RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
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and text used on the RF Cafe website are hereby acknowledged.
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.
As a case in point
about my claim with an earlier post featuring
Bob Berman's factoids on astronomy, this article from a 1956 edition
of Popular Electronics illustrates how vital electronics are in the various
fields of science. It has only been fairly recently that astronomers have been "looking"
at stars and planets outside of the visible wavelengths. Renditions of the sky in
both shorter and longer wavelengths show in some regions a vastly different universe.
In 2015, a comprehensive mapping of the entire known
universe in the microwave realm revealed the largest contiguous
feature ever detected - dubbed "The Cold Spot." Such discoveries could not be made
without sophisticated electronics. The same can be said of medicine, biology, mechanics,
finance, etc. Reported here are some of the earlier detections of radio signatures
from our planets. Information gleaned from planetary and cosmic studies helps scientists
better understand the Earth and its history, as well as its likely future. In the
same manner as the words from John Denver's song
Calypso suggest, "to live on the land we must learn from the sea," so,
too, must we learn from the heavens.
Radio Waves Heard from Jupiter and Venus
Giant antenna atop Naval Research Laboratory measures 50 feet
across. Signals received from Venus are recorded below by astronomer T. P. McCullough.
BTW, notice the 48-star flag American flag flying over the Naval
By O.P. Ferrell
Radio Waves spanning interplanetary space are now a certainty. The dreams of
science fiction writers and the predictions of Nikola Tesla are closer to reality.
Positive identification of radio waves generated, by means unknown on both Jupiter
and Venus has been established. Work is progressing rapidly in this field by teams
of scientists in Europe, Australia and the United States, where giant radio telescopes
are now in use.
Radio signals from beyond the earth have been known for about twenty years. But
these came mostly from turbulent areas of outer space, where intense electrical
activity accompanies the formation of new stars and the gigantic eruptions of distant
suns beyond the reach of even the largest telescopes. Only lately have radio star-gazers
been hearing odd noises from our relatively quiet and astronomically "dead" next-door
neighbors, the planets.
Thundering Jupiter. Electromagnetic
waves picked up from Jupiter lack a clearly defined frequency, yet are best heard
around 22 megacycles. With their frequency distribution being random throughout
a wide band, the signals sound just like static caused by storms. Since Jupiter,
like Earth, is surrounded by a gaseous atmosphere, it is quite possible that the
radiation it sends out is a sign of turbulent weather.
Helical antenna array for the radio telescope at the Ohio State
University consists of 96 spiral coil elements to refract the incoming signals.
Ultra-sensitive superhet receivers are checked by technician
to assure low internal noise for clearer recognition of marginal signal patterns.
John Denver's "Calypso"
Lending probability to this theory is the electrical behavior of the weather-bearing
layers in our own terrestrial atmosphere. About 50,000 thunderstorms per day pass
over the face of the earth. About 2000 are going strong at anyone moment, giving
off about 100 lightning flashes every second. Each lightning flash is a 3-millisecond
burst of 2000-3000 amperes, reaching peaks around 10,000 amperes. That's a lot of
electrical popping for our small planet. To radios on Jupiter, it would probably
sound the same way that the waves from Jupiter sound to us.
Hot Venus. Until a few months ago, it seemed that Jupiter was
the only planet to radiate electromagnetic waves. Yet earlier this year, Dr. John
Kraus of Ohio State University also caught signals from Venus, the planet which
is prominent in the sky as the Evening and Morning Star. The Naval Research Laboratory
in Washington independently made the same discovery.
Signals from Venus reported by the Navy differ from those of Jupiter. They are
not generated by electric disturbances of the atmosphere, but by the molecular activity
of heat. The wavelength of the Venus signals stays fairly constant at 3 cm., which
corresponds to a temperature of more than 212° F - the boiling point of water.
Any water existing on Venus would therefore be in the form of steam. This makes
it unlikely that living organisms as we know them could exist on that planet.
Giant Antennas. No ordinary antenna will catch these faint signals
from the stars. Instead, radio astronomers employ huge parabolas or dipole arrays
to concentrate the dim stellar mutterings at the receiver input.
For instance, the giant parabola atop the Naval Research Laboratory Building
in Washington acts like the mirror in an ordinary optical reflector telescope. All
the energy is focused in a single point at the tip of the central pole, from whence
it is funneled to the receiver. The antenna is automatically rotated so as to keep
pointing at the same target in space, regardless of the motion of the earth. Signal
gain attainable with this antenna is over one million.
The optical refracting telescope, exemplified by ordinary field glasses, also
has its electronic equivalent. Helical antennas, looking like vast coil-spring mattresses,
bend the incoming radio waves as a deflection coil bends the beam in a TV tube.
In this manner, they concentrate the incident energy at the pickup point. By stringing
a large number of coil-shaped structures in an array, the gain is multiplied in
proportion to the total antenna size. On this principle, Ohio State University built
the 96-coil unit, which successfully eavesdropped on Venus.
Whether similar waves will be heard from Mars is still an open question. As Mars
draws closer to Earth this year than it has at any time within the past 20 years,
the chances of intercepting its radio waves, if any, are greatly increased. Experiments
continue as the massive antennas seek out our brother and sister planets in the
Posted December 29, 2021 (updated from original post on 6/24/2015)
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