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4 of the December 2022 homepage
archives.  Friday the 30th
 I don't know why, but from May 1963 through
December 1971, John T. Frye's familiar and much loved "Mac's Service Shop"
column in Electronics World magazine abandoned the line drawing header
and "Mac's Service Shop" title, and used instead an image of Mr. Frye's bust
with no mention of Mac or his shop. The stories used all the same familiar characters
- Mac, Barney, Matilda - and scenarios. I took the liberty of adding "Mac's Radio
Service Shop" to the header image for this November 1965 issue. ...but I digress.
The topic of this episode's discussion is the newfangled cable television. Although
a paid subscription service, many people were willing to shell out hard-earned money
in order to receive dependable, clear TV programs. It did nothing for the country
dweller who was putting 20-element directional antennas atop 50-foot towers in order
to get acceptable reception. Not until cable Internet came of age (combined with
megafunding by the government) was the building out of rural networks a profitable
venture. There are still homes less than 50 miles from some cities...
 Anritsu Company has developed the new
Compact Antenna Test Range (CATR) Anechoic Chamber 2 MA8172B configuration for
its New Radio RF Conformance Test System ME7873NR to support 5G millimetre wave
(mmWave) 2 Angle of Arrival (2 AoA) Radio Resource Management (RRM) tests. Anritsu’s
MA8172B solution is unique in industry as it is based on hybrid of IFF (Indirect
Far Field) and DFF (Direct Far Field) test methodologies and this really helps customer
save real estate space. A solution based on all DFF or IFF will be bulky and expensive.
Anritsu helps in providing value to customer by making this new solution lower cost,
smaller footprint, upgradable, and serve multiple test areas. Evaluating UE communications
quality and connection stability during handovers between base stations is a difficult
technical challenge for mmWave mobile communications. Consequently, Anritsu has
developed its MA8172B upgrade model for the Over-the-Air (OTA) CATR...
 There
is now a computer font available to astronomers: Galaxy. Well, not really, not yet,
but at some point there probably will be. The rendition of "Happy New Year 2023
rfcafe.com" was generated automatically by a website called "My Galaxies." Thanks
to thousands of volunteers worldwide that have participated in The Galaxy Zoo's
project of classifying galaxies, a set of letter-shaped galaxies has been identified
that can be used to write words like "rf cafe." It appears that so far God (or the
Big Bang - take your pick) did not create a full set of upper case letter-shaped
galaxies. Some letters can be considered upper or lower case, like Cc Ii Jj Oo Pp
Ss Uu Vv Ww Xx Zz. As you might expect, there are number-shaped galaxies as well.
After all, mathematics is the language of the universe. Judging by the shape of
the numbers ""1" and "7," and the fact that MyGalaxies.co.uk domain is registered
in the UK, I'm guessing the selected galaxy shapes are modeled after the European-style
numeral set...
 Radio Shack, like so many of America's original
great companies, was born in the early formative year of electronics and lived long
and prospered through the rest of the century during its glory days, then eventually
waned into insignificance and obsolescence after around Y2K. It is not always simply
an unwillingness to adapt to new technologies and methods that doomed Radio Shack
and those like them. The forces behind those life cycles are often beyond their
control because start-ups vying for market share do not carry the burden of and
have to deal with established investments in people, facilities, and infrastructure.
This advertisement from a 1947 issue of QST magazine was from the original
Radio Shack in Boston, Massachusetts. The company was bought by Tandy Corporation
in the 1960s, then sold to hedge fund operator General Wireless in the mid 2000s.
Radio Shack filed for bankruptcy in 2015 and the few remaining outlets...
RF Cascade Workbook 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...
 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.
Thursday the 29th
 The Cold War is generally agreed to have
begun between the U.S. and the U.S.S.R. on March 12, 1947, less than two years after
the end of World War II, precipitated by the Truman Doctrine on March 12th,
thereby enraging Stalin. It was thus considered "cold" because while no armed conflict
("hot" action) occurred directly between the two countries, third party countries
fought with each other at the behest of USSR and the U.S. using weapons and finances
provided by the aforementioned countries. The Cold War officially ended on December
26, 1991, following the dissolution of the Soviet Union. In the interim, threats
of nuclear war haunted the Earth's inhabitants. Once missiles were developed capable
of delivering nuclear warheads between Russia and America - in both directions -
it became necessary to build a network of over-the-horizon radars that could detect
the flights of such projectiles and provide advanced notice of incoming atomic disaster.
