ECHO - America's First Communications Satellite
By John R. Pierce
(c) SMEC // SMECC Reprinted from SMEC Vintage Electrics
Volume 2 #1
|"BALLOON SATELLITE ORBITS; DELAYED MESSAGE HERALDS NEW COMMUNICATIONS ERA"
said a page 1 headline of the New York Times of August 13, 1960, the morning after the Echo I communication satellite was launched. The heading of story by John W. Finney was, "PRESIDENT HEARD, His Talk Spans U. S.-Object Glitters in Sky Like a Star." In President Eisenhowerís recorded message, transmitted from a Jet Propulsion Laboratory antenna at Goldstone California to a Bell Laboratories ground station at Crawfordís Hill, New Jersey by reflection of a microwave signal from the 100 foot balloon satellite, he described the satellite as "one more significant step in the United States program of space research and exploration."
It was, and I had a good deal to do with it. This wasnít apparent from the New York Times story, which ascribed Echo to "the United States." However, in the story in the August 22 issue of Time, the Echo launch was ascribed to "the U.S. National Aeronautics and Space Administration", that is, NASA, and "Bell Telephoneís wispy (125 lbs.) Dr. Pierce" was identified as having persuaded them to do so.
This was true. My work on communication satellites brought me more public recognition than anything else that I have done. Perhaps it is a good point at which to start the story of my technical career.
Communication satellites are very important, as technological tools of communication. They have brought into our homes events from all parts of the world-Olympic Games, a coronation, a royal wedding. When the old dream of a journey to the moon was realized, something entirely new, communication satellites, sent pictures of the triumphant astronauts to all nations. Alas, satellites show us disasters, famines and wars in far lands, that have a worldwide impact because we see them.
In the sparsely settled part of Massachusetts where I am writing these words, a considerable number of homes have microwave dishes that point at the satellites which distribute TV programs around the country, and these dishes pick up tens of channels intended for broadcast and cable distribution. A few weeks ago I returned from a cruise on the Greek ship Illyria. The ship had a satellite terminal, and one could, and some did, use it to make calls back to the United States. A broker kept in touch with his firm; a mother with her children. I could go on almost endlessly about the impact of communication satellites.
Rather, I will say something about how a thing as important as satellite communication can come into being. It came into being rather indirectly, and without much overall planning. Indeed, careful planning almost killed satellite communication very near its start.
I came to work on satellite communication through my association with science fiction and fantasies about space. Iíd read science fiction stories in my teens, and perhaps before. When I was 20 and a student at Caltech (The California Institute of Technology), I wrote a science fiction story that took second place in a contest. I kept on writing, so that in all I have published 22 such stories, and 22 factual articles in science fiction magazines. I published the latter under the pseudonym J.J. Coupling in order to avoid the Bell Laboratories release procedures for technical articles, procedures that had nothing to do with the sort of things I wrote.
The main staples of early science fiction were robots and space travel. At the end of World War II, the V2 rocket, which the Germans used to bombard London, seemed to have brought space travel closer. Through being known as an engineer doing research at Bell Labs (Bell Telephone Laboratories, now AT&T Bell Laboratories) and a science fiction fan and author, I was asked to give lectures on space.
In those lectures I used photographs of the earth taken from V2 rockets that had been shipped to America after the end of the war. The substance of my talks was the sort of man-in-space romanticization common in science fiction magazines. Without authorization, I made and used colored slides of Chesley Bonestellís wonderful paintings of the planets. I discussed the effect of zero gravity on astronauts. The talks were fun, and audiences enjoyed them.
After 1954 I gave no more of these old-fashioned man-in-space talks. I was asked to give a space talk to the Princeton section of the IRE (the Institute of Radio Engineers, now incorporated in the Institute of Electrical and Electronics Engineers, the IEEE). I had a great respect for the IRE, and I felt that a science-fiction type of talk would be inappropriate. What could I speak of ? The idea of communication satellites came to me. I didnít think of this as my idea, it was just in the air. Somehow, I had missed Arthur Clarkeís paper on the use of manned synchronous satellites for communication.
In an article Donít Write, Telegraph, published in Astounding Science Fiction in 1952, I had calculated the power necessary to transmit signals between the earth and the moon, planets and stars. It was easy for me to calculate the power needed to send signals from one place on the surface of the earth to another by means of a communication satellite. I made calculations for large balloon-type satellites that would merely scatter the radio waves they intercepted so that about a billionth of a billionth of the microwave signal transmitted would be picked up by an antenna on earth. I also made calculations for active satellites with radio receivers, amplifiers and transmitters, both for satellites at low altitudes, and for satellites some 20,000 miles above the earthís surface, the sort of synchronous satellites we now have, which hang over one point.
I was amazed and delighted at the outcome of my calculations. By using currently available microwave equipment, any of these sorts of satellites could be used to communicate across oceans. The power required on active satellites was very small.
