Dealing with the problem of
lightning strikes was of concern long before electronic equipment needed to
be protected from its effects. Fires that were the result of lightning have always
been a problem in nature, but they were really catastrophic to civilization once
cities crowded with close-quartered wooden buildings became the norm. Benjamin Franklin
observed that when the many lightning-induced fires of Philadelphia were sparked
(pun intended), it was almost always the tallest structures in the area that were
hit. Those fire often spread to neighboring buildings and burned down entire city
blocks. It was a devastating and frequency...
"By observing
spintronic magnetic tunnel junctions in real-time, researchers found these devices
fail at unexpectedly low temperatures, offering valuable insights for improving
future electronic designs. Next-Generation Electronics Degradation A new study led
by researchers at the University of Minnesota Twin Cities is providing new insights
into how next-generation electronics, including memory components in computers,
breakdown or degrade over time. Understanding the reasons for degradation could
help improve efficiency of data storage solutions. The research is published in
ACS Nano, a peer-reviewed scientific journal and is featured on the cover..."
Arthur C. Clarke's writings and contributions
to science are vast and influential, intertwining his imaginative narratives with
profound scientific concepts. Clarke is credited with proposing the idea of
geostationary
satellites in a paper he published in the October 1945 issue of Wireless World
magazine. Titled "Extra-Terrestrial Relays: Can Rocket Stations Give Worldwide Radio
Coverage?," he described the concept of using a network of geostationary satellites
to provide global radio coverage. Geostationary satellites are satellites that orbit
the Earth at the same rate as the Earth rotates, so they appear to stay in the same
place in the sky relative to a fixed point on the Earth's surface. This makes them
ideal for telecommunications and broadcasting, as they can provide constant coverage
of a particular area without the need for multiple satellites or complicated ground
infrastructure...
Here we go with three new "What's
Your EQ?" challenges from the July 1961 issue of Radio-Electronics
magazine. Readers submit the problems, which typically involve creating a circuit
to perform a specified function, or determining how a given circuit works. The first
of these is more of a puzzle, since the author shows you how to go about arriving
at the answer. Since incandescent light bulbs are not overly familiar to a lot of
people these days, it might be to the advantage of pre-Millennials who grew up using
them and are acquainted with their properties. The second is an old-fashioned Black
Box challenge that some readers will solve without much...
"Japanese operator SoftBank announced that
the Sunglaider, its large-scale solar-powered uncrewed aircraft system (UAS) designed
for
High Altitude Platform Station (HAPS) stratospheric telecommunications, was
utilized in a field trial conducted by AeroVironment and the U.S. DoD in New Mexico,
the U.S. During the trial, carried out in early August, Sunglider succeeded in achieving
stratospheric flight, the Japanese operator said. With a wingspan of 78 meters and
the capability to carry payloads weighing up to 75kg, the Sunglider is larger than
other publicly announced HAPS UAS..."
Monday (any day, for that matter) is a good
day for Carl and Jerry stories, Mac's Electronics Service Shop sagas, Hobnobbing
with Harbaugh, electronics-themed comics, electronics quizzes, and other forms of
nerd entertainment. Here is another of Robert P. Balin's great challenges titled,
"Diagram
Quiz," this one from a 1966 issue of Popular Electronics magazine.
Most RF Cafe visitors will easily identify eight or nine of the ten diagrams. Relatively
few will be familiar with the Rieke diagram (hint: power amplifier designers will
know about it). The Biasing diagram is a bit misnamed IMHO, and could cause confusion...
Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. Three new ceramic bandpass filters have
been announced for October 2024 - a 2275 MHz center frequency filter with a
bandwidth of 250 MHz, a 2275 MHz center frequency filter with a bandwidth
of 250 MHz, and a 6245 MHz center frequency filter with a bandwidth of
360 MHz. Custom RF power filter and directional couplers designs can be designed
and produced with required connector types when a standard cannot be found, or the
requirements are such that a custom approach is necessary.
When you read this 1963 Electronics
World magazine article's title, I doubt you immediately assumed it would be
about a vacuum tube circuit, or even one that uses discrete transistors to implement
the circuit. Rather you most likely though it would be about an integrated circuit
(IC).
Operational amplifiers (opamp) are building blocks characterized (ideally) by
their infinite input impedance, zero output impedance, infinite open-loop bandwidth
and gain, zero input offset voltage, amongst other defined parameters. The first
commercially produced integrated circuit (IC) opamp came to market in 1964 via Fairchild
Semiconductor (the µA702, brainchild of Bob Widlar)...
