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archives. Sunday the 14th
 It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics as those for Visio™. Each of the 1,000
or so symbols was exported individually from Visio™ in the EMF file format, then
imported into Word on a Drawing Canvas. The EMF format allows an image to be scaled
up or down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
 This
Physics & Science Theme crossword puzzle for Valentine's Day
2021 contains only words and clues related to engineering, mathematics, chemistry,
physics, and other technical words. 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.,
Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy!
Friday the 12th
 Mackay Radio & Telegraph Company, established
in 1925 in Nevada by Clarence Mackay as a sort of spin-off of his father's Commercial
Cable Company, is not usually a name that comes to mind when recalling early communications
pioneers. Mackay was one of the earliest radio and telegraph companies, but also
is still in business today under the name of Mackay Communications, Inc., based
in Raleigh, NC. That makes Mackay one of the oldest electronics companies in the
United States and in the world. Congratulations to them for surviving the cut-throat
realm of corporate mergers, buy-outs, and hostile takeovers. As with nearly all
technology concerns during World War II, Mackay did its part to help the Allies
beat back the advances of Communism, Marxism, and Socialism by designing and manufacturing
state-of-the-art radio communications systems...
 "A low-power and non-volatile technology
called the
memristor shows initial promise as a basis for machine learning.
According to new research, memristors efficiently tackle AI medical diagnosis problems,
an encouraging development that suggests additional applications in other fields,
especially low-power or network 'edge' applications. This may be, the researchers
say, because memristors artificially mimic some of the neuron's essential properties.
Memristors, or memory resistors, are a kind of building block for electronic circuits
that scientists predicted roughly 50 years ago but only created for the first time
a little more than a decade ago. These components, also known as resistive random
access memory (RRAM) devices, are essentially electric switches..."
 This "UFO Patents" story has gotten a lot of traction in the last week
or so (play
Twilight Zone theme in background while reading). It is based on patents filed
by U.S. Navy scientist,
Dr. Salvatore Pais, who works at the
Naval Air Warfare Center,
(NAWC - source of the very popular
Electronic Warfare and Radar Systems Handbook). A
Google Patents search on Dr. Pais' name returns some rather
odd designs that include "Craft using an inertial mass reduction device" (US10144532B2),
"High frequency gravitational wave generator" (US10322827B2),
and "Plasma Compression Fusion Device" (US20190295733A1).
Maybe he is just a brilliant visionary... or maybe he finally decrypted information
stored in those Area 51
vaults?
 In spite of the proliferation of cellphones
and near ubiquitous communications, there are still many applications that require
private
2-way communications systems. Emergency services like police,
fire, and ambulance; amateur radio, vehicular dispatch for utilities, delivery and
repair services; and anywhere that cellular service is not either available or extremely
reliable, cannot rely on cellphones for mission critical needs. There are a lot
of legacy 2-way radio system antennas and associated towers still being used and
many new installations in place. Word has it that use of Citizen Band (CB) radio
is on the rise amongst not just truck drivers but everyday drivers and base station
operators - largely for the anonymity factor...
 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...
 Nancy Friedrich, a name I haven't seen in
a while (she used to be the editor of Microwaves & RF magazine), has
an interesting article on the Aerospace & Defense Technology website entitled,
"Electronic Warfare: Vying for Control of the Electromagnetic Spectrum." The flood
of wireless everything has made protecting and securing the EM environment an increasingly
difficult task. She begins, "Over the past decade, preeminent countries involved
in major military conflicts mainly focused on asymmetrical warfare — surprise attacks
by small groups armed with modern, high-tech weaponry. During that same period,
however, near-peer adversaries began attaining impressive electronic warfare (EW)
capabilities. As a result, a plethora of new, dynamic threats flooded the EW spectrum,
pushing threat detection and analysis to keep pace. Large military forces now face
ongoing development and evolution to stay ahead of their adversaries..."
 SF Circuits' specialty is in the complex,
advanced technology of PCB fabrication and assembly, producing high quality multi-layered
PCBs from elaborate layouts. With them, you receive unparalleled technical expertise
at competitive prices as well as the most progressive solutions available. Their
customers request PCB production that is outside the capabilities of normal circuit
board providers. Please take a moment to visit San Francisco Circuits today. "Printed
Circuit Fabrication & Assembly with No Limit on Technology or Quantity."
Thursday the 11th
 I know a guy who began in radio back in the
1960s as a
short wave listener (SWL), and then earned his Amateur Radio license
in order to be able to send messages as well as listen to them. Short wave listening
was a very popular pastime for many people - not just technical types - back before
advances in communications made the world, to cite a cliché, "a much smaller place."
