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This manuscript is being made available for research purposes only. All literary rights in the manuscript, including the right to publish, are reserved to the IEEE History Center. No part of the manuscript may be quoted for publication without the written permission of the Director of IEEE History Center.  
This manuscript is being made available for research purposes only. All literary rights in the manuscript, including the right to publish, are reserved to the IEEE History Center. No part of the manuscript may be quoted for publication without the written permission of the Director of IEEE History Center.  


Request for permission to quote for publication should be addressed to the IEEE History Center Oral History Program, Rutgers - the State University, 39 Union Street, New Brunswick, NJ 08901-8538 USA. It should include identification of the specific passages to be quoted, anticipated use of the passages, and identification of the user. <br>It is recommended that this oral history be cited as follows:  
Request for permission to quote for publication should be addressed to the IEEE History Center Oral History Program, 39 Union Street, New Brunswick, NJ 08901-8538 USA. It should include identification of the specific passages to be quoted, anticipated use of the passages, and identification of the user. <br>It is recommended that this oral history be cited as follows:  


Lloyd Espenschied, an oral history conducted in 1973 by Julian Tebo and Frank Polkinghorn, IEEE History Center, Rutgers University, New Brunswick, NJ, USA.  
Lloyd Espenschied, an oral history conducted in 1973 by Julian Tebo and Frank Polkinghorn, IEEE History Center, New Brunswick, NJ, USA.  


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== Interview<br>  ==
== Interview<br>  ==

Revision as of 14:50, 19 May 2009

Espenschied.jpg
About Lloyd Espenschied

In many ways, Espenschied's career epitomizes the pioneering spirit of the early days of wireless. As a high school boy in Brooklyn in 1904, he became so captivated by radio and vacuum tubes, he found himself unable to open his textbooks. By 1907 he had become a self-taught operator, conducting experiments in a shop he set up in his grandfather's attic, and spending most of his time at the Brooklyn Children's Museum. His school work completely neglected, Espenschied left school in 1907 and went to sea as a wireless telegraph operator. Three years later he found himself in the office of AT&T's chief engineer, John Carty, with little more to recommend him than a note of introduction. Within days, Espenschied found himself working for AT&T designing loading coils — a job he knew nothing about. Within a few short years, Espenschied went on to invent a new kind of loading coil. By 1915, he was involved in high-frequency wire transmission and wireless telephony. Early experiments and demonstrations found Espenschied climbing 160 foot frozen antennas in the ice-glazed hills of Montauk Point, stringing antenna between a water tank and a smokestack in the Hawaiian wildnerness, and building experimental coastal stations on the Jersey shore for short-wave trans-Atlantic telephony. Espenschied's work in the development of commercial equipment for long lines eventually led to the development of coaxial cable. A charter member of both the Wireless Institute and IRE, Espenschied received over 130 patents during his career and was awarded, among other honors the Television Broadcasters Association medal and the IRE Medal of Honor.

In the interview, Espenschied provides a lively and colorful description of his work for AT&T in the early twentieth century. He discusses the transition period in wireless telegraphy from spark to continuous wave transmission, and various developments in the application of gaseous and vacuum tubes in high-frequency transmission. Espenschied offers a glimpse into the experimental work leading to the establishment of a transcontinental line in 1915. The interview continues with a discussion of Espenschied's work leading to the development of coaxial cable and trans-Atlantic commercial and radio telephony. Also included are a discussion of the role of amateurs in the early days of radio, Espenschied's development of various crystal filters, and his patent on the use of reflective waves on railroad rails.


About the Interview

Lloyd Espenschied: An Interview Conducted by Julian Tebo and Frank Polkinghorn, IEEE History Center, June 2, 1973

Interview # 011 for the IEEE History Center, The Institute of Electrical and Electronics Engineers, Inc.

Copyright Statement

This manuscript is being made available for research purposes only. All literary rights in the manuscript, including the right to publish, are reserved to the IEEE History Center. No part of the manuscript may be quoted for publication without the written permission of the Director of IEEE History Center.

Request for permission to quote for publication should be addressed to the IEEE History Center Oral History Program, 39 Union Street, New Brunswick, NJ 08901-8538 USA. It should include identification of the specific passages to be quoted, anticipated use of the passages, and identification of the user.
It is recommended that this oral history be cited as follows:

Lloyd Espenschied, an oral history conducted in 1973 by Julian Tebo and Frank Polkinghorn, IEEE History Center, New Brunswick, NJ, USA.


Interview

Interview: Lloyd Espenschied
Interviewed by: Julian Tebo and Frank Polkinghorn
Date: June 2, 1973

Early Life

Polkinghorn:

We would like to talk to you a little bit about your recollections of the early days of radio and the American Telephone and Telegraph Company. You moved to Brooklyn as a young boy, I believe?

