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 The market for
high-performance RF, microwave, analog, and digital circuit simulation software
is
dominated by a small number of vendors whose products are effectively
mandated for official project proposals and regulatory deliverables. These
vendors most familiar to all of us in the field maintain their premium pricing
not solely through superior technical merit, but through a systematic practice
of regulatory and procurement capture. By influencing standards bodies,
government procurement specifications, and academic curricula, these incumbents
ensure their tools become the only legally or practically acceptable options for
signed-off engineering work. The pattern is consistent: a smaller company...
 Here are a couple more
electronics-themed comics from vintage Radio-Craft magazines. Artist
Frank Beaven, who created a huge number of comics and advertisements (e.g., Eveready
batteries, Zippo lighters) for technical and other types of publications (Saturday
Evening Post, New Yorker, Esquire), did both of them. Beaven
must have a fan base since many examples of his drawings are offered for sale on
eBay. Most of his comics credit reader suggestions as the basis for the subject.
I have to admit to not really "getting" the gag in the top comic. Maybe Sinatra's
voice strained the frequency response of simple tabletop radios of the day. The
bottom comic is one of a series entitled ...
 This custom
Communications Engineering crossword puzzle contains some words particular to
radio, radar, analog and digital circuits, components, and other tech-themed words
and clues. Each week for two decades I have created a new technology-themed crossword
puzzle using only words (1,000s of them) from my custom-created lexicon related
to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will
never find among the words names of politicians, mountain ranges, exotic foods or
plants, movie stars, or anything of the sort. You might, however, find someone or
something in the otherwise excluded list directly related to this puzzle's technology
theme, such as Hedy...
 The "Monthly Review" column appearing in
Radio-Craft magazine was an assorted collection of news tidbits about
electronics and communications industry happenings, similar to
contemporary magazines. Looking back to 1947, the world was hopeful about the future
as World War II was finally over and even the loser countries were focusing
on how their societies would be shaped by technology and lessons learned in the
preceding seven to ten years (depending on when a country entered the war). Two
items here are particularly interesting because they refer to ongoing research into
large screen televisions and video phones (aka "televisers"). Large screens at the
time meant either...
 One of the Notable Tech Quotes which has
appeared on RF Cafe is, "The nice thing about standards is that you have so many
to choose from," by computer scientist Andrew Tanenbaum. In the middle of the last
century, a change in the fundamental understanding of current flow precipitated
what has become a very large opportunity for people to misunderstand descriptions
of
current direction caused by a difference in voltage potential
(voltage) - depending on the era a particular description was written. Beginning
with Benjamin Franklin, electron current flow was assumed to be from positive to
negative, ostensibly but incorrectly, because a positive thing must contain an excess...
 "Fortune reports that Elon Musk's SpaceX
and Tesla are constructing Terafab, a chip manufacturing complex that Musk says
will become the largest and most valuable building on Earth. 'Terafab
Texas will be the largest and most valuable building on Earth by far. And it
will be stunningly beautiful,' Musk wrote on X. The New Century Global Center in
Chengdu, China, currently holds the record for the world's largest building at about
18.9 million square feet. Terafab's planned 100 million square feet would exceed
that by more than five times. Texas Gov. Greg Abbott (R) said in a press release
that 'the first phase of the Terafab project represents a capital investment of
more than $16.8 billion and will create 3,000 new jobs...
 Computer analysis in 1976 was a job performed
on a corporate, university, or government mainframe. Radio Shack's TRS-80 came
out in 1977, but it did not have the capacity to calculate and plot antenna gain
charts like the one in this QST article. Yes, an ambitious programmer could
write the code necessary to perform the double integrals presented in the article,
but to do all the figuring needed to create all the graphs in Figure 4, the job
would just about be finishing up today - and that's not too much of an exaggeration.
For some reason the authors never mention what computer was used or where it was
based. When I saw the title of "Loops vs.
Dipole," I expected the loop to be...
