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June 1945 Radio-Craft
 [Table of Contents]
Wax nostalgic about and learn from the history of early electronics.
See articles from Radio-Craft,
published 1929 - 1953. All copyrights are hereby acknowledged.
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You might think that being concerned
about the inefficiency of traditional Edison type incandescent light bulbs is a
recent thing. However, as this 1945 Radio-Craft magazine editorial by Hugo
Gernsback points out, it was known early on that only about 10% of the energy consumed
by those bulbs actually create light while the rest is dissipated as heat. The difference
is that at the time, the "science" was telling us we were headed for a new Ice Age,
whereas nowadays the same science is telling us we're headed for planetary death
by Global Warming. He postulates a world that will someday be powered by the conversion
of solar energy to electricity, and also predicts communications via visible light
rather than radio waves. Vacuum tubes would operate at and emit visible light signals
to eliminate cables. Of course during the daytime the ambient light from the sun
would be a problem to be reckoned with. Surprisingly, Mr. Gernsback, for all
his amply demonstrated ability to predict the future and suggest devices and methods
to accomplish those goals, did not prior to the announcement of the transistor's
invention discuss much about the role of semiconductors in future electronics.
See The
Radiolight "Talking Beam," April 1933 Radio-Craft.
Editorial: Radio-Light
 ... We are still at the very beginning of
the radio and electronic arts. The greatest and undreamt of applications lie as
yet in the future. There is still much unknown territory in the electromagnetic
spectrum which holds out great promise ...
Hugo Gernsback
Every time you turn on an electric light of the filament type, over 90% of the
electrical energy goes to waste in heat, which you do not want.
Even the much more efficient fluorescent lamps still waste over 50% in unwanted
heat effects.
What is true in electric light is also true in a measure in our present day radio
equipment. It is still extremely wasteful because most of the things we do now-a-days
are done in a round-about manner. We have not yet learned to exploit nature's forces
with a minimum of loss. All of our steam, electrical, and other power generators
are extremely wasteful and we recover only a fraction of the prime energy which
we put into them.
Coming to radio, we are slowly emerging out of the darkness and our various instrumentalities
are gradually becoming more efficient. As is well known, it took Marconi hundreds
of horse power of electrical energy to transmit the first weak signals across the
Atlantic by wireless. Today we easily span the earth to its furthest corners by
short waves, using as power a few dry cells, while the entire transmitting equipment
can be carried in a small satchel. Still engineers are not satisfied, because the
electromagnetic spectrum contains unknown regions which have as yet not been fully
exploited.
As we all know, electricity, radio, heat and light waves are all one and the
same thing. They are all electromagnetic waves and differ only in their frequency,
or wave lengths.
Originally, the discoverer of radio waves, Henrich Hertz, used ultra-short waves
in his experiments. When radio was very young these waves were not thought to be
useful and we used lower frequencies clustering above and below 1,000 Kc for radio
broadcasting. During the past 15 years we reverted to Hertz and began to use the
higher frequencies again, jumping from the low wave-band to broadcasting to around
10 MC (megacycles) for our short wave communications. Then FM followed around 50
MC, with television already heading toward the 100 MC mark. The ultra high frequencies
for radar and other military purposes are well above the 100 MC mark. That, however,
does not satisfy our research men, who see a great future in the still higher frequencies.
Thus the Klystron and Magnetron radio tubes can produce oscillations up to 10,000
MC and over.
But from 50,000 MC to 1,000,000 MC not much has been done. From 1,000,000 MC
and above, we pass into little known frequencies and from that point up to 100 million
MC we are brought into the region of radiant heat. From 100 million to 1,000 million
MC we step from radiant heat into the region of infra-red and then into light, ending
up in the ultra-violet spectrum.
What does all this mean to the radio technician? I believe that it is possible
in the future, that electronic radio tubes will be built which instead of putting
out invisible radio waves, will radiate actual light waves, at an incredibly efficient
rate.
You may ask "why do all this if an ordinary electric light bulb gives us excellent
white light right now?" The answer is - as I pointed out at the beginning of this
article - that we are getting our light now at the cost of a shameful waste of energy.
With future electron tubes, the story probably will be entirely different. But that
of course does not end their usefulness. Once we produce electronic tubes that can
give us oscillations at the rate of 1,000 million MC, our whole present concept
of radio will most likely be revolutionized.
Take only one application of such a tube - television. With a 1,000 million MC
tube it may no longer be necessary to scan as we must do today, because no other
and better means for television transmission is known now. But when electrical impulses
can be turned into light at will, the situation will be entirely different and undreamt
of results may be had when these instrumentalities are perfected.
It has long been the scientists' dream to utilize solar heat for man's emancipation
from sweat and labor. But light and heat are closely related in the spectrum, yet
man has not learned to tap solar heat except in a most round-about manner. Thus,
the radiant light which falls upon the city of New York would not only be sufficient
to run all of its transportation, elevators, electric lights, power for all of its
factories, etc., but would leave a substantial amount of energy over. But so far
we have not exploited this great store of power. The main reason is, that we do
not know enough about the unknown regions in the spectrum and do not possess the
key to unlock the solar energy directly. We can do it only through expensive transformation
of the sun's heat, such as ancient coal deposits, waterfalls, etc., which we turn
into electrical energy. But this is most wasteful on account of heat effects and
undesirable losses while the energy is piped over long distances.
Radio waves and light waves are one and the same thing. The sooner we can fully
explore the unknown regions in the electromagnetic spectrum, the sooner man will
approach the utopia of his dreams. Note: According to data supplied by the General
Electric Co., efficiency of tungsten-filament lamps may run from 6 to 12 percent
- that of a 40-watt fluorescent is approximately 45 percent.
Posted November 2, 2021
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