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 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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