Hall of Fame
Updated March 27,
Isn't about time that the word
"Hall of Fame" gets applied to people that actually contributed
something to society, rather than overpaid people that do nothing
but sing or play ball? Here's an introduction to some of the innovators
upon whose broad shoulders you stand when you work in the microwave
industry: famous engineers, mathematicians and scientists that provided
the foundations for the microwave industry.
If you want to nominate a Microwave
God to our humble Hall of Fame, send info to
Microwaves101.com and you will win a free
pen knife if he (or she) makes the cut. There is room
for an unlimited number of inductees, so start shooting them in.
No microwave managers please!
On this page, you'll find the
classics--most of these guys you should know for their contributions
to electrical engineering as a whole. History-makers around WWII
have their own page, and modern-day geniuses now have a page to
call their own. Check them all out!
Go on to the second
page of the Microwave Hall of Fame.
Go on to the third
page of the Microwave Hall of Fame.
Go to our main microwave
Long before any study of microwaves occurred, Scotsman John
Napier, born in 1550, developed the theory of logarithms,
in order to eliminate the frustration of hand calculations
of division, multiplication, squares, etc. We use logarithms
every day in microwaves when we refer to the decibel. His
"numbering rods", constructed of ivory, became known
as "Napier's Bones", and comprised the world's first
slide rule. Some of his neighbors suggested that he was in
league with the powers of darkness... a trait that has often
been associated with successful microwave engineering! The
Neper, a unitless quantity for dealing
with ratios, is named after John Napier.
Microwave antennas often use a Cassegrain reflector. Not much
is known about Laurent
Cassegrain, a Catholic Priest in Chartre, France, who
in 1672 reportedly submitted a manuscript on a new type of
reflecting telescope that bears his name. The key features
are a secondary convex mirror suspended above the primary
concave mirror, that focusses light into the eyepiece which
is located in a hole in the primary mirror. The Cassegrain
antenna is an an adaptation of the telescope.
Christiaan Huygens was a Dutch scientist who lived from 1629-1695. Among many other scientific contributions (notably in astronomy), Huygens was the first to postulate the wave theory of light, in 1678. He was able to explain linear and spherical wave propagation, and derived the laws of reflection and refraction. Among those that refuted this theory was one Isaac Newton. It took a few centuries for scientist to eventually agree that Huygens was right (at least partially, due to the wave particle duality that is currently accepted).
Huygens was the first person in all time to measure how long a day is on a celestial body other than Earth, using a telescope that was powerful enough to see permanent features on Mars. OK, we are discounting that even cave people probably could noticed that the "day" on the moon is roughly equal to an Earth month as we forever see just one side of it.
Lazzaro Spallanzani, born in 1727 in Italy, had a huge
influence on many of the physical sciences, which is even
more remarkable because he was an ordained Jesuit priest.
Here in the Microwave Hall of fame, Spallanzani is remembered
because his Lettere sul volo dei pipistrelli acciecati,
published in 1794, recorded correspondence about his experiments
on the remarkable sense of direction of bats. Bats use sonar
to move about in the dark, which some might argue was the
inspiration for radar.
Alessandro Volta was born in Italy 1745. Volta was the first
one to ask and answer the question, "if I stack a bunch
of dissimilar metals such as zinc and silver in salt water,
can I make some cool sparks if I connect it with this newfangled
invention called "wire"?" This represented
the development of the voltaic pile, the first wet-cell
battery, which was the power source for all early experimentation
in electricity. The emperor of Austria made Volta director
of the philosophical faculty at the University of Padua
in 1815 for this fine work. His name is presently used more
than any other person in this Hall of Fame, in our estimation,
because the units of electromotive force (Volts) are named
in his honor. Volta died in 1827. Nominated by Arne Lüker.
Hans Christian Oersted was born in 1777 in Denmark, and
was a lifelong academic specializing in the physical sciences,
as well as an amateur philosopher, a follower of Kant. Oersted's
discovery in 1820 that an electric current would deflect a
compass needle was the first proof that electricity and magnetism
are like beautiful twin sisters Mary-Kate
and Ashley Olson, irresistible to engineers, and always
touching each other! The unit of magnetic field strength was
named the Oersted in his honor. One of Denmark's greatest
thinkers, Oersted founded the Polytechnical Institute in Copenhagen
in 1829, which is now known as the Technical University of
born in 1777 was Johann
Carl Friedrich Gauss. Born in Braunschweig, Germany, Gauss
is regarded by many as the most prominent mathematicianever.
