See Page 1 |
2 |
3 |
4 | of the June 2020 homepage archives.
Friday 19
Many topics of the
electronics-themed comics which appeared in Radio-Craft were suggested by the
magazine's readers. Staff artists like Frank Beaven turned those suggestions into
cartoons. For a while there was a special feature called "Radio Term Illustrated"
where, as the name suggests, terms like "Signal Generator" and "High Potential"
are rendered in farcical form. These four comics, two of each type, appeared in
a May 1947 issue of Radio-Craft. I have to admit that even with my familiarity with
vintage electronics memes I do not get the Television "Organ" comic (yes, I understand
the organ grinder, but not how it applies to TV).
"The charge of a single electron, e, is defined
as the basic unit of electric charge. Because electrons - the subatomic particles
that carry electricity - are elementary particles and cannot be split,
fractions of electronic charge are not normally encountered. Despite this, researchers
at the University of Illinois at Urbana-Champaign have recently observed the signature
of fractional charges ranging from e/4 to 2e/3 in exotic materials known as topological
crystalline insulators. The team of researchers, led by mechanical science and engineering
professor Gaurav Bahl and physics professor Taylor Hughes, has been using ultra
high frequency electric circuits to study topological insulators since 2017..."
Component Engineering challenges often require
finding a "commonly available solution," for a specific application that meet broad,
often conflicting requirements, determined by colleagues in electronics. Assuming
knowledge of standards like
RG cables and widely available solutions, our expertise can be useful when those
will not work. ConductRF can provide options for higher frequency, lower loss, greater
mechanical integrity and more. When working in tight spaces, try these new RF cable
options available exclusively from ConductRF. Costs & Lead Times Maintained
Because these new cables are derived from older standards, ConductRF has been able
to make minor changes to existing standard connectors. Changing crimp ferrules or
re-purposing designs for other cables has allowed us to make many standard connectors
available for producing assemblies...
A few years ago, RF Cafe visitor Cornell
Drentea, KW7CD, submitted a short paper entitled, "Who Invented Radar?"
I just updated the page to fix broken hyperlinks and figured it is worth posting
again. I won't spoil his conclusion / assertion by telling you here. Mr. Drentea
begins: "Whenever thinking of Radio, we usually think of one man: Guglielmo Marconi.
Radar, on the other hand resulted from the work of many men. In 1793, the Italian
scientist Lazzaro Spallanzani, a professor at Padua University studied the ability
of blind bats to navigate using ultra sound. He observed that bats flew well in
the dark without the aid of vision. He then designed a unique experiment to demonstrate
the use of the bat's ears and concluded that a bat would become disoriented without
its hearing. He concluded that the bats produced a continuous train of sound pulses
and suggested that the rate of these pulses increased as a bat approached objects.
This was not proven until..."
Look deeper into those shiny front-page "sheet"
specs - and search out the truly relevant data - to see if the part really is the
best option for your application. Tejaswini Anand "All
that Glitters Is Not Gold: Interpreting Datasheet Data When Selecting Parts"
"Application engineers often repeatedly answer the same questions from different
customers, especially queries related to choosing parts in their application. One
mistake we see in part selection happening time and time again is that the customers
become over enamored by what I like to call 'the sheet' in data sheets. I'm talking
about the shiny, glittery, sexy specs. 'Wow! That ADC has a high SNR!' This is the
story of one such customer who was impressed with one analog-to-digital converter's
(ADC) high signal-to-noise (SNR) but who forgot to consider other important datasheet
specs. We will also address common mistakes and how to choose the right parts for
your application."
Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated 4-port vector network analyzer
(VNA) calibrator, between- and in-series connector adaptors, attenuators, terminations,
DC blocks, torque wrenches, test probes & probe positioner. Special test fixtures
for calibration and multicoax cable assemblies. Frequency ranges from DC through
110 GHz. Please contact Withwave today to see how they can help your project
succeed.
