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Today in Science History -
 An excellent short history on "The Discovery of Radio Waves" was published by
George Steber in the Jan/Feb 2019 issue of Nuts & Volts magazine. "When
the concept of electromagnetic waves was first proposed around 1864, it was met
with great skepticism. As a result, the idea languished for a long time. This is
understandable since the foundations of the theory were complex and the conceptual
ideas were at odds with physical thinking. It took several decades for a handful
of dedicated persons - infatuated with the mysteries of electricity and magnetism
- to finally put the theory on a solid footing …"
Improving Object Detection with
Low-Bandwidth Radar
 "Researchers at Tel Aviv University have designed
a new type of radar ranging system that requires virtually no bandwidth to operate
successfully. This new method does not have the bandwidth limitations of traditional
methods, meaning it can be used in a vast array of different applications - particularly
when it comes to the automotive industry Traditionally,
radar resolution was believed to be proportional
the bandwidth use. Essentially, the wider available range of frequencies, the better
the radar will be at detecting objects in its path. The new method devised by researchers
seeks to change all that …"
 EE Times has an interesting piece
on their website regarding how modern engineering methods might be used to restore
the fire-ravaged
Notre−Dame church to its original condition.
Some interesting observations are made, one regarding how cleaning and replacing
stained glass tiles will affect lighting to the 13th century conditions vs. as it
was two weeks ago. Another suggests ultrasonic analysis of mortar joints to structural
integrity, use of drone photos and laser measurement to construct a detailed 3D
model of the building for work planning. It also suggests a call to social media
for obtain as many of the millions of photographs taken by visitors from all perspectives
and times of day for recreating damaged or destroyed components.
 If you happen to be Estonian, you might think
of something entirely different than most of us do when we hear the word "getter."
In fact, you probably capitalize the word since it is the name of a pop singer from
your country, Getter Jaani. If you are a child living in Japan, you would probably
think of Getter Robo, an anime from a popular cartoon series. I, and I dare say
just about everyone else that visits RF Cafe, knows getter as that silvery deposit
(typically barium) that resides inside vacuum tubes for the purpose of helping to
maintain the vacuum and to absorb pesky random molecules that might otherwise cause
electrical noise in the circuit. This article from a 1958 edition of Radio-Electronics
discusses the purpose of getter. BTW, I had never heard of either of the other two
Getters due to OGS (old guy syndrome) …
 Rohde & Schwarz has published a white
paper entitled, "The Future of EMC Test Laboratories," which addresses
the increasingly difficult to meet EMI and EMC certification requirements in today's
extremely crowded electromagnetic spectrum. "The growing complexity of electronic
devices within both military and commercial products has lead to a significant increase
in failure rate of EMC conformance testing. Product design cycle times continue
to decrease due to competitive pressure in the market. Product design companies
are spending more money on multiple iterations of product EMI compliance testing
at EMC test laboratories, and this comes at a significant …"
 Res-Net Microwave has a complete line of
precision RF & microwave components including attenuators, terminations,
resistors, and diode detectors for commercial, military, and space applications.
Products range from the small flange type to large 2,000 watt connectorized power
attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo
etch and laser trim capability. Please check out Res-Net Microwave's website to
see how they can help with your current project ...
 Since 2000, I have been creating custom
technology-themed crossword puzzles for the brain-exercising benefit and pleasure
of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or
not this type of mental challenge helps keep your gray matter from atrophying in
old age, but it certainly helps maintain your vocabulary and cognitive skills at
all ages. A database of thousands of words has been built up over the years and
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc. 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 …
 There's not a much better way to finish up
a hard week at the office than reading a new episode of John T. Frye's "Mac's
Radio Service Shop." Mac McGregor and his trusty sidekick technician Barney tackle
nearly every issue associated with an electronics sales and service establishment
back in the heyday of radios and televisions. You might recognize the title of "Pride
and Prejudice" as being borrowed from Jane Austin's classic, which, to summarize,
deals with, well, pride and prejudice based on one's social status, and how it results
in lost opportunities. To be honest, I have not read the book (Melanie's the designated
book reader in our household) but I did see the movie version starring Keira Knightly.