Espenschied:

Yes. A lad of twelve, I think, which was about 1901.

Polkinghorn:

Then you went to grammar school and high school in Brooklyn and started as a radio amateur about 1905?

Espenschied:

That's right.

Polkinghorn:

Why don't you tell us a little something about that?

Espenschied:

I will start about 1904, when I was at Boys' High School in Brooklyn. That was when Brooklyn grew more than a tree, before it became submerged in the agrarian element. The Boys' High School was high academically and in broad appeal. An out-of-course activity was the so-called electrical club. That club was permitted to use the apparatus in the physics lecture room and was headed by Dr. Hale. This physics room had in it the devices that fired my imagination such that I never got over it. Then and there I became an advocate of electricity in general and vacuum tubes in particular--and radio also starting in about 1904. In the apparatus cabinet were these kinds of vacuum tubes, flasher tubes, perhaps a half dozen of them, severed thorns that light up brilliantly, Cookes tubes that had no color in them, Hipthorbs tubes they should have been called, and X-ray tubes. These tubes are driven by a Rumford coil, a fat black cylinder mounted on a mahogany case with an interruptor on the end of it, and a ten-inch spark coil, the kind that the Marconi Company used for transmitting sets on ships. This apparatus fired my imagination such that I never got over it, especially when the boys brought in some of their own apparatus. Thereafter, I couldn't study what was prescribed for me in school. My marks were poor. I kept right at it in my grandfather's attic, where I started a shop. By 1907 I was a self-trained operator, an amateur experimenter, one of a group of boys centering around the Children's Museum in Brooklyn. In my last year of high school I was fearful I wouldn't pass my examinations, so I dropped out before June and went to sea as a wireless telegraph operator in 1907.

That same year, in May, several of us had gone to a lecture that Lee De Forest had given on wireless at the Brooklyn Institute of Arts and Sciences. In this lecture, he passed around a queer little tube to all the audience. It was the first three-element tube to be shown in public, I found out afterwards. He passed this around and everybody looked at it and said, "So what!" Even De Forest said that he didn't know what it was all about. He looked on it as a detector. Actually it was an evolution of the Fleming valve, but he would never give credit to anyone. By the fall of 1907 I had realized that I needed more schooling, went back to a private institute, and graduated in 1909. My first job was with the Telefunken Wireless Telegraph Company, supplying German apparatus to the U.S. Navy and Army. They were the best apparatus then available anywhere. But I soon found that I either had to be a German and go to Germany and take a course there or else get out. So I got out and looked around, and the next thing I knew I was in the office of the chief engineer of the AT&T company, John J. Carty. This was 1910. I had secured a note of introduction and Carty invited me and talked with me. He summoned one of his assistants, F.B. Jewett, and within a few days I was with the AT&T Company, just like that. That's the way it went in those days.

AT&T: Loading Coils, Wireless

Polkinghorn:

What did you do when you first went there?

Espenschied:

Well, Carty said, "Lloyd, we don't have any laboratories. We might have later on, but we don't now. How would you like to work on coil design, loading coils and things like that?" That sounded interesting, but I didn't know anything about it. They assigned me as an assistant to Thomas Shaw. To design loading coil. I picked it up rather rapidly, and within a couple of years I was inventor of a new kind of loading coil. At the same time I was supposed to follow wireless development outside the company, to keep the company informed of what was going on.

Polkinghorn:

This was a definite assignment to watch the developments in radio in anticipation of what AT&T might do.

Von Lieben Tubes

Espenschied:

Yes, that's right. I often thought afterwards that to my boss, Thomas Shaw, it must have been frustrating to have an assistant who wasn't always working for him, who was throwing off the handle on his wireless business. But that paid off in time. In 1912 there appeared in the English literature a reference to a new kind of a German device, which proved to be the von Lieben vacuum tube used as an amplifier and as an oscillator. This was the fall of 1912. By that time I had come under the tuition of John Mills. I called this to his attention, and he immediately drafted a letter to the European chief engineer in Antwerp, a member of the Western Electric Company at that time, asking him to investigate and report, which he did within a few months' time. Von Lieben was an Austrian, then working in Germany.

Polkinghorn:

What was the difference between the von Lieben tube and what De Forest had?

Espenschied:

The von Lieben tube at that time was a gaseous device.

Polkinghorn:

So was the audion, wasn't it?

Espenschied:

Yes, the audion was also a gaseous device, but it soon came under the control of AT&T and became a vacuum device.

Captain Squire's Wireless Device

Polkinghorn:

Did AT&T take the von Lieben tube?