Nickel-cadmium (NiCad) batteries have a
long and significant history in energy storage, with their invention attributed
to Swedish engineer Waldemar Jungner in 1899. Jungner's work laid the foundation
for an electrochemical power source based on nickel oxide hydroxide and cadmium,
leading to the development of the rechargeable NiCad battery. It was a pioneering
breakthrough because it represented one of the earliest forms of rechargeable energy
storage systems. This battery technology found widespread use in various industries
due to its robust performance and ability to be recharged multiple times. At its
core, the chemistry of NiCad batteries involves the reaction between cadmium (the
negative electrode) and nickel oxide hydroxide (the positive electrode), with potassium
hydroxide as the electrolyte. During...
These two
tech-themed comics from the September 1969 issue of Electronics World
magazine are pretty good. I especially like the one where the guy's wife entered
his printed circuit board layout in an art contest. PCBs were just starting to gain
momentum in production electronics as they replaced the old point-to-point wiring
method. Also popular in that era was high fidelity stereo equipment. Owning a system
with speakers that operated from 1 Hz through 30 to 40 kHz was major evidence
of an audiophile's technical savvy, even though the human ear con only detect frequencies
in the 30 Hz to 20 kHz range. Dogs can hear frequencies up into the 45 kHz
range. Porpoises can hear up to 150 kHz. A ferret can hear from 16 Hz...
TotalTemp Technologies offers advanced
and innovative methods for meeting and optimizing your thermal testing requirements.
We specialize in benchtop thermal testing because small batches are typically the
most cost-effective approach. We offer heat transfer by conduction with thermal
platforms, forced convection as in traditional temperature chambers, combined systems,
and thermal vacuum for Space Simulation.
Thermal testing of Traveling Wave Tube Amplifiers and other devices with dramatically
uneven power dissipation can easily be achieved with a dual zone thermal platform.
Managing the heat produced by the electron gun side allows for the RF outputs side
to be tested at various required temperatures. The Dual Zone Thermal Platforms allows
the user to maintain safe controlling...
• Ham
Radio Serving Southeast U.S. Recovery Efforts
• Radio
"A Godsend for So Many" in Helene's Aftermath
• Estate
Planning for Hams
• Intel's Woes Damaging
U.S. Chip Indpendence
• Is
Gen-Z Low Car Ownership a Threat to Radio? (they
can't afford cars due to massive inflation - not because they don't want a car)
Amrad, American Radio & Research Corporation,
was based in Medford Hillside, Massachusetts and was founded in 1915 with funds
from J. Pierpont Morgan. The company's first manager, Harold James Power, was an
amateur radio enthusiast and built a research laboratory. In 1916, Amrad made its
first broadcast to J. Pierpont Morgan Jr., who was aboard the ocean liner "Philadelphia."
Amrad received orders for military radio equipment during World War I, but discontinued
these orders after the war ended. To keep the company afloat, Amrad produced items
such as electric egg beaters and cigar lighters. In 1919, Amrad was awarded a contract
to make 400 SE1420 receivers, and it began advertising components for amateur radio
enthusiasts...
This "Which
Dry Battery for You" article is a follow-on from the previous month's "Dry Cell
Battery Types" in Radio-Electronics magazine. It was a time long before the dominance
of rechargeable lithium batteries. In 1963, battery-powered devices were nowhere
near as widespread and diverse as they are nowadays. Hand tools like drills, saws,
routers, planers, and screwdrivers got their power either from a wall outlet or
the user's arm and hand muscles. Lawn mowers, grass and hedge trimmers, chain saws,
and snow blowers were powered mostly by gasoline, although some models plugged into
the wall. Those devices which did use batteries most often had no built-in...
"Researchers have developed a new architecture
for optical computing called
diffraction casting, offering power-efficient processing by using light waves.
This method promises better integration and flexibility for high-performance computing
tasks and could be used in fields like AI and machine learning. As artificial intelligence
and other complex applications demand ever more powerful and energy-intensive computers,
optical computing emerges as a promising solution to enhance speed and power efficiency.
However, its practical application has faced numerous challenges..."
The Atomic Energy Commission (AEC) was established
in 1946 as a result of the Atomic Energy Act, signed into law by President Harry
S. Truman. This legislative decision marked the United States' formal entry into
managing and controlling atomic energy, a rapidly advancing field that had been
essential in concluding World War II through the development and use of nuclear
weapons. The AEC was conceived to handle not only military applications of atomic
energy but also to develop peaceful uses, such as energy production, medical research,
and industrial applications. The creation of the AEC emerged from the Manhattan
Project, the secret wartime effort to develop atomic bombs. The Manhattan Project
brought together prominent scientists like J. Robert Oppenheimer, Enrico Fermi,
and Niels Bohr. After the war, however, the question arose...