 Even with having been granted more than
400 patents in his lifetime, and being a major player in the realms of energy, data
storage, and semiconductor research and manufacturing, you - as well as most people
- have probably never heard the name
Stanford Ovshinsky. He was somewhat of a celebrity in the 1960s
and 1970s when working hard to promote his concept of "glassy semiconductors," -
aka Ovonic devices. Ovonics are amorphous materials that are used for making switches
for digital logic and memory devices. Either the Ovshinsky process did not pan out
for high volume commercial production or some other technology displaced the what
it was hoped to dominate...
 If I told you that Lester William Polsfuss
is widely credited with being a major player in the pioneering of electric guitars
due to his solid-body (no acoustic resonance chamber) designs, you might wonder
where I came up with that claim. However, if you know that Mr. Polsfuss is the surname
of Les Paul, then you would quickly agree. As if being a popular musician and, along
with wife Mary Ford, selling millions of records wasn't enough, Les Paul was
also an experimenter and inventor in the electronic music realm. This article entitled
"Les Paul: Technician and Musician" appeared in a 1958 article
in Radio-Electronics magazine, and was at the time a contemporary look
inside his...
 Sam Benzacar, of Anatech Electronics, an
RF and microwave filter company, has published his August 2026 newsletter that,
along with timely news items, features his short op-ed titled "Filtering
for Quantum: A Problem No One's Talking About." Sam aptly points out that as
quantum computers scale in size, specialized laboratory-built components become
both expensive and a schedule liability for development efforts. When a handful
of qubits was considered breakthrough-amazing, building all the parts in-house made
sense since processes and materials were being invented in the process of doing
so. However, at the point when thousands of filters, amplifiers, and other types
of components routinely manufactured...
 Georg Simon Ohm's discovery of the relationship
between voltage, current, and resistance revolutionized our understanding of electrical
circuits. Ohm's Law provided a simple, yet powerful mathematical tool that has become
essential to both theoretical physics and practical engineering. Although it was
initially met with skepticism, Ohm's perseverance and commitment to his scientific
work ultimately transformed the way we interact with electricity, influencing technologies
that define the modern world. His legacy lives on not only in the equation that
bears his name but also in the unit of electrical resistance - the ohm - that honors
his contributions to science...
 When you think about it, the speed at which
a human being is able to accurately copy
Morse code is limited by the same kinds of processes that limit
the speed at which binary data can be sent between electronic transceivers (modems).
Noise introduced into the signal at both the transmitting and receiving ends or
in the transmission path connecting the two, degrades the ability of the receiver
(electronic and human) to discern between a "1" and a "0." It can take the form
of electrical or audio interference and distortion. Phase noise in the electronic
realm is sort of the equivalent of an irregular sending human hand that cannot maintain
equal dwell times for dits and dahs, thus making the recognition...
 Why Phase Stability Matters During RF/Microwave
Testing. When engineers evaluate RF test cables, specifications such as insertion
loss, VSWR, shielding effectiveness, and connector type typically receive the most
attention. Yet for many Vector Network Analyzer (VNA) applications, one characteristic
can have a greater impact on measurement accuracy than all of these combined: phase
stability. Phase stability refers to a cable assembly's ability to maintain a consistent
electrical phase relationship when subjected to movement, flexing, temperature changes,
or repeated...
 Magnetic amplifiers (aka "mag amps") use
a property of saturated core inductors (saturable reactors) to obtain signal amplification
via a transformer-type plus diode-assisted voltage multiplication.
Magnetic amplifiers were preferred over vacuum tube amplifiers
in some circuits because they do not require a high bias voltage, are generally
smaller in size, are quite robust and are practically immune to microphonics. Their
biggest limitation is bandwidth. The high number of turns in the core provides a
lot of interwinding capacitance so the self-resonant frequency is in the low megahertz
range. Additionally, the need for the magnetic amplifier reactor to operate in a
saturated condition further...