Espenschied:

No. We got onto the trail of the von Lieben device just a little before the De Forest device was called to the company's attention. The company came to know the De Forest device through John Stone Stone, who had been a company employee in the old Boston days before that. John Stone Stone wrote a paper for the Franklin Institute hailing a new technique, high-frequency telephony. This is a year or two following the application of a wireless device by Squire, who later became General Squire in the Second World War. Back then he was Captain Squire. I knew Squire. I had met him when delivering German apparatus to the army. Squire had put up a lot of phony arguments, not supportable at all. He didn't have anything new, but he was a publicity hound. He got the newspapers interested and stirred up the company on it, and Drewitt was furious about it. Squire's paper on the subject was submitted to the AIEE, but was turned down by them. He had very little imagination. I must say, in discussing this paper, it doesn't read very well today. Ernst Rhumer, a Dane from Copenhagen, had everything that Squire had and then some. He wrote a book on the subject of wireless telephony, which was published around 1910, based upon the new kind of transmitter. This is the transition period between using sparks in wireless telegraphy to continuous waves.

Polkinghorn:

Yes, this was a transition between the ramped telegraph transmission and the continuous wave because you had to have continuous wave for voice.

Espenschied:

That's right. That began with the new transmission method. You can imagine how difficult it was to conceive of this little thing, the audion tube, becoming a transmitter. What was looked upon as a transmitter was a powerful device. This new one was an arc in hydrogen. This was 1912, going on into 1913. Well, John Stone Stone wrote this article on his old work, which was high-frequency telephony, for the Franklin Institute. He sent a copy of his article to Fisk in Boston, another copy to Carty in New York. This article was referred to a young MIT graduate taken on by AT&T, namely Harold Osborne, to report upon. Harold Osborne's report was decidedly negative. We couldn't get this high-frequency stuff around the loading coils. The company was all set up with loading and had been for several years. Loading was the thing for long-distance telephony. It took several years to get that out of our heads.

George Campbell, Michael Pupin Controversy

Polkinghorn:

There was a contest then between George Campbell at AT&T and Bell Labs' Michael Pupin.

Espenschied:

That had occurred back in 1904 or so, a little earlier than that.

Polkinghorn:

It was George Campbell and Michael Pupin both coming up with the same idea of loading.

Espenschied:

That's right. Campbell was the Bell man in Boston. He was the tutee of a professor in Columbia who had been studying network theories. Pupin learned what Campbell was up to. Then there's a problem in this line business. In order to put inductances in the line without reflection losses, you had to put these inductances in short intervals compared with the wavelength. That was what Campbell had appreciated and what he was doing, and experimentally he finally did it. In the meantime Pupin got wind of this problem and slapped in a patent application, which finally beat Campbell out. The company was so desirous of controlling this new development that they bought Pupin's before they knew the issue of the interference and practically dropped Campbell. Campbell was incensed about it to his very end.

Gaseous Repeater to Mercury Vapor Tube

Polkinghorn:

You had the Boymeeten tube and the De Forest audion that were, you might say, two potential sources of amplification. These were not considered as good as other forms of repeaters at first, is that right?

Espenschied:

Not as good as was necessary to be successful. Arnold had been taken on out of Milliken's laboratory to work on this very problem of a new kind of repeater. He chose to work on a gaseous repeater, which proved to be the wrong trail, but it was a logical thing to work on because the gaseous device could handle considerable power while a cathode ray tube device like the audion was small and weak in power. You wouldn't expect it to handle the power necessary for line work.

Polkinghorn:

The gaseous device that you say Arnold started work on, was that a mercury vapor type?

Espenschied:

Yes. Mercury vapor was Cooper Peter Hewitt's idea. He was the first, in this country, to advocate and do experimental work on the mercury vapor tube device.

Polkinghorn:

You were able to get amplification on the signals with the mercury vapor type tube?

Espenschied:

Yes, Arnold succeeded in doing that. He started in 1911, and by 1912 or 1913 he was getting some positive results. Unfortunately, the device proved to be inherently noisy and rather unstable, so it was never really hooked up --although it was later installed on the transcontinental line in 1915 just to compare it with the improved De Forest device.

Polkinghorn:

You had three things, Shreeve's mechanical repeater, the multivapor repeater, and the improved audion?

Espenschied:

That's right. That was improved in 1913 by Arnold. Arnold recognized what was needed and was able to get the gadgets out in 1913. From then on, electronics began to sparkle.

Polkinghorn:

Now to your part in that work. What did you do leading up to the opening of the transcontinental line in 1915?