Thursday 18
Center of Telecommunication Technologies
is proud to announce immediate availability of their
MLinkPlanner 2.0 wireless network software simulation tool for modeling microwave
point-to-point (PtP) and point-to-multipoint (PtMP) links. The new version is free
for current MLinkPlanner users. MLinkPlanner was created by engineers with many
years of experience in designing microwave links, from single hop access links to
high-power long-haul trunk lines. MLinkPlanner has demonstrated its effectiveness
in designing many links that are operating successfully in various climate zones
and topographical conditions from plains and marshlands to highlands. Special focus
was placed on devising a convenient user interface, the incorporation of adaptable
and easy to use link path profiles in the design process...
Paul Wade, W1GHZ, has a great article entitled,
"Focusing
a Parabolic Disk," in the June 2020 issue of the ARRL's QST magazine (p54).
It discusses how to properly position a feed horn at the focus of a parabolic antenna
dish, and presents plots of how various misalignments affects the signal quality.
The motivation was determining how sensitive feed horn placement based on a near
field test setup affects performance in the far field. Equations for the plots are
not provided; however, Mr. Wade does include the
Rayleigh distance
(DR) formula for antennas of DR = 2D2/λ,
which is the transition distance from
near field to far field
- the Fresnel and Fraunhofer regions, respectively. Unfortunately, you need an ARRL
member login to access the article, but if you don't have one, find a nearby Ham
and ask to borrow his hard copy. BTW, the June 2020 cover has to be the ugliest
thing ever published on QST.
RF Cafe visitor Mike M. sent this very
interesting note after reading this "Frequency
Modulation Fundamentals" article: Again, you hit it out of the ballpark, Kirt!
Great article out of QST. Absolutely accurate to credit "The Old Man" Edwin Armstrong
for the invention/development of FM and much more, plus the work of Dan Noble, who
worked with the Connecticut State Police and Motorola as Director of Research. Also
many, many others. Some that have never been properly credited. Guys like Bob Morris,
W2LV and Frank Gunther, W2ALS. They were both interviewed by Ken Burns for "Empire
of the Air". I was fortunate enough to talk to both of these guys after I got my
Tech license in 1970. My immediate supervisor/mentor from 1972 until he retired
in ~1990, was George. He was a superb mentor, who espoused the best engineering
methods and as he would say " the price of success is constant vigilance." George
had worked for Armstrong at the pioneering FM station, W2XMN in the late 40's and
early 50's. George had several stories about working for "The Old Man..."
Ralph Prigge, of
Alaris USA, wrote to request that his
company be added to the list of companies on the RF Cafe Antenna Vendors page. Alaris
USA is an organization based in Maine to sell products of COJOT, mWAVE and Alaris
Antennas to their customers in the USA. All are sister companies owned by Alaris
Holdings Limited (formerly Poynting Antennas) headquartered in South Africa. They
design, manufacture and distribute antenna products for the global defense, homeland
security and specialized antenna market sectors, including international electronic
warfare (EW) system houses and also include semi- and governmental organizations.
Alaris USA is proud to provide our American customers specialized military and defense
products including EMC, tactical communications, vehicle-mounted, fixed site, switched
beam, direction finding, and mission adaptive antennas. Please check Alaris USA
out today if you have antenna needs.
Now
that the wonder material graphene and the wonder wireless communications scheme
of 5G has had their respective heydays, much attention is being given to quantum
computing and quantum-tunnel transistors. "Quantum," which already had its own heyday
back in early last century, is in vogue again - like wide ties, big-framed eyeglasses,
and miniskirts. Lee Goldberg has a piece entitled "Are
Quantum-Tunnel Transistors Real, and What Do They Mean for Power Tech?" posted
over on the Electronic Design website in case you are interested in learning
about the latest happenings in the field of quantum-tunnel transistors. They actually
have nothing to do with quantum computers, and get their name due to tunneling effects
(a la the familiar tunnel diode) that are exploited in this new "Bizen" phenomena
that is being touted as a replacement for CMOS ICs. Time will tell how accurate
the prediction is, as with the recently mentioned
Wamoscope.
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.