 Anritsu has been a global provider of innovative
communications test and measurement solutions for more than 120 years. Anritsu manufactures
a full line of innovative components and accessories for
RF and Microwave Test and Measurement
Equipment including attenuators & terminations; coaxial cables, connectors &
adapters; o-scopes; power meters & sensors; signal generators; antenna, signal,
spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth &
WLAN testers; PIM testers; amplifiers; power dividers; antennas. "We've Got You
Covered."
 The National Company, of Malden, Massachusetts,
which made this
cesium-based Atomichron in the mid-to-late 1950s, began life as
a toy manufacturer. It had an output frequency at the nominal resonance frequency
of cesium - 9192.631830 MHz - and was accurate to better than a second in 600
years. The unit was 7 feet tall and weighed 500 pounds. Modern cesium standards
are more stable and are portable. As of January 2013, the NIST-F1 cesium fountain
primary frequency standard is accurate to within one second every 100 million years!
That's a tad better than the Atomichron, non...
 This Bell Telephone Laboratories (aka Bell
Labs) advertisement appearing on the inside back cover of the 1958 issue of
Radio & TV News magazine celebrated the 10th anniversary of their
announcement of the world's first
point contact transfer resistance (transresistance) semiconductor
device - aka the transistor. John Bardeen, William Shockley and Walter Brattain
recorded the monumental event in a lab notebook on December 23, 1947 - a nice Christmas
present for the world! The trio's invention was not like the robust bipolar
transistors used today, or even ten years later in 1958. Rather than employing point-contact
"cat's whisker" metallic probes for making the emitter and collector...
 For many years, I have been scanning and
posting schematics & parts lists like this one that appeared in radio and electronics
magazines in the middle of the last century. Most use vacuum tubes. This
General Electric Model 280 Farm Radio "Radio Data Sheet" was in
the May 1947 issue of Radio-Craft magazine. The Radio Museum website has
more information on the GE Model 280 Farm Radio. Farm radios were designed to work
on storage batteries since until the Rural Electrification Act of 1936 was put into
effect, most rural properties had no commercial AC electric power service. 11 years
later, work was in progress to light up the entire country, but many locations had
to wait while resources...
 Here are a couple new-old
tech-themed comics from vintage Popular Electronics magazines.
Both have a Ham radio theme, so maybe you need to have been there to appreciate
the scenario... or maybe not. It is possible that the presence of clothes pins on
twin lead or ladder line could de-tune the line, and could crush the internal dielectric
of a coaxial line. There is no metal on boxer shorts, but maybe the clothes pins
are the type with a metal spring. For the other comic, you just need to know what
••• --- ••• is to get it. Enjoy...
 Question: If a fuse is rated at 3 amps,
at what value of current should it "blow?" Answer: Not at 3 amps. As this
Littelfuse company advertisement from a 1954 issue of Radio & Television
News magazine informs us, fuse ratings do not indicate the current value at
which a fuse opens to protect a circuits, but rather the maximum current level at
which it will NOT blow (open circuit). The same goes for circuit breakers. Various
types of fuses are available to handle certain types of applications. For instance,
a highly capacitive load will according to the well-known equation iC(t) = C * dv/dt
could draw a very large amount of initial (inrush) current if there is not enough
series resistance to limit it to prevent...
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The RF Cafe Homepage
Archive is a comprehensive collection of every item appearing daily on this
website since 2008 - and many from earlier years. Many thousands of pages of unique
content have been added since then.
 While this article is directed at amateur
radio operators who want to explore working in the microwave bands, it is good fodder
for anyone who wants a fundamental introduction to
waveguides, resonant cavities, distributed elements, and atmospheric propagation.
If that describes you, and particularly if you have formulaphobia, then start reading.
Even though the article appeared in a 1952 issue of Radio & Television News,
the list of frequency band allocations are not much different than today so the
information is useful. Unknown to many is that in the early part of the last century
Amateurs pioneered the use of microwave bands when the Federal Communications Commission
(FCC) allocated the spectrum to them since many "experts" considered it unusable...
