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Good Morning ladies and gentlemen
and many friends I see here. I miss one friend, the late
professor Ray Yarborough whom I studied under many year ago when
I worked at Memorex. I started here at the University in
the early bird program. Where you get up fresh at six in
the morning, and class is from seven to nine. Rather refreshing
in certain ways. Before I start showing the sequence of
slides, there is one for your attention. A book was just
published that was edited by Daniel, Dennis Mee and Mark Clark.
Dr. Mee is here today so if you have any questions or you want
to see a copy of the book they are on display outside.
There are about twenty chapters covering various aspects of magnetic
recording and it is delightful reading and not too heavy but
it gives a look in to the people contributions over the years.
Because more than any other industry I think this one has a variety
of personalities and people that are delightful, wonderful, honest
individuals that work well together. That is exemplified
in that book. I should not forget that there is another
earlier book Marvin Camras that also gives some insight into
some of the early developments of magnetic recording.
At this point I say thank you to Al Hoagland
for inviting me to this occasion, I appreciate it. I want
to start by thanking Mr. Kilapatrick for the elegant introduction
remembering so wonderfully the Dane Valdemar Poulsen was seen [slide 1] on a medal that
was issued about forty, fifty years ago. It was intended
to be an annual event where some young inspiring students or
engineers would receive it for due diligence.
What I will show you are some pictures that
will supplement the invention of magnetic recording. The
gentlemen who brought the magnetophone to the United States,
Jack Mullin, who lives happily retired in Camarillo. He
has a garage full of various machines in fine operating condition
among them the magnetophone. He recorded a tape in 1947.
That was the first actual tape made for broadcast by Bing Crosby
Enterprises. You will hear the delightful voice of Bing
Crosby singing assisted by no other than Jimmy Durante.
It is a little unusual entertainment.
I gave this presentation earlier this
year at an IEEE conference on Magnetic Media. The Maastrict
paper will be published in spring in the Journal of Magnetism
and Magnetic Materials. There you will be able to find
that paper. Some other aspects of the invention of magnetic
recording are covered in a book published by the Academy of Sciences
in Denmark, it is a Danish Edition. It is on the telegraphone
and the ARC transmitter later, about which little is published.
With the hundred year anniversary of magnetic recording the academy
decided to republish it. Friends in Denmark and also over
here in the states sponsored it and they looked around for translator
and they looked at me and said you are probably the only one
that can still write Danish. Which is not quite true, my
Danish is vintage 1955. The book was easily translated
and has been issued just for conference. Valdemar Poulsen,
who died in 1942.
By the way I
have a sample Jack gave me, reel to reel tape. This is
the original German tape made in 1943. It is a mass band
as it was called. It is not coated on a PVC film as they
were originally. In 1942 the allied forces wiped out the
plant that made tapes for the AEG company. They had to
switch immediately to something else and they came up with the
idea of just using plastic throughout so there is no base film
built. It is different and it is wonderful handling in
the tape machine by the way because you don't have to fight two
different materials. Valdemar Poulsens invented magnetic
recording was proceeded by, whether he knew it or not we don't
know, but there was an American named Oberlin Smith that wrote
a couple of elegant dissertations on the possibility of recording
magnetic sound. That is covered in Mee's and Daniel's book.
I have had to fend off many efforts among others of the audio
engineer society's effort to push Poulsen of the chair as inventor
and replace it with the local man Oberlin Smith. I am a
American citizen but when the Dane comes awake in me, then I
have to go out and defend the good of Valdemar. [slide 2]
He was not a very studied man except in areas
other than mathematics, because he disliked mathematics textbook
because he found sentences like “it is easily” seen
where after the author would describe the most difficult thing
in the whole book just simplified to two lines. He had
a great mistrust of mathematics but he studied chemistry and
physics and also natural science as matter of fact he graduated
as a student with a grade "A". It has been mentioned
that he flunked the admissions to Poly Tech University where
I later graduated from. He never did apply as a matter
of fact. He foresaw it for hopeless but he did take some
preparatory courses. He ended up working for the telephone
company in Copenhagen. His may be the difference between
what Poulsen did and what Oberlin Smith tried to do. Oberlin
Smith didn't really have any purpose whatsoever for such a machine
to record sound or what have you with, Poulsen did. He
and other people were annoyed with the fact that people did not
have any way of leaving a phone message if the recipient was
not at home. That is why we all have our answering machines
today. That was the target: an answering machine.