Empower RF Systems, the technology leading
provider of high-performance RF amplifiers, is proud to announce the launch of the
Model 2221 X-Band Pulsed High Power Amplifier. The Empower RF 2221 amplifier
operates in the 9-10 GHz X-band, delivering an impressive 8000 W peak
output power with long and short pulse widths. Its applications encompass radar
systems, electronic warfare, HPM research, and electromagnetics effects testing.
With a rugged, modular design, the 2221 offers a reliable, high-performance solution
for applications demanding significant X-band power. Key Features and Specifications
The model 2221 amplifier operates in the 9-10 GHz X-band frequency range, delivering
an impressive 8 kW of peak pulsed output power...
Although not in the title as it used to
be, this 1964 Electronics World magazine piece by John T. Frye is
a "Mac's
Service Shop" story. If Mac and Barney are the stars of the saga, then it can
be none other. The story is about how the misdeeds of a few dishonest operators
can taint the reputation of an entire industry - nothing new there. Barney is telling
Mac about a "sting" ploy pulled by a consumer protection group whereby TV sets with
a specific easy-to-troubleshoot problem introduced to see how repair technicians
from a suspect company would bill the service. I'll not spoil the ending for you;
however, a comment mentioned that $10 would have been a reasonable price for a house
call that included the fix. According to the BLS's inflation calculator, $10 in
1964 was the equivalent of about $102 in 2024...
Ever the futurist, in 1962 Radio-Electronics
magazine editor Hugo Gernsback was making the case for occupying
millimeter- and submillimeter-wave bands. In fact, he first proposed the concept
back in 1959. He refers to it as "gap between the infrared (IR) and radio regions."
IR is generally understood to include wavelengths from around 750 nm (400 THz)
to 1 mm (300 GHz). Gernsback cites work done by Professor Gwyn O. Jones,
of Queen Mary College of the University of London, with the claim that among other
advantages of millimeter-wave (mm-wave) is an ability to penetrate certain wavelength
"windows" in the atmosphere where lower frequencies do not propagate efficiently,
more "channels" of communications can be accommodated, smaller antennas could be
used, and narrower focused transmission beams possible...
Werbel Microwave's WMRD10-7.2-S is a
10-way resistive splitter that covers up to 7.2 GHz with ultra-wide bandwidth.
This unique design accomplishes extremely flat frequency response in a small radial
package. Our unique design approach provides higher than expected isolation between
outputs at far ports than would be achieved in a typical star topology. It has applications
in markets such as CATV, test and measurement, and military radio. Its small size
makes it easy to integrate into compact systems. Designed, assembled, and tested
in the USA.
Hugo Gernsback, often heralded as the "Father
of Science Fiction," was an extraordinary figure whose influence extended beyond
the realm of speculative literature into the world of electronics, radio communication,
and futurism. His life, inventions, and publications shaped not only popular science
but also the practical development of radio and electronics, making him a pivotal
figure in early 20th-century technological advancements. Gernsback was born Hugo
Gernsbacher on August 16, 1884, in Luxembourg City, Luxembourg, to a wealthy family.
His father, Moritz Gernsbacher, was a winemaker and merchant, while his mother,
Bertha, came from a prominent local family. Hugo had several siblings, though details
of his early family life remain somewhat obscure. From a young age, Hugo showed
a strong interest in science and technology, particularly in electricity and wireless
communication. He attended local schools in Luxembourg and later pursued formal
education at the Technikum in Bingen, Germany...
These government programs take forever to
implement, then a major portion of the money gets wasted in bureaucracies, payoffs,
and misappropriations (e.g.,
8 EV charging stations after spending $7.5B). "If you know CostQuest at all
you probably think of it as the company that the FCC hired to clean up and refine
its national broadband map. But the company is also working with state broadband
offices on their
Broadband Equity, Access and Deployment (BEAD) programs. To give a little background,
CostQuest works with the FCC on its national broadband map. But it was also hired,
separately, by the National Telecommunications and Information Administration (NTIA)
to work with states..."
The
Radio Corporation of America (RCA) holds a significant place in the history
of American technology and business. Founded in 1919, RCA was initially created
as a government-sanctioned monopoly to manage the United States' growing interest
in wireless communication. During its peak, RCA was a dominant player across multiple
industries, including consumer electronics, communications, broadcasting, and defense
technology. Its influence extended through radio, television, radar, semiconductors,
and beyond. The inception of RCA was rooted in the growing importance of wireless
communication during and after World War I. The company was established by General
Electric (GE), which was pressured by the U.S. government to create a new entity
that would ensure...
