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5 of the December 2020 homepage
archives. Monday 14
 It was a big deal in 1944 when Austrian physicist
Dr. Felix Ehrenhaft announced that he had discovered "magnetic
charges," aka magnetic monopoles. He claimed based on numerous kinds of experiments
that a reversible "magnetic current" existed around current-carrying conductors.
It seems based on my reading of this Radio-Craft article that he believed there
existed mono-magnetic particles of some sort analogous to electrons and protons.
Later experiments seems to indicate that high intensity light beams could also produce
evidence of magnetic currents. Dr. Ehrenhaft widely promoted his conclusions
and invited doubters to examine his apparatus. Based on some Web searches on the
topic, independent researchers were not able to reproduce his findings, so his work
eventually faded into the background. Some credit his experiments with light for
demonstrating the particle nature of light's ability to accelerate masses. The most
profound implication of proving the existence of magnetic monopoles...
 "Stanford University engineers have developed
an airborne method for imaging underwater objects by combining light and sound to
break through the seemingly impassable barrier at the interface of air and water.
The researchers envision their hybrid optical-acoustic system one day being used
to conduct drone-based biological marine surveys from the air, carry out large-scale
aerial searches of sunken ships and planes, and map the ocean depths with a similar
speed and level of detail as Earth's landscapes. Their 'Photoacoustic
Airborne Sonar System' is detailed in a recent study published in the journal
IEEE Access..."
 Here is a really good introductory article
on electromagnetic
(EM) fields as they pertain to inductors, transformers, and antennas. It appeared
in the April 1942 edition of QST magazine. The FCC had only been in existence for
eight years at the time and was pretty much just figuring out how to regulate the
heck out of everything. The author discusses compliance issues for these newfangled
RF devices that were becoming more and more numerous. Interestingly, the first sentence
says, "Every time you threw the transmitting switch in pre-war days...," bringing
to mind how the Feds banned Amateur Radio during most of World War II for security
reasons as well as to assure that scarce resources went toward building and servicing
military gear as needed. Many Hams offered their gear either as a donation...
 RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. Chances are you
have never used a spreadsheet quite like this (click
here for screen capture). It is a full-featured RF system cascade parameter
and frequency planner that includes filters and mixers for a mere $45. Built in
MS Excel, using RF Cascade Workbook 2018 is a cinch and the format
is entirely customizable. It is significantly easier and faster than using a multi-thousand
dollar simulator when a high level system analysis is all that is needed. An intro
video takes you through the main features...
 Millions of Britons do not know the internet,
the colour television and jet engine are
British inventions, a survey has claimed. Around half of 2,000 adults polled
were not aware that London based Sir Tim Berners-Lee created the World Wide Web
in 1989. 55% did not realise John Logie Baird, of Dunbartonshire, was the first
person to demonstrate a working colour television in 1928. And 51 per cent did not
know Frank Whittle from Coventry made the very first jet engine having patented
the invention in 1928. 'For the last 50 years the award has celebrated ground-breaking
engineering innovations that have established the UK as a global leader,' said Dr
Dame Sue Ion DBE, chair of the Royal Academy of Engineering..."
 Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated 4-port vector
network analyzer (VNA) calibrator, between- and in-series connector adaptors,
attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner.
Special test fixtures for calibration and multicoax cable assemblies. Frequency
ranges from DC through 110 GHz. Please contact Withwave today to see how they
can help your project succeed.
Sunday 13
 For the sake of avid cruciverbalists amongst
us, each week I create a new crossword puzzle that has a theme related to engineering,
mathematics, chemistry, physics, and other technical words. This December 13th
Electronics Theme crossword puzzle, as always, contains no names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless
it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the
Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!
Friday 11
 Little did Ham radio operators know in April
of 1941 when they were enthusiastically buying equipment for their shacks that a
year later the Federal Communications Commission (FCC) would ban them from broadcasting
from their transmitters. This advertisement for a high-end Hallicrafters receiver
appeared in the April issue of Radio News magazine. Part of the feature
definition includes "calibrated bandspread
inertia controlled," and "micrometer scale tuning inertia controlled." I'm not
sure what the "inertia controlled" part is, unless it refers to how massive metal
disks were sometimes installed inside the chassis on the tuning shaft in order to
give a more solid feel to the control knob, as well as to enable the dial to be
spun and released to rapidly move through a large distance between adjustment points...
 Copper Mountain Technologies (CMT), a leading
developer of innovative RF test and measurement solutions for engineers all over
the world, will present a free webinar entitled "Effective
Use of VNA 'Channels' for Efficient Measurement and Analysis." Tune in on Tuesday,
December 15th, at 11:00 AM EST. The webinar is free, and you can dial in for interactive
participation. CMT Senior RF Design Engineer Brian Walker will be your host as he
describes how "Channels" on a VNA are a very effective way of making a series of
complex measurements simultaneously. Often it is important to visualize a number
of different operational parameters of a circuit while performing tuning or during
production test. In this short webinar Brian demonstrates how one might effectively
use two or more channels to make useful measurements. The full agenda includes allocating
traces vs. allocating channels, setting up multiple channels, calibration...