It did not have to be very long playing time but what ended up
was less than a minute and that was inadequate. By the
way I am going to spare you for a recording of Kaiser Franz Joseph
because of all the times I have demonstrated no one has ever
understood a word of it. It is in German so you can envision
it. I am saving a minute here for something else.
Poulson found in one experiment that striking
a magnet down along a iron plate and then spraying iron filings
on it that iron filings would stick to the places where he had
touched it. [slide 3] This got him interested in
building his machine as a drum recorder and he also built a another [slide 4] wire recorder
actually using a three millimeter wide tape. These
machines can be seen. [slide 5] Again I am delighted
that IBM sent someone over to photograph these machines I have
pictures of them better than these to show later the drum is
from one end to the other covered with a tightly wound piano
wire one millimeter diameter of steel. The head has two
pole pieces that grasp the wire on each side so it is kind a
cross wise magnification pattern which you can playback.
But look, no amplifiers, that did not materialize until 1918
to 1920 when Deforrest came up with the vacuum tube. That
also had a great effect on another aspect of Poulsens work namely
the wireless transmitter which we shall come to shortly.
He received in Paris, a Grand Prix medal in the year 1900, for
the recorder, named the telegraph.
He also ventured on to make a disk
type recorder. [slide 6] He envisioned
the reason the disk is nice is because you can put it in a envelope.
It had a playing time of about two minutes or so, which was kind
of adequate. I don’t know if Mr. Shugart has arrived
yet but he will be delighted to verify that the diameter chosen
for hi-disk was five and a quarter inch. So that was right
on.
Here is a spool machine
[slide 7] were we move wire from one spool to another.
Companies were built and floundered. All this is covered
in the book on the hundred year history of magnetic recording
were Mark Clark wrote three or four chapters on that topic.
It is a most intricate mechanism [slide
8] that really this is a mechanical engineers delight and
everybody else’s nightmare I am sure. One of the
things with these wire recorders is if it broke it would be a
great problem to fix it. Valdemar Poulsen was assisted
in his many further years after the invention of magnetic recording.
He was twenty nine when he invented magnetic recording by professor
P.O. Pedersen. Got his patent issued world wide.
No questions asked it was a clean patent. [slide 9]
Two years later he got the grand prize at
a world fair in Paris. He came into the professors home
in Copenhagen and there he met Mr. P.O. Pedersen who later became
a professor at the Poly Tech. He was Poulsen's analyst
you might say. He was not an inventor but he would be the
one that would take Valdemar Poulsen's ideas and tear them apart
or support them and analyze them in a analytical fashion and
that worked extremely well throughout the rest of his life till
he passed away in 1942.
[slide 10] Here
is another machine. That was thirty five years later.
About 1902 his interest in magnetic recording went over to wireless
radio. Because there was no furtherance of magnetic recording
per say. The companies he help found he made some money
off them and many trips to the United States where some of the
companies were located and lived a quite nice life, particularly
when his wireless business came about. Nothing was done
about magnetic recording. The Germans picked it up.
For instance Lorenz. They started building machines and
here is a 1935 model.
[slide 11] Here
is the Marcone-Stille machine. Stille was a German engineer
who worked with another engineer who's book many of us had as
a first text book in magnetic recording by Mr. Begun. This
machine used a quarter inch wide steel ribbon with reels that
were about three almost three feet big, and running at a phenomenal
speed of ten miles per hour or so. The heads were up on
top and the whole thing was about as tall as a person is.
I have been told by Eric Daniel that he was once worked with
this machine at BBC in London. Then we were broadcasting
a speech by her majesty. That is an important event and
nothing must disrupt it. Well the speech was fifteen minutes
long and about two minutes in to the speech the tape broke.
Theses machines were in small rooms, and you had this steel band
coming out like a sabre coming at ten miles per hour, so unless
you want to be cut to pieces you get it out of the way.