Fortunately (or unfortunately), a philosophy of Mutually Assured Destruction (MAD)
ultimately prevented such an unfathomable scenario from ever taking place. The Ballistic
Missile Early Warning System, reported here in a 1960 issue of Electronics World
magazine...
 "Will an electron escaping a molecule through
a quantum tunnel behave differently depending on the left- or right-handedness of
the molecule? Chemists have borrowed the phrases "left-handed" and "right-handed"
from anatomy to describe molecules that are characterized by a particular type of
asymmetry. To explore the
concept of chirality, look at your hands, palms up. Clearly, the two are mirror
images of one another. But try as we might to superimpose them, they will not overlap
completely. Such objects, termed "chiral," can be found at all scales in nature,
from galaxies down to molecules. Each day, we experience chirality not only when
we grab an object or put on our shoes but also when we eat or breathe: our taste
and smell can distinguish two mirror images of a chiral molecule..."
 RF Cafe visitor Jim F. writes occasionally
to fill me in on some details of his experiences with some of the vintage radios
that I post schematics and parts list for. In this case it is the
Sparton Model 7−46, on which he fondly remembers as a boy listening to the Cassius
Marcellus Clay, Jr. (aka Mohammad Ali) fight during the 1960 Summer Olympics in
Rome, Italy. "The party line telephone sat on top of it," recalls Jim. He sent a
photo of a 7−46 cabinet and a radio Star Roamer multi-band receiver which was a
Knight-Kit. This schematic and parts list set from the February 1947 issue of Radio
News magazine includes not just the Sparton 7−46, but also the 7−46PA, 8−46, and
8−46PA radios. There are still many people who restore and service these vintage
radios, and often it can be difficult or impossible to find schematics and/or tuning
information...
 While we're on the topic of VTVMs, Popular
Electronics magazine ran a 5-part series on test equipment usage. This installment
(part 4) is on the use of a
vacuum tube voltmeter (VTVM) for making DC measurements. Don't pass over the
article just because it refers to a vacuum tube tester since there are lessons that
apply to even the most modern transistorized, computerized meter. Author Larry Klein
discusses mainly the DC functions, providing both functional descriptions of the
circuits and how to use them for making accurate measurements. FET-input digital
multimeters (DMMs) have largely replaced VTVMs, but they can still be found in some
older electronics development labs and hobby benches...
 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 (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1
scale so that measurements can be made directly using Visio built-in dimensioning
objects. Page templates are provided with a preset scale (changeable) for a good
presentation that can incorporate all provided symbols...
 Innovative Power Products has been designing
and manufacturing RF and Microwave passive components since 2005. We use the latest
design tools available to build our baluns, 90-degree couplers, directional couplers,
combiners/dividers, single-ended transformers, resistors, terminations, and custom
products. Applications in military, medical, industrial, and commercial markets
are serviced around the world. Products listed on the website link to detailed mechanical
drawings, electrical specifications, and performance data. If you cannot find a
product that meets your requirements on our website, contact us to speak with one
of our experienced design engineers about your project.
Wednesday the 28th
 For many years, Electronics World
magazine ran a "Recent
Developments in Electronics" feature that highlighted guess what? Yep, recent
development in electronics. This July 1965 issue reported on, amongst other things,
the largest (at the time - 60 feet) three-axis radio frequency antenna, manufactured
by Philco, for use in satellite tracking. Not even a full two years had passed since
the launch of America's first transponder-equipped satellite, SCORE. Also shown
was a "Frigistor" for electronic cooling, exploiting the thermoelectric effect.
The only patent I could find is registered in Great Britain (GB1033018A). The trademark
(expired) says, "Thermoelectric Cooling Assemblies Consisting of One or More Couples
of P and N Type." Another key item was a huge (for the time - a whopping 60 feet)
RF anechoic chamber...
 ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies for
amplitude and phased matched VNA applications as well as standard & precision
RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the
iBwave component library. They also provide custom coax solutions for applications
where some standard just won't do. A partnership with Newark assures fast, reliable
access. Please visit ConductRF today to see how they can help your project!
