March 1960 Popular Electronics
Table
of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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In 1960 when this article
appeared in Popular Electronics magazine, futurists were predicting
that within 10 years it would be possible to beam television signals between continents
and directly into homes. It was the eve of
Project Echo,
which boosted a 100-foot-diameter inflatable metallized plastic ball into low Earth
orbit to reflect signals efficiently back through the atmosphere. Engineers and
scientists were already planning the next best thing - a satellite that not only
reflected, but also amplified, possibly frequency converted, and would even steer
signals that impinge upon it. Envisioned in this article is hundreds of satellites
being available for relaying signals between all regions of the Earth on then-standard
VHF channels. We now have successful satellite television systems, but they operate
at Ku-band due to bandwidth requirements and need special converters to interface
with a television.Communications Satellites - Key to World-Wide
TV
By Ken Gilmore
Early this spring, a powerful rocket will roar into space and eject a strange
payload: a rumpled bundle of plastic that will within minutes puff itself into a
shining sphere one hundred feet in diameter. As this weird space balloon soars through
its orbit 1000 miles above the earth, thousands of radio signals will shoot skyward
from ground stations, ricochet from the satellite's polished surface, and dive back
to earth to be received thousands of miles from where they started. The experiment,
run by the U. S. National Aeronautics and Space Administration (NASA), will be known
as Project Echo.
Sooner than you think -- probably within ten years -- satellites
will make it possible for you to watch live TV programs from foreign countries.
Balloon satellites to be used in Project Echo are made of tough
plastic film coated with a thin layer of aluminum. Entire satellite, including the
firing container, weighs only 190 pounds. Balloon is inflated when sun's rays cause
water inside it to turn into steam.
A short time later - probably before summer - the U. S. Advanced Research Projects
Agency (ARPA), which directs our military space program, will hurl a different kind
of "talking satellite" into orbit. It will be much smaller than NASA's hundred-foot
sphere, and packed with complex electronic equipment. As it glides over one continent,
signals will flash from the earth to be received by the satellite and recorded on
tiny magnetic tape recorders. A few minutes later and half a world away, it will
play back the message to a ground listening station. This operation will be known
as Project Courier.
While Echo and Courier are the most comprehensive space communications projects
planned to date, they are not alone. At least one talking moon is already in orbit;
scores of others will soon be filling the air with electronic signals. Almost overnight,
sooner than anyone believes possible, the age of satellite communications will begin.
Space Timetable. Communications satellites will bring about profound changes
in our everyday lives. These pioneering accomplishments are coming soon:
• Before another year goes by, television signals will probably have been
transmitted back and forth across the Atlantic.
• By 1961, the Signal Corps will have enough Project Courier satellites in orbit
to form a regular communications system between our far-flung military outposts
around the globe. This system will be operational in 1961, not experimental.
• By early 1962, ARPA will have an electronic repeater satellite in orbit at
an altitude of slightly over 22,000 miles. Termed a "24-hour" repeater, it will
rotate at the same speed as the earth and will appear to hang over one spot on the
earth's surface - probably the mid-Atlantic. The thrust rocket designed to hurl
this five-ton moon into orbit is under construction.
• By 1962 or 1963, we will be watching live television from Europe.
• By 1970 - a short decade away - we will spin the dial and bring in hundreds
of stations from all over the world. Bullfights from Spain, exotic dances from the
South Seas, floor shows from Paris night spots - all will flood into our living
rooms through the magic of satellite video.
These are not just dreams. We have all the know-how and resources
needed to accomplish everyone of these projects right now. A crash program to get
the hardware into the sky has already started.
Operation of a "passive" satellite relay system - such as Project
Echo - is diagrammed below. While signals are being bounced off satellite 1, the
second antenna begins to track satellite 2, preparatory to switching from 1 to 2.
Scientists calculate that 25 such "sky-mirrors" in orbit would give world-wide coverage.