 In your rare few minutes of the workweek,
try your hand at this "Electronics
Helix Puzzle," provided by Mr. James Kimsey in a 1971 issue of Radio-Electronics
magazine. It it not as much of a challenge as a classical crossword puzzle, but
is still worth attempting. In some ways, though, if you get stuck on a word there
is more help available with a standard crossword because there are more than just
two (the first and last letter in this case) intersecting letters available to help.
If after completing this Electronics Helix Puzzle you would like to try your hand
at one of those traditional type crossword puzzles, consider working one (or more)
of my weekly...
 Having worked around resistors and capacitors
for more than four decades comes in handy when presented with 'simple' quizzes like
this one that appeared in a 1963 Popular Electronics dealing with
RC circuits. Still, there is always some trepidation involved when being subject,
even voluntarily, to a test of any sort, regardless of whether you are fairly confident
that it will be a lead pipe cinch, a cake walk, child's play, so to speak. Even
if nobody else will bear witness to your effort, you would feel like a real moron
if you missed even one of those simple questions that anyone with your level of
experience should get right without even having to think about it. Such is the irrational
fear I have when taking these quizzes...
 Reactance charts were a dime a dozen (free,
actually) and appeared as regular features in electronics magazines in the days
before smartphone apps provided ready access to reactance versus frequency calculations.
This one was in the May 1959 issue of Electronics World. Calculators are
nice and indispensible in design work, but sometimes having "the big picture" of
how various values of inductance and capacitance "react" with changes in applied
frequency is often useful - especially if you are a newcomer to electronics. To
paraphrase a popular saying, "A
reactance chart is worth a thousand calculators."
 This story from a 1964 issue of Electronics
magazine is close to home - literally. Well, it was close to home at the time, anyway.
It reports on the work done by the
Electromagnetic Compatibility Analysis Center "...jutting out on a pier across
the broad Severn River from the United States Naval Academy at Annapolis." I grew
up in the 1960s and 70s just a few miles from there and distinctly recall seeing
all the antennas in the area, including the now decommissioned and removed acres-big
ELF submarine communications antenna farm. The Annapolis location, with its proximity
to Washington, D.C., was the home to many government and military installations
and defense contractors. It was an electromagnetic signal-rich environment...
 Before there were
clocks that synchronized themselves to a wireless low frequency (LF) time standard
emanating from one of NIST's broadcast towers, a different method was used to keep
all the clocks in a building (like a school) reading the same time. Many of the
AC-powered mechanical master-slave clock systems are still in use today. This episode
of Carl and Jerry has them teaming with a contract repairman to figure out why seemingly
random clocks in their high school failed to synch with the master overnight. Author
John T. Frye provides a pretty thorough overview of how the system operates
using a power line carrier scheme. Of course the boys' keen troubleshooting skills...
 Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed crossword puzzle using only words from my custom-created
lexicon related to engineering, science, mathematics, chemistry, physics,
astronomy, etc. You will never find among the words names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort.
You might, however, see someone or something in the exclusion list who or that
is directly related to this puzzle's theme, such as Hedy Lamarr or the Bikini
Atoll, respectively. Enjoy!...
 The U.S. Army's Signal Corps was set up to
"exercise supervision over signal communications literally from the Pentagon to
the foxhole." Created in 1860 at the suggestion of a military doctor, the
Signal Corps originally used a system of flag waving for messaging dubbed
"wigwag" and graduated to overseeing the nationwide telegraph network six years
later. By 1870, members were tasked with establishing and operating a weather
forecasting service, so in 1907 when they created an aeronautical division it
was just in time for facilitating the nation's rapidly growing cadre of aircraft
pioneers
by providing en route weather information. Having already mastered the state...
 Even after computers became commonplace in
cubicles and laboratories, engineers and technicians kept design nomographs around
for cobbling together attenuators, filters, voltage dividers, etc. Trade and hobbyist
magazines like Electronics World used to print them as full-page features
on a regular basis, and I have posted many of them on RF Cafe over the years. This
particular "Symmetrical
T & H Attenuator Nomograph" appeared in a 1959 issue. Maybe the editor thought
that "Symmetrical T, H, O, and Pi Attenuator Nomograph" would be too long of a title
and that's why the "O" and "Pi" was omitted even though they are clearly included
in the chart. As can be seen by inspection of the circuit constructions, the
T and Pi configurations are "unbalanced" while...