Anywho, you'll need to read the second half of the story to get to the actual pride
and prejudice part …
 This is part 3 of a 5-part series of articles
by Farron Dacus. You can access this and the previous two articles and "Noise and its Shaping in Ultra-Low-Noise Synthesizer
Design" on the MW&RF website. "This third part in our low-noise synthesizer
design series is the medium-length online version. In print are the abridged versions,
while full-length versions are available at
www.longwingtech.com.
Part 1 (Dec. 2018) covered basic design for functionality and stability. Part 2
(Feb. 2019) covered the many noise sources in the synthesizer outside of the actual
synthesizer IC. This third article looks into synthesizer IC noise, the closed-loop
shaping of noises, and related issues such as optimum bandwidth. Here, a key metric
for characterizing synthesizer IC noise is developed. This material also leads directly
to analysis of optimum loop bandwidth …"
 Antennas have been deployed in difficult environments
using many ingenious methods over the years both by professionals and amateurs.
The process typically involves first propelling a lightweight string or wire across
and/or up to a supporting structure (a tower, tree, building, whatever) and then
using that lead line to draw the antenna and its accompanying coaxial or twin lead
cable into its final position. Sometimes simply tying a line to a rock and tossing
it over a tree branch does the trick, but usually deployment requires a more powerful
launch such as a a bow and arrow or even a model rocket. Many years ago R/C
Modeler magazine reported on a large radio controlled airplane (Senior Telemaster)
that towed a lead line across a wide gulch …
 Skyworks Solutions, an innovator of high performance
analog semiconductors connecting people, places and things, today unveiled its newest
family of mini circulators for
5G infrastructure. Circulators, which play a critical role in protecting RF
elements from excessive signal reflection, help eliminate performance risks and
safeguard vital equipment. Given footprint constraints in 5G, solution size is also
a key factor. Leveraging proprietary materials and processes, Skyworks' ultra-small
circulators occupy up to 50 percent less board space than competitive products without
compromising functionality - making them ideal for 5G massive MIMO and small cell
applications. Skyworks' mini circulator family represents just one segment of the
company's expansive 5G …
 "This new
memristor mimics the activity of neural networks, but can be
thrown into water and dissolved if data is at risk of falling into the wrong hands.
Neurons are remarkable. Simply by firing in certain patterns and at particular frequencies
in concert with one another, they endow us with something incredibly valuable: memory.
It's no wonder that scientists have long sought to mimic neural networks, which
are both compact and efficient, with electronic devices. One way is with the development
of memristors, devices that retain a 'memory' of the direction and amount of electrical
charge …"
 Rohde & Schwarz develops, produces and
markets
test & measurement, information and communications
technology. Focus is on test and measurement, broadcast and media, cybersecurity,
secure communications, monitoring and network testing. Markets serviced are wireless,
the automotive industry, aerospace and defense, industrial electronics, research
and education, broadcast and media network operations, consumer electronics, cybersecurity
for business and governments, communications and security solutions for critical
infrastructures and the armed forces, reconnaissance equipment for homeland and
external security, and much more …
 According to the Oxford English dictionary,
the definition of an anagram is: a word or phrase made by using the letters of another
word or phrase in a different order; e.g. "Neat" is an anagram of "a net." Therefore,
the title of this puzzle appears to be misnamed. Sometimes an anagram crossword
puzzle is created in which the clues are in the form of anagrams, but even that
is not the case here. With any due apologies to author Comstock, I hereby re-title
this a "High-Fidelity
Crossword Puzzle." The "high-fidelity" part is entirely appropriate since it
refers to the musical nature of the clues and words. As mentioned previously, the
late 1950s through the early 1980s was a major era for interest in high fidelity
radio receivers and playback gear. It represented the transition from powerful vacuum
tube amplifiers to hybrid amplifiers, clear through to high power transistorized
amplifiers. "Man caves" of the day were outfitted with the latest …
 MFJ Enterprises, probably the largest manufacturer
of Ham radio equipment, is for a limited time offering a free downloadable copy
of their e−book entitled, "73 Dipole and Long Wire Antennas." While on the MFJ website,
you might want to take a look at the vast variety of products offered, including
VSWR meters, high power attenuators and terminations, frequency counters, field
strength meters, filters, amplifiers, EMI/RFI suppressors, antennas, antenna analyzers,
coaxial switches, tuners, panel meters, and much more. While some stuff is specific
to Ham bands, most can be used across very wide bandwidths …
 Altum RF, a supplier of high-performance millimeter-wave
to digital semiconductor solutions for next generation markets and applications,
announces
Greg Baker as its Chief Executive Officer. As founder and CEO, Mr. Baker brings
more than 25 years' experience to Altum RF in the RF and microwave semiconductor
industry, including component design, business development, marketing and sales.