His numbers work is too numerous to even be listed here and
much of it seems esoteric to engineers, such as his solution
a 17-sided polygon inside a circle. (This is what he wanted
on his grave stone)! He also proved that any integer can be
expressed as the sum of no more that three triangular numbers,
not something that you might use ever day. His name is used
every day in discussions of probability theory (Gaussian distribution).
He also was a major contributor to physical sciences, inventing
the heliotrope (for measuring long distances using sunlight)
and developed accurate methods for measuring terrestrial magnetism.
He helped install a telegraph system in Europe, at the same
time accomplished painter Samuel Morse was working on his
system in the United States. Let's not forget Maxwell's equations
includes two that are derived from Gauss (magnetic and electric
induction). The CGS unit of electromagnetic induction is the
"Gauss", in his honor. Gauss died in 1855.
Georg Simon Ohm was born in Erlangen, Bavaria (a region of
Germany), on March 16, 1787. Ohm's experimentation with voltage
and direct current led him to the fundamental relationship
that they are exactly proportional in a perfect conductor.
Ohm's Law (V=IR) is as basic to the study of electronics,
as Newton's Law (F=mA) is to classical physics. Ohm's Law
applies at DC, where he measured it, and just as well at microwave
frequencies. Semiconductors have been known to bend Ohm's
law, but it took more than a century for this to happen. Ohm's
idiot colleagues apparently dismissed his work, causing him
both poverty and humiliation. He died in 1854, but his name
is still used approximately one billion times each day! Nominated
by Arne Lüker.
Michael Faraday, born in 1791, is credited as the discoverer
of magneto-electric induction, the law of electrochemical
decomposition, the magnetization of light, and diamagnetism,
among many other contributions to chemistry and physics. He
did his research at the Royal Institution of Great Britain in London (thanks for the correction, Richard!) for a stipend
of 300 quid per year from the British government. Faraday's
name is immortalized in the Farad, the unit of capacitance.
Christian Andreas Doppler
was born in Austria in 1803. Being too much of a pencil-neck
for the family stonemason business, he learned mathematics at
the Vienna Polytechnic Institute. His theory of the apparent
shift in frequency when source or observer was in motion relative
to the other was proved using musicians on trains and train
platforms listening for what notes the others were playing.
He correctly predicted that the concept would prove valuable
in astronomy in determining celestial motion because of color
shifts. Doppler radar is used everyday, by pesky police radars
for one trivial example. He died young at age 49.
At the same time Faraday was working on EM theory, Princeton
Henry was also playing with large electromagnets, developing
one that lifted 750 lbs., partly because he was the first person
to consider source and load
impedance matching to maximize power
transfer. In his own words, one of Henry's experiments "illustrates
most strikingly the reciprocal action of the two principles
of electricity and magnetism". He was also the first curator
or the Smithsonian Institute, and his work on self-induction
is remembered today because the unit of inductance is the Henry.
Henry lived a full life, from 1797 to 1878.
In 1873, country-boy misfit James
Clerk Maxwell laid the foundations of modern electromagnetic
theory in his work, "A Treatise on Electricity and Magnetism"
in Scotland, which he wrote as a retired college professor.
Born in 1831, and nicknamed "Dafty" by his childhood
peers, Maxwell theorized that, if combined, electrical and magnetic
energy would be able to travel through space in a wave. If Maxwell
were here today, he would be pleased to see
his equations routinely solved many thousands of times per
second by today's three-dimensional structural simulators using
finite element analysis. Dr. James C. Rautio, founder of Sonnet
Software, Inc. (one of our sponsors!), seems to have made the
study of Maxwell a personal quest. He's a Distinguished Lecturer
of the IEEE for 2005, and his talk entitled The Life of James
Clerk Maxwell, is not to be missed, animated with at times
with different voice impressions of 19th century Scotsmen (div
ye ken?) You can download a copy of an excellent public-domain
biography of Maxwell, written in 1882 by his friend Lewis Campbell,
thanks to James Rautio, who personally scanned it into a pdf.
Its tucked up under "products" on the
Sonnet web site. For those of you that don't read much,
it has some great contemporary pictures!
