·Indiana Historical Radio Society — Active since 1971. Meets in
Feb. (Lawrence), May (2-days, Kokomo) and Oct. (Greenfield).
Flea market, old equipment contest, and auction at all events.
Meet details and club info at website
www.indianahistoricalradio.org. $15.00 annual dues includes
the IHRS Bulletin published quarterly. Contact Herman Gross,
W9ITT, 1705 Gordon Dr., Kokomo, IN 46902, 765-459-8308,
email w9itt@ comcast.net.
·London Vintage Radio Club — This Ontario, Canada club meets
in London on the first Saturday of January, March, May, and
November. Annual flea market held in Guelph, Ontario in June.
Contact: Dave Noon, VA3DN, 19 Honeysuckle Cr., London, ON
N5Y 4P3, Canada. Email: [email protected]. Website: http://
lvrc. home-stead.com/index.html.
16
·Mid-Atlantic Antique Radio Club (MAARC) — Meets monthly,
usually on the third Sunday of the month at the Davidsonville
Family Recreation Center in Davidsonville, MD. (But meets once
or twice a year in Northern Virginia—check website for sched-
ules, details and maps.) Contacts: President, Steve Hansman,
855 Arundel Drive, Arnold, MD 21012, (410) 974-0561, email:
shans01 a@ comcast.net; Membership Chair, Geoff Shearer,
(703) 818-2686, email: [email protected]. Website
www.maarc.org.
·The New Jersey Antique Radio Club — Meets the 2nd Friday of
the month 7:30 p.m. at either Info Age 2201 Marconi Rd. Wall
Township N.J. 07719 or Bowen Hall, Princeton University. We
hold three annual swap meets and four seasonal repair clinics.
Visit the club’s web-site for details www.njarc.org or contact
NJARC President Richard Lee (914) 589-3751 or presi-
·Northland Antique Radio Club (Minneapolis/St. Paul) — hosts
four events with swap meets each year (in February, May, Sep-
tember and November) including an annual conference, “Radio
Daze,” for two days in mid-May. Annual dues are $12.00, which
includes a subscription to the club’s quarterly newsletter. For
more info, visit our website at www.northlandantique - radio-
club.com.
·Northwest Vintage Radio Society — Meets the second Saturday
of each month at Abernethy Grange Hall, 15745 S. Harley Ave.
Oregon City, OR. Meeting starts at 10:00 a.m. Membership
$25.00 per year. Guests welcome at all meetings and functions
except board meetings. Spring show, the second Saturday in
May. For more information, contact Mike McCrow 503-
730¬4639; e-mail: [email protected].
·Oklahoma Vintage Radio Collectors —Meets second Saturday of
each month, (except for April, October, and December), at
Hometown Buffet, 3900 NW 63rd St., Oklahoma City, OK. Visi-
tors welcome. Dinner/Socializing, 6 p.m., meeting, 7 p.m. Swap
meets on second Saturday in April and October at 8 a.m., Mid-
west City Community Center, 100 N. Midwest Blvd., Midwest
City, OK. Membership $15/year including monthly Broadcast
News. Info: contact Jim Collings at (405) 755-4139 or jrcradio@
cox.net. Website: www.okvrc.org.
·Ottawa Vintage Radio Club — Usually meets the second
Wednesday of every month (except July and August) in the Con-
ference Room, Ottawa Citizen, 1101 Baxter Rd., Ottawa, Ontario,
Canada. Auctions in October and May. Call Paul Guibord (61 3-
523-1 315), or check www.ovrc.org for details.
·The Pittsburgh Antique Radio Society welcomes visitors to our
Saturday flea markets, contests and clinics held at least four
times yearly. A fall auction is included in September and our an-
nual luncheon program is on the first Saturday in December. An
annual Tri-State Radio Fest is held in April. Our journal, The Pitts-
burgh Oscillator, is mailed quarterly. For more information visit
us at http://www.pittantiqueradios. org, email President Chris
Wells at [email protected], or phone Treasurer
Tom Dixon at 412-343-5326.