When this was originally posted it was the
beginning of the IEEE's 2007
Microwave Theory and Techniques Society's (MTT-S) International Microwave Symposium
(IMS) in Honolulu, Hawaii. This advertisement from the January 1969 issue of Electronics
World magazine promoted Institute of Electrical and Electronics Engineers (IEEE)
annual symposium. Per the MTT.org website, the very first IMS show was held in 1995,
in Orlando, Florida. The 1969 IEEE International Convention & Exhibition, which
was not specifically a microwave electronics theme, was held in the New York Coliseum,
located in New York City...
If you have been wanting access to
nitrous oxide (N2O), aka laughing gas, in order to "encourage" someone
to divulge subconscious (or intentionally suppressed) information, but don't want
to pay the high cost of storage bottles and refilling, then here are instructions
in a 1949 issue of Popular Science magazine for brewing some on your own.
Purchase of N2O is legal, and is used, among other things, as an engine supercharger
which is injected into the intake manifold. I had a friend back in the 1970s with
such a system installed on his 1968 Camaro that had a 454 cu. in. big
block in it. It could easily pop the front wheels off the ground. Dentists and doctors
still use it as an anesthetic, food products like whipped cream...
The evolution of
Crosley
radio products is a fascinating journey through the golden age of radio, a period
marked by significant technological advancements and changing consumer preferences.
Powel Crosley Jr.'s genius lay in his ability to combine affordability with cutting-edge
features, making his radios highly desirable for the average American household.
Crosley Radio Corporation's products evolved rapidly, reflecting the company's commitment
to innovation and its response to market demands. Crosley's radio journey began
in 1921 when he created the Harko, an affordable crystal set that was small and
compact enough to sit on a tabletop. Early radios at the time were relatively...
It is amazing how some substrate layouts
look exactly like a block diagram of circuit they represent. "With increasing data
rates in mobile communications, the need for more powerful high-frequency electronics
is growing. This is particularly true for satellite-based global communication networks,
which must function reliably and securely in all weather conditions and at any location.
In the ESA Magellan project, researchers at Fraunhofer IAF, together with UMS and
TESAT, are therefore developing novel efficient
GaN transistors and high-power amplifiers for LEO and GEO communication satellites
to provide high..."
Allen B. DuMont, a pivotal figure in the
early days of television and electronics, was born on January 29, 1901, in Brooklyn,
New York. His contributions to the advancement of television technology, particularly
through his work on cathode-ray tubes, and the founding of the DuMont Television
Network, left a lasting mark on the broadcasting industry. DuMont's early years
were marked by adversity. As a young boy, he contracted polio, which left him bedridden
for several months. Despite the physical limitations imposed by the disease, DuMont's
intellectual curiosity flourished, and he turned to reading and tinkering with electronics
to occupy his time. This early exposure to electrical engineering would shape his
future. DuMont's passion for electronics was evident from an early age. By the time
he was a teenager, he had built his own radio receiver. He attended Rensselaer Polytechnic
Institute (RPI)...
Ever heard of "sferics?" That's a new word
in my technical lexicon as of right now. Sferics (aka spherics), is a contraction,
derived from "atmospheric" phenomena, specifically referring to the electromagnetic
signals generated by natural events in the atmosphere, such as lightning discharges.
Over time, its use has become specialized in the field of meteorology, physics,
and certain branches of electrical engineering, where it is used to describe specific
types of electromagnetic emissions. It was mentioned in this "News
Briefs" column in a 1961 issue of Radio Electronics magazine. Also
in the news was the decreasing conductivity of the atmosphere due to low sunspot
activity. Ham DX'ers love sunspots since by charging the upper atmosphere, it facilitates
long distance communications. Japanese color TV sets were deemed "impressive." Much
more...
"Recent advancements in
phonon laser technology, which utilizes sound waves rather than light, show
promising new applications in medical imaging and deep-sea exploration. A novel
technique enhances these lasers by stabilizing and strengthening the sound waves,
allowing for more precise and powerful outputs. This development not only improves
existing uses in medical and underwater applications but also extends potential
uses to material science and quantum computing. Scientists in China have made a
significant leap in developing lasers that use sound waves instead of light. These
'phonon lasers' hold promise for advancements in medical..."
