See Page 1 | 2 of the November 2024 homepage
archives.
Monday the 14th
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)...
Friday the 11th
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...
Thursday the 10th
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...
Wednesday the 9th
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...
Tuesday the 8th
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)...
Monday the 7th
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...
Anatech Electronics (AEI) manufactures and
supplies RF and microwave
filters for military and commercial communication systems, providing standard
LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard
RF filter and cable assembly products are published in our website database for
ease of procurement. Custom RF filters designs are used when a standard cannot be
found, or the requirements dictate a custom approach for your military and commercial
communications needs. Sam Benzacar's monthly newsletters address contemporary wireless
subjects. Please visit Anatech today to see how they can help your project succeed.
Friday the 4th
Yay, Friday is here at last! To help you
wind down the week, take a gander at these four
electronics-themed comics which appeared in a 1961 issue of Radio-Electronics
magazine. The one on page 106 is my favorite. It reminds me of an old Bugs Bunny
cartoon from back in the 1970s, where a freeway was going to built over his rabbit
hole (warren), and Bugs thwarted all efforts by construction crews from violating
his humble abode (see "No Parking Hare"). There was another similar episode where
skyscrapers were built around his hole, but I cannot find it. The page 95 comic
reflects the public's fascination with rocket flights in an era when the first satellites
were being launched, and manned spaceflight filled the imaginations of young and
old. By coincidence, today's (October 4th) RF Cafe header logo features the
Sputnik launch...
"Iridium Communications Inc., a leader in
global voice and data satellite communications, has taken a significant step forward
in its mission to enhance connectivity. The 3rd Generation Partnership Project (3GPP)
has officially accepted Iridium's request to expand the functionality of
Narrowband Internet of Things (NB-IoT) for Non-Terrestrial Networks (NTN) into
the Work Plan for 3GPP Release 19. This marks a pivotal moment for Iridium's upcoming
service, Iridium NTN Direct?, which aims to provide unprecedented access to satellite
services via standard chipsets. What is Iridium NTN Direct?...
The Space Race was at its peak in 1964 when
this advertisement by the
Capitol Radio Engineering Institute (CREI) Program in Space Electronics appeared
in Electronics World magazine. Although it all began in 1957 with the International
Geophysical Year, the heat was turned up that year when the USSR successfully launched
Sputnik 1, the world's first artificial satellite. President John F. Kennedy
made his famous speech before the U.S. Congress in 1961, where he said in part,
"This nation should commit itself to achieving the goal, before the decade is out,
of landing a man on the moon and returning him safely to the earth." A huge push
was made by colleges...
• Solar Cycle 25 Producing
Record High Sunspot Numbers
•
34% Huawei Revenue Hike for 1st Half Year
• Layoff
Survival Guide for These Tough Times
• Rumors of
Samsung Acquiring Nokia Fly
•
Supply Chain Sustainability's Future
The early 1960s was an era of significant
change for the realm of in-home entertainment. Television was transitioning to color,
radio was transitioning from AM to FM, and FM radio was transitioning from monaural
to stereo. Print media was beginning to include more color in its pages. The human
sense organs and brain were being called upon to process much more information from
sources other than real-world experience. For many people, seeing the world's natural
and manmade features in color was an amazing revelation, and our household was one
of last in the neighborhood to get a color TV. My introduction to stereophonic music
does not have as much of a stark place in memory. Prior to high school, my radio
listening was AM station WNAV...
Thursday the 3rd
The
International Geophysical Year (IGY) was an extraordinary scientific endeavor,
representing a global cooperative effort to study Earth's physical properties and
atmosphere. Spanning from July 1, 1957, to December 31, 1958, the IGY was timed
to coincide with a period of maximum solar activity, a factor which was thought
to significantly influence Earth's environment. The project brought together scientists
from 67 countries, transcending Cold War tensions, with the goal of advancing our
understanding of the Earth and space sciences. This extensive treatise delves into
the various aspects of this monumental event, including the research conducted,
the countries involved, key figures, industrial partnerships, the science of rockets
and satellite...
