See Page 1 |
2 |
3 |
4 |
5 | of the March 2020 homepage archives. Friday 13
 While
FM broadcasting (frequency modulation) began in the United States
in the late 1930s, it was not until after World War II and even the Korean
War, in the 1950s, that the major shift to FM took place. It took even longer for
FM to get a foothold in Europe mainly due to the emphasis on rebuilding essential
infrastructure and manufacturing destroyed by the war. As this article points out,
the newer FM radio features allowed it to thwart some of the propaganda efforts
of the Soviets in East Germany who would be stuck in technologies that lag two or
more decades behind the free world even to this day (ain't Communism / Socialism
great?). The "medium-wave band" referenced herein is AM (amplitude modulation),
so replacing dominant radio broadcasting with FM systems would effectively cut off
AM propaganda. FM radios were being produced so inexpensively in the U.S. that they
were very affordable in Europe was well. There is no mention of whether the West
German government subsidized the purchase of FM receivers by citizens...
 During my electronics technician days at
the Westinghouse Electric Company's Oceanic Division in Annapolis,
Maryland, I spent the first couple years building printed circuit boards, wiring
harnesses, and system-level assemblies for U.S. Navy sonar systems. We had some
really slick stuff like towed vehicles with transducer arrays along the sides, nose
cones for smart torpedoes, flow sensors, proximity fuse elements, etc. Exposure
to all that, and the super-smart people that designed it, fuelled my desire to go
to the trouble of earning an engineering degree. One of my tasks for a while was
to build the transducer arrays, which entailed building the hundreds of tiny transducer
elements. One of the phased array acoustic antennas was mounted on each side of
the AN/AQS-14 towed sonar vehicle...
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.
 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
job openings. HR department employees and/or managers of hiring companies are welcome
to submit opportunities for posting at no charge (of course a gratuity will be graciously
accepted). 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 ...
 "Using 3D components on a standardized 2D
microchip manufacturing platform uses up to 100 times less chip space. A scanning
electron microscope micrograph of a
rolled microinductor architecture, approximately 80 micrometers
in diameter and viewed from one end looking inward. Engineers have boosted the performance
of 3D inductor technology by adding as much as three orders of magnitude more induction
to meet the performance demands of modern electronic devices. The microchip inductor
is capable of tens of millitesla-level magnetic induction. Using fully integrated,
self-rolling, magnetic, nanoparticle-filled tubes, the technology ensures a condensed
magnetic field distribution and energy storage in 3D space - all while keeping the
tiny footprint needed to fit on a chip..."
 Please take a few moments to visit the
everythingRF website to see how they can assist
you with your project. everythingRF is a product discovery platform for RF and microwave
products and services. They currently have 227,460 products from more than 1210
companies across 285 categories in their database and enable engineers to search
for them using their customized parametric search tool. Amplifiers, test equipment,
power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers,
power supplies, and everything else. Please visit everythingRF today to see how
they can help you.
 This article
from the January 2020 issue of Air & Space magazine explains why you
remain conscious at 30,000 feet. "We humans need air to breathe, so we do best around
sea level. Airplanes are at their best up high, where the air is thin and smooth.
And therein lies the rub: We invented a machine that thrives where we don't. This
became obvious as soon as engine power increased to a point at which aviators could
reach altitudes where they lost consciousness. At first, fliers coped by filling
tanks with
pressurized oxygen and inhaling the gas through rubber tubes;
later, form-fitting face masks made oxygen delivery more reliable. In many high-flying
light airplanes and military aircraft, oxygen systems and face masks..."