Wednesday 17
Robert Balin created many quizzes for
Popular Electronics magazine during the 1960s and 1970s. Topics included series
circuits, electrochemistry, electronic analogy, electronic coupling, electronics
analogy, audio, electronic units, capacitor circuits, AC circuit theory, magnetic
phenomena, electronics geography, electronic noise, plugs and jacks, electronic
switching, diodes, and many more. This "Electronics
Physics Quiz" is the 59th that I have posted. It challenges you to name the
effects that were first noticed as the result of unexpected actions during laboratory
experiments. Many of the names, as you might expect, eponymously honor their progenitors. My
score was 80%.
"Upgrades include a mode for use while wearing
night-vision goggles, and a stealth mode that disables LTE and mutes all RF broadcasting.
The handset has undergone a series of changes to make it a piece of military-grade
tech. In addition to being packed into a case that looks like it could withstand
a nuke, the S20 TE features
DualDAR architecture that secures data with two layers of encryption and is
based on NSA standards. With communications being a vital element of a field operative's
work, Samsung says the S20 TE comes with pre-configured software to support tactical
radios and mission-critical devices through the use of Private SIM, 5G, Wi-Fi 6
and CBRS (Citizens Broadband Radio Service) -- a band of radio-frequency spectrum
from 3.5 to 3.7 GHz..."
Just in
time for the birthday of vacuum tube pioneer Sir William Crookes, Lou Frenzel has
an article entitled "Tubes:
Luckily, They're Still Around" on the Microwaves & RF website.
"As Noah said to his family after dinner, 'Those unicorn steaks were excellent!'" "So,
unicorns are gone for good. But not vacuum tubes. It doesn't seem that tubes will
ever disappear completely - they're still with us and that's a good thing. I was
reminded of that several times over the past weeks. For example, I was scanning
the ads for a high-power ham-radio amplifier. Most of the popular transceivers top
out at about 100 W. For good long-distance (DX) communications around the world
on the high frequency bands (3 to 30 MHz), more power is desired. A number of companies
make accessory power amps to boost power level to the FCC legal limit of 1500 W.
Both transistor and tube models are available to choose from. The solid-state amps
use multiple RF MOSFETs to get to levels of 500 to 1000 W. These are very expensive..."
The world's first electric wristwatch went
on sale on January 3, 1957 - the Ventura model, by Hamilton Electric, and it retailed
for $200. I use the event as the theme of the RF Cafe logo for that day in history.
Unlike today's electric watches which use a crystal for timing, the early watches
used a pulsed motor to energize the balance wheel coil, in place of a mainspring
and an escapement mechanism. Some "atomic" wristwatches today like the Casio Waveceptor
(<$40) use the WWV signals from Boulder, Colorado, to synchronize the time with
world standards. The watch shown in this article from the February 1958 edition
of Radio-Electronics magazine is a model 500, which you can find more detail about
on the Unique Watch Guide website...
Joe Cahak, owner of Sunshine Design Engineering
Services, has submitted another fine article for posting here. Joe has many years
of automated RF testing experience to leverage when writing this paper on making
measurements with scattering parameters (S-parameters)
involved. He begins, "In many RF and Microwave measurements the S-Parameters are
typically expressed in dB (decibels) Magnitude units and Degrees in the polar coordinate
system. Network and Vector Network Analyzers and Spectrum Analyzers all measure
with voltage ratio measurements, so to convert to dB in terms of volts we must use
the following equation. The Spectrum Analyzer is a frequency discriminating detector
that detects the voltage for the signal. It will give the amplitude of signal as
a function of frequency. It is scalar in measurement dimension magnitude vs. frequency.
Displayed units are typically expressed in units of power (dBm). The Vector Network
Analyzer measures complex magnitude and angle of RF signals vs. frequency. By using
reference signals to calibrate the test system response and setting up a reference
frame for the measurements, the instrument can measure the amplitude and phase angle
of the AC-RF signal for each frequency it is tuned to. Displayed units are typically
expressed..."