1876, a U. S. patent was applied for:
"the method of, and
apparatus for, transmitting vocal or other sounds telegraphically…
by causing electrical undulations, similar in form to the
vibrations of the air accompanying the said vocal or other
Three weeks later Alexander
Graham Bell's famous sentence, "Watson, I want to
see you", was spoken into the first telephone. The same
month, Custer's army became human pincushions.
Bell was born a Scot in
1847 and came to the "New World" by way of Canada,
later settling in Boston. His portfolio of inventions is second
to none, but his life's work was mainly centered on helping
the deaf. The term bel (and decibel)
was named by Bell Labs scientists to honor him. Bell thought
the phone was too great a distraction, and refused to permit
one in his study! Bell died in 1922.
By the 1880s,
electrification of the world had begun, first for lighting, and
just as important, for motors. In the United States, a huge rift
developed between supporters of direct current systems (being deployed
by Edison), and supporters of alternating current (to be deployed
by Westinghouse). Eventually, Nikola Tesla
proved to the world that alternating current and his polyphase system
of generation, distribution and power delivery using the induction
motor were the answer to long distance, reliable electrical distribution.
New York City was wired with direct current for a time, and unreliable
DC trolleys and their sparking commutators gave the Brooklyn Trolley
Dodgers baseball team (today's L.
A. Dodgers) their name. During this time period, "Wizard
of Menlo Park" Thomas Edison performed despicable acts
on neighborhood pets to show the dangers of alternating current,
and eventually arranged for the first prisoner execution on August
6, 1890, using (of course) alternating current. Convicted
killer William Kemmler took eight minutes to die, even though
the procedure had been tested on a horse the day before. To see
the botched execution from the movie Green Mile, click
here (fair warning, this is a truly ugly event). The late 1800s/early
1900s were certainly the most interesting of modern times for technology.
You can read about this time period in books
such as Tesla, Man out of Time, by Margaret Cheney.
Charles Proteus Steinmetz
in his cabin near Schenectady. Looks like the museum incorrectly
painted the replica table white!
Steinmetz was a socialist,
which is what brought him to the United States (he had to
flee Germany after writing political essays). He was also
an environmentalist, an anti-racist, a protagonist of electric
cars to reduce pollution, and a big fan of cigars. He preferred
to live in a camp near General Electric's Schenectady plant,
using a canoe as his fair-weather office. He had 200 US patents.
Proteus Steinmetz (1865 - 1923) was a German-born mathematician
measuring just four feet tall, but was giant of a technologist.
For a time, he was the brains of the Edison Electric
company. He realized the major benefit of alternating current
over his boss's narrow-minded, DC approach, which is the ability
to efficiently transform up and down in voltage so that power
transmission could be performed at very high voltage at reduced
loss. Edison was indeed a victim of his "not invented
here" attitude. Through a merger orchestrated by railroad
robber-baron J. P. Morgan between Edison Electric and Thomson
Houston Electric Company of Lynn Massachusetts, Edison's name
was removed from the combined company, General Electric. Although
Tesla must be credited with inventing
the induction motor which changed the world (due to its inherent,
year-after-year reliability), Steinmetz was the first to provide
a mathematical interpretation of how an electric motor worked,
using the phasor concept. His work on hysteresis allowed motor
designers to optimize motor efficiency without continuous
tinkering with prototypes.
Edison might be spinning in his
grave these days, as high-voltage DC transmission line haves made
a comeback of sorts. Once the problem of up/down converting is solved
(which is an expensive proposition), DC has two advantages over
AC: lower peak voltage for the same power (less opportunities to
arc), and the skin depth
at DC is infinite. Every gram of copper in a DC transmission line
is used to move power equally, this is not true for AC. Therefor
DC has a loss advantage which can be appreciable for large diameter
lines. Here's some info
on HVDC power transmission lines.
In 1884, British physicist John Henry Poynting (1852-1914)
published his description of the Poynting Theorem, which describes
the vector that bears his name. The Poynting
vector determines the direction and magnitude of electromagnetic
radiation, and gave rise to what is known as the Right Hand
Rule to determine power flow. Today, metamaterials
routinely demonstrate lefthandedness, yet still obey Poynting's
Theorem, even though he probably could not have envisioned
this development. Among
his other accomplishments, Poynting wrote a physics text
book that was in print for 50 years!