Being just a "listener" was much less expensive and less involved that setting up
a transmitting station (often requiring huge cabinets of vacuum tube equipment).
Prior to around the 1960s, the only personal exposure most people had to the rest
of the world was while serving in the military service. Movies, television documentaries,
and magazines like National Geographic provided insight into foreign cultures. As
with radio itself, existence outside your local town was a mystery so fantastical
stories told by cosmopolitan travelers garnered troves of interested listeners.
"All-Wave" radios tuned the AM (and later FM) bands and also included one or more
shortwave bands. Under ideal radio wave propagation conditions, even a simple set
could pick up broadcasts half a world away. Immigrants could listen to happenings
in their home...
 "Conventional adhesives require light or
heat to bond. Scientists from Nanyang Technological University, Singapore (NTU Singapore),
have developed a new way to cure adhesives: passing them through a magnetic field.
The non-contact method of curing leads to adhesives that can be activated on demand.
The 'magnetocuring' adhesive is made by combining a typical commercially
available epoxy adhesive with specially tailored magnetic nanoparticles created
by the NTU scientists. Unlike the two-component adhesives that require the mixing
of two liquids before use, the NTU-developed coating does not need to be mixed with
any hardener or accelerator. The ease of use, according to..."
 Artech House today announced the publication
Radio Wave Propagation Fundamentals, 2nd Edition, by Artem Saakian.
This completely updated second edition of an Artech House classic provides a thorough
introduction to the basic principles of electromagnetic wave propagation of radio
frequencies in real-world conditions, fully updated by including new achievements
in theory and technology. It serves as an invaluable daily reference for practitioners
in the field and as a complete, organized text on the subject. This comprehensive
resource covers a wide range of essential topics, from the classification of radio
waves, electromagnetic wave theory, and antennas for RF radio links, to the impact
of the earth surface on the propagation of ground waves, atmospheric affects in
radio wave propagation, and radio wave reception...
 In the present era, designing a
frequency converter circuit consists in most cases of picking
from a catalog an IC or connectorized component that has the characteristics you
need from a gain and mixer spurious product standpoint. Add a couple filters, a
local oscillator (although in some cases the oscillator is part of the IC), and
a power supply, and you're good to go. Of course there are special cases where you
have to use a basic mixer and do everything yourself, but even that is simpler than
designing a primary circuit using diodes or vacuum tubes as rectifiers. Obtaining
match sets for good mixer spurious product cancellation is very difficult, especially
in a large volume production environment. It really is amazing what engineers and
hobbyists of yore were able to accomplish using point-to-point wiring and a slide
rule. Here is a good article form the February 1941 QST magazine...
 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.
Two new cavity bandpass filters have been introduced. The AB5424B1314
has a center frequency of 542 MHz and a bandwidth of 52 MHz. Insertion
loss in the passband is less than 1 dB. The AB800B843 is an LTE band narrow
band filter centered at 800 MHz with a bandwidth of 12.3 MHz and a 2 dB
passband insertion loss. Custom RF power directional coupler designs...
 RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
Wednesday the 10th
 Due to the era in which this "Electronic Puzzle Square" appeared (1945), I made a couple edits
to help prevent misinterpretation. For instance the "mfd." in question 5 is microfarad
(μF) in today's units standard. Question 4 originally had an upper case "E," which
was a typo since it should have been a lower case "e," as in the base of the natural
logarithm. When working Q7, leave the input and output terminals open when calculating
the equivalent resistance; it's not like doing a "Pi" to "Tee" attenuator conversion.
Q11 originally had "logE" where it should have been just "e." Q9 is a piece of cake.
Question 15 assumes you know the resistance per foot of #25 B&S (AWG) copper
wire, which you can find here (hint: it's 32.4 Ω/1000 ft)...
 "To remain competitive in the field of the
Internet of Things, even medium-sized industrial and process metrology companies
need to increasingly integrate their sensor circuits into ASICs. The semiconductor
industry is currently meeting this need with lower costs for development cycles
and decreasing quantity hurdles. However, this is not occurring often enough in
chip packaging, meaning that ASICs requiring individual packages are at risk of
being bogged down due to the quantity hurdles of package service providers, most
of which are Asian. This issue is now resolved by a consortium of seven partners
from industry and research. Radar sensors for industrial and process metrology,
as addressed in the project 'Glass Interposer Technology for Implementing Highly Compact Electronic
Systems for High-frequency Applications (GlaRA) sponsored by BMBF..."
 Measuring
voltage standing wave ratio (VSWR) is a fairly common and simple
operation these days with readily available and relatively inexpensive test equipment.