Thursday 12
 Way back in the 1980s while working at Westinghouse
Oceanic Davison in Annapolis, Maryland, an engineer who knew I had recently obtained
a 1941 Crosley Model 03CB console style radio generously gave me his
B&K Dyna-Quik Model 650 Vacuum Tube Tester. It is a very comprehensive
portable tester used by many professional radio and television servicemen. My tester
also had the Model 510 Accessory Socket Panel that added an ability to test 50%
more tube types. One indication that it is one of the later model tube testers is
the inclusion of a transistor testing socket. Unlike testing vacuum tubes, all of
which plugged into sockets to make them easily replaceable, testing a transistor
or solid state diode required unsoldering or clipping the device out of the circuit
and then soldering back in either the verified still good device or a replacement.
It was one of the reasons electronics servicing people eschewed the adoption of
semiconductors...
 "NASA hosted a groundbreaking ceremony for
its upcoming new
Aerospace Communications Facility (ACF) at the agency's Glenn
Research Center in Cleveland on Wednesday, March 4. The Glenn Research Center continues
to develop advanced radio frequency (RF) technology for NASA's aeronautics, science,
and human exploration missions. The new facility will enable Glenn to further advance
communication technology needed to meet the nation's space exploration and aviation
goals, as well as enable commercial and defense communications. The upcoming 54,000
square foot facility will be NASA's premier facility for RF communications technology
research and development. It will allow NASA and commercial partners to develop
faster, higher capacity communications for future missions to the Moon and Mars..."
 There are still a lot of people who
wind their own coils, whether it be for an amateur radio rig or
for work in the lab. I know I've wound many a coil around a drill bit or wooden
dowel. This simple coil winding machine that appeared in a 1931 edition of QST magazine
would be a handy addition to anyone's bag of tricks, especially if find yourself
winding single-layer coils that have a fixed space between the windings. The home
stores like Lowes and Home Depot sell small pieces of oak that would be perfect
for this kind of project. A little stain and a coat of varnish would give it a real
vintage look. Use your soldering iron to burn your name onto the base...
 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!
 Here is an interesting article from the February
2020 issue of High Frequency Electronics magazine entitled, "RF Low Noise Amplifier Technology Landscape Grows More Diverse,"
by Tim Galla. The huge number of semiconductor types now available - SiGe, SiGe
BiCMOS, SiGe:C, GaAs, AlGaAs/GaAs, GaN, AlGaN/GaN, InP, AlInP/InP, SoI, Bi-CMOS,
CNT - is largely responsible for the improvements in LNA performance. I remember
when finding a packaged LNA with 50 Ω ports and a noise figure of less
than 1.0 dB was hard to do. Now, they are commonplace - and at good prices.
It begins: "RF low noise amplifiers (LNAs) fabricated with solid state technology
have been in use for several decades. The early transition to solid state was pioneered
with germanium, has subsequently transitioned to silicon, and has now expanded to
include a wide range of compound III-V semiconductors and new carbon-based materials.
The rapid adoption and advancement of LNA technologies is largely do the growth
and diversification of RF applications, and the specific requirements for these
new and varying use cases. These requirements include the recent focus of greater
linearity..."
 From
1955 to 1961, the TWA-sponsored "Rocket to the Moon" was the E-ticket attraction of
Tomorrowland, the neighborhood of the Disneyland theme park modeled
after a speculative utopian future. Eric Boehm, in the "Letters" section of the
January 2020 issue of Air& Space magazine, submitted the following comment:
"'My Trips to the Moon' (Sept. 2019) and the accommodating photos
really caught my eye, and not because of the big TWA rocket. the fenced-off area
in the foreground was the Disney Flying Circle. Between 1955 and 1966, daily demonstrations
were conducted using control-line model airplanes and gas-powered tether cars. The
photo shows a man in the center with both hands raised. He may be flying two models
at once, which was a regular display feature. There was one employee named Bart
Klapinski who could fly three airplanes simultaneously: One control handle in each
hand and a third in his mouth.