Campbell's Wave Filter; Transatlantic Signal

Espenschied:

I did nothing on the vacuum tube per se, except I acted as a sort of an office boy and goader, asking why we don't do this and why we don't do that. Campbell in the meantime had invented the Campbell wave-filter and that intrigued me. I tried to get Campbell to explain the operation of the wave filter in physical terms, and it was quite impossible for him to do so. He would pull out his equations and show me them saying, "That's the reason: the phase changes here and that's what happens there."

Campbell was a first-rate scientist, but he was a big babe in the woods when it came to playing ball with anybody else. It was impossible. That's why he was never elevated in the company. He was pathetic really. Following the move of the company's engineering department from Boston to New York in 1907, Carty took Campbell on as an assistant, sort of a scientific wet-nurse, and he set him outside Carty's office. There he did his work, invented his wave filter and so on. The fellows working there with the AT&T company were not allowed to do any experimental work. They only did paperwork or went out to play on the line. If you're wondering why I never had much to do with the vacuum tube, it was because it was improved and went into service. By the beginning of 1914, there were rumblings about a young fellow up in Columbia who was receiving signals across the Atlantic. That was an unheard of feat at that time. This was Armstrong. I learned this and wrote a memo suggesting that we investigate it. In the meantime Pupin had communicated with Carty, I found, and the next thing I knew we were invited up to witness the reception by Armstrong over these unheard-of distances. I was taken along because I was an operator and could identify these signals. Sure enough, these were the stations across the Atlantic and across the continent.

Polkinghorn:

These were telegraph signals?

Espenschied:

Yes, telegraph signals. Both spark and continuous wave. Carty and his assistant could hardly believe their ears, what I was certifying to, that these signals came from such long distances. Armstrong had not revealed what he had in his boxes, but it was quickly apparent that it used a feedback audion.

Polkinghorn:

This was the beginning of the regenerative work?

Espenschied:

Yes. This was early 1914. In the meantime, Fritz Lowenstein, here in New York, had early in 1911 made De Forest's audion into an amplifier before De Forest ever did, and also made it into an oscillator and used it to transmit speech. This was in his laboratories in Nassau St. in New York.

Patent Controversy over Hard VacuumTube

Polkinghorn:

Did Lowenstein have a hard vacuum tube?

Espenschied:

He used a soft audion tube.

Polkinghorn:

So Arnold is really the one who gets the credit for developing a hard vacuum tube out of the soft audion.

Espenschied:

About the same time, similar work was done by Langmuir at the General Electric Company. It resulted in a long patent interference between Arnold and Langmuir. Arnold did not file a patent application on his hard tube. When it was learned that General Electric had filed a patent on the same thing, then the company turned around and filed a patent before Arnold did and came into interference with Langmuir. This interference went on for many years.

Polkinghorn:

It went all the way to the Supreme Court, as I understand it.

Espenschied:

That's right, it did.

Polkinghorn:

As I understand, the Supreme Court said there was no patent because it was a natural thing -- there was no patentability, but if there had been patentability Arnold would have been the one patented.

Espenschied:

That is right. A complete vindication of Arnold

Experiments with Vacuum Tubes, Radio

Polkinghorn:

About that time, studies were being made on transmission between Arlington, Virginia (the Navy Station) and Europe and also to Hawaii.

Espenschied:

A year or two later. The significant thing about 1914 was that we began to experiment with the high-vacuum tube as an oscillator and a transmitter for carrier-current work. High-frequency wire transmission. To explore that situation, one of our new recruits, Raymond Heising, taken on in 1914, was put to work to see what could be done with the vacuum tube as a transmitter, a receiver, and selective circuits for high-frequency transmission over wires. This was the beginning of our carrier work. Heising carried out that work, which was very promising, just using breadboard models in our laboratory. By that time it became apparent that with higher power tubes we could apply the same technique to wireless telephony.

The scene then shifted, beginning in 1915, to experiment in radio telephony using the high-vacuum tube as a power tube device for transmitting, as well of course as the other vacuum tubes for receiving. I began to take part in that work. I left AT&T and went out to Montauk Point, where I took charge of the building of a small station house. The first radio telephone station was the Bell System, which was experimental only. I also went down the coast as far as Virginia, looking for a receiving site to go with this transmitting site at Montauk. We wanted to transmit over water because this was long-wave ground transmission, you might say. That experiment succeeded in April. I remember well, it was Easter Sunday, 1915. The delegation of brass hats showed up in Montauk Point from New York to witness the first transmission of speech by wireless with the Bell System, headed by John J. Carty. With him was Professor Milliken and the rest of them. On the morning that this experiment was to take place, the whole place was a mass of snow and ice, the hills of Montauk were glazed with snow and ice. We were supposed to start up with the machinery, but when we got out to the station from the little hotel, the antenna was down. The shaft supporting the antenna had frozen and the tension had broken it. I climbed one of the towers. These were steel towers, put up by a contractor.