Several years after Maxwell's famous treatise, German Heinrich
Hertz (1857-1894) conducted experiments that proved Maxwell's
theories were correct. Hertz began testing these theories
by using a high-voltage spark discharge (a source rich in
high-frequency harmonics) to excite a half-wave dipole antenna.
A receive antenna consisted of an adjustable loop of wire
with another spark gap. When both transmit and receive antennas
were adjusted for the same resonant frequency, Hertz was able
to demonstrate propagation of electromagnetic waves. And thanks
to Philip, we now have Mr. Hertz's correct photo!
In another experiment, Hertz
used a coax line to show that electromagnetic waves propagated with
a finite velocity, and he discovered basic transmission line effects
such as the existence of nodes in a standing wave pattern a quarter
wavelength from an open circuit and a half wavelength from a short
circuit. He then went on to develop cylindrical parabolic reflectors
for directional antennas, as well as a number of other radio frequency
(RF) and microwave devices and techniques.
Others soon built on Hertz's work. In 1894, 20 year old Guglielmo
Marconi began experiments in Italy sending a wireless signal
using Morse code, at first for short distances, and ultimately
thousands of miles. Marconi was the son of a wealthy Italian
businessman and an Irish mother who was part of the Jameson
family whose distilled products were (and are) well known. He
had limited education and no formal training as engineer or
scientist, just an idea that wireless communications would one
day render the telegraph obsolete, and the wherewithal and family
support to pursue his dream. Marconi brought together the "perfect
storm" of engineering curiosity (notice we didn't say "scientific"),
confidence, financing and ego that comes along once in a lifetime
to rattle the establishment out of bed and change the world.
His only equal today would be be Bill Gates.
Marconi faced resistance, resentment
and reprisals from many well-known scientists of the era, and almost
lost his personal fortune. His high-tech startup of the '90s, The
Wireless Telegraph & Signal Company (a U.K. company) was soon
renamed Marconi's Wireless Telegraph Company. This business began
by installing company-owned and operated wireless communications
onto ships to communicate with huge
installations on key coastlines, while the founder pursued ground
communications across the Atlantic. It is ironic that Marconi's
methods of trial and error for tuning his equipment would have taken
much longer if not for access to transatlantic cables owned by the
telegraph companies his technology would compete with. Marconi received
the Nobel physics prize of 1909 for his work, shared with German
Ferdinand Braun. By 1911, "Marconigrams"
had helped capture a famous murderer and in 1912 enabled the rescue
of Titanic survivors. Marconi was the first experimenter to notice
that transmission during daylight hours was more prone to noise
than at night, which was later explained by Heaviside as due to
the "Marconisphere" (now known as the ionosphere). Approximately
350 civilian Marconi wireless operators were killed at sea during
the first World War, as the wireless shed was a crucial target for
maritime marauders. Although Marconi was the singular force behind
long distance wireless communications, he admitted he didn't really
know how it all worked. Some years later the scientific community
discovered that Marconi's idea that longer wavelengths would travel
farther around the globe was incorrect, and Marconi's amazing 300,000
watt steam-powered spark gap transmitters, building-sized capacitor
banks and multi-mile antenna elements were unnecessary at higher
frequencies (short waves). Marconi died in 1937, to learn more about
his life and that of murderer Harvey Crippen, go to our book
page and order Thunderstruck. Marconi's company has long
since has been chopped up and digested into BAE and Ericsson among
A lot was happening in radio around the previous turn of
the century. John Ambrose Fleming, who had worked with Maxwell, Marconi,
and Thomas Edison, invented an "thermionic valve",
better known today as a diode tube (Brits still
refer to tubes as valves.) Marconi's receiver used something called a coherer in order to pick off the Morse code signal from RF; later radios used crystal detectors (cat's whiskers) to detect the audio. Fleming's valve was patented, and soon Lee de Forest made a major discovery as he tried to find a way around Fleming's patent (more about that later). Fleming's valve made use of a discovery by Edison when he was trying to figure out why his light bulb was burning out. The Edison Effect is what happens when conduction occurs across a vacuum when one electrode is heated. Edison couldn't see any commercial applications of this effect and essentially discarded it. See our page on detectors for a little more history that tries to put this all in perspective. Fleming also came up with an equation
that expressed the impedance characteristics of high frequency
transmission lines in terms of measurable effects of electromagnetic
waves, and coined the term "power factor".
As the son of a minister, Fleming got his shorts in a knot about Darwin's theory of evolution.