My lecture was well received, and Professor Martin Summerfield of Princeton suggested that I write it up and publish it in Jet Propulsion, the journal of the American Rocket Society. This I did, and Orbital Radio Relays appeared in the April, 1955 issue.
Alas, there was then no way to launch any of the satellites I had considered. Also, I was somewhat concerned with the reliability in space of the vacuum tubes and the primitive transistors of that day. I talked with a few people at Bell Labs about communication satellites, but nothing came of it then. On October 4, 1957 the Soviet Union launched Sputnik and startled the world. Recently, Cal Quate reminded me of a discussion of Sputnik among a small group of us at Bell Labs. He had asked me what my reaction to Sputnik was. I said, "Itís like a writer of detective stories going home and finding a body in his living room." For me, space had suddenly changed from science fiction to a technology that could be put to some sensible use. Not everyone saw it that way. For many, Sputnik heralded the realization of the old aspiration of science fiction-manned exploration of space. And, indeed, this old dream has been realized.
I was interested in communication satellites, but I couldnít put one up. That required persuasion. A dear friend of mine at Bell Laboratories, Rudi (Rudolf) Kompfner, the inventor of the traveling wave tube, became an advocate immediately. I set out to convince others.
The task was made easier by our finding that William J. OíSullivan of NASA had built, for another purpose, just the sort of metallized balloon that I had written about as one possible communication satellite, a passive sphere that would reflect part of a signal back to earth. Indeed, OíSullivanís balloon was of just the size I had considered 100 feet in diameter. OíSullivan had made the balloon because he wanted to measure the atmospheric density 1,000 miles above the earth through the drag on the balloon orbiting as a satellite. He hadnít been able to get NASA to launch it.
Rudi and I went to Langley Field and discussed the balloon, but not with OíSullivan, whom I never met. We used an ohmmeter to measure the conductivity of the aluminum coating on the plastic balloon, and decided that it would reflect almost all of the microwaves that struck it. We took samples of the aluminum coated mylar back to Bell Labs, and this proved to be true. Rudi and I set out to get someone to launch OíSullivanís balloon, both for his purpose and as a communication satellite.
Rudi and I wrote a paper that was published in the Proceedings of the IRE, in March, 1959. This paper lauded all satellites. Particularly, it published earth-coverage diagrams for satellites in orbits lower than synchronous orbit. I think that it was just after the publication of this paper that we learned of the paper Extra-Terrestrial Relays that Arthur C. Clarke published in the Wireless World in October of 1945. In that paper, Clark had pointed out that when manned synchronous space stations had been launched, they could be used for worldwide communication by radio. Thereafter we cited Clarkeís paper in everything we published.
Iím sure that we gave talks as well as publishing the paper. But, it wasnít easy to get anyone to launch a simple experimental satellite, such as OíSullivanís balloon. Most of those who heard of the idea of communication satellites wanted everything at once.
In October of 1958 I became a member of an ad hoc panel on satellite communication that was established to advise ARPA (Advanced Projects Research Agency, now DARPA, a part of the Department of Defense). This panel was briefed by military men who showed pictures of GI's with walkie talkies communicating by satellite.
The other members of the panel werenít that crazy, but the idea of a balloon satellite as a means of getting started was too much for them, or rather, too little. They wanted an operational military communication system immediately. By 1960 they had settled on a satellite called Advent. Advent was never completed. Had it been built, it would have been so heavy that no existing booster could have launched it. The Advent program was "reoriented" (abandoned and something else substituted) in 1962, after the expenditure of $170 million.
So, ARPA wasnít of any help to us in our effort to launch the satellite that finally became Echo.
In the summer of 1958, Rudi Kompfner participated in an Air Force summer study at Woods Hole in Massachusetts, a very pleasant place. He invited me up for a day, to talk about communication satellites, and particularly, about balloon satellites. The Air Force didnít help us, but the meeting was useful. William H. Pickering, the director of the Jet Propulsion Laboratory, which was soon to be transferred from the Army to NASA, was there. I had known him for many years. He was sympathetic with our idea, and agreed to supply a west-coast ground station if we could get the balloon launched.
This didnít mean that all difficulties were overcome. We had to convince the management of Bell Laboratories that launching an experimental communication satellite was a worthwhile idea. My boss, William O. Baker, the vice president in charge of research, seemed agreeable, and so did James B. Fisk, the executive vice president. But, Mervin Kelly was the president of Bell Labs. He called a luncheon meeting, probably in the latter part of 1958. His attitude was very negative. He asked an able mathematician to make a system study, which took some time and turned out to be very negative. Really, Kelly decided against the Echo idea right at the meeting. Rudi Kompfner thought that Echo was dead, but I just didnít hear what Kelly said.