Eric then got a hold of his tape took it out in the corridor
up and down and up and down and he figured out he ran two miles
in fifteen minutes which is pretty damn good. So he feels
that normally in the Olympics you run that kind of length and
then you get a medal, he should have had the medal because he
after all broke the tape.
[slide 12] The
Marcone-Stille machine was used a lot. The wire
recorder came in 1947. Now thin wire was used. As
mentioned in the introductory to Kilapatrick some of these machines
were used in the military playing back and transmitting messages
at five times the normal speed. After high speed recording
the message was clear at one fifth the recording speed.
This was one method of encrypting. No one could decipher
a message coming in at that speed.
[slide 13] Here is a wire recorder from 1948 fromt Bang
& Olufsen in my hometown Struer in Denmark. They managed
to produce a wire recorder. After that everybody else thought
of doing it. [slide 14] Here is the magnetophone 1935.
The Germans built the first tape machines and no one knew about
it kept under the wraps in preparation for the second World War.
That was number four machine that you saw and here [slide
15] is number eight of the military version. They had
another one, radio version, that had a AC Bias in it. [slide
16] That AC Bias machine is the one that was brought back
to the United States. [slide 17] Brush Sound Mirror is
another American made recorder. A very famous broadcast
machine [slide 18], the PT6, became the buzz word for
radio recording after the late forties. Here is the Ampex
model 200 [slide 19], which was a derivative of the magnetophone.
That was the one that started Ampex and Crosby Enterprises that
later became the Mincom division 3M. [slide 20]
Back to 1902. By that
time Poulsen had got another idea named the ARC generator.
This brings about the broadcast era you might say. At that
time there was only one transmitter available, and that was the
Marconi transmitter [slide 21] that worked on a sparc,
that would develop between two poles. Tuned over that sparc
vs. an L-C circuit that would send out spikes in the atmosphere
that would travel around the world with a spectrum very broad.
You could only have one transmitter to to tune into. It
was impossible to work with. More than that it was a severe
limitation. Well, Poulsen [slide 22] met a British
gentlemen, Mr. Duddel, who was tuning a tuned circuit that had
a capacitor and an inductor. He found that he could, by
varying the capacitor, tune it and send out various frequencies,
fairly sharply, but no way of doing it with amplititude modulation.
[slide 23] What Poulsen concocted was difficult
to see, but he now had an L-C circut with an ARC, no longer an
sparc but a continuous ARC, glowing between two carbon electrodes.
He felt that alcohol fumes would be nice. He had seen the
effect of alcohol on people and found it very enlightening.
So maybe that would help that tuned circuit and it did.
Later he switched to hydrogen. He now had a tunable transmitter
and he could amplitude modulate this transmitter. That
was 1902. Needless to say he dropped everything else, and
[slide 24]
went ahead with his work on the ARC generator. [slide 25]
He was supported by wonderful people. One gentlemen
who supported him all the way through his life he was a Mr. Dessau.
He was the president of Tuborg Breweries. What a delightful
way to use the profits from that product.
[slide 26] An
unknown Dane to any but a few around here is Mr. Peter Jensen
who actually has credit to inventing the loud speaker.
I think that might be something one would want to research but
at least he got named [slide 27] for the dynamic moving
coil generator that was used in his speakers [slide 28]
that became known as Magnavox. He was retained by Valdemer
Poulsen. They started building [slide 29] transmitters
this one in Copenhagen. Then they built the receivers a
hundred miles away and another one two hundred miles away.
They finally ended up in Ireland and it worked well. Now
they started selling transmitters and receivers all over the
world. Some of the places would just commission ([slide
30] here is one that came from Palo Alto of all places) and
this was the set up before shipping out of Denmark. In
Chicago [slide 31] transmitters built, Panama Canal [slide
32] transmitter, and of course California [slide 33]
The most impressive [slide 34] one of them all is a 300
kilowatt transmitter in Java for transmission back to Holland.
I don't believe many know about this aspect of Valdemar's life.
One interesting aspect of the German and the
British naval forces engaged in a battle of Chile (I don't know
what the heck they were doing over there but they found a place
to battle) was that the English were pulverized because of
the Germans had complete intelligence which the English had not.