Father Landell de Moura is a little known pioneer of wireless
transmission of voice. In 1900 he publicly demonstrated voice
transmission while others were merely transmitting Morse code.
In 1901 he received a patent in Brazil for "equipment for
the purpose of phonetic transmissions through space, land and
water elements at a distance with or without the use of wires".
He then traveled to the United States where he was awarded three
patents in 1904: the "Wave Transmitter" which is the
precursor of today's radio transceiver, the "Wireless Telephone"
and the "Wireless Telegraph". His sketches have survived,
and his equipment has been duplicated in modern times to show
he was on the right track. Read his fascinating
Wave Transmitter patent here. Nominated by Ricardo, an Electrical
Engineering student at University
of Campinas, Brazil, and fan of microwaves101.com!
Reginald Aubrey Fessenden,
born in Canada in 1866, was a huge pioneer of wireless. He
was the first inventor to demonstrate transmission of voice
in December 1900 (Marconi thought that Morse Code was good
enough for all communication needs), and his first transmission
involved a weather report! He was the first to think in terms
of continuous wave (CW) transmissions instead of the pulsed
spark-gap transmitters of the day. He built some clever high
speed alternators to provide up to 200 kHz, 250 kW signals
for transmission, before anyone had developed a useful electronic oscillator.
He also developed the theory of heterodyne detection and
coined that word (demonstrating and patenting the first mixer), but didn't have a practical, stable source to reap its full benefits in a radio receiver. Did we mention that he invented 500 other
things too? A rare combination of genius and entrepreneur,
thanks to Brian, he is now in the Microwave Hall of Fame!
Brian wishes to point out
that Fessenden, Tesla, Charles Steinmetz and Ernst Alexanderson
all worked for Edison. Is the top genius the one who can make
business out of the genius of others? How many similar genius’s
worked for Bill Gates and helped him make his billions and
whom we will only hear about 100 years from now if ever?
Alfred Abraham Michelson (1852-1931) was born in Prussia to Jewish parents and emigrated to the US when he was two years old. Pronounced "Michealson", he first measured the speed of light in 1878 resulting in an estimate of 300,140±480 km/s (not much different from other experimenters at the time). This privately funded experiment used mirrors separated by just 152 meters, and was the start of a life-long passion.
Michelson was the first US scientist to win the Nobel prize for Physics, in 1907 "for his optical precision instruments and the spectroscopic and metrological investigations carried out with their aid". Later he continued to improve measurement accuracy of the velocity of light, and his most accurate experiments occurred after he was 70 years old. By 1926 he had data to show 299,796±4 km/s, from a measurement between Mt. Wilson and Mt. San Antonio in California in today's Angeles National Forest. To get this accuracy, distance needs to be accurate to centimeters across the 35 km separation. In 1929 he set about to measure speed of light in vacuum in a one mile pipe. He died in the middle of the experiment, which turned out to be corrupted ±10 km/s by the slipping San Andreas fault, alluvial soil and sea tides.
Without an accurate value for "c", radar would be in serious trouble. Learn more about speed of light measurement here. If you have the opportunity to visit the Naval Air Weapons Station at China Lake, you might visit "Mich" labs, named after Michelson, which has a great exhibit of Michelson artifacts in the lobby. Be sure to pronounce it "Mike Lab"!
The Michelson-Morley experiment is regarded as the greatest failed experiment of all time. Using the amazing interferometer they developed together (think pool of mercury floating a one-foot thick slab of granite) in 1887 at what is now Case Western Reserve University, M&M set out to measure how the "aether wind" affects the speed of light. This hypothesis proved wrong, aether wind was not detected, and the second scientific revolution had begun. Read Michelson and Morley's 1887 American Journal of Science paper here!
Michelson was the first person to measure the diameter of a star (Betelgeuse) in 1927.
Karl Ferdinand Braun (1850-1918) worked on wireless telegraphy.
His inventions include the first semiconductor, the point-contact
diode used in "crystal" radios; before that receivers
had to use something called a "coherer" to convert
RF to baseband. He also invented the first cathode-ray tube
to provide a visual display, the precursor to radar screens,
oscilloscopes and video screens alike. Today the Ferdinand-Braun-Institut
für Höchstfrequenztechnik in Berlin carries out
some great work in microwave technology, especially in flip-chip
coplanar-waveguide MMICs. Braun shared the 1909 Nobel prize
for physics with Marconi.