 These three
electronics-themed comics appeared in circa 1952 and 1953 Radio &
Television News magazine. For some reason the early 50s were a little comic
challenged, that is to say only one or two usually appeared in each edition. I really
like the one with the guy hanging from the antenna! He needs the rotator to turn
him back over the roof. You probably have to have lived in the vacuum tube TV era
to appreciate the humor in the comic with the homeowners rolling out the red carpet
for the repairman. It's hard to make out the artists' names, but they have appeared
on other comics of the era. If you enjoy comics like this, there is a growing list
of other comics at the bottom of the page you can check out...
 "The value of the
fine structure constant - perhaps the most important constant in nature as it
dictates the strength of electromagnetism - has been measured directly by researchers
in Austria and the U.S. The technique they used involves measuring how much the
polarization of light rotates as it passes through a magnetic topological insulator,
and while it is not as accurate as other methods, the researchers believe its directness
could lead to cleaner tests of whether this supposed constant varies over time.
The fine structure constant, denoted α, is a dimensionless number with a physical
interpretation that has evolved alongside physicists' understanding of electromagnetism.
When Arnold Sommerfeld introduced it in 1916, it was the velocity of an electron
in the first circular orbit of the Bohr model of the atom, divided by the speed
of light in vacuum. In quantum electrodynamics, it is the coupling constant that
determines the strength of interactions between electrons and photons. Its value
is around 1/137, and if it were even slightly different – perhaps just 1/138..."
 As evidenced in these mid-last-century magazine
advertisements,
Sylvania Electric marketing moguls learned early what sells products by exploiting
the nature of their audience. The cartoon-style ads shown here appeared in social
publications like Look, Life, and Collier's, where both men and women - many of
them numbnuts - were the expected audience. Compare these with the type of cartoon
ads run by Sylvania in "serious" magazines like Radio-Craft. Of course when you
consider some of the other comics printed in the same "serious" magazines, you could
excuse Sylvania if they ran those social magazine ads here...
/jobs.htm" target="_top">
 RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable /jobs.htm"
target="_top">job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
quality visitors...
 Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
procedures.
Tuesday the 27th
 Fred Shunaman, author of the two-part "Nomograph
Construction" article in Radio-Craft magazine (c1946), notes that the
nomogram is "equal to an infinite number of charts." Part I covered the basics
of nomograph construction with voltage, current, and resistance. Part II discusses
strategies for best placement and scale types to use for optimizing the accuracy
and usefulness of a nomograph. An inset key is added to guide the used on how to
interpret the results. Figures 1 through 4 and Nomographs A and B are in Part I...
 The USPTO, issued its first patent on July
31, 1790, assigned to Mr. Samuel Hopkins for a process of making potash. That
was three years after creation of the office in 1787. President George Washington
signed that one. You might think the country's first issued patent is numbered one
(later designated X000001), but that's not the case. Enumeration did not begin until
July 13, 1836 when U.S. patent "No
1" was issued to Mr. John Ruggles for a traction wheel for steam locomotives.
The U.S. government had issued 9,957 patents before starting a numbering system
so for any patent number, add 9,957 for its actual place in line. The one millionth
patent was assigned in 1811. #2,000,000 happened in 1935. The ten millionth patent
was issued in 2018 for coherent ladar using quadrature detection. #11,000,000 was
awarded just three years later. By process of elimination, I found that as of this
very moment (10:30 am EST, December 27, 2022), the highest patent number assigned
per the USPTO's website is #11,540,433...
 I just couldn't pass up this headline and
graphic. Those spinning electrons look like something the
The Jetsons. "Researchers at Nanjing University
in China have used a
superconducting quantum chip to simulate a system of particles that are neither
fermions nor bosons. As part of this simulation, they measured a parameter known
as the quantum geometric tensor that provides local information about the system's
topological properties. The work marks the first time this quantity has been measured
in a so-called non-Abelian system - a result that will be useful for studying the
physics of complex systems such as topological materials. According to quantum mechanics
and quantum field theory, all elementary particles fall into one of two groups:
fermions or bosons. Fermions such as electrons obey the Pauli exclusion principle,
meaning that no two fermions can ever occupy the same quantum state. This propensity..."
 In 1959, Popular Electronics magazine
ran a 5-part series on test equipment usage. This final article is on the use of
a
vacuum tube voltmeter (VTVM) for making accurate AC and resistance measurements.