A "24·hour" active satellite repeater like the one at left designed
by Space Electronics would appear to hang suspended over one spot on the earth's
surface. This satellite is basically similar to the one to be launched in early
1962 by ARPA, but it is much smaller, measuring only six to eight feet long, and
weighing only 500 pounds. Solar cells would provide the power for relaying trans-Atlantic
television, telephone, and teletype signals.
Before 1980, there will probably be super communications satellites aloft, operated
by crews who commute back and forth from earth by rocket. The illustration on page
41 pictures one of these advanced satellites which is already being designed by
Radio Corporation of America.
Communicating with satellites. themselves is, of course, not new. (See "Telemetering
- Vital Link to the Stars," POPULAR ELECTRONICS, Nov., 1959.) Every satellite launched
by either the United States or Russia has maintained some kind of radio contact
with earth. But this contact has been used only to control the satellite or to report
on its operation to ground stations.
Now, we are beginning to use satellites as another link in our regular communications
networks. Employed as relay stations a thousand miles or more above the earth, they
will enable us to transmit radio, television, teletype, and other signals around
the world far better than we could do it any other way.
Early Experiments. The age of space communications was born
- by accident - in October, 1958. The scene was Cape Canaveral. As Pioneer I streaked
skyward, headed for outer space, the ground station signaled the rocket to fire
its next stage. But something went wrong. Repeated signals to fire somehow got channeled
into the missile's transmitter and were relayed to half the world before the space
vehicle destroyed itself.
A few months later, satellite communications of a more reliable type went into
operation with the launching of Project Score. The most publicized feat of Score
was the broadcasting of President Eisenhower's 1958 Christmas message to the world.
But it performed a series of more valuable experiments as well.
As Score circled the earth, Signal Corps engineers sent aloft radio and teletype
messages that were received and recorded by the satellite, then played back on command
to other stations thousands of miles away. When ground stations were within two
or three thousand miles of each other, the satellite relayed the message instantaneously,
without recording it first.
Communications in which the satellite is a passive element and acts as a mirror,
rather than as a relay station, have also been successful. The spent rocket case
that propelled Score into orbit was used by RCA for successful "bounce" communications
tests. In addition, signals have been bounced off the moon repeatedly in the last
few years.
The Necessity for Satellite Communications
Ultra-high-frequency signals - the kind used for television - travel only in
straight lines. They do not follow the curvature of the earth and therefore cannot
be picked up more than a few miles from the transmitter. Even the 1000-foot towers
now used by some television stations increase the maximum range to only a few hundred
miles. But a satellite, since it can "see" a large part of the earth, would give
vast coverage with u.h.f. signals.
Why must we use u.h.f.? Why not transmit TV by "short wave" - the kind used by
some radio communications? The answer: there simply isn't room. A voice signal uses
a very narrow channel, only a few thousand cycles wide. But television takes at
least five million cycles.
Even if we forget television, we still have a serious problem. The volume of
overseas communications has grown so rapidly that we are running out of channels.
International Telephone and Telegraph Company estimates that the message load will
be seven times as large in 1970 as it was in 1950. By 1963, all presently available
channels will be jammed to capacity. The only answer is more channels, and the only
ones still available are in the u.h.f. range. This means that satellite communications
systems must be developed quickly.
Civilian Projects. Although various systems could be used in
world-wide networks, most space experts feel the so-called "24-hour" active satellite
repeater, (the type scheduled to be launched by ARPA in early 1962) offers the greatest
promise. This advanced type may actually be the first to go into use for civilian
TV. There is even some chance that a civilian-built active satellite repeater will
be in orbit before ARPA's military version.
Dr. James C. Fletcher, president of Space Electronics, Inc., of Glendale, California,
says there is no reason why such a satellite could not be in operation within two
years. He estimates it would cost from $25,000,000 to $40,000,000. Dr. Henri G.
Busignies, president of International Telephone and Telegraph Laboratories, says
it might cost slightly more. But both men think it would pay its own way.