Inserting a power meter in series with a signal to measuring the incident and reflected
power, or even simpler, inserting a bidirectional power coupler in series with the
signal and measuring the difference between the forward and reverse ports is a routine
matter for even modestly equipped laboratories, Ham shacks, or field operations.
Simply plug the two values into the following equation for the answer: VSWR=(1
+ β)/(1-β), where β=√(Prev/Pfwd). What if all you have is
an oscilloscope, then how would you make the measurement? Actually, the calculation
is even simpler because you use the ratio of the peak incident and reflected waves,
but making the measurement requires more work. This article presents one way to
get the job done...
 Providing full solution service is our motto,
not just selling goods. RF & Connector Technology has persistently pursued a management
policy stressing quality assurance system and technological advancement. From your
very first contact, you will be supported by competent RF specialists; all of them
have several years of field experience in this industry allowing them to suggest
a fundamental solution and troubleshooting approach. Coaxial RF connectors, cable
assemblies, antennas, terminations, attenuators, couplers, dividers, and more. Practically,
we put priority on process inspection at each step of workflow as well as during
final inspection in order to actualize "Zero Defects."
 Digital Intelligence Systems (DISYS), a global
staffing, IT consulting & managed services firm with more than 33 offices worldwide,
is in search of an RF Design Engineer. This engineering position will report to
the manager of RF Solutions, primarily support the Tactical Solutions business unit,
and will have Radio Frequency (RF) engineering as its area of specialization with
design and test of RF electronics circuits and systems as the focus. You will be
responsible for the hands-on design and realization of RF passive and active circuits
used in phased array antennas, larger RF systems, and other RF components. Also,
you will design and test circuits for receivers, transmitters, local oscillators,
and RF subsystems. Designs typically range in frequency from VHF through 20 GHz.
Simulate circuit and system performance using analytical software such as AWR Microwave
Office, VSS, Agilent ADS, System Vue, and MATLAB...
 Reactel has become one of the industry leaders
in the design and manufacture of RF and microwave filters, diplexers, and sub-assemblies.
They offer the generally known tubular, LC, cavity, and waveguide designs, as well
as state of the art high performance suspended substrate models. Through a continuous
process of research and development, they have established a full line of filters
of filters of all types - lowpass, highpass, bandpass, bandstop, diplexer, and more.
Established in 1979. Please contact Reactel today to see how they might help your
project.
Tuesday the 9th
 These four
electronics-themed comics appeared in the March 1944 issue of
Radio-Craft magazine. People worldwide were still obsessed with radio and
many forms of media created content to feed the frenzy. For that matter, any form
of electronic gizmo was deemed to be magical to the average person. All sorts of
fantastical inventions were envisioned. In 1944, less than half the households had
even one television set, and hard as it may seem to believe, many did not have a
single radio, either. Newspapers and magazines constituted the primary form of news
distribution and consumption. I have to say that the comic with the quasi-Baroque-angel-style
baby holding a "radio-bottle" kind of creeps me out...
 Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog post entitled "Setting up a Home Test System," that discusses the most important
equipment you will need when creating your home's test studio either for hobby endeavors
or for the need to outfit a work-from-home environment due COVID-19 conditions.
Cost of equipment is a significant factor when building your home test studio. However,
keeping costs reasonable is possible by either renting equipment or purchasing quality
used equipment at a fraction of the price which can be found through Axiom's extensive
inventory. Setting up a Home Test System Social distancing has become a new way
of life due to the COVID-19 pandemic and efforts to prevent the spread of the coronavirus.
Instead of daily trips to a test lab or electronic manufacturing facility, many
engineers are being asked to work remotely to minimize contact with others and the
potential spread of the virus. For many, home is the new office and workplace and
for electronic circuit designers, testing is a helpful if not essential part of
working on electronic designs at home...
 "Active Mold Packaging (AMP) is a novel interconnect technology
for IC packaging. Here, the previously unused areas of the epoxy mold compound (EMC)
of an IC package are converted into an active carrier of electrical functionality.
AMP offers additional metallization layers on the surface and in the volume of the
EMC, thus enabling a new approach towards mm-wave applications. The LPKF solution
provides simple, time-saving, and space-saving antennas with package integration.
The simple, time-saving and reliable technology is based on three proven and standardized
electronic production technologies..."
 Most people know that World War II marked
the point at which a large percentage of American women made a major move from the
role of homemaker to the roles of factory and trades workers. The societal shift
was made necessary because a large percentage of American men were off fighting
the war in Europe and the South Pacific, and therefore were not available to do
those tasks. This article appeared in the September 1942 edition of Radio Retailing
Today magazine less than a year into America's involvement in the War. Even
a militant feminist would probably conclude that, given the state of the world at
the time, it is a very fair assessment and generally exceedingly complimentary.