 "With just a
50-million-electron jumpstart, sensors can power themselves for more than a
year. Researchers from Washington University in St. Louis, led by Prof. Shantanu
Chakrabartty, created self-powered sensors by taking advantage of a quantum effect
known as 'tunneling.' For a device that relies on complex physics, the sensor is
somewhat simple. The components required are four capacitors and two transistors.
From these six parts, Chakrabartty's team built two dynamical systems, each with
two capacitors and a transistor. The capacitors hold a small initial charge, about
50 million electrons each. The 50 million electrons are programmed in during the
device initialization phase..."
 "Hello Americans, This is
Paul Harvey..."
Radio legend Paul Harvey produced and performed a daily show that featured news,
commercials, and commentary. For nearly 75 years, dedicated listeners looked forward
to his show on the local AM radio stations - especially The Rest of the Story.
Scores of wars, natural disasters, crises, deaths, scientific advances, miracles,
and acts of human kindness were commented upon in Mr. Harvey's unique delivery style.
On March 19, 2003, Mr. Harvey did a pitch for the role of Amateur Radio operators
in emergency response roles. The mention was the second item on "page four" of his
Paul Harvey Noon News and Comment program. "America's quiet warriors are
the legion of ham radio operators, 700,000 of them, who are always at ready for
backup duty in emergencies - amateur, unpaid, uncelebrated, civilian radio operators...
 Piconics and Modelithics, are pleased to
announce the availability of 3D models for the CC20T44K240G5-C and CC25T47K240G5-C
conical inductors from Piconics. Both models are included in the latest version,
v20.8, of the Modelithics COMPLETE+3D Library for Ansys® HFSS™. The new models are
validated through multi-substrate S-parameter measurements. Both are validated through
67 GHz, making them well suited for extremely broadband applications. The CC20T44K240G5-C
and CC25T47K240G5-C conical inductors have inductance values of 0.170 and 0.250 μH,
respectively. In addition, the CC20T44K240G5-C is rated for a maximum current of
325 mA, while the CC25T47K240G5-C has a maximum current rating of 230 mA.
Potential use cases for the conical inductors include bias...
 PCBONLINE supplies complex rigid and flex-rigid
printed circuit boards (PCBs)，and
one-stop production with maximum flexibility ranging from prototype sample to mass
production. Rigid-flex, HDI, multilayer, IC-loadboard, LCP 5G optical module, ceramic,
MCPCB. Materials include Rogers, Taconic, Arlon, Isola, Bergquist, Kapton, Panasonic,
and more. After more than 15 years of continuous efforts, PCBONLINE constantly updates
our equipment, improves our technology, and serves you with the highest quality.
Cost and delivery quotations online without the need for multiple phone call and/or
e-mails.
Thursday 10
 Listen to the RF
Cafe Podcast. It is a rare thing when I take exception (i.e., disagree) with
anything Mac McGregor has to say, but on the
subject of soldering I must object. In this 1956 installment of Mac's Service
Shop, Mac and Barney are discussing the plusses and minuses of making a solder joint
mechanically sound prior to applying solder. Barney mentions an article he read
where the author asserts that the only way to make a quality solder joint is to
wrap component leads and wire ends around posts, lugs, eyes, etc. and then flowing
the solder. Both Mac and Barney argue that a perfectly sound solder joint can be
made simply by laying the lead or wire in place and applying solder. From a servicing
perspective that sounds good, because - as I can attest to from much experience...
 "A British company has come up with the novel
idea of using a drone in the sky to provide 5G Internet to consumers and businesses,
utilising an "unique
lightweight, long-endurance airframe certified for civilian use" and powered
by liquid hydrogen, to provide the globe's biggest airborne communications platform.
Stratospheric Platforms chief executive Richard Deakin told iTWire in response to
queries that the High Altitude Platform would be able to stay aloft for nine days.
'Only one HAP is required to provide the service, but some customers may want to
ensure that they have a very high level of service assurance, so much of the modelling
we have done assumes a spare HAP for each one on station, or a spare HAP for say
three HAPS on station etc..."
 "The first man to break
the sound barrier, Chuck Yeager,
and who undoubtedly had 'the right stuff,' died on December 7, 2020 at the ripe
old age of 97. You can't take West Virginia out of the boy. Charles Yeager was born
on February 13, 1923, in Myra, West Virginia, deep in the heart of Appalachian hill
country. As a child, Yeager shot squirrels and rabbits and skinned them for the
family's dinners. In September 1941, armed with his high school diploma, Yeager
enlisted in the Army Air Forces, which was the precursor to today's U.S. Air Force.