Qorvo / Custom MMIC is a
fabless RF and microwave MMIC
designer entrusted by government and defense industry OEMs. Custom and off-the-shelf
products include switches, phase shifters, attenuators, mixers and multipliers,
and low noise, low phase noise, and distributed amplifiers. From next-generation
long range military radar systems, to advanced aerospace and space-qualified satellite
communications, microwave signal chains are being pushed to new limits - and no
one understands this more than Custom MMIC. Please contact Qorvo / Custom MMIC today
to see how they use their modern engineering, testing and packaging facility to
help your project.
Tuesday 16
According to the Wikipedia entry, Cannon
Electric Company introduced the now-familiar D-Sub (D-subminiature)
connector format in 1952. This advertisement in a 1954 issue of Radio & Television
News magazine is the first one I recall seeing. D-Sub connectors were a really big
deal back in the 1980s when personal computers (PCs) first appeared. CRT monitors
used them, printers used them, scanners used them, network interfaces used them,
mice and keyboards used them (those that didn't use PS/2 connectors, which were
an invention of IBM for their Personal System 2 computers). Nowadays the USB (Universal
Serial Bus) and HDMI (High-Definition Multimedia Interface ) connectors have replaced
most D-Subs in the computer cable realm. Of course with everything going wireless,
connectors and cables of all sorts are rapidly disappearing except those used for
charging...
"Official talks on construction and operation
of a new TSMC semiconductor
chip manufacturing fab the in U.S. is promising but riddled with political and
technical intrigue. Will the news of a new semiconductor fab on U.S. soil be a boost
to the economy and technological stability or is it merely a fanciful political
scheme? To answer that question, let's start with the news that has created so much
discussion in the electronics space. Recently, the Taiwan Semiconductor Manufacturing
Company (TSMC) announced its intention to build and operate an advanced 5nm semiconductor
fab in the U.S. state of Arizona. TSMC, headquartered in Taiwan, is the largest
chip manufacturer in the world. The company currently operates a fab in Camas, Washington
and design centers in both Austin, Texas and San Jose, California. The Arizona facility
would be TSMC's second manufacturing site..."
Yeah, I thought the same thing... a "Wamoscope?"
Was it produced by the Wham-O toy company that makes the Hula Hoop, the Frisbee,
the Super Ball, and Silly String? Wham-O was founded in 1948, and this article appeared
in a 1956 edition of Radio & Television News magazine, so why not? Actually,
Wamoscope is derived from "WAve-MOdulated oscilloSCOPE." Developed by Sylvania Electric
Products, it combined a traveling-wave tube with a cathode ray tube in single enclosure.
That enabled microwave signals to be fed directly to the CRT for amplifications
and processing. Evidently the idea did not catch on since the market was never filled
with Wamoscope sets. A brochure for Sylvania's 6762 Wamoscope is shown at the bottom
of the page...
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 ...
If 5G began life as and still does to many
people remain a nebulous concept, then the definition of 6G is really up for grabs.
This article on the EDN website by Jessy Cavazos, entitled "Aspects
of 6G That Will Matter to Wireless Design Engineers," is one of the first attempts
I've seen to explain it. Here is her summation: "In addition to the next-level evolution
in automated driving and smart manufacturing, 6G will enable innovative applications
by combining sensing, imaging, and precise timing with mobility and truly leveraging
artificial intelligence (AI) and intelligent networks. Further integrating communications
technologies into society, 6G technology will bring mixed reality experiences and
telepresence to life, while playing a pivotal role in achieving global sustainability,
improving society, and increasing productivity across industries."
Nova Microwave is a leader in technically differentiated
electronic and radio frequency Ferrite Circulators and Isolators that connect, protect and control
critical commercial and military wireless telecommunications systems. Our staff
is dedicated to research and development of standard and custom design quality Ferrite
Circulators and Isolators from 380 MHz to 26.5 GHz. Available in single
or multi-junction topographies, the Nova Microwave product line of is specifically
designed for use in varied environmental and temperature extremes.