Also in this edition is a construction article for RCA's VoltOhmyst VTVM kit, so
the two compliment each other. Author Larry Klein discusses mainly the AC and ohmmeter
functions, providing both functional descriptions of the circuits and how to use
them for making accurate measurements. A very high input impedance is important
to minimize the loading effect of the instrument by keeping it from becoming a part
of the circuit under test. FET-input digital multimeters (DMMs) have nearly totally
replaced VTVMs, but they can still be found in some older electronics development
labs and hobby benches...
RF Cascade Workbook 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...
 Amplifier Solutions Corporation (ASC) is
a manufacturer of amplifiers for commercial & military markets. ASC designs
and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers
for low, medium and high power applications using Gallium Nitride (GaN), Gallium
Arsenide (GaAs) and Silicon (Si) transistor technologies. ASC's thick film designs
operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film
designs that operate up to 20 GHz. ASC is located in an 8,000 sq.ft. facility
in the town of Telford, PA. We offer excellent customer support and take pride in
the ability to quickly react to evolving system design requirements.
Monday the 26th
 Many thanks to website visitor Mr. Ferrous S.
for providing an OCR version of this
Carl & Jerry story, and for writing the following: "The earliest optoelectronic
devices are photodetectors, and the basis of photodetectors is the discovery and
research of photoelectric effects. In 1873, Willoughby Smith discovered the photoconductivity
of selenium. In 1888, German Heinrich Hertz observed that when ultraviolet light
irradiated the metal, it could make the metal emit charged particles. In 1890, Philipp
Lenard determined the charge−mass ratio of charged particles and proved them to
be electrons, thus clarifying the essence of photoelectric effect. In 1900, German
physicist Planck introduced energy quantum into the study of blackbody radiation,
and proposed the famous Max Planck formula to describe the phenomenon of blackbody
radiation, which laid the foundation for quantum theory. In 1929, Kohler made a
silver-oxygen-cesium photocathode and a photocell resulted. In 1939, Vladimir Zvorakin
of the Soviet Union made a practical photomultiplier tube...
 Well... anyway it was 50 years ago referenced
to the year this story was published in the 1937 issue of Radio-Craft magazine.
That makes it 85 years ago referenced to 2022. The story's point is that half a
century had passed already since the confirmation of existence of electromagnetic
(EM) waves as proposed by James Clerk Maxwell.
Heinrich Hertz's "Funken-Induktor" (spark inductor) and his "Knochenhauershen
Scheiben" (Karl-Wilhelm Knochenhauer's disk-type capacitors) were key to Hertz's
ability to generate, transmit, and receive EM energy. The work originated from attempts
to prove that light was a form of electromagnetic waves...
 "Data obtained from
SCaN Testbed experiments is paving the way for the future of space radio, with
cognitive communication systems combining software-defined radios with AI/ML to
improve performance and resilience of RF units. Developing electronics for space
applications is certainly an exciting task, but it can become a real problem if
the designer fails to address the critical robustness requirements of the application.
It’s crucial to consider not only the harsh environment of space, but also the fact
that physical maintenance is very scarce and expensive. Therefore, it’s not a surprise
that RF devices for space communication are evolving from fixed and single-purpose
hardware-based systems to flexible, robust, and reprogrammable software-defined
radios (SDRs). To ensure proper operation in space, SDRs must be prepared to endure
harsh conditions. Thus, they must employ radiation-hardened electronics..."
 Edward Weston was a pioneer in the
photoelectric cell field. His "photronic" cell was one of the first successful
devices for commercial use. Just like with early battery cells, photoelectric cells
of the era required a liquid medium to facilitate electron transfer and thereby
generate electric current. The lead nitrate compound used by Weston is now considered
a possible human carcinogen. Mr. Brooke Clark has a web page with extensive data
on the history of Weston's photoelectric sensors, meters, test data, patents, and
history of his company - which now has the name Huygen Corporation. Photoelectric
science has advanced significantly in the 80 years since this article was published.
A good website to visit regularly if you like following progress on photocell technology
is Semiconductor Today...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
 Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly
for design engineers needing low volume or prototype multi-layer printed circuit
boards. Free Passive Components: Bittele
Electronics is taking one further step in its commitment of offering the best service
to clients of its PCB assembly business. Bittele is now offering common passive
components to its clients FREE of Charge.
Sunday the 25th
 This Radio Theme
Christmas Crossword Puzzle for December 25th has many words and clues related
to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry, physics,
and other technical subjects, along with a holiday message. There is also a holiday
greeting contained within. As always, this crossword 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., Reginald Denny or
the Tunguska event in Siberia). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy!
 Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners (hence "Triad") with
over 40 years of accumulated knowledge of what is required to design, manufacture,
market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA,
bi-directional, and frequency translating amplifiers are available, in formats including
tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology
partner than a vendor for our line-of-sight communications product line." Please
check to see how they can help your project.
 By request,
the Polymer Shapes company of Santa
Fe Springs, CA, has been added to the Plastics
Manufacturers &
Services vendor pages. For more than 70 years, Polymer Shapes has supplied plastic
sheets, rods, tubes, film, and similar products from material such as ABS, acetyl,
acrylic, expanded foam, PVC, nylon, PAI, phenolic, PET, PETG, polyurethane. A wide
range of services are available from their knowledgeable and highly skilled staff
includes thermoforming, fabrication, CNC machining, laser cutting, and CAD design
and programming.
Friday the 23rd
 Ever
vigilant for ICBM's rocketing across the North Pole from Russia, NORAD maintains
a constant watch on the area, and needs to be careful not to get a false alarm when
Santa Claus takes off
The Night Before Christmas (aka Christmas Eve) with his sleigh full of toys
for good boys and girls. Assuming his sled has not been upgraded to some non-metallic
material, and that the bells on on Dasher, on Dancer, on Prancer, on Vixen, on Comet,
on Cupid, on Donner and on Blitzen (and Rudolph, of course) are still made of brass,
the radar cross section (RCS) is pretty significant and could easily be mistaken
for a missile in flight. After all, that sleigh must be moving at supersonic speeds
to cover the entire Earth in one day. Some people argue against a Santa Clause by
citing he could not possibly deliver presents to everyone in just a few hours, but
by trekking westward at an average of about 1,000 mph (relative to the equator)
he can exploit the surface rotation and remain in a given time zone. From everyone
at RF Cafe (that's Melanie and me), we say, "Happy Christmas to all, and to
all a good night!"
 "Nagoya University and Toyota Central
R&D Labs in Japan claim a
record low on-resistance (RON) for vertical gallium nitride (GaN) Schottky barrier
diodes (SBDs) of between 0.57mΩ-cm2 and 0.67mΩ-cm2. The breakdown voltages (BVs)
of between 660V and 675V, dependent on dimensions, were 84.4% of the value expected
for ideal parallel plane structures. One target for such devices is low-loss power
switching applications. Although vertical GaN pn diodes have similar performance
in terms of RON and BV, the higher turn-on voltage (VON~3V for pn, compared with
0.74 for Nagoya/Toyota's SBDs) results in wasted power. The team comments: 'Compared
to silicon carbide (SiC) JBS rectifiers, the GaN JBS diodes represent an early stage
of development. Thus, the ability to realize high-performance vertical GaN JBS diodes
can bring GaN power electronics to the next level.' The researchers used a junction
barrier Schottky (JBS) diode structure (Figure 1). The 10μm drift layer of silicon
(Si)-doped n-GaN was grown on freestanding..."
 The January 2023 issue of QST magazine
highlights
Dr. Joseph Hooton Taylor, Jr., K1JT. An accomplished radio astronomer,
Dr. Taylor's feature is the first of what will be a year-long theme to "highlight
amateurs who have achieved recognition in areas outside of, or related to, amateur
radio." I think that is a great idea and look forward to seeing who they come up
with. Too bad that the ARRL doesn't post stories like this so that non-members can
have access to them; they would serve as a great motivation to people considering
earning a new license or upgrading to a higher class. "JT. Since 2001, those two
letters have signaled digital transformation in ham radio. They are the initials
of the pioneering scientist and amateur radio innovator, Joe Taylor, whose software
suite, WSJT - updated to WSJT−X - revolutionized ham radio. Today, the warble of
JT8 dominates, but the tones of FT4, JT9, SWPR, and Q65 all emerge from the static
to connect hams the world over with signal-to-noise ratios as low as −44 dB..."
 Quantic PMI, a leading supplier of custom,
high-reliability MIC/MMIC components and subsystems for applications in space,
military, communications, commercial and consumer electronics systems for more than
three decades, introduced six new products this month of December in their extensive
line of RF and microwave components. Included amongst them are an ultra-high speed,
high sensitivity threshold detector for 4-4.5 GHz, a broadband variable attenuator
/ modulator for 0.5-18 GHz, and a directional coupler for 33-36 GHz. Contact
Quantic PMI today for more information...