Yeager became an airplane mechanic. After tagging along with a maintenance
officer who was flight-testing an airplane, Yeager decided to sign up for a flight
training program..."
 As mentioned many times in the past, some
things never change regarding the basics of electricity and electronics.
Resistance, inductance, and capacitance (termed "capacity" here) are examples
and are addressed in this last of a three-part series which appeared in 1935 issues
of Short Wave Craft magazine. When first starting out in this science, an effective
introduction to the fundamentals can often determine whether a person sticks with
it or finds another area of interest to pursue as a hobby and/or vocation. Analogous
examples of voltage and water pressure, resistance and the diameter of a water hose,
inertia in a spinning mass opposing a change in rate and an inductor opposing a
change in current, etc., are presented along with some good sketches of the principles...
 "Researchers at the Air Force Research Laboratory
(AFRL) in New Mexico have discovered a new way to track and characterize a phenomenon
called 'Sporadic
E' that naturally occurs in the upper atmosphere where large structures of dense
plasma form. These plasma structures, which occur at midlatitude locations around
the world, disrupt radio frequency (RF) electromagnetic waves (or simply 'radio
waves') and impact both DoD and civilian radio systems in positive and negative
ways, depending on the application. 'Previous methods to observe these structures
were insufficient for identifying and tracking these structures over large regions,'
said Ken Obenberger, research physicist at AFRL. 'It would be advantageous to actively
identify where these structures are, where they are going, and how dense they are
and we thought we could find a better way..."
 Linx Technologies, a developer and manufacturer
of antennas and connectors, is pleased to introduce a series of
white bronze N-type RF connectors. Linx N connectors excel in a wide range of
applications including Internet of Things (IoT), cellular IoT (LTE-M/Cat-M1 and
NB-IoT), cellular LTE, LPWA, industrial, automotive, aerospace, and military applications.
The new Linx N connectors are available in a variety of styles, including surface
mount, PCB mount, and cable-crimp mount. Linx is also offering N to N and SMA to
N adapters, providing flexibility in design and integration through a range of solution
options. The N connector series from Linx...
 TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms are
available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
Wednesday 9
 Radio Amateur News began life in
July 1919, then changed its name a year later in July 1920 to Radio News.
In August 1948 the title was again changed to Radio & Television News,
then shortened to Radio & TV News in May 1959. Publication continued
through April 1959. The next month's issue (May 1959) was entitled Electronics
World, with Radio & TV News as a subtitle, and ran through December
1971, when it merged with
Popular Electronics. Popular Electronics began publication as
a new magazine in October 1954 and printed its final issue in October 1982. The
next month it became Computer & Electronics, which continued until
April 1985. From May 1985 through January 1989 it was called Hands-on Electronics.
Believe it or not, in January 1990...
 Aegis Power Systems announces the new VPX1PH3UC310-SA,
a single-phase 85-264 Vac input to 28 Vdc output power supply module with
310 watts and EMI filtering. This rugged slide-in power supply has been developed
in alignment with the Sensor Open Systems Architecture™ (SOSA) technical standard
for use in interoperable systems for sensor management. Using the latest in switching
power technology, this product achieves high efficiency AC-DC conversion with .99
power factor correction in a conduction cooled module with +12 V and +3.3V AUX
outputs in alignment with the SOSATM technical standards. Users with increasing
battlefield demands for C5ISR and embedded computing equipment can make use of advanced
power converter features such as built-in EMI filtering, alignment keys for using
multiple units in one chassis, I2C monitoring and IPMC redundancy, and wide operating
temperature range...
 "Researchers are a step closer to realizing
a new kind of memory that works according to the principles of spintronics which
is analogous to, but different from, electronics. Their unique
GaAs-based ferromagnetic semiconductor can act as memory by quickly switching
its magnetic state in the presence of an induced current at low power. Previously,
such current-induced magnetization switching was unstable and drew a lot of power,
but this new material both suppresses the instability and lowers the power consumption
too. The field of quantum computing often gets covered in the technical press; however,
another emerging field along similar lines tends to get overlooked, and that is
spintronics..."
 Dr. Lee DeForest might have had something
like National Public Radio (est. 1970) in mind when he penned this article in 1933.
In it, the famous vacuum tube amplifier inventor lamented and criticized the commercialization
of broadcasts because of all the paid product announcements (aka commercials) that
had been steadily increasing over the years. He also was critical of the "hit-or-miss,
higgeldy-piggeldy mélange program basis" of programing; i.e., the same station playing
a mix of jazz, opera, swing, syndicated story-telling, etc. The good doctor did
not elaborate on where funding for such dedicated, uncorrupted broadcasts would
originate if not from paying advertisers, and I do not recall ever reading about
a DeForest Radio Network paid for by his vast fortune. I don't like commercials
any more than the next person, but a company deserves time to pitch its products
and/or services if it helps deliver...
