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 If you are like me, you spend a lot of time
reading articles from technical magazines. Sometimes I read the entire article,
but usually I just scan the text for highlights and look at the schematics,
block diagrams, and charts / graphs. Often, I want to go back and find an article
but cannot recall where I saw it. A Google search will usually eventually reveal
a hyperlink to the article, but a lot of times it takes a lot of digging. Since
my key interests are not necessarily the same as RF Cafe visitors, an attempt
will be made to catalog all of them. If there is a magazine not included here
that you would like me to include in the list, please send me an e-mail and
I will try to incorporate its articles, too.
Aerospace & Defense | EDN | Electronic Design |
High Frequency Electronics |
IEEE Spectrum | Microwave
Journal | Microwaves & RF |
Microwave Product Digest |
 Many of us are familiar with
the math behind the Smith chart. Some have written spreadsheets and software
for creating Smith charts, if only for the satisfaction of being able to do
so. It really is quite simple (complex, actually - get it?) to do, but as
with most things a genius mind (i.e.,
Phillip Smith) was
needed to think of doing it in the first place. John Dunn, a very smart guy
in his own right, posted a good primer on the subject on the EDN
website. If you are new to the Smith chart or just want to do a refresh, then
surf on over to read his article, and maybe click on the three related links
at the bottom for more info.
 Here's a trip down Memory (640 kB)
Lane for those of us around during the early PC days, using MS−DOS. EDN
magazine has been running their column "Tales from the Cube"
(a take-off of the equally long ago "Tales from the Crypt" TV show) where readers
submit sagas of (usually) troubleshooting experiences. Most often the problem
is the result of an intermittent event or of human error (pronounced "stupidity").
This is a case of the latter. If you fondly recall the times when 256-color
VGA
CRT monitors,
3½" floppy disks, 20 MB hard drives, and an
i80287 math coprocessor
were to die for, when you were deemed a computer expert if you could write batch
files, and half your computer's CPU power was not consumed by antivirus programs
(no WWW, just
Kermit for local
net access), then you might like this "The Mysterious
MS-DOS Reboot" anecdote by Robert Yankowitz. Enjoy!
 Whenever I see John Dunn's name I think
of the English poet John
Donne, but that's my problem. Mr. Dunn wrote an article for EDN magazine
entitled, "What's
the Difference Between EMF and Voltage?" He begins: "I once read this very
strongly-written essay about the difference between electromotive force (EMF)
and voltage. The author seemed like he was on some kind of holy crusade and
was intensely determined to set his readers straight on fundamental truths that
were NOT to be dismissed by infidels. I read his words, but for all of the vitriol,
I didn't understand him at all. Recently, I decided to take a closer look at
the issue. EMF is given in units of joules per coulomb. The frame of reference
for this definition is for any device that uses a non-electrical source of energy
to impart electrical energy to a unit of charge, which if given the chance,
will flow somewhere..."
 James Mazzei has a good primer entitled,
"A
Reminder: Pay Attention to Harry Nyquist and Claude Shannon," on information
theory at the Electronic Design website, where he admonishes that,
"Many CIOs, CTOs, and architects tend to forget this telecommunications throughput
issue." Further, "It's a very easy and normal thing to focus on the principal
characteristics of the principal components of a communications system or link,
and regard other items and issues as peripheral and not so important. That it
has happened a surprising amount with satellite communications links, especially
remote mobile ones, is the reason for this missive. Here's a hypothetical situation.
You are a soldier. You're deployed in a mountainous area of the Middle East,
carrying an older Intelsat satellite terminal for immediate access back to headquarters,
and the headquarters has leased a 72-MHz transponder..."
 "As the EV market grows, so does demand
for robust magnetic field sensors within these vehicles. Stray magnetic fields
may diminish the accuracy of these sensors, though, which is where active stray-field
compensation comes to the rescue." So begins Frederik Berstecher in his
article entitled,
Overcome Stray Magnetic Fields with Active Stray-Field Compensation, posted
on the Electronic Design website. Continuing, "The electric-vehicle
market continues on a serious upswing: Allied Market Research forecasts show
it will reach $802.81B by 2027, up from $162.34B in 2019
[can they really estimate to 5 significant digits?
- KRB]. Such growth also pushes the need for additional magnetic field
sensors within these vehicles for position detection. The sensors are robust
enough to withstand a variety of harsh environmental conditions, temperatures,
vibrations..."
 In case you haven't heard yet, SAGE
Millimeter, which was formerly
SAGE Laboratories (if I recall correctly), is as of year 2020 called
Eravant. mm-wave waveguide components
are always très-cool in appearance, and there are a bunch of them shown on the
High Frequency Electronics website. Seeing them arrayed under special
lighting in an exhibit at a trade show reminds you of a jewelry store display
case. The precision machining and often polished surfaces make them gleam. Here
is a great idea (IHMO) for the marketeers at one of these mm-wave companies:
Create a children's play set a la LEGOs consisting of plug-together waveguide
components molded to look like common parts. Many of them could be full-size
if modeled after higher frequency lines. Rigid and flexible, rectangular and
round waveguide, antennas, towers, couplers and amplifiers, circulators, rat
races, and many other shapes in bright colors would make for some awesome-looking
projects and just might produce some of the world's next RF / microwave / millimeterwave
engineer. Maybe call them WEGO (WavEGuideO). Or, create a breakfast cereal using
those shapes and call them Engineerios (Cheerios). You're welcome.
 It has been a while since I saw an article
discussing stability circles for amplifier design. Ain Rehman has one posted
on the High Frequency Electronics website entitled, "Understanding
Stability Circles." Even in the age of computer design and optimization
for just about everything, it always help to have a basic understanding of what
the result should look like as well as what affects the result. He begins: "Stability
circles are a tool, used to examine and analyze the stability of an amplifier
(in the case under discussion) using a graphical technique, with the help of
a Smith Chart. (Note: A free, demo version of smith chart software is available
on the web from Fritz Dellsperger). This monograph presents the stability circle
tool for engineers. It is understood that many CAD programs can generate these,
but it is always useful to understand the stability circle on an intuitive level
as a good engineering practice..."
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