Powel Crosley Jr., an American inventor,
entrepreneur, and industrialist, was born on September 18, 1886, in Cincinnati,
Ohio. He became one of the most prolific figures in American industry, with contributions
spanning from radios to cars, and from kitchen appliances to television broadcasting.
His innovative spirit, coupled with a keen business sense, enabled him to leave
an indelible mark on American consumer culture during the first half of the 20th
century. Crosley's early years were shaped by a supportive, middle-class family.
His father, Powel Crosley Sr., was a successful attorney, which afforded young Powel
and his siblings a comfortable upbringing. Crosley was drawn to mechanical and electrical
engineering from an early age, demonstrating an innate talent for tinkering. As
a boy, he built his own working model of a car...
"In these modern times, electronic systems
are usually operating within an
electromagnetic-interference (EMI) environment that contains many other electronic
systems. These systems need to exist and fully operate undisturbed while meeting
electromagnetic compatibility (EMC). EMC requirements are separated into two main
parts: Electromagnetic immunity - a system must not be disturbed by any other systems.
The electromagnetic interference in a system can't disturb any other system. Then,
if immunity and emission requirements are individually met, the electronic product,
such as an integrated circuit (IC), may be marketed from an EMC point of view. Measurement
methods for EMI and electromagnetic emission (EME) are fully described for ICs in
the IEC62132-4 (immunity) and IEC61967-4 (emission)..."
The
Space Race was one of the most significant geopolitical and scientific competitions
of the 20th century, driven by the rivalry between the United States and the Soviet
Union during the Cold War. It spanned from the late 1940s through the 1970s, with
a focus on achieving superiority in space exploration, a domain viewed as critical
not only for scientific advancement but also for military and strategic dominance.
Rooted in rocket technology developed during World War II, the Space Race transformed
the world's understanding of science and technology, culminating in the most dramatic
achievement: the landing of humans on the Moon in 1969. This treatise explores the
key milestones, the countries and key players involved, technological developments,
the interplay between military...
|
For some inexplicable reason I went backwards
on this three-part
Tube Family Tree series that appeared in Popular Electronics. Author
Louis Garner, Jr., starts out with the early history of vacuum tubes, beginning
with Thomas Edison's incandescent light bulb and then quickly progresses to Lee
de Forest's Audion amplifier tube, and on through the evolution of multi-grid vacuum
tubes that are specially designed for low noise receiver front ends, high power
transmitters, voltage and current regulators, video cameras, pulse forming networks,
traveling wave tubes, and many other types. There is quite a bit of information
and history contained in these three installments that will do a very nice job of
introducing you to the wonder... Here you can read
Part 1,
Part 2 and
Part 3
This story was posted sometime around 2009.
Since that time, research has been conducted by members of the
Harvard Wireless Club
regarding the veracity of the claim. RF Cafe visitor Fred Hopengarten, Esq. (K1VR),
wrote to apprise me of the situation. It concludes as follows: "Back in 1999, the
late K3UOC, who received his Ed.D. from the Harvard Graduate School of Education
and was very active with our club, wrote: Note: This legend has been published and
told by word-of-mouth countless times over the past 90 years. Unfortunately, it
isn't so. HWC members researched this story, even obtaining the copy of the Congressional
Record for the date in question. We could find no record of Mr. Hyman appearing
before congress. We have to admit, though, it's a very entertaining story!"
This "Recent Developments in Electronics"
from a 1960 issue of Electronics World had a lot of
antenna news that included a retarded surface wave antenna with high gain and
low silhouette for use in airborne early warning radar as well as ground based and
shipboard radar, a pair of 60-foot tropospheric scatter antennas that are specially
mounted at opposite ends of a 180-mile long section of the Gulf of Mexico, and a
104-foot-long rotating 50-ton radar antenna used for the SAGE early warning system.
Also reported was Westinghouse Electric's airborne Stratovision for broadcasting
educational television programming to rural areas out of reach of existing
towers...
It's probably a safe bet that most people,
even at the
dawn of color television, knew of the competition which occurred for the adoption
of three different methods of implementation. Two of them - line-sequential by Color
Television, Inc. (CTI), and dot-sequential by Radio Corporation of America (RCA)
- were fully electronic while the third system by the Columbia Broadcast System
(CBS) used a kludge of a spinning color wheel placed in front of a black and white
display. The CBS field-sequential design used a synchronization component of the
composite transmitted signal to position the correct color screen (red, yellow,
or blue) in front of the screen as the electron gun scanned the CRT - analogous
to how World War I airplane machine guns were synchronized with the engine
to fire between propeller blades. Of course an out-of-synch scenario in the color
wheel was not as serious as with the machine gun. The worst that could happen with
the TV is a false color picture whereas with the machine gun your biplane instantly
became a glider. Although I poke some fun at the CBS solution...