Textronix named a street "Karl Braun Drive" at their Beaverton facility. They also named streets after Schottky, Terman, Shannon, Zworykin and more electronics' pioneers. Check it out!
Lee de Forrest (1873-1961)
was a prolific inventor (180 patents) and is regarded as inventor
of the three-terminal tube, which he called the audion. Many
regard him as the father of radio. By adding the grid to Fleming's
diode "valve", de Forest showed how to control the
signal but did not achieve amplification with the three terminal audion, which in hindsight is arguably one of the top ten inventions in the history of the world. Later
inventors, most notably Armstrong, built on de Forest's discoveries
and radio soon became a rage; even non-electronics companies
such as Radio
Flyer cashed in on the name. De Forest disliked the word
"wireless", and helped populate the new word "radio"
which was derived from radiation. Many early radio inventors
were pawns of giant industrial companies such as Westinghouse,
AT&T and General Electric, and the fight over patent rights
was fierce and discredited some of the best minds in the field.
De Forest suffered as much as any, in the patent fight of the century for who invented the regenerative receiver. Even then almost all radio engineers accepted that Armstrong was the inventor, but patent law can be a tangled web indeed. De Forest went through four marriages,
but lived a long life and saw radio move from curiosity, to
invaluable war and peacetime communication tool, to mass media
outlet. Lee spent many good years in Hollywood, among other
an Oscar for developing a way to add sound to motion pictures.
Late in life he became disillusioned with radio, as he was neither
a fan of pop music nor advertising. Neither was Elvis Costello back in 1977... Nominated by Brian!
Lee de Forest
William Henry Bragg
In 1915 a father and son team won the Nobel prize for Physics. William Henry Bragg (1862-1842) and William Lawrence Bragg (1890 to 1971) developed the science of crystallography using X-ray diffraction. William Lawrence Bragg remains the youngest Nobel laureate at 25 years of age. How is your career going? Here at Microwaves101, we are happy to celebrate the 101st anniversary of crystallography in 2013!
In microwave engineering, semiconductors are analyzed using crystallography. We have also adopted a dual meaning: Bragg frequency refers to the frequency where a periodic structure suffers from additive interference and hence ceases to function. Examples of Bragg frequency can be found in studies of slow wave lines and artificial transmission lines.
William Lawrence Bragg
Mad scientist Oliver
Heaviside's research in transmission-line theory was first
applied to telegraphs, including the transatlantic cable, but
microwave engineers use his concepts to this day. A mathematician,
he rewrote Maxwell's messy equations into their simple, vector-calculus
form. He predicted the E-layer of the ionosphere, which allows
propagation of electromagnetic waves around the curvature of
the earth. A trendsetter years ahead of Ed
Wood, he painted his nails pink!
Hendrik Baekeland was born in Ghent, Belgium on November
14, 1863 to poor parents, yet earned his doctorate at University
of Ghent by the age of 21. He emigrated to the U.S in 1889,
and made his original fortune selling a process for photographic
paper to George Eastman for $1,000,00 in the 1890s. Later experimentation
by Baekeland resulted in discovery of the very first plastic,
a thermoset compound created from formaldehyde and phenol that
became known as Bakelite.
Bakelite was a huge enabler for bringing radio to the masses,
not just as a substrate for mounting electrical components due
to its insulating property, but also as the material for mass
Click this link to go to the radio museum and notice the
progression from hand crafted wood cabinet to molded enclosure
during the 1930s. There's at least one Bakelite
museum! Baekeland died in 1944, we can't help but wonder
what his coffin was made of!
Marconi was awarded the Nobel prize in 1909 for his "wireless
telegraphy" work , the U.S. Supreme Court revoked Marconi's
patents since Serbian-American genius Nikola
Tesla had taken out a patent for radio communications
as early as 1897. Doesn't Tesla look smug in this picture?
Tesla's life has taken on legendary status, having obtained
more than 700 U.S. patents. Perhaps because he was jerked
around by Thomas Edison to the tune of $50,000 early in his
career, we can thank Tesla for perfecting alternating-current
power distribution and fluorescent lights. Some of his other
inventions include a unique steam turbine, liquefaction of
nitrogen, and the awesome Tesla coils from which he coaxed
10,000,000 volts to light up the Colorado sky. No other inventor
has has more articles written about him. Nikola Tesla is
quite possibly the greatest engineer that ever lived;
you can quote the Unknown Editor on that. You can find over
100 articles with "Tesla" in the title on the IEEE
web site. Here's a second web
site with info on Tesla that we found useful.