Note this observation regarding use of women for manufacturing, "Women have made more radio tubes and radio sets than men ever will."
I thought about that while preparing for the restoration of my 1941 Crosley Model
03CB console radio...
 Rhode & Schwarz now has a website area
dedicated to electromagnetic interference
(EMI) debugging and analysis. "EMI debugging in the design phase
will help keep product development on schedule Detecting, analyzing, and correcting
causes of electromagnetic interference (EMI) early in the development process is
the surest way to successfully pass an EMI compliance test and the best way to avoid
redesigns, delays, and added costs late in a project. EMI debugging for unwanted
emissions can start as soon as a circuit is live. Rohde & Schwarz supply multipurpose
equipment including oscilloscopes with leading FFT functions, advanced trigger possibilities
and very low input noise, and spectrum analyzers..."
 Electro-Photonics is a global supplier of
RF &
Microwave components. Their products include SMT hybrid and directional couplers,
wire bondable passive components, mounting tabs, filters, transmission lines, and
very useful test boards for evaluating components (spiral inductors, single-layer
capacitors). The Electro-Photonics team can support your small R&D design requirements
with RF & Microwave test fixtures and save you valuable design and characterization
time. Please take a moment to visit Electro-Photonics' website and see how your
project might benefit.
Monday the 8th
Hugo Gernsback, as I have often pointed out, had a penchant for predicting technology
development and user trends. Decades of researching and publishing articles and
books, inventing electrical and mechanical devices, and creating educational material
enabled a synergistic combination of real-world experience and visionary thinking.
In this 1945 Radio-Craft magazine editorial entitled, "The Radio Alarm," Mr. Gernsback envisioned a form of public
emergency broadcast system that would notify the public of impending and/or in-process
dangers like natural and man-caused disasters, invading armed forces, police alerts,
etc. His idea involved incorporating a special always-on circuit into radios that
would listen for a broadcast tone and then switch the radio on automatically. Of
course in 1945 there would need to be a minute of two allotted for the tubes to
warm up before sending out the actual message. In 1951 the CONELRAD system was put
into operation to alert citizens in the even of a Cold War era invasion or attack,
doing exactly what Gernsback had envisioned, albeit without a the special turn-on
circuit. Then, in 1963 the more familiar Emergency Broadcast System (EBS) took over...
 Innovative Power Products (IPP) has over
30 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband couplers, combiners, resistors, baluns, terminations
and attenuators are fabricated using the latest materials and design tools available,
resulting in unrivaled product performance. Applications in military, medical, industrial
and commercial markets are serviced around the world. Please take a couple minutes
to visit their website and see how IPP can help you today.
 June of this year marks the 10-year anniversary
(albeit a sad one) of the passing of
Bob Pease. Many
of us read his sage insights on analog circuit design for decades; I remember first
seeing his articles in
Electronic Design magazine back in the early 1980s. "Pease Porridge" (nursery rhyme)
was a technical dietary staple, to be ingested once each month when it came via
snail mail. Electronic Design magazine has just released
Bob Pease eBook Vol 1 as "A compendium
of articles from [National
Semiconductor's] legendary electronic design engineer Bob Pease." You'll recognize
the trademark "What's All This..." beginning to titles (some have tried to hijack
it). If for some reason you cannot complete the registration, you might be able
to download directly from
here. This is a great 2016
tribute to Bob - with photos, including of the famous messy cubicle.
 Installing commercial broadcast radio receivers
in cars and trucks was a big deal in the 1930s - even bigger than having one in
your home. Having an ability to receive the popular shortwave bands was a real sign
of success (as was merely owning a car). An advantage to auto radios was not needing
an AC-to-DC rectification circuit like in-home models that required at least one
additional vacuum tube and a hefty transformer - although many people in non-electrified
rural areas had DC radios in their homes as well (the Rural Electrification Act
wasn't passed until 1936). In its service instructions,
Remler suggested to owners that if poor reception was experienced,
the auto should be parked somewhere that a 50-foot secondary aerial couldn't be
deployed. I could locate any examples of restored...
 Christian Block, of Qualcomm, has an interesting
article on the Electronic Design website entitled, "6 Reasons to Move to a Complete Modem-to-Antenna Solution in the Era
of 5G." Says he, "To help tame complexity as 5G continues to expand, network
operators and OEMs should consider complete modem-to-antenna solutions." The short
piece deals with how the smartphone industry is transforming with 5G, how 5G complicates
RF design and finally how to tame 5G RF complexity. As with software, one of the
biggest challenges with adopting new standards is deciding how far backwards in
compatibility the new products need to be...
 Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
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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
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