Acrylic wall-to-wall carpeting really came
into vogue in the late 1960s to early 1970s - just in time for the arrival of miniaturized
microelectronics (is that redundant or just superfluous?). Gate widths were being
shrunken rapidly as the birth of the Moore's Law era was in its infancy (born in
a 1965 paper written by Intel engineer and co-founder Gordon Moore). The result
was copious quantities of
electronic gadgets being zapped when the unsuspecting user would walk across
the Van de Graaff generator in the form of floor covering and reach for a dial or
switch. A couple thousand volts could easily build up on a body clad in lime green
polyester pants (remember the era), then fzzzzt, there goes the clock radio or AM/FM
tuner. Vacuum tube circuits from a decade earlier ...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers"
Smith chart design. These would make excellent gifts for husbands, wives, kids,
significant others, and for handing out at company events or as rewards for excellent
service. My graphic has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. I only make a couple bucks
on each sale - the rest goes to Cafe Press. It's a great way to help support RF
Cafe. Thanks...
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 225,000 times per year! New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company
news to be seen, RF Cafe is the place to be...
If you think science-challenged politicians grandstanding
in the media to gain - ostensibly, but unfortunately likely - favor with their constituents
is a new phenomenon, take a look at this. On almost a daily basis these days we have
elected doofuses pretending to be experts in physics, climatology,
chemistry, medicine, economics, and other realms of learned science, when all
they are really are mouthpieces for special interest lobbyists whose clients
have lots of money for elections. At the risk of being too repetitive, I have to
point out the brilliant congressman from Georgia who thought that the...
This is the
electronics market prediction for Sweden, circa 1966. It was part of a comprehensive
assessment by the editors of Electronics magazine of the state of commercial, military,
and consumer electronics at the end of 1965. Among Sweden's modern-day most recognizable
electronics and related manufacturers are Ericsson, Saab Group and Electrolux, in
existence in one form or another since 1965. Automotive company Volvo is also among
the largest manufacturers there, although not specifically of electronics. A number
of contemporary resources are available for obtaining reports (at a cost) on the
electronics industry in almost every country on Earth. Among them are "Consumer
Electronics in Sweden, August 2019" and "Electronics Industry in Sweden June 2019..."
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
The
electromagnetic world sure is a noisy place and it is getting worse all the time
- in every region of the spectrum. Intentional radiation is not so much of a problem
because it usually falls within well-defined limits and is predictable, but sloppy
engineering and, honestly, ignorance, has made life harder for just about everyone.
Listeners to broadcast radio in both the
AM and FM bands
have really taken a hit. AM has always been prone to interference by its very nature,
so anyone listening expects the occasional pop or hiss from atmospheric phenomena
or a light switch being flipped on or off. Have someone in the house run a blender
or drill and you can forget hearing anything until the task is completed. It comes
with the territory, so to speak. FM was and is largely immune to most forms of interference,
but lately I have been noticing it coming from some of the most unusual places.
For as long as I can remember, I have preferred to have a radio on in the background
whilst whiling away at work and at play...
Interestingly, the February 1958 article
in Radio & TV News magazine entitled "Report
on the Soviet Earth Satellite" never mentions the craft's name - "Sputnik 1,"
or "Простейший Спутник-1," which in English is "Elementary Satellite 1." Sputnik 1
was, in case your history is a bit fuzzy, the world's first successful artificial
communications satellite. Launched by the Union of Soviet Socialist Republics (USSR)
on October 4, 1957, Sputnik 1 remained operational for about three weeks in
low Earth orbit (284 miles average), during which time radio receiving stations
across the globe anxious tuned in hoping to hear the 20.005 MHz and 40.002 MHz
pulses that alternately repeated continuously in an alternating manner - the first
FSK (frequency-shift keying) from space. Ruskie engineers made the signal frequencies
and periods as stable as possible in order to enable careful frequency and timing...
All RF Cafe quizzes would make perfect fodder
in employment interviews for technicians or engineers - particularly those who are
fresh out of school or are relatively new to the work world. Come to think of it,
they would make equally excellent study material for the same persons who are going
to be interviewed for a job. This particular quiz challenges your knowledge of
radar fundamentals. Do you know what a
"radar mile" is? Bon chance.