"Physicists present a
nanometer-sized light antenna with electrically modulated surface properties
- a breakthrough that could pave the way for faster computer chips. Advances in
plasmonic resonators could lead to computer chips that are up to 1000 times faster,
thanks to collaborative efforts between German and Danish universities. These teams
have successfully modulated light antennas electrically and integrated quantum mechanics
into classical physics models, promising profound technological impacts. Today's
computers reach their physical limits when it comes to speed. Semiconductor components
usually operate at a maximum usable frequency of a few gigahertz..."
Raise your hand if your old stereo system
had a "Loudness"
control, but you never really knew what it did - other than change the loudness
(my hand is up). Author Rudolph Jacobs addresses the subject in a technical manner
- Fletcher-Munson curves and all - in this 1963 edition of Electronics World
magazine. In a nutshell, in case you don't feel like reading the entire article,
Loudness compensates for the difference in perceived sound intensity level across
the audio frequency spectrum as the reference level is varied. That is to say, it
maintains the same perceived listening level across the audio spectrum whether you
have the volume control turned way down, way up, or in the middle - a sort of volume-dependent
equalizer.
Transcat | Axiom Test Equipment, an electronic
test equipment rental and sales company has published a new blog post entitled "Grid
Simulators Are Smart Power Sources" that covers how to pick the right grid simulator
that best fits the needs of your project requirements. Choosing a grid simulator
for an application is a matter of understanding available functions and key operating
parameters, such as voltage, current, power, and output frequency. Grid simulators
supply AC and DC electrical power under the many conditions exhibited on an electrical
power grid and can accurately measure bidirectional power from DUTs or loads capable
of generating power. A regenerative grid simulator can manage fully four-quadrant
electrical power while returning a high percentage of power to the grid for testing
under "green" energy operating conditions...
The
tech-themed comic that appeared on page 59 of the February 1969 issue of
Electronics World magazine is consistent with the prevailing theme of the era
where wives and girlfriends were fairly oblivious to the meaning of technical endeavors
of their husbands and boyfriends, respectively (or not necessarily). The other comic
from that edition is reflective of the times as well, when a television was considered
to be one of the essentials of modern life. Carrying one's essentials wrapped up
in a cloth and tied to the end of a wooden pole represented the stereotypical kid
running away from home. I was a pretty rotten kid, but I don't remember ever running
away from home - probably because I knew that my parents knew that I knew...
Wednesday the 2nd
This could be one of those quizzes where
common items are shown close-up so they do not look familiar, and the reader's job
is to figure out what he's seeing. The montage of micrographs of antimony, cadmium
sulfide, germanium etched in argon, and germanium etched in hydrogen, appeared in
a 1962 issue of Radio-Electronics magazine. All are elements / compounds
currently (at the time and now) being researched and used in semiconductors. Knowledge
of
semiconductor physics has multiplied exponentially in the succeeding six decades
(hard to believe that much time has passed). The Massachusetts Institute of Technology's
(MIT) Lincoln Laboratory did the work shown here...
Like most people familiar with electronics,
when
negative resistance semiconductors are mentioned, I immediately think of tunnel
diodes. Negative resistance is the characteristic where in increase in voltage across
the p-n junctions results an a decreased current. Although the tunnel diode was
invented by by Leo Esaki (Sony) in 1957, it is not mentioned anywhere in this 1969
article. Instead author Wesley Vincent (Motorola) describes the theoretical operation
of 4-layer (3 junction) semiconductors and how they can be biased to mimic true
negative resistance devices. Given that one of the most common applications of tunnel
diodes is to construct relaxation oscillators, knowing which configurations of standard
BJTs can act like...
"Researchers have developed a method to
create a
two-dimensional silk protein layer on graphene, enhancing its potential in microelectronics,
particularly for wearable and implantable health sensors and memory transistors
in computing. This innovation offers a nontoxic, water-based, and biocompatible
system, potentially revolutionizing silk's application in luxury materials and high-tech
industries. The research opens pathways for further advancements in silk-integrated
circuits and sustainable electronic solutions. After thousands of years as a highly
valuable commodity, silk continues to surprise. Now it may help usher in a whole
new direction for microelectronics and computing..."