QuinStar Technology designs and manufactures
mm-wave products
for communication, scientific, and test applications along with providing microelectronic
assembly, rapid prototyping, and mass customization. Amplifiers, Oscillators, Switches,
Attenuators, Circulators, Isolators, Filters, Waveguide, Antennas, Phase Shifters,
Transceivers, Mixers, Detectors. QuinStar specializes in cryogenic
amplifiers, circulators, and isolators. Please visit QuinStar today to see how they
can help your project.
Wednesday 11
 When most people are asked to name
prolific inventors, people like Thomas Edison and George Westinghouse,
with 1084 and 361 each, respectively, come to mind - at least for the United States.
As of this writing, Kangguo Cheng of IBM holds the record with 2039 U.S. patents
assigned. Nikola Tesla had about 300 patents. Lee de Forest, the subject of
this 1937 Radio-Craft article, had a little over 180 patents. That still
qualifies as prolific by my estimation. However, there is more to ranking a person's
inventive worth than the number of patents awarded - like how profoundly his or
her invention(s) impacted the world. For instance, Alexander Graham Bell had a mere
18 patents awarded in only his name, with 12 more shared patents. If you look through
Wikipedia's "List of Prolific Inventors," you will see a lot of names with a lot
of patents assigned, but most of those names are probably unfamiliar. Have you noticed
how many of the old patent art looks like..."
 "Step by step, scientists are figuring out
new ways to extend Moore's Law. The latest reveals a path toward integrated circuits
with
two-dimensional transistors. A Rice University scientist and his
collaborators in Taiwan and China reported in Nature today that they have successfully
grown atom-thick sheets of hexagonal boron nitride (hBN) as two-inch diameter crystals
across a wafer. Surprisingly, they achieved the long-sought goal of making perfectly
ordered crystals of hBN, a wide band gap semiconductor, by taking advantage of disorder
among the meandering steps on a copper substrate. The random steps keep the hBN
in line. Set into chips as a dielectric between layers of nanoscale transistors,
wafer-scale hBN would excel in damping electron scattering and trapping that limit
the efficiency of an integrated circuit. But until now, nobody has been able to
make perfectly ordered hBN crystals that are large enough..."
 Anatech Electronics is a privately-held
company founded in 2003 that focuses on supplying quality RF and microwave products
for military, commercial, aerospace and defense, and industrial applications up
to 40 GHz. In their March Product Update, Anatech has introduced
two connectorized and a surface mount duplexer: an n8 / Extended
GSM Band cavity type duplexer with 70 dB isolation, an n30 / WCS Band cavity
type duplexer with 70 dB isolation, and an n2 / PCS Band surface mount ceramic
duplexer with only 3.7 dB insertion loss. Custom RF power directional coupler
designs can be designed and produced when a standard cannot be found, or the requirements
are such that a custom approach is necessary...
 How would you handle evaluating this formula:
a + b * c + d ? The March/April
issue of Discover magazine ran a short article on the history of the
vinculum - that horizontal line which goes between the numerator
and denominator of a fraction (e.g., ¾), and over a number to indicate that
it repeats (e.g., 1/3 = 0.3). Prior
to a century or two ago, it had other common applications as well. The thumbnail
above, which shows many of the vinculum's uses, cuts off the most important part
of the full image that appears in the magazine. The answer to the question is thus:
(a + b) * c + d . Begins the article: "What's a mathematician's favorite bar? A
vinculum, of course. This simple-yet-versatile line holds numbers apart in fractions,
sits atop decimal places when they repeat forever and shows which terms are about
to be square-rooted. Centuries ago, vincula also did the work that parentheses do
today, denoting which terms in an equation should be solved first. But this use
fell out of favor as the printing press gained popularity, since parentheses were
much easier for typesetters..."
Since 1961, MECA Electronics has designed and manufactured an extensive line
of RF & microwave
components for in-building, satellite, radar, radio, telemetry, mobile radio,
aviation & ATC. Attenuators, directional & hybrid couplers, isolators &
circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters &
cables. MECA has long been the 'backbone' of high performance wired and air-interfaced
networks such as in-building applications, satellite communications, radar, radio
communications, telemetry applications, mobile radio, aviation & air traffic
communications.