Admittedly, with all the reading I have done
of vintage electronics magazines, news of this
Crystron (crystal-electron) vacuum tube device invented by Mr. Mohammed
Ulysses Fips, as reported in the April 1947 issue of Radio Craft magazine,
evaded my attention. The article came only a couple months after publication of
the 40th anniversary edition that celebrated Dr. Lee de Forest's invention
of the Audion tube. According to Mr. Fips, his Crystron one-upped the Audion
by virtue of its containing a small amount of radio isotope which obviated the need
for the traditional "B-battery" concept also developed by de Forest to supply
a high voltage for driving the output stage circuit. While not capable of powering
a concert hall audio speaker system, it did make possible use of a small speaker
as a nearby personal listening device rather than requiring headphones or earbuds.
Without divulging the most critical and closely-held details of the Crystron as
the U.S. Patent Office...
Working crossword puzzles can be contagious.
This April 12, 2020,
tech-themed crossword puzzle may even go viral - the second in a series. It
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have personally built over nearly two decades.
That includes the cause for our planet's current dilemma. Many new words and company
names have been added that had not even been created when I started in the year
2002. You will never find a word taxing your knowledge of a numbnut soap opera star
or the name of some obscure village in the Andes mountains. You might, however,
encounter the name of a movie star like Hedy Lamarr or a geographical location like
Tunguska, Russia...
As with my hundreds of previous
science and engineering-themed crossword puzzles, this one for February 2, 2020,
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have built up over nearly two decades. Many
new words and company names have been added that had not even been created when
I started in the year 2002. You will never find a word taxing your knowledge of
a numbnut soap opera star or the name of some obscure village in the Andes mountains.
You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical
location like Tunguska, Russia, for reasons which, if you don't already know, might
surprise you...
Do you remember back in the 1980s when adoption
of the IEEE-type logic schematic symbols* got a big push? It proposed a logical
approach (pun intended) to building any type of combinational logic or sequential
logic devices based on strict rules of construction. Curved lines are nowhere in
sight. Interestingly, the same type of schematic symbol "simplification" was proposed
in the 1940s. The motivation for removing curved lines was to prevent draftsmen
from needing to use a compass or special drawing template rather than using only
a straight edge. Vacuum tube outlines, light bulbs, inductors, etc., required more
time to pencil in. In 1944, this article entitled "Are
Radio Symbols Wrong?" appeared in Radio-Craft magazine...
Syzygy is a great word for a Scrabble game.
If you use it on a Triple Word Score (TWS) space where the "Z" sits on a Double
Letter Score (DLS) space, it will net you 105 points. About the only way to do better
is to use all 7 letters on a TWS play, where you earn 50 bonus points added to your
word score (I've done it twice in the last year).
Syzygy is an astronomical term referring to an alignment of three or more celestial
bodies - not necessarily in exact alignment, but within a few degrees. Astrologers
(not to be confused with astronomers) have since their knuckles no longer dragged
on the ground exploited such scenarios to predict various events both good and bad.
That was even before they knew those "wandering" orbs (planet means "wanderer")
were different than the (seemingly) stationary points of light. Until Galileo turned
his rudimentary telescope on the planets, the only celestial objects with a discernable
disk shape were the sun and moon, and possibly the earth. But I digress. It was
long thought that the vector sum of gravitational influences was responsible for
certain phenomena on our planet, including weather, tides, and earthquakes...
Ode on a Power Supply? Well, maybe not really
an ode, but this poem entitled, "Power Supply," written by Eileen V. Corridan,
appeared in the September 1942 edition of the ARRL's QST magazine. It is
really quite entertaining and instructive! It applies to the original tube-based
circuit as well as to modern solid state versions. I somehow get the feeling that
this poem will now be republished in many places...
Amateur radio enthusiasts are very familiar
with
burying ground radials below the surface (or sometimes just laid on top) in
order to increase antenna efficiency by affecting impedance and, more importantly,
the radiation pattern. Long distance (DX) operators generally prefer low launch
angles over high angle "cloud warmers." Pittsburgh's KDKA, the country's first commercial
broadcast radio station, built what would have been the mother of all ground radial
arrays for its time - 360 (one every degree), 700-foot copper wires (8 AWG), for
a total of a quarter million feet! It was laid using a farm tractor drawing a non-motorized
trench cutter that looks like it came straight from the John Deere factory. It also
implemented a new type of passive vertical suppressor element array...
At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (1/15 - 1/19)
"Tech Industry Headlines" column on the RF Cafe homepage (see
the Headline Archives page for help). For the sake of all the avid cruciverbalists
amongst us, each week I create a new technology-themed crossword puzzle using only words
from my custom-created related to engineering, science, mathematics, chemistry, physics,
astronomy, etc. Enjoy!...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
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 contacts with
the germanium PN base substrate, commercially viable bipolar transistors use a doping
element diffused into the purified crystal substrate to effect the emitter, base,
and collector regions on a single crystal (with gold contact pads for attaching
external leads)...