Why? the German used Lorenz transmitters. Lorenz transmitters
were tunable ARC generators, but the British navy was still using,
faithful to Marconi, the sparc generator and only one ship at
a time could transmit. Anybody could pick it up.
So there are many interesting facets of that.
OK, here [slide 35]
is bust of Valdemar Poulsens that you will find in the Engineering
Society's building in Copenhagon. I would like to show
pictures of a visit a few months ago before the conference in
Maastricht. I went to Copenhagen and here [slide 36]
is Valdemar Poulsens’ second generation. That is his
nephew, Valdemar. He has a Ph.D. in geology of all things.
He has a spark and a humor that is absolutely delightful.
His nephew Kell Poulsen [slide 37] looks much more like
Valdemar Poulsen did. The two were together with IEEE’s
head [slide 38] of the E group in Denmark. Mr. Frank
arranged for a tour to the Technical Museum north of Copenhagen.
Look at some photos here pulled from the Poulsen family archives.
Here [slide 39] is little Valdemar Poulsen. He was
the favorite child. He had a fairly happy life as a child
but unfortunately he lost his mother at the age of four, which
marked him for life in a way. His sweetest memories were
of going with a nurse over in to the park called Kings Garden
in which there was a fountain with a little boy trying to control
a swan twisting its neck back, and somehow or another it made
a impression for life. I am not sure what simpleness is
to be found in it but it was a favorite thought of his.
[slide 40] This as a young man. As I said he did
not flunk the state exams but he did not take the right exams.
[slide 41] This is
the medal he received at the Gran Prix in Paris. Visiting
at that, as was mentioned in Dennis Mee's book, was Alexander
Graham Bell. [slide 42] Emile Zola was another visitor.
[slide 43] This is out of the original visitor's book from
that exposition. There are not many pictures of Valdemar
Poulsen, but there is one here. [slide 44] He was
living a good life in Copenhagen. Wherever he was encountered
by a visitor or guest he would mingle with everybody and talk
about anything in a jovial and happy fashion. At lunch
time he met with his old friend P.O. Pedersen and that continued
up for many years.
[slide 45] Here
he did have the pleasure of seeing a tape machine. This
is a tape machine built for the Olympic games in 1936.
It was built by Lorenz in Berlin. It used a steel tape
that was coming of age.
[slide 46]
Then at his latter days of course he had his grandchildren and
he had a family movie. I will spare you a showing because
it is strictly Danish spoken and Danish is not really
a language, it is more like a throat disease. It reminds
me very much of Dutch. A Dutchmen speaking backwards can
be understood by a Dane. [slide 47]
Here he is and you can see that age is beginning to show.
No magnetic conference
is complete without a conference dinner and a visit to a near
by castle. So we made a mini conference [slide 48]
out of Copenhagen and ventured up to the technical museum in
Elsinore. You recognize many of your friends here.
He is Professor Munson in the back here and I think we got Dennis
Mee and Eric Daniel and this is Mark Clark, who is a professor
up in Washington.
[slide 49] Here
we have a row of the machines that Mr. Brejnegaard, leader of
the museum, has gracefully taken out of storage and brushed them
up, so they were in top notch condition to be shown and operated.
[slide 50] Dennis Mee and Eric Daniel got a chance to
look close up [slide 51] at these machines. The
hand crank [slide 52] was necessary to wind a spring wound
motor in it like a phonograph motor. Remember those nasty
things would snap back and break your fingers. [slide 53]
[slide 54] Here
we see again two grandchildren and the third gentlemen is the
grandson of P.O. Pedersen. The three of them still see
each other regularly and they have good hours together.
Here is a castle we
visited and that is the Frederiksborg castle. [slide 55]
Up on the fourth floor we stopped and looked [slide 56]
in vein for the painting of Valdemer Poulsen and Pedersen but
it was out for restoration. So we did not get to see it
but a nice walk up and down a flight of stairs.
[slide 57] Let
us go in to Copenhagen and find another castle, Rosenborg.
It has that fountain with the little boy and the swan. [slide
58] I will leave it for your imagination what he is
going to do with that swan. But he has the intent of curtailing
it some how before.
That is a brief look
into a different Valdemar Poulsen than you see written about
in any place else. I felt privileged to have visited
his grandchildren, and thank you for listening.