 The history of electrical current is replete
with tragic incidences of maiming and death caused by ignorance and/or inattention
to known danger. Having been involved in both the electrical wiring and the electronics
fields since the 1970s, I am quite aware of the legion of hazards present when current
flows. My tool box contains screwdrivers and lineman's pliers with notches of melted
metal from inadvertent contact between differences of potential in circuit breaker
panels and electrical wall boxes. Once you experience the thrill of a sudden blinding
flash, unique buzzing sound, and smell of burning hot steel, you'll never forget
it. A
lot of people have been
electrocuted, though, through no fault...
 Pulse modulation comes in many forms, including
pulse position modulation (PPM), pulse width modulation (PWM), pulse frequency modulation
(PFM), pulse amplitude modulation (PAM), and pulse code modulation (PCM). In addition
to providing a nice introduction to the concept of pulse modulation, author Herbert
Kondo covers the basics of each type and then discusses their application in various
communications systems. The first time I recall encountering pulse modulation was
in the mid-1970s with radio control systems for model airplanes. Pulse position
modulation was the scheme used in both AM and FM sets. Modern R/C systems use frequency
hopping spread spectrum (FHSS), direct sequence spread spectrum (DSSS), or a combination
thereof...
 Less than half a decade had passed when Radio &
Television News editor Oliver Reed wrote this piece extolling the
virtues of the transistor and how "it may well revolutionize the entire
electronics industry." If you have followed a lot of my postings from the
vintage electronics magazines here on RF Cafe, you are well aware that there was
a lot of resistance to and doubt about the future of semiconductors. Naysayers
had the same kind of reaction to the advent of the horseless carriage
(automobile) and locomotive, relativity and quantum mechanics, and even curative
medicines. Point contact transistors were still largely in use, but were costly
compared to the relative simplicity and low...
 I have never seen study-at-home audio-visual
(AV) physics courses offered by Albert Einstein or AV courses on chemistry promoted
by Ernest Rutherford, but I can now say I have seen study-at-home AV courses offered
by electronics pioneer Lee de Forest. This full-page advertisement for the
de Forest's Training, Inc., company of Chicago, Illinois, appeared in a 1945
edition of Radio-Craft magazine. The vaunted (at least by the company)
"Syncro-Graphic" training was an early attempt at the paperless classroom. The
student watched films reels of instruction rather than "frequent flipping of
pages to refer back or ahead to illustrations mentioned in text." It would be
another 50 years before...
 If my counting is correct, by 1952 only 33
of America's 48 states (Hawaii and Alaska weren't admitted until 1959), and Washington,
D.C., had
television broadcasting stations. That most of the early television
experimentation occurred on the east coast is apparent by looking at the number
of stations there compared to the west coast. You might think California would
have the largest amount of TV stations, but it only had 11 located in 3 cities.
New York, on the other hand, had 13 in 7 cities. Ohio had 12 stations in 5
cities, and Pennsylvania had 7 stations in 5 cities, one of which was my town of
Erie. Vermont, New Hampshire, Mississippi, Wyoming, both Dakota, and Oregon were
among...
 By now, engineers and scientists have managed
to replace most vacuum tubes with solid state devices - at least for consumer products.
The one place tubes remain are in microwave oven. Those klystron tubes operate in
the 2.4 GHz band and typically output ranging from about 500 W to 2 kW.
No doubt materials and methods have changed since the 1950s, but fundamentally klystrons
of today are the same as klystrons then. Between this article and Part 1 that
appeared in the April 1952 issue of Radio & Television News
magazine, authors Joseph Racker and Lawrence Perenic provide a very nice
introduction on the topic. According to the Wikipedia entry, the name "klystron"... |