It is important to concentrate your transmitter
power into the proper beam if you wish to deliver the best signal to the other fellow's
receiving antenna. This has logically led to the popularity of the Yagi beam antenna
on the higher-frequency amateur bands. A beam antenna for the 80-meter band should
have a 140-foot reflector and a 77-foot boom on a 250-foot tower. This makes the
beam antenna impractical for the 80-meter band, and even for 40-meter operation
a full-size Yagi is a forbidding structure to the neighbor's narrow-minded view
- even a well-trained XYL might view such a monster beam with alarm. There is no
easy solution to the need for a good DX antenna at low frequency, but the conical
monopole antenna may be of interest to the more eager radio amateur as a more practical
solution. The
conical monopole antenna is a base-fed vertical antenna that has an omni-directional
pattern in azimuth but with an elevation...
This is yet another example of humorous -
and clever - poetry written by Hams from back in the 1940s... November 1942, to
be exact. It appeared in the ARRL magazine QST. As alluded to in the title,
"Ravin," it is a play
on Edgar Allen Poe's famous "The Raven" poem. A few other electronic-themed poems
are listed on the page as well, discovered in QST and in Popular Electronics.
Enjoy...
Audio crossover networks have the same fundamental
mission as RF multiplexer filters in radio systems, which is to separate and steer
specific bands of frequencies into two or more signal paths. While simple in concept,
implementation in hardware can be a major challenge depending on requirements for
channel separation, feedthrough, phase and group delay, amplitude equalization,
distortion, and other factors. This article discusses some of the decisions used
by crossover network designers when considering where to make band breaks, while
leaving actual circuit design rules to other authors. I built a set of custom speakers
many moons ago and went through the frustrating process of deciding where to place
the breaks and which speakers to use...
As radio equipment builders and operators,
we still battle two fundamental issues that have been around since the beginning
of time (well, from Marconi's time, anyway) -
grounding and power supply fluxuations. Both topics are addressed briefly here
in this editorial column from a 1932 The Wireless World magazine. Back
in the day, grounding was referred to as "earthing," and was/is essential to
optimal wireless and wired performance. Line voltage fluxuations are generally
much less severe today than in the 1930s thanks to better transformers,
automated monitoring and adjusting of line voltages, and better distribution
designs. The worst type of power line fluxuation - a lightning-induced surge -
has been greatly reduced thanks to superior engineering, primarily by the simple
running of a grounded neutral "static" wire running at the top of all the lines
below it on utility poles and transmission towers...
"Technically,
panoramic reception is defined as the simultaneous visual
reception of a multiplicity of radio signals over a broad band of frequencies.
In addition, panoramic reception provides an indication of the frequency, type
and strength of signals picked up by the receiver. Deflections or 'peaks'
appearing as inverted 'V's on the screen of a cathode-ray tube." It is the kind
of display that radar operators at Pearl Harbor were using when they mistook
wave of incoming Japanese bombers a squadron of B-17s from the mainland. The
panoramic receiver is not a wartime development, experimental models having been
produced just prior to the outbreak of war. However, the many uses to which it
has been put have demonstrated that the panoramic idea, particularly in the form
of adaptors which may be connected to any receiver, is going to be very
important...
This is another installment of the "Hams
in Combat" series that the ARRL's QST magazine ran during WWII. I enjoy
vicariously waxing nostalgic of a time before I was born, at time when there was
still honor, courage, selflessness, and pride of country. During World War II, it
was an ingrained part of most citizens, whether or not they happened to be serving
in the military. Our modern day troops still have it, but sadly fewer and fewer
people see their own country as any place special in the world. Many don't believe
it ever was. Sure, as General William Tecumseh Sherman famously said, "War is hell,"
but then again so is witnessing the tearing apart of your country from forces within...
Take a
break from the drudgery with some of these
tech-centric jokes, song parodies,
anecdotes and assorted humor that has been collected from friends & from websites
across the Internet. This humor is light-hearted and sometimes slightly offensive
to the easily-offended, so you are forewarned. I have taken care to censor out "humor"
with reproductive function innuendo and hateful tirades, so it is all workplace-safe.
I have also tried to warn of any links that will result in audio clips so you can
take appropriate precautions. As usual, there is no easy way to determine the true
origin of any of these jokes. Unless otherwise noted, that prolific author "Anon"
is the progenitor...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols... |