Kelly was a great hero of mine, and a great leader of Bell Laboratories. Even great men can be wrong. Fortunately for Echo, Kelly retired early in 1959, Fisk became president, and opposition within Bell Laboratories turned to support. Early in 1959 NASA and Bell Laboratories somehow reached an agreement concerning Project Echo. Echo was to be NASAís project, and NASA would supply the balloon and would launch it. Bell Laboratories would build an east-coast ground station and NASA would lease it. The Jet Propulsion Laboratory, now a part of NASA, would build a west-coast terminal. Indeed, there is still an Echo antenna at JPLís Goldstone site, built for Project Echo but used since for other purposes.
It had been one thing to propose satellite communication, to make calculations concerning the feasibility of microwave communication by means of satellites, to locate OíSullivanís balloon, to stir up the enthusiasm of people at Bell Laboratories, JPL and NASA. It was something else to carry the project through. I wonít comment on how NASA and JPL did this, for I really donít know the details. They did their part well, except that the people at JPL seemed sometimes hardly to believe that when Bell Laboratories said that something would be ready at a specified time, it was.
At Bell Laboratories we had a wonderful resource for making an east-coast ground terminal. That was the Holmdel Laboratory. Not the new, big one, but the wooden laboratory that Harald Friis had made into a world center of microwave research. Harald had retired in 1958, and Rudi Kompfner was now head of the laboratory. Harald had brought wonderful people to work there. Because of Rudi and me and the technical value and attractiveness of the Echo experiment, these people were enthusiastic and eager to go ahead. Indeed, some preparation had been made before the agreement with NASA. At the end of 1958 Kompfner had used money available in the budget to order a lot of aluminum for a receiving antenna.
How was the work on Echo to be organized, how carried through? Some overall things Rudi and I decided, with the help of senior people at Holmdel. We were resolved that everything should be with the best available technology. We wanted the ground station to be what is now called "high tech", but we wanted to be sure that it would work when built.
I remember insisting on that the antenna should track the satellite from computed orbital data, so that the satellite could be tracked in the daytime and on cloudy nights as well as when it could be seen. Rudi and I wanted a receiver using the new maser low-noise amplifier, because this would cut down the amount of transmitter power to about a hundredth of that which would be needed if a conventional receiver were used. To make the maser effective, one needed a receiving antenna that wouldnít pick up the thermal radiation from the earth below when the antenna was pointed at the satellite above. A horn reflector antenna was chosen, the sort of cornucopia-shaped structure you can see on the tops of many telephone buildings that serve as microwave terminals, and on towers between such terminals. We chose for the FM receiver what is called "FM with feedback", an old invention that had seen no practical application. Because this sort of receiver tracks the large deviations in frequency of the FM signal, the bandwidth of the receiver can be comparatively small and the noise that the weak received signal must compete with is smaller than for conventional, broad-band FM receivers.
Such broad decisions were made rather early. How could the overall terminal, involving such features, be constructed and made operable in a timely and orderly way? People not at Holmdel, people not even in the research department, would be involved. Someone must keep everything in hand and in mind, must see that things got started and got done.
Bill Jakes (William C. Jakes, Jr.) was appointed project engineer. Organizationally, he reported to Art Crawford (Arthur C. Crawford). Crawford reported to Kompfner and to C. Chapin Cutler ( the director and assistant director of radio and electronics research), and Kompfner reported to me. But, to everyone concerned with the Echo project, Jakesís word was final law. He had the full support of Cutler, and everyone up the organizational line. That didnít mean that we didnít talk with Jakes. He talked with us and with many others. But, it was up to Jakes to arrive at final work assignments and timetables. He was wonderful at this. His subsequent career showed him to be an ideal project engineer, hard working, ingenious in overcoming obstacles, extremely well organized, and universally liked by those who worked with him.
I remember that in the early days of his role as project engineer, Jakes commiserated with me on my not having the fun of running the Echo project myself. I donít know what I said, but it certainly wasnít the full truth-that the Echo ground terminal would never have got built or worked had I been project engineer. Through a mixture of ineptitude and boredom, I would have flubbed. There may be people of universal capability, though I havenít met any. Mostly, the talents of talented people are very different. It is of great importance that people undertake what they can do and like to do.
A lot of time passed between the initiation of the Echo project at Bell Laboratories and the successful launch on August 12, 1960, and much was done.
The Crawford after whom the hill is named has no connection with Art Crawford, who designed and had constructed the wonderful horn reflector with which signals from Echo were first received. Crawford was a fine microwave engineer and researcher. He was also an excellent mechanical designer. The antenna was built in the Holmdel shop.