With his extensive experience, Mr. Baker provides a clear understanding of product
development, operations and supply chain management, customer partnerships, sales
channels and strategic marketing. Most recently with MACOM as Senior Vice President
and General Manager, RF & Microwave BU, Mr. Baker also previously served as
CEO …
 At VidaRF, the phrase 'Providing Simple
Solutions for Complex Connections' is more than just a slogan – it's a mindset,
a mission, and a driving force behind everything we do. Their pledge is to design
and distribute high performance, cost effective
RF Microwave
products to fit each customer's unique applications. Please visit VidaRF today
to see how their lines of Attenuators & Terminations, Directional Couplers,
Power Dividers, Coaxial Connectors, and Circulator & Isolators can be of use
to your project. "When the standard just will not do, VidaRF has the solution for
you!" …
 I learned something from this poem…
or maybe I re-learned one of the many things taught to me that have been forgotten
- the definition of a vinculum. I admit to having to look up the word in the dictionary
after seeing it. How about you? Do you know what a vinculum is? A vinculum is a
horizontal line placed over a number or numbers to indicating repeating groups (7/11=0.63), or for negation in Boolean equations
(d=a-b+c), and it is also the dividing
line between the numerator and the denominator; e.g. (½) …
 "Engineers at Tufts University have 3D printed
metamaterials with unique
microwave and optical properties that go beyond,
what can be achieved by only using conventional optical or electronic materials.
The fabrication methods developed by the researchers demonstrate the potential of
3D printing to expand the range of geometric designs and material composites that
lead to devices with novel optical properties. In one case, the researchers drew
inspiration from the compound eye of a moth to create a hemispherical device that
can absorb electromagnetic signals …"
 Copper Mountain Technologies
develops innovative and robust RF test and measurement solutions for engineers all
over the world. Copper Mountain's extensive line of unique form factor
Vector Network Analyzers
include an RF measurement module and a software application which runs on any Windows
PC, laptop or tablet, connecting to the measurement hardware via USB interface.
The result is a lower cost, faster, more effective test process that fits into the
modern workspace in lab, production, field and secure testing environments …
 Parenthetically mentioned in this introductory
article on lasers is a "Mie" type particle. At first I thought maybe it was a typo,
but in fact it refers to
Mie scattering, which is the dispersion of electromagnetic waves by isolated
spheres, stratified spheres, infinite cylinders, or other geometries where radial
and angular dependence are independent. Two simple experiments are described for
demonstrating light scattering and absorption similar to what occurs in the atmosphere.
Whereas procuring the 2.5 mW laser source and to a lesser extent suitable light
meter would have been difficult and expensive in 1971 when this was published in
Radio-Electronics magazine, today's cheap equipment puts them within the
budgets of almost anyone. Many of the <$10 cat toy lasers provide plenty of power …
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