 "Here's a quick snapshot of where things
currently stand across the industry. Over the last months, there has been a great
amount of global media coverage on the new
coronavirus (COVID-19). The range of data differs from facts and
figures to unrefined conspiracy theories. So before jumping into an investigation
of the effect of coronavirus on distributors of electronic parts, we'll give a short
update. Impact on the Electronics Industry - The electronics industry isn't making
an exemption here. In the most recent weeks almost every maker has given out explanations
on how the coronavirus and initiated quarantine in China is influencing their lead
times. Moreover, numerous organizations have declined to participate in significant
exchange fairs - for example, Embedded World. Coordinators of the Mobile World Congress
in Barcelona even cancelled the event."
 KR
Electronics designs and manufactures high quality filters for both the commercial
and military markets. KR Electronics' line of filters includes lowpass, highpass, bandpass,
bandstop and individually synthesized filters for special applications - both commercial
and military. State of the art computer synthesis, analysis and test methods are
used to meet the most challenging specifications. All common connector types and
package form factors are available. Please visit their website today to see how
they might be of assistance. Products are designed and manufactured in the USA.
Tuesday 10
 What got my attention in this 1955 Radio &
Television News magazine article was the "picture-on-the-wall" concept being predicted by General Electric
(G-E) engineers, based on its light-amplifying phosphor invention. Determining exactly
how the device works is difficult based on the information given, but it appears
that the ultraviolet light source which is being amplified is projected onto the
surface of the amplifying substrate, and then an exact duplicate of the image is
reemitted toward the viewer. The conceptual drawing of a large screen hanging on
the wall is most likely driven by a UV projector located near the ceiling, akin
to how the large screen home theaters popular in the early 2000s worked (though
with no amplification by the screen). Obviously the scheme never came to commercial
fruition since such systems were never widely used. Other anticipated applications
included x-ray fluoroscopy, photography, "seeing-in-the-dark" (aka infrared
night vision) devices...
 "MIT researchers have invented a way to integrate
'breadboards' - flat platforms widely used for electronics prototyping - directly
onto physical products. The aim is to provide a faster, easier way to test circuit
functions and user interactions with products such as smart devices and flexible
electronics. Breadboards are rectangular boards with arrays of pinholes drilled
into the surface. Many of the holes have metal connections and contact points between
them. Engineers can plug components of electronic systems - from basic circuits
to full computer processors - into the pinholes where they want them to connect.
Then, they can rapidly test, rearrange, and retest the components as needed..."
 This being about coffee, it is engineering-related
and thus qualifies as a relevant news item. "Just when the 'greens' thought they'd
won over the giant coffee industry and Starbucks, in particular, with its
reusable coffee cup campaign, to rid the world of single-use plastics,
along came the coronavirus. According to articles on several news sites, Starbucks
has banned customers from bringing their reusable cups into the stores for refills
because of the pandemic. ...It's for that reason that health department regulations
have typically prohibited people from bringing their own cups and glasses to dining
establishments. It's why buffets require people to get a clean plate each time they
go back for seconds and thirds..."
 The
term "modern" in the title of any book or article never has set right with me because
it is utterly ambiguous about the era to which "modern" refers. Sure, it sounds
good at the time, but when applied to this 1966 QST magazine article, "modern"
should be replaced with "four-decade-old." However, in this case the content is
still relevant even thought it was written so long ago (or else I would not be reproducing
it here). It may well have been most people's first exposure to
elliptical (Cauer) filters. As you might expect, the rigorous,
headache-inducing mathematics is omitted, but the article does give an example of
implementing an audio frequency bandpass filter by cascading a lowpass filter and
a highpass filter. If you are familiar with filter design, you know that because
of phasing and inband impedance mismatch issues you cannot simply butt the two together
to yield an equivalent bandpass filter. In fact, the author found it necessary to
insert a 13 dB attenuator between them in order to get acceptable performance...