This 1935 article found in Short Wave
Craft magazine quotes the
DJC radio station engineer as saying that they transmitted with
only 5 kW into the farm of directional antenna arrays, and that it was sufficient
to provide what was evidently very high quality reception to many remote regions
of the world. Adolph Hitler had become "Führer und Reichskanzler" the year before,
with plans already in the works to dominate the world. Troops invaded Poland on
September 1, 1939, officially beginning WWII. DJC's global reach was used extensively
for propaganda during the war...
Axiom Test Equipment, a Transcat company,
allows you to rent or
buy
test equipment, repair
test equipment, or
sell or trade test equipment. They are committed to providing superior customer
service and high quality electronic test equipment. Axiom offers customers several
practical, efficient, and cost effective solutions for their projects' TE needs
and is committed to providing superior customer service and high quality electronic
test equipment. For anyone seeking a way to offload surplus or obsolete equipment,
they offer a trade-in program or they will buy the equipment from you. Some vintage
items are available fully calibrated. Please check out Axiom Test Equipment today
- and don't miss the blog articles!
Tuesday the 1st
Anyone who has taken classes in circuit
analysis is familiar with calculating delta-wye conversions, from delta to wye,
and from wye to delta. My introduction was not for resistor circuits, but for transformers
used in electric power distribution systems. That was way back in the mid 1970s
whilst in a high school electrical vocational program, where rather than take a
full day of traditional classes, half of each day was spent engaging in a mix of
theory hands-on practical experience, doing motor control, security wiring, household
and industrial wiring, service entrance and load center installations, etc. This
"Solving
Delta and Wye Networks by Transformation" article appearing in a 1966 issue
of Radio-Electronics magazine presents a nice introduction to technique...
Exodus Advanced Communications is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. We are pleased to announce
the
Exodus Model AMP2030-LC, ideal for broadband EMI-Lab, Comm. and EW applications.
Class A/AB linear design for all modulations & industry standards. Covers 1.0-6.0 GHz,
producing 300 W Minimum, 200 W P1dB and 55 dB minimum gain. Excellent
flatness, optional monitoring parameters for Forward/Reflected power, VSWR, voltage,
current & temperature sensing for superb reliability...
As of this day (December 27), we are approaching
the December 30 date whereon in the year 1953 the first commercially available color
television set - the Admiral C1617A - went on sale. Mac McGregor and his repair
shop technician, Barney, had been
servicing color TVs since at least February 1955 as printed in
a Radio & Television News story titled, "Barney Takes on Color." This
particular edition laments the increasing cost of servicing color television sets
as they get increasingly complex. Mac and Barney agree that one of the reasons for
service cost is having to work with the newfangled printed circuit boards. Those
early PCBs...
Sibelco mines quartz which at
this time is the world's sole source of crucible material used in growing silicon
boules. "Ultra-high-purity
quartz is an essential component to semiconductor chips, and the only places
in the world that can meet this need are two mines in a small North Carolina town."
It
unfortunately
is located in
Spruce Pine, NC, one of the places devastated by Hurricane Helene. The town
and its roads were washed away by 24 inches of rain. "It's flooded up to the awnings,
about 10 feet. Lower street was destroyed." If the mine were destroyed (which it
was not), "it would likely [be] a few years of major disruption while techniques
to generate alternatives were scaled up. But the disruption would be pretty catastrophic."
Access to the mines and electric power have been disrupted.
Sibelco is headquartered
in Belgium, also home to Agatha Christie's ubersleuth
Hercule Poirot.
The April 1969 issue of Electronics
World magazine featured a collection of ten articles dealing with
filter design and application, authored by experts in the field.
This one discusses which filter types - lumped element (inductors and capacitors),
distributed element (stripline, microstrip, etc.), waveguide, cavity - are best
fitted for use based on the intended application. Power handling, rejection requirements,
inband insertion loss, physical size, cost, stability over time, temperature, vibration,
and moisture as common considerations. Sometimes the decision comes down to designer
preference, manufacturing complexity, desire...
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