 Gray market electronic components are not
just a recent problem. Long before IC foundries were set up in China, Indonesia,
Vietnam, etc., to produce counterfeit semiconductor components, there were unscrupulous
manufacturers turning out bogus components of all sorts. Marking unauthorized microprocessor
and amplifier packages with an industry-leading brand name and part number is a
real problem, but such practices extend back to the vacuum tube era. This story
from a 1957 edition of Popular Electronics magazine tells the story of
how companies like General Electric and Sylvania dealt with the situation...
/jobs.htm" target="_top">
RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable /jobs.htm"
target="_top">job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
quality visitors...
 Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
Thursday the 22nd
 Nomograms (aka nomographs) have always been
a great method of providing a quick visual means of relating various quantities
to each other. Careful adjustment of the numerical scales allows a straight line
to be drawn between any two values to determine the value of the third (or more).
An extreme example is the Link Coupling Nomogram which uses two straight line scales
and a curve graph. As can be seen in this
Transformer Turns Ratio nomogram from a 1965 issue of Electronics World
magazine, a square root function (TR=√Z1/Z2) can be easily accommodated with a straight
line from the input impedance scale to the output impedance scale, and extending
it to the third turns ratio (TR) scale. A similar nomogram can be constructed for
turns ratio needed for specific input and output voltage, current, or power. A list
of many other nomographs/nomograms is given at the bottom of the page...
 "When a material with magnetic properties,
constructed from appropriately selected layers, is illuminated by a pulse from an
X-ray
laser, it instantly demagnetizes. This phenomenon, so far poorly understood,
could in the future be used in nanoelectronics, to build, for example, ultrafast
magnetic switches. An important step toward this goal is a new simulation tool developed
by a Polish-German-Italian team of scientists as part of a joint research project
between the European XFEL and IFJ PAN. No information-processing device can operate
at a speed faster than that at which the physical phenomena underlying its operation
occur. That is why physicists continue to seek phenomena that run on increasingly
shorter spatial and temporal scales, yet can be controlled relatively easily. One
promising research direction seems to be the demagnetization process of ferromagnetic
multilayer materials..."
 Halli(gan) and (hand)crafters,
a portmanteau of those two indicated words, was founded in Chicago in 1932 by William
J. Halligan. The company designed and manufactured radio equipment for hobby, commercial,
and military applications and quickly became very popular amongst their users. As
was customary for U.S. businesses, Hallicrafters ran a Christmas advertisement in
the January issue of magazines where they appeared, as with this 1941 issue of QST.
The January edition, as is common even now, is typically mailed in early December,
getting it in the hands of readers in time for Christmas...
 Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his December 2022 newsletter that
features his short op−ed entitled "The
Resurgence of Microwave Directed Energy Weapons." The premise of directed energy
(DE) weapons is to blast RF/microwave energy at a specific frequency or band of
frequencies at a high enough power to confuse or totally disable drones and/or missiles
while in flight, before reaching their intended targets. Sam argues reasonably that
the relatively low power and aiming requirements of a microwave directed energy
system can be much more effective than a high power laser beam that must be aimed
and track the target precisely enough to make surface contact. An RF system can
make multiple "shots" in the same time required for a laser power supply to recharge
between shots. A great example of how DE works can be seen in this decade-old video
of an Active Denial System use to disperse unruly crowds. The targets are humans,
but the reactions are analogous to how radio receivers are affected...
 An RF Cafe visitor sent this equation to
me a few years ago. It can be found all over the Internet (including here), but
I cannot determine a definite origin. Mathematicians claim that math can explain
everything in the universe, which is not quite true. It can't for example, explain
why my next-door neighbor is a junk hoarder. This
Christmas equation
does not appear to begin with a particular application; it looks like something
from a set of textbook end-of-chapter problems. Even if you don't celebrate Christmas,
it provides a secondary benefit by demonstrating rules for the manipulation of logarithms
and exponents along with basic algebraic rearrangements of terms.
 New Scheme rotates
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place to be.
 Anritsu has been a global provider of innovative
communications test and measurement solutions for more than 120 years. Anritsu manufactures
a full line of innovative components and accessories for
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Equipment including attenuators & terminations; coaxial cables, connectors &
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