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.
 Leaky coaxial cables are not always a bad
thing. "Radio Frequency Systems (RFS) has released new
radiating cables for delivering 5G connectivity in tunnels. The
latest patented Radiaflex cable supports all mission critical and commercial wireless
services, working in all 3GPP bands up to 3.8 GHz. Using RFS's unique mode suppression
technology the ultra-broadband cable works with no stop-bands to support current
and future frequency needs, protecting customer investment from spectrum re-banding
and preempting new generation requirements for years to come. The cable is technology
agnostic, giving complete flexibility to customers, supporting mixed configurations
and multi-operator or shared infrastructure deployments..."
 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. Take a couple minutes to visit their website and see how
IPP can help you today.
Monday 9
 I was around and doing computers in the 1980s,
but do not remember this. The aptly named Interesting Engineering website has this
piece on how back in the early days of personal computing, some radio stations would
broadcast over the air digital
code for video games. That was when 16-color, 640x480-pixel CGA
CRT displays were considered bleeding edge. A video contains the complete audio
transmission, which will remind you of the times of trying to sign onto AOL or
Compuserve
with your 1200 baud telephone modem when a connection took 5 minutes to
complete because of too many users and too few open lines. The little dude in the
"Manic Miner" looks like one of the Mario Brothers...
 Lots
of new titles are included this month.
Engineering whitepapers,
pamphlets, books, magazines, and chapter examples listed here are a small sample
of a lot of new items that are offered for FREE through TradePub. The publishers
make them available to qualifying people as a promotional campaign for their full
line of offerings. Free e-books like "Maximizing LinkedIn for Business" and "20
Questions You Should Never Ask in an Interview" are examples. Magazine titles include
Microwave Engineering Europe, Electronic Design, and Microwave Product Digest...
 Pasternack, an Infinite Electronics brand
and a leading provider of RF, microwave and millimeter wave products, has expanded
its offering of
mmWave waveguide antennas to address the growing number of 5G
and other high-frequency applications. Pasternack's line of millimeter-wave, waveguide
antennas has added 54 new models and now covers broad operating frequency ranges
from 1.7 to 220 GHz, provides nominal gain ranging from 0 dBi to 40 dBi,
and features a variety of different waveguide sizes. Five new categories of high
frequency waveguide antennas are now available to address point-to-point and point-to-multi-point
wireless applications, including probe waveguide antennas to 170 GHz with 6.5 dBi
of gain...
 Axiom Test Equipment allows you to
rent or
buy test equipment,
repair
test equipment, or sell or trade test equipment. They are committed to providing
superior customer service and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today!
 Here is a useful interactive map of worldwide
reported coronaviruses (COVID-19), compliments of Johns Hopkins. As of this screen capture
there have been reported (important distinction) 111,228 cases with 3,892 deaths
(3.50%) and 62,369 people who have recovered (56.1%), leaving 40.4% undetermined.
While I do believe the media and governments are over-hyping this by feeding and
exploiting fear, it is useful to see how effectively the people of the world can
work together in an emergency when motivated. As usual, the knowledgeable folks
get the job done while politicians and TV stars expose their collective ignorance
and egos. Maybe there are politivirus and mediavirus strains mutating out there
somewhere to spare the world some misery.
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 8
 As with my hundreds of previous
science and engineering-themed crossword puzzles, this one for
March 8, 2020, contains only clues and terms associated with engineering, science,
physical, astronomy, mathematics, chemistry, etc., which I have built up over nearly
two decades. Many new words and company names have been added that had not even
been created when I started in the year 2002. You will never find a word taxing
your knowledge of a numbnut soap opera star or the name of some obscure village
in the Andes mountains. You might, however, encounter the name of a movie star like
Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons which,
if you don't already know, might surprise you.
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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