This antenna, which had an aperture approximately 20 feet square, was of considerable size and complexity. The horn antenna rotated around its long axis to point in elevation, with a cab at the small end of the horn to house the maser and other receiving equipment. The whole structure rotated on a circular track to point in azimuth. So good was the mechanical design that a man could easily move the antenna on its track, though, of course, an electric motor of moderate size was used in pointing it. This was the antenna made doubly famous when Penzias and Wilson later used it in the discovery of a cosmic background radiation of approximately 3 Kelvins, a remnant of the big bang of creation, a discovery for which they were awarded a Nobel prize.
I contributed a little to the course that the ground station took after the initial decisions that I have mentioned. At one point Roy Tillotson was concerned with the cost of buying a 60-foot transmitting antenna for around $200,000. I told him to go ahead, provided that he would promise to throw it away when the project was over. Substantial investments in equipment sometimes inhibit researchers from turning to new fields.
Mostly, during the days in which Echo was in progress I turned my thoughts to active communication satellites, as did Rudi Kompfner and Roy Tillotson. Roy sketched a satellite much like Telstar in a memorandum of August 24, 1959.
I was considerably concerned with gravity-gradient attitude control, which I had mentioned in my 1955 paper, as a means for pointing a satellite at the earth. Several mathematicians at Bell Labs picked this idea up, notably, Sam Morgan. Indeed, he made a very early computer-generated animated film showing a satellite settling down in attitude. Alas, gravity-gradient attitude control, while effective for low-altitude satellites, is useless for synchronous satellites, with which the future of satellite communication proved to lie.
Both Rudi Kompfner and I became spectators of the excellent progress of the Echo terminal at Crawford Hill. We were gratified when signals were bounced off the moon in November 1969. Signals were bounced off the small Tiros satellite on May 11 and July 29 1960. There were suborbital "Shotput" launches of Echo balloons on January 16 and February 27 of 1960, and signals were bounced off the balloons so launched. I was disappointed when the first attempted launch of Echo failed on Friday the 13th of May, 1960. Happily, the Echo satellite was launched successfully on August 12, 1960.
Both Rudi Kompfner and I were so far from participation in the technical details of the work that we were sent from the operating area of the terminal to another small building, equipped only with a loudspeaker over which we could hear any received signals. There we heard President Eisenhowerís recorded message so clearly and noiselessly that we at first thought that it was a local transmission from Crawford Hill to the JPL station at Goldstone. Then a fault of pointing caused a momentary interruption of transmission, and we realized that we had been listening to a signals transmitted via satellite from Goldstone to Crawford Hill.
My dream had been realized. Of course I was gratified, but I donít remember much about events immediately after launching Echo. I must have been interviewed, by phone or in person, for I did say, in contrasting communication satellites with man in space, which was all the rage then, that I had been listening to a different drummer. Time quoted this, giving the appropriate extract from Thoreauís Walden- "If a man does not keep pace with his companions, perhaps it is because he hears a different drummer. Let him step to the music which he hears, however measured or far away." This I had done, explaining my view in articles entitled Spacious Fantasies in the Transactions of PGMIL in January 1960 and Letís be Practical About Space in Space World in May, 1960.
One thing that I do remember vividly about the period immediately after the launch of Echo is a visit to Crawford Hill by T. Keith Glennan, then Administrator of NASA, and several members of the Federal Communication Commission. Glennan is a delightful man, whom I encountered in various roles (always leading) in the following years. When I last saw him we had a sort of fond farewell lunch together at the Aerospace Corporation. We were both Trustees. He was retiring at age 70; I still had a few years to go.
On that day at Crawford Hill in 1960, we transmitted a photograph of the group by wire to a Naval Research Laboratory terminal at Stump Neck, Maryland, whence it was transmitted back to Crawford Hill via Echo. A framed copy of the photo received stands on my bookcase.
Glennan expressed admiration and a little surprise that everything had worked perfectly. I wasnít surprised. I knew the capabilities of Bell Labs people, and the care which they took in what they were responsible for.
For several years, longer than expected, Echo continued to cross the sky and attract attention. Bill Jakes kept careful track of its orbit. Small notices appeared in daily papers telling where and when to look for Echo. I looked at Echo a few times but not often. After the launch of Echo, and even before, my mind had turned to something beyond it-an active communication satellite.
John R. Pierce was born in Des Moines Iowa, March 27, 1910.
He graduated high school in Long Beach Calif. in 1929, after which he attended Cal-Tech where he received his B.S. in 1933, his M.S. in 1934, and Ph.D. in 1936.
John Pierce worked at Bell Telephone Laboratories for 35 years, during which time he was involved in design work on a large number of communications systems including Echo and Telstar. He retired in 1971.
During this time John Pierce had an active interest in authoring science fiction articles for many of the popular magazines of the day. None of the articles were in his name though, he used the pen name of John Roberts and J.J. Coupling.
Now a Professor of Music Emeritus at the Center For Computer Research In Music And Acoustics at Stanford University in California.
His recent book, co-authored with Michael Noll, Signals the Science of Telecommunications, is available from The Scientific American