Polkinghorn:

How high were they?

Espenschied:

160 feet.

Polkinghorn:

You went all the way up there?

Overseas Transmissions

Espenschied:

Yes, I went up one and a New York Telephone Company man went up the other one. We got the darn thing working within a few hours. Sure enough, the experiment was a success. These brass hat boys talked from there to Wilmington, Deleware, where they were on the top of the DuPont Building. I had chosen that place as a likely candidate, without knowing that the elevators in the building would raise havoc with the reception because of the sparking of the contacts. Anyway, the reception was good and I could talk back by wire and that Sunday ended happily, fortunately.

Then we had to do something better than that, so Carty decided that he was going to try to bridge the oceans, just like that. The only tubes we had were these little power tubes of about ten watts each. I supposed we had 100 watts at the most. But the prospect was that we could build bigger tubes, so Arnold and the tube shop got busy to produce bigger and better tubes. Three or four men were dispatched to various places, Paris, Canal Zone, Mill Island, California and Hawaii to do the receiving. The Navy promised to cooperate, to let us install a new powerful transmitter that we were going to build at the foot of the towers at Arlington. John Mills made the arrangements there. Later on, Heising took his tube racks, hundreds of these fifty-watt tubes, down there and tried to make them work in parallel.

Polkinghorn:

What sort of antenna were you using?

Espenschied:

The reason we were going to Arlington was to use the big Navy antenna. This was long-wave stuff, 5,000 meters or so, at 60 kilocycles. I left for Hawaii on May Day I think.

Polkinghorn:

At that time Shreeve was over in Paris, is that right?

Espenschied:

Shreeve and Curtis went to Paris, yes. Carty told me before I left that he had put my name down to go to Paris, but we were doing this in cooperation with the Navy, and when the Navy people saw my name they realized that with the war going on in Europe, I would never get to first base in Paris! So he said, "You go the other direction, you go to Hawaii. You won't be able to receive anything as far away as that, but go see anyway."

Polkinghorn:

So you had a year of the singles in Hawaii. Was this voice transmission?

Espenschied:

Yes. All summer long I stayed there sampling the air, listening to the radio stations around the world, and waiting for the others to get up enough power to reach that distance. By the fall, the conditions were so good that we could get through to them, and by October I was receiving practically everything that was transmitted at certain hours of the day. You couldn't receive at all hours of the day, only a few hours of the day out there.

Polkinghorn:

The antenna was non-directional, it was just spread out east and west, north and south.

Espenschied:

It was really broadcast.

Polkinghorn:

As were almost all other stations at that time.

Espenschied:

I suppose so.

Polkinghorn:

I believe that Shreeve and Curtis were limited in the time that they could use the Eiffel Tower.

Espenschied:

Yes, very limited. They never did get very good reception there. In fact, they didn't need the Eiffel Tower, as it turned out. When I went to Hawaii I was told to go to the Naval Station there, which is in the harbor of Honolulu. I did and found that it had a lot of interference, it was no good. I went and erected my own antenna out in Pearl Harbor, which was then a wilderness, only a power station, an officer's building, and a storage building on the docks. I ran this antenna between a water tank and smokestack, then down into an old carpenter's shop where I did the receiving, thanks to B.W. Kendal's homodyne reception, which was invented then and there. Homodyne reception means that the detecting oscillator was oscillating in unison with the received carrier. It had to be in exact unison, and the control was so exact that I couldn't move my body after setting it properly. I had to stay perfectly still and then receive it. The reception was really good -- so good that when I demonstrated it to the commandant, after listening to a speech he asked, "Where did you say this was from?" So I said, "Washington." I could see he didn't believe it. The following day his aide Lieutenant Lando, came over and started to search out all the wiring in my little place. He explained to me, "The old man wanted to me check up all the wiring here, to make sure that it doesn't come from the PBX next door, the Private Branch Exchange."

But when the press release occurred in New York following the success of the experiment, the Navy was only too glad to claim it. So from the first announcements in Hawaii, you would think it was the Navy that did it. That was alright -- we didn't mind. They played ball with us. That was 1915. Rather than have everybody think they were going to have a telephone service across the ocean right then and there, the whole thing was played down. The telephone company was fearful of public expectations. We knew very well that we couldn't give the service for years to come. Soon after that, when we got into the war, all wireless was blacked out for the time being until about 1919. But there was still a lot of experimental work, and manufacturing of sets for the military. I was not involved with that.