Forty or fifty million dollars may sound like a lot of money. But the recently
completed Atlantic cable cost $40,000,000, and can only handle about 50 telephone
conversations at one time. It cannot, under any circumstances, transmit a live television
program. The satellite proposed by Space Electronics would carry 250 telephone conversations
simultaneously - five times as many as the cable - or 125 telephone conversations
and one television signal.
Although enthusiasts like Dr. Fletcher are ready to begin, the project now -
efforts to round up financial backing are under way - other communications industry
leaders feel that since NASA plans to fire a 24-hour satellite repeater in 1962,
it would be better to wait and profit from this experiment. So the timetable for
the launching of a space outpost for civilian TV is uncertain.
Looking to the Future. Exactly how will satellite communications
affect our everyday lives? Imagine the year as being 1970 - just ten years away.
Hundreds of satellites of every nationality are now soaring through the skies, pouring
down torrents of information, entertainment, propaganda. You turn on the TV set
and bring in the BBC or Moscow just as clearly as you received home-town stations
back in 1960.
Since there are thousands of channels and since each has a potential audience
of billions of people, it has now become practical to televise programs of interest
to minorities - Greek drama, chess matches, lectures in differential calculus.
Asia and Africa have been flooded with inexpensive TV receivers, and Russian
and U. S. satellites are engaged in a fierce ideological battle for uncommitted
minds. (Long before the year 2000, the struggle to determine whether English or
Russian becomes the world's dominant language will have been won or lost on this
electronic battlefield.)
Mail is delivered anywhere on earth in less than a day. We write our letters
on a special form. At the post office, the words are transformed into electronic
signals which are transmitted via the mail satellite relay within a few millionths
of a second. A high-speed printer on the other end turns the signals back into words,
and the letter is delivered. The only delay is in getting it to and from the post
office.
By 1980, the changes will be even more dramatic. Newspapers will be produced
on demand in the home. All you will have to do is flip a switch on your facsimile
printer and out will roll the sports page, the funnies, the news section, or any
combination you select. You will have your own personal radio-telephone and you
will be able to call any place on earth at a moment's notice. Most business conducted
by personal contact back in 1960 will be handled over the video and facsimile channels
in 1980. Of course, your telephone will have already been equipped with a TV screen
for many years.
These wonders will begin to appear far earlier than most of us think. Everyone
of the devices described above is already in use. Not one new invention or development
will be needed to put any part of this system into operation.
Businesses all over the country, for example, now have their own facsimile systems
which transmit letters, pictures, and plans instantaneously from one plant or office
to another. Miniature radios which could be used in a world-wide paging system have
already been built. Complete engineering plans and specifications have been drawn
up for an intercontinental mail system using equipment which is already available.
The only new ingredient we need to make all of these miracles available is long-distance
satellite communications - and we will have it soon.
Profound Significance. The impact of global radio and TV will
be profound. It will mean not merely bigger and better entertainment, but it will
change our civilization. Arthur C. Clarke -- the internationally recognized space
expert - summed it up this way in an article in the September 1959 issue of Holiday
magazine:
"Soon, the great highway of the ether will be thrown open to the whole world,
and all men will become neighbors, whether they like it or not. Any form of censorship,
political or otherwise, would be impossible; to jam signals coming down from the
heavens is almost as difficult as blocking the light from the stars. The Russians
could do nothing to stop their people from seeing how Americans live; on the other
hand, Madison Avenue and blue-nose committees might be equally distressed - though
for different reasons - at a nation-wide switch to uninhibited telecasts from Montmartre.
"No one can ever anticipate the full significance of any major invention; did
Henry Ford dream that the very foundation of commerce, warfare, entertainment -
yes, and morality - would be shaken by the automobile? And what radio and TV have
done to our lives in the last decade merely hints at the revolution real telecommunications
will bring 20 or 30 years from now.
"How mankind will cope with the avalanche of information and entertainment about
to descend upon it from the skies, only the future can show."
One thing is sure, the sciences of rocketry and electronics have launched the
human race into the age of space communications, and there's no turning back!
Posted August 6, 2024 (updated from original post
on 11/20/2018)
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