Monday 15
This is another example of one of those
advertisements you likely would not see in a modern electronics magazine. There
is nothing fundamentally problematic about its content or message, but politically
correct standards would condemn any depiction of a woman expressing such excessive
appreciation for a man's efforts. It might, after all, convey the idea that all
television antenna servicemen should expect such treatment from all women. It also
implies that only men can be TV antenna servicemen / servicepersons. If that sounds
nutty, well, what can I say. It's the world we live in as evidenced by news items
of late. Keep firmly in mind that what is accepted as a social norm today might
be considered to be a crime in a few decades, so exercise caution in all you do
in the presence of witnesses be it written, videoed, spoken, or acted out...
"Silicon
solar cells folded into spheres hint at solar power's flexibility in even small
devices. Flat solar panels still face big limitations when it comes to making the
most of the available sunlight each day. A new spherical solar cell design aims
to boost solar power harvesting potential from nearly every angle without requiring
expensive moving parts to keep tracking the sun's apparent movement across the sky.
The spherical solar cell prototype designed by Saudi researchers is a tiny blue
sphere that a person can easily hold in one hand like a ping pong ball. Indoor experiments
with a solar simulator lamp have already shown that it can achieve between 15% and
100% more power output compared with a flat solar cell..."
RF Cafe visitor Dave H. wrote to offer the
following additional information about the
history of mobile radio communications. It is fairly extensive, so it is posted
at the bottom of the page. "I liked the article about Don Wallace and his car to
home radio. I knew that in Detroit, the police had attempted to have car to car
transmissions. They were not overly successful however. They did implement a station
to car, 1 way transmission. I discovered the facts about the Detroit police radios
while researching a paper that I wrote entitled: 'SAW Filters : The Unsung Heroes
of the Cell Phone Revolution.' Did you know that that the phone developed by Martin
Cooper while at Motorola, circa 1973, had a filter board that measured 10 inches
by about 1 inch? That would be a tad hard to find..."
This is the first of a two-part series on
the move of the
WWV transmitter stations operated by the National Bureau of Standards (now called
National Institute of Standards and Technology) from Greenbelt, Maryland, to Boulder,
Colorado. WWV Part II appeared in the February 1967 edition of the ARRL's QST
magazine. WWV began transmitting time / frequency standards in 1920 in order to
provide a means for remote stations and laboratories to calibrate local standards
that would prevent transmitting stations from interfering with each other. Although
most people don't realize it, the 60 kHz signal that their 'atomic' clocks
and watches use to self-adjust time emanates from the WWVB antenna in Boulder. This
first installment of the article discusses the history and rationale for relocating
the WWV facility to a new location. The second part gets into the technical aspects...
When an industry-leading provider of stratospheric
communications platforms first called on
TRIAD RF Systems, they were initially looking to gain an incremental wireless
communications range boost. What they achieved instead was a mission that went from
an underwhelming link performance test to an incredible long-range success in under
5 minutes. The Challenge: Filling the capability gap between aircraft, drones and
satellites, this industry-leading platform designer and manufacturer delivers solutions
for communications, data relay, and intelligence, surveillance, and recognizance
(ISR) applications to space agencies, the military, communications providers, and
many other commercial applications. The customer simulated that the link distance
without a TRIAD power amplifier would be approximately 100 miles. However, at a
distance of 75 miles away from the base station, the link started to cut out, and
all communication was lost...
PCB Directory is the largest directory of
Printed Circuit Board (PCB) Manufacturers,
Assembly houses, and Design Services on the Internet. We have listed the leading
printed circuit board manufacturers around the world and made them searchable by
their capabilities - Number of laminates used, Board thicknesses supported, Number
of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical
location (U.S., China), kinds of services (manufacturing, fabrication, assembly,
prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.
Sunday 14
Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed
crossword puzzle using only words from my custom-created lexicon related to
engineering, science, mathematics, chemistry, physics, astronomy, etc. In this crossword
for June 14th you will never find among the words names of politicians, mountain
ranges, exotic foods or plants, movie stars, or anything of the sort. You might,
however, see someone or something in the exclusion list who or that is directly
related to this puzzle's theme, such as Hedy Lamarr or the Bikini Atoll, respectively.
Enjoy!
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