Long Lines and Concept of Coaxial Cable

Espenschied:

What I was involved with was the development of commercial equipment for long lines, which began in 1916. I was put in charge of the long lines and of the transpositions and means for reducing cross-talk. Experimental work we carried out in the Midwest at first. After that a new man from MIT, named Herman Affel, was put in my group. He headed up the carrier work on the line end of it. The troubles we got into there finally led to the coaxial cable conception because the induction between these open wire lines was such that for frequencies higher than about thirty kilocycles it was impossible to duplex it, to use the same channels over again on successive lines without their interfering with each other. That went on for several years. We made studies of transposition, increasing the transposition to the open wire lines and all kinds of crafty things, but to no avail -- the open wires were in such trouble both from cross-talk within our own system and from interference from radio stations outside that were using the same frequencies we were using.

Polkinghorn:

If you were using thirty kilocycles, then you were getting into the long-wave radio range?

Espenschied:

Yes, that's right and we suffered from that interference. So we were beside ourselves on what to do. I began to think, "We'd better put a shield around these wires and you can't put a shield around a whole pole line, what will we do? So, we'll put a pair of wires in a pipe." We began monkeying with that idea and then wondered, "Why two wires?" So we tried just one wire in the pipe and then shrunk the pipe down a little. Sure enough, we started to experiment then with the pipes. This was in Phoenixville, Pennsylvania. That was with a pipe about 2 or 3 inches in diameter. Then radio technique came into use for detecting and amplifying, which was really necessary because we were going up to even higher frequencies. The next step was to put it in the laboratories to develop it in cable form. Schriebey came into the picture then. He was transferred from AT&T to Bell Laboratories in the late 1920s.

Radio Broadcasting

By that time broadcasting had been born, and that became the biggest thing in radio, starting around 1920. Upon the conclusion of World War I Ma Bell started looking around at what to do with its radio experience. They decided to develop connections to ships, extending the land line to ships at sea. That was a project that took us down the Jersey coast to Deal Beach. Building these coastal stations we found amateurs inland were responding, writing "Send us some more, what is your schedule going to be?" Before we knew it, we were catering to the amateurs. Word of this got to J. Carty and he thought it was quite undignified, especially since by that time we had an agreement with the GE Company to give them the freedom of supplying the equipment to the amateurs. So these experiments from Deal Beach and also from New York City, which were reaching out and getting responses from the amateurs, were called off, much to the chagrin of our engineers who were following their own noses in the true pioneering spirit.

Polkinghorn:

What you were doing was making use of the amateurs to determine the effectiveness of the short-wave transmission?

Espenschied:

That's right.

Tebo:

You say short-wave transmission, so your transmissions through Deal were in the middle of what's now broadcast bands?

Espenschied:

When I say short-wave, I'm comparing it with the 2500- and 5000-meter work that had been done before.

Tebo:

We have to back up a little bit. Tell us about the start of the long-wave work in about 1920 or 1921.

Espenschied:

What led us into that was that we negotiated an exchange of patent rights with the General Electric Company, which was also forming the RCA at that time--Radio Corporation of America. RCA built a big station out in Rocky Point, and Alexanderson of the General Electric Company had been supplying alternators, high-powered, long-wave alternators for trans-Atlantic wireless calligraphy for the RCA. Another station was being built down in New Brunswick. This was a renewal of the trans-Atlantic picture and rather than being left without telephony in it, Ma Bell jumped in and said, "We want to undertake trans-Atlantic telephony". We arranged with the RCA people to permit us to put our transmitter in their station at Rocky Point, and use one of their long-wave antennas to transmit to Europe.

Polkinghorn:

What wavelength was that? Was that up around 2500 meters?

Espenschied:

More than that -- 5000 or 6000 meters.

Tebo:

The reason that you got that antenna from RCA, as I recall, was because about this time RCA was becoming interested in what we now call "high frequency." Their plan to build an extremely large station with lots of antennas fell through at that time, isn't that correct?

Espenschied:

I think that's so. The short-wave station didn't come along until a little after that?

Polkinghorn:

The amateurs were in the short waves about 1921, and I think RCA followed very soon after that.

Espenschied:

Yes, I think that's right.

Polkinghorn:

Soon after you made arrangements with them, I believe, the antenna was free because they really didn't want to use it. They would rather go to high frequencies. They didn't build their South American antenna as they intended either.

Espenschied:

We got the use of this antenna, and we undertook to study the transmission across the Atlantic, which meant many hours, many seasons, observing the effect of sunlight and weather in general on the transmission path. We sent a party to England with Friis and some others who did the receiving over there on the British side. The first reception was done in Britain on this schedule, and this studying went on for several years. In the meantime, short wave piped up and began taking front stage. Bell System went to short waves also.