 The
InCompliance website has a good synopsis of the
2020 Ig Nobel
Prize winners. "And now for a bright spot in our chaotic world…. The 30th First
Annual (not a typo!) Ig Nobel Prize ceremony was held virtually last month. Not
to be confused with the Nobel Prizes being announced this week in Stockholm, Sweden,
the Ig Nobel Prizes are intended to 'honor achievements that first make people laugh
and then make them think.' This year's Ig Nobel Prize award winners include:
For physics, a team of researchers from Australia, Ukraine, France, Italy, Germany,
the United Kingdom and South Africa for determining experimentally what happens
to the shape of a living earthworm when the earthworm is vibrated at a high frequency..."
 Qorvo / Custom MMIC is a
fabless RF and microwave MMIC
designer entrusted by government and defense industry OEMs. Custom and off-the-shelf
products include switches, phase shifters, attenuators, mixers and multipliers,
and low noise, low phase noise, and distributed amplifiers. From next-generation
long range military radar systems, to advanced aerospace and space-qualified satellite
communications, microwave signal chains are being pushed to new limits - and no
one understands this more than Custom MMIC. Please contact Qorvo / Custom MMIC today
to see how they use their modern engineering, testing and packaging facility to
help your project.
Tuesday 8
 Here are three more
electronics-related comics to help brighten your day. They appeared in a 1947
issue of Radio-Craft magazine. The first one reflects what was a problem
with early compact vacuum tube radios with molded plastic chassis. The gag is the
lady's blaming the problem on something else unrelated. The term "table-top" probably
originated in the early twentieth century to describe products which, prior to miniaturization
efforts using newfangled materials and manufacturing methods, existed only in the
form of large model that stood separately on the floor. The last comic could actually
be applied to today's world...
 "Optical fibres made of silica glass have
been the transmission medium for a high-speed optical communications market estimated
to be worth $40B globally. All-silicon optical transmitter operates at 100 Gbps
The performance of optical fibres is negatively impacted by attenuation - the scattering
of light inside the glass - that causes a loss in transmitted power. According to
the University, this power loss limits the performance of applications requiring
shorter wavelengths. In this new study, published in Nature Communications, researchers
from Southampton University have demonstrated that guiding light through
air-filled fibres offers a potential way to overcome..."
 Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post entitled "Equipment
for an Electrical Engineer's Wish List" that informs people who are looking
to buy test equipment for an electrical engineer. Learn how you could give the gift
of test equipment in a cost-effective manner and add to your favorite electrical
engineer's test bench for 2021. No matter what is on their wish list, Axiom Test
Equipment offers a variety of test equipment to meets their specific needs. Keeping
costs reasonable is possible by either renting equipment for a short-term project
or by purchasing quality used equipment at a fraction of the full price...
Pandemic Psychopathy
I saw this on a financial website:
Patient: "Doctor, doctor! When will this virus end?"
Doctor: "How would I know? I'm not a politician!" --- Sad but
true.
 The October 1952 issue of Boys'
Life magazine story entitled "Tiny
But Tremendous Transistors," contained the first mention of transistors I can
find in the Boy Scouts of America (BSA) flagship publication. Germanium was still
the primary element used for semiconductors at the time, although silicon would
soon replace it - and at a much lower cost. Whereas silicon is found on beaches
all over the world (and everywhere else for that matter) in the form of sand, germanium
at the time was obtained as a by-product of smelting zinc ore (which I didn't know
until reading this story). Today, of course, both elements are abundantly available.
Mr. Cavanaugh points out that although wonderful things are being done with
transistors in the way of improving performance, lowering power requirements, and
reducing product sizes and weights...
 Antenna Physics: An Introduction
2nd Edition, your complete guide to antenna theory, is thoroughly updated and includes
new material to help you better understand the complexities of antenna theory. "World-recognized
antenna technology expert Robert J. Zavrel, Jr., W7SX, is your guide to grasping
a deeper understanding of how antenna systems function. In this book, he clearly
communicates the theory and the mathematics that form the foundations upon which
all antenna designs depend. Although competence with mathematics is necessary to
get the most from this book, Antenna Physics: An Introduction offers knowledge
that will help anyone create their own antenna designs..."
 Nova Microwave is a leader in technically
differentiated electronic and radio frequency Ferrite
Circulators and Isolators
that connect, protect and control critical commercial and military wireless telecommunications
systems. Our staff is dedicated to research and development of standard and custom
design quality Ferrite Circulators and Isolators from 380 MHz to 26.5 GHz.
Available in single or multi-junction topographies, the Nova Microwave product line
of is specifically designed for use in varied environmental and temperature extremes.
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
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