Watch David Bowie play
Tesla in the movie The
By 1894, Sir Oliver George was conducting experiments noting that
directional radiation was obtained when he surrounded a spark oscillator
with a metal tube. In 1897, Lord
Rayleigh (John William Strutt) proved mathematically that waves
could be propagated inside a hollow metal tube. Rayleigh also noted
the infinite set of modes of the TE or TM type which were possible,
and the existence of a cutoff frequency. Waveguide was essentially
forgotten, however, until it was rediscovered independently in 1936
by George C. Southworth at AT&T (Bell Telephone Labs) and W.L.
Barrow at MIT.
Up until this point, focus had
been on sending and receiving communication signals. As the new
century progressed, scientists worked with longer and longer wavelengths
to achieve greater and greater distances.
In India, however, J.C.
Bose was working with shorter and shorter waves. In 1895
Bose gave his first public demonstration of electromagnetic
waves, using them to ring a bell remotely and to explode some
gunpowder. The wavelengths he used ranged from 2.5 cm to 5
mm. Think about that. He was playing at 60 GHz over one hundred
years ago! Bose's investigations included measurement of refractive
index of a variety of substances. He also made dielectric
lenses, oscillators, receivers, and his own "polarization
In 1911, only three years after building
the first helium liquefier, Heike
Kamerlingh-Onnes discovered that mercury loses its electrical
resistance entirely when cooled below 4.2 K in a liquid helium
bath. Why do we include the discoverer or superconductivity
in the microwave hall of fame? Stick around, the best in microwaves
is yet to come with the advent of high-temperature
scientist from Kcynia Poland, Jan
Czochralski, was many years ahead of his time. In 1916
he developed a method for growing single crystals, which was
basically forgotten until after World War II. Today the semiconductor
industry depends on the Czochralski method for manufacturing
billions of dollars worth of semiconductor materials. He was
accused of being a Nazi sympathizer but was later acquitted
and died in Poland in 1953. What a wacky world, Bill Gates
is the richest man on earth and most people don't even know
how to pronounce "Czochralski!"
Schottky's name is embedded in solid-state physics (Schottky
effect, Schottky barrier, Schottky contact, Schottky diode).
Born in 1878 in Germany, he was a contemporary of Einstein and
Max Planck. His work included superheterodyne receivers, noise
theory, and radio tube work such as invention of the tetrode,
but his most important contribution to microwaves is no doubt
his investigation of metal-semiconductor rectifying junctions
(published in 1938), which is the basis for the gate contact
of all MESFETs. He died in 1976, one year ahead of Elvis.
While still in high school, Edwin Howard Armstrong
erected a 125 foot radio mast at his parents' house in Yonkers,
New York, to receive the weak radio signals of the day. While
still in college in 1912, he invented a feedback circuit based
on Lee de Forest's three-terminal audion tube that provided
the first usable electrical amplifier, and submitted a patent for the regenerative receiver in 1913. Think about this: before
Armstrong, the only "amplifiers" that existed were
the mechanical relays used to boost voltage on long telegraph
lines! Armstrong won the triple crown of electrical engineering,
soon inventing the superheterodyne
receiver, then inventing frequency-modulation (FM) broadcasting.
He cashed in on his patents, in spite of a corporate war between
AT&T and RCA over who really invented the feedback amplifier,
Armstrong or de Forest, but he spent more time in court than
Perry Mason. On January 31, 1954 he committed suicide by leaping
from a building; an ironic end to a brilliant man who often
scared his co-workers by fearlessly scaling antenna installations for fun.
Dirtbag lawyers and corporate greed aside, the IRE (predecessor
of IEEE) gave credit to Armstrong for the key inventions of
radio. Nominated to the Hall of Fame by OAH of Towaco NJ!
Read Empire of the Air by Tom Lewis
for more info on the history of radio.
As radio applications grew more
sophisticated (and popular), stations started broadcasting regular
commercial programs. By 1920, the US Department of Commerce stepped
in and began issuing radio licenses, and in 1921 formally declared
a special service category (and corresponding transmission wavelength)
for commercial stations.
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