Polkinghorn:

I have forgotten the exact details, but the short-wave work occurred just about the time that Bell Laboratories was formed in 1925, perhaps a little earlier. AT&T decided to go ahead with that, and see what kind of a competitor it was for the long waves. That's about the time I came into the picture.

Espenschied:

About that same time in 1925, I was in Paris attending an international conference, when I learned with chagrin that AT&T had sold all of its foreign properties to ITT. We felt that it had been sold out from under us, but I guess it was a pretty good policy for AT&T to let loose its foreign business, which was already big and vulnerable to attack.

Polkinghorn:

The commercial and radio telephony across the Atlantic, did that begin in 1925?

Tebo:

Yes, the long-wave circuit opened up, I believe, in 1925. Lloyd knows this better than I do. Let him tell his story.

Espenschied:

No, I think it was a little later than that, 1926 or 1927.

Tebo:

As I recall it, they delayed opening the long-wave station until just after we were really running the short-wave station. There was just months' difference between the two, as I recall.

Espenschied:

Yes, we were working upon the short wave as a support for the long wave. Of course, the short wave began taking the lead. This brings us up to around 1930.

Reflexive Waves on Railroad Rails

Polkinghorn:

About that time you got the idea of making use of reflective waves on railroad rails?

Espenschied:

Yes, I got that idea as early as 1918. I filed the patent application on the use of reflective waves as a railroad safety device, shooting waves along the track. I filed patents personally. The company was not interested in that sort of thing.

Polkinghorn:

You got patents in England and Germany, as well as the United States.

Espenschied:

Yes, I did.

Polkinghorn:

On your own?

Espenschied:

On my own, and it took me some years to pay off my patent attorney! It was a very foolish move on my part because I found that the railway signal people were not interested in that kind of thing. There was no market for it. When the air mail started going, these planes needed protection against hitting mountains. I began to think of the same principle that's applied to airplanes.

Polkinghorn:

The signals on railroad rails as a safety feature is the same idea of reflected signals from airplane to ground to give you the terrain clearance?

Espenschied:

Yes. Measuring the time interval recorded to receive the reflected wave. I found that although my conception dates were earlier than anyone else's, I was so slow in filing patent applications, not having the means to pay a patent attorney, that I did not receive all the claims that I had expected. But I claimed enough so that I did think about it. The company was not interested in it at all at first, but finally United Airlines went to Western Electric, the supplier of their apparatus, and they bought it and asked Western Electric to develop it. That way my patent came into play.

Polkinghorn:

In fact, that is really the fundamental principle in radar.

Espenschied:

I remember very keenly because the first patent that I applied for, the railway signal using a reflected wave, was turned down by the patent office on the basis that there was no such thing as a reflected wave in ordinary electricity.

I had to go pick textbooks to counteract this negative attitude. The patent examiner just didn't know. I remember very keenly the disappointment in that respect.

Patent on Coaxial Cable

Polkinghorn:

About that same time you got the patent on the coaxial cable, so you spent quite a bit of time on high-frequency transmission on cables, but you still were a staunch advocate of going into higher and higher frequencies both on conductors and also in radio.

Espenschied:

Yes, and I see that frequencies are extremely high now. The dielectric thread transmission lines -- light transmission over filaments of glass fiber.

Transoceanic Cables

Tebo:

We haven't said a thing about the trans-oceanic cables. Do you want to say something about that, Lloyd?

Espenschied:

Trans-oceanic cables. I did not work on that. That came along naturally enough by the evolution of the electric tube amplifier.

Tebo:

Just to make the story complete here, that came off around 1930. They did quite a bit of work on it. But then they decided that it was economically infeasible at that time, and nothing was done on it for about another ten years. Then it was picked up again with the result that things developed to the point where we eventually got as far as telephone cables, and in the long run our radio systems were put out of use.

Espenschied:

The key to the success of the submarine cables, as I remember, was the perfection of the amplifier, using negative feedback, which enabled you to muliplex the operation.

Crystal Filters

Tebo:

About this trans-oceanic radio telephony that you were still concerned with, as I understand, you were involved in the development of crystal elements for filters. In other words, instead of sticking to the capacitor inductor type of filter, you developed a number of crystal filters, isn't that right?

Espenschied:

Yes and that crystal filter development grew out of the quartz crystal oscillator, first perfected for radio broadcasting, for stabilizing the frequencies of the transmitters. That came out of the work of Professor Cady at Wesleyan University.

Polkinghorn:

Didn't Warren Mason do a lot of work on determining the proper way of cutting the crystals?

Espenschied:

Lack did a lot of work on it first, and then Warren Mason.