·Society for Preservation of Antique Radio Knowledge (SPARK) —
Meets monthly at Donato’s Pizzeria, 7912 Paragon Rd., Center-
ville, OH. Annual swap meet. Membership $15/yr. Write SPARK
Inc., c/o Dan Casey, 10075 Morrow-Rossburg Rd., Pleasant Plain,
OH 45162 or call Dan Casey at (513) 265-8466 or e-mail dansra-
dioland@ gmail.com
·Texas Antique Radio Club — Meets alternate months in Kyle
and Shertz, TX. Contact: Doug Wright, 625 Rolling Hills Dr., Can-
yon Lake, TX 78133. Email: [email protected]; website
www.gvtc.com/ ~edengel/TARC.htm.
·Vintage Radio and Phonograph Society (VRPS) meets monthly
on the third Saturday. Located in the Dallas, Fort Worth
Metroplex, our current activities are annual convention, auc-
tions, swap meets, repair training sessions and monthly pro-
grams. For details visit our website www.vrps.org, or by con-
tacting VRPS President Jim Sargent at (817) 573-3546 or bsar-
17
About Us
AWA Gateway
The Antique Wireless Association is an organization of about 1600 international members linked by a common interest in the histo-ry of electrical and electronic communications. AWA members come from all walks of life and our ranks include teenagers, octoge-narians, and beyond in both directions. At one of our meets, you might find yourself shaking hands with a retired broadcast execu-tive or military electronics specialist, an engineer in a high-tech electronics firm, or an eager young person looking for advice on restoring his or her first radio.
The organization was started in 1952 by Bruce Kelley, George Batterson, and Linc Cundall—amateur radio operators and radio col-lectors from upstate New York. Their initial goal was to establish a museum where they could collect and preserve early wireless and radio equipment and historical information before it was lost to future generations. Decades later, their legacy continues to motivate our members.
Some of us are most interested in the technical background behind the epoch-making discoveries that now make it as easy to com-municate across the globe as around the corner. Others enjoy the romance surrounding the men and institutions that put these discoveries to work: the maritime radio operators who averted disasters with their alert ears and quick thinking; the short-wave stations that radiated glimpses of exotic cultures and mindsets; the giant radio networks that delivered unparalleled entertainment and timely news to our homes while hawking toothpaste, cigarettes and soap flakes.
Though AWA members share this common interest, which many can trace back to early child-hood, they express it in different ways. Some of us collect radio-related literature and manuals. Others collect and restore hardware: Morse keys and sounders, battery radios of the 1920s, telephones, advertising signs, cathedral and console radios—you name it! Collections can become very specialized, restricted to such things as radio components crafted of shiny Bakelite and gleaming brass or perhaps the fragile and intricate vacuum tubes that made the communications miracles possible.
Among our members are meticulous craftsmen who enjoy replicating vintage receivers and/or transmitters. Those who are li-censed amateurs frequently operate such equipment in special communications events sponsored by the AWA.
In addition to the commitment to the preservation of historical artifacts and background materials at our Museum, AWA also pub-lishes The AWA Journal and The AWA Review. The Journal is a quarterly publication that gives our multi-talented members an out-let to share their historical research, equipment restorations, troubleshooting and servicing tips and other information of common interest. The AWA Review, which also publishes member contributions, contains more extensive and scholarly papers. It is pub-lished once a year.
The AWA Gateway is the latest addition to the AWA family of publications. It’s delivered electronically and free of charge—downloadable from our web site www.antiquewireless.org.
Our content is targeted at those who may not be familiar with the AWA and who perhaps are just becoming interested in the histo-ry, collecting or restoration of vintage communications gear. For that reason, our technical articles are more basic than those in our other publications and our articles about AWA generally do not assume knowledge that that only those familiar with our organiza-tion might have.
The AWA also sponsors a four day annual convention in August featuring technical presentations and forums, a large auction, an awards banquet, an equipment and artifact competition, a book sale, and an active flea market. The convention affords attendees plenty of time to renew and make friendships, time to engage in long conversations on col-lection, preservation and all other as-pects of the hobby.
The AWA Museum campus is located in Bloomfield, New York. Membership in the AWA includes free admission to the world fa-mous facility. It is crammed with too many treasures to describe here, but you can see some of the exhibits on our web site www.antiquewireless.org.
The AWA is chartered as a non-profit organization in New York State, an IRS 501(c)(3) tax-exempt corporation, and is a member of the American Association of Museums. To learn more about AWA or to join our organization, visit the AWA website.
DONATING ARTIFACTS TO THE AWA
You may have artifacts that you are interested in donating to the AWA. We would be pleased to discuss any possible donation. Please call us at (585) 257-5119.