Concept Anticipating Cable TV

Espenschied:

There is one thing I'd better mention in connection with broadcasting. When broadcasting started, I advocated doing it by wire as well as by radio. We actually did some development work with transmitting broadcasting by carrier over telephone lines and over power lines into homes. We actually built an apparatus and demonstrated it right here in New York City over the New York Edison lines and over our own lines in Manhattan. This was in 1925 or so.

Polkinghorn:

So, you were anticipating cable TV?

Espenschied:

That's right. I actually took out a patent broadly covering it, the point being to branch the circuit out through successive branching accompanied by amplification, to cover an area.

Polkinghorn:

This would enable you to avoid a lot of static and other interference?

Espenschied:

Yes, that's right. It also would enable you to offer the service as a service supported by the receiving public rather than by advertising at the sending end.

Tebo:

You might have been able to get away from the inane commercials!

Commercialization of Radio

Espenschied:

I feel ashamed of the part the company played in originating commercial radio in this country. I don't know how we could have done it otherwise, but it is a shame. Radio broadcasting degenerated into a regular signboard affair.

Polkinghorn:

Essentially, that's what TV has degenerated into as well.

Espenschied:

It is the same thing.

Tebo:

Lloyd, there is one thing I would like to get your impression of. My impression of the early days of radio, before I actually graduated and went into the business, was that most of the people that were in the business weren't really engineers at all. Most of them were amateurs, just building equipment without really designing. Have you anything you would like to say about that?

Espenschied:

Yes, that's probably true -- and of the early wireless companies as well. People would just build stuff and try it out and see what they could do with it.

Tebo:

If I had to name a few people, I think that John Stone Stone was ahead of his time for things like that, wasn't he?

Espenschied:

He was, so much so that he went broke.

Polkinghorn:

As I understand it, he was a stickler for precise frequency control, wasn't he? That is, to stay tuned right on the marks?

Espenschied:

Yes, precise selectivity and so on.

Tebo:

Then there was Pierce up at Harvard, who was, I think, ahead of his time.

Espenschied:

Yes.

Tebo:

Of course, our friend Fleming in England was way ahead of his time. He understood the relation between equipment and mathematics, probably better than anybody else at that particular time.

Espenschied:

And so did Zenic.

Tebo:

Yes, Zenic was good too. But most of the people, Lee De Forest for instance, had a doctor's degree, but I don't remember anything that he that did of a highly technical nature.

Espenschied:

No, he was no engineer. He was just a playboy all his life. He's just plain lucky that he stumbled into the three-element device. Just plain lucky. But that was handed to him for persevering; he kept at it, grabbing and grabbing at all the patent applications without knowing what he was doing.

Polkinghorn:

Almost getting into jail somehow.

Espenschied:

Almost, that's right. He should have been in jail! He was so guilty of malpractice.

Honors and Patents

Tebo:

I think it would be a mistake for us to end up an interview with you, Lloyd, without saying something about some of the honors that you have gotten. You got the best paper on research and development, as I recall. What was that for?

Espenschied:

I think it was one that Shreedy and I wrote.

Polkinghorn:

There was one in 1935, you were co-receiver of the AIEE Best Paper Award on Research and Development for the coaxial cable. In 1944, you got the Television Broadcasters Association medal for adapting the coaxial cable to wide bands for television.

Tebo:

You got the Medal of Honor of the IRE. What did you do for that?

Espenschied:

Nothing -- just being a good boy! I might say that I was a charter member not only of that but of the preceding society, the Wireless Institute.

Tebo:

You have over a 100 patents according to a Brochure in Engineering back about in 1940. How many did you actually get?

Espenschied:

I think it was about 130.

Polkinghorn:

Your case file shows 133 Bell System patents. Then you had a few on the outside.

Tebo:

Another place where I think you contributed materially was the CCIR meetings. I remember writing papers for you, with your instigation, saying that CCIR wants to know about this, let's give them a story. We'd write these up and you would take them over to Paris or some place. I have a feeling that some of those papers that you brought up at that time had a great deal to do with the standardization and understanding of radio all over the world.

Espenschied:

Well, some contributions. I attended many of those conferences starting with the National Hoover Conference in 1926, I think, and a conference of 1925 that I attended in Paris.

Polkinghorn:

We might point out that Lloyd's library of rare, early, electrical books is now in the Niels Bohr Library, at the American Institute of Physics, and most of his personal papers have gone to the Smithsonian at their request.

Tebo:

Yes, I would like to get that on record.

Polkinghorn:

He was a charter member also of the Institute of Aeronautical Sciences, charter member of the Downtown Athletic Club, charter member of The Oceanic Club of Forest Hills, has been active in the Boy Scouts around a year, and Vice-President of the Kew Gardens Civic Association back in 1949 to 1950. He has been active in other than technical areas.