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3 of the July 2016 homepage
archives.
 "This is the first useful device that exploits
charge-density wave modulation of current through a 2D material, claims the University
of California Riverside, which worked with the University of Georgia. Graphene can
conducts electrons rapidly, but has no usable bandgap from which to forge switching
behaviour. Instead of switching with graphene, a 2D crystal form material tantalum
sulphide (TaS2) was
..."
 Although single capacitor, single inductor
resonant tank circuits are not widely used, one place you do find them is in transistor
amplifier stages in order to peak gain in a particular frequency band. Author Jack
Najork offers here a few pointers regarding preforming quick mental calculations
for how ranges of capacitance values affect the resonant frequency. For instance
the
ratio of capacitance values needed to cover a certain range of
resonant frequencies is equal (ideally) to the square
root of the frequency ratio. This comes into play both when determining values during
the design phase and the selecting a variable capacitor for providing tuning
...
 Each month I randomly select 1 or 2 people
from my
software purchaser list and offer to award a free book in the
monthly RF Cafe
Book Drawing. Also each month most people never respond to my notice of being
a winner (probably thinking my e-mail notice is spam).
Most of the books sell for >$100 on Amazon. This month, fortunately, Robert E.,
of Carlisle, Massachusetts, did respond. He wisely selected
Highly Integrated Low-Power Radars, by
Sergio Saponara, Maria Greco, Egidio Ragonese (graciously
provided by Artech House).
 In this issue: Wolfspeed, a Cree company
that stands alone as the premier provider of the most field-tested SiC and GaN Power
and RF solutions in the world, is currently sponsoring free access to Dr. Francesco
Fornetti's "Conquer Radio Frequency: a Multimedia Conceptual Guide to RF &
Microwave Engineering using AWR Microwave Office." This resource contains more
than twelve hours of video tutorials supplemented by a reference textbook. The tutorials
cover: Transmission lines, Smith Chart, S-parameters, Impedance matching with both
discrete and distributed elements, Basics of amplifier design
...
Following a four-year development program, Aaronia launched the
Drone Detector, a product that exploits the RF radiation emitted
by the UAV's onboard systems and by the operator's control unit. Two types of 3D
direction-finding antenna are offered by the Drone Detector—the IsoLOG 3D 80-UWB
and IsoLOG 3D 160-UWB. Both cover from 9 kHz to 6 GHz, and extenders are available
should VLF (below 9 kHz) and 6-20 GHz coverage be
required. The Drone Detector has a real-time bandwidth of 80 MHz. Optionally this
can be extended to 175 MHz
 Take a break and work this week's
RF Engineering-themed crossword puzzle. All the words are pulled
from a hand-built list of terms, names, and abbreviations that have only to do with
science, mathematics, and engineering. Clues for words having to do with types of
engineers are marked with an asterisk (*). If you want a crossword with names of
movie stars and obscure countries, try the local newspaper
...
 Electronic warfare (EW) is a familiar term
today, but in 1947 its use was a relatively new concept. As you know, great advancements
in electronics occurred during the War years - from all the major Allied and Axis
countries involved. Transmitters and receivers, modulation techniques, antenna designs,
transmission lines, component introductions and improvements, ruggedness and portability
features, reliability, serviceability, operational techniques, and other aspects
of electronics benefitted from that oft-credited 'mother of invention' named 'necessity.'
Along with electronic communication improvements came the need to thwart the enemy's
...
 Withwave's
Compact Calibration
Kits offers excellent performance characteristics that is specially designed
for the fine-tuning in production environments and quality testing facilities using
50 ohm N-type & 3.5 mm connectors up to 6 GHz and 9 GHz, respectively.
This Cal Kit includes all needed calibration standard (Open, Short, Load) in one
unit that is best solution available for ease of use in VNA calibration, especially
in the field ...
 Thanks once again to the folks at everythingRF
for advertising on RF  Cafe! It is their support that helps deliver this
website to you.
everything RF is a product discovery platform
for RF & Microwave Products/Services. We currently have 211,299 Products from
more  than 1,027 Companies across 222 Categories in
our database and enable engineers to search for them using our customized parametric
search tool.
 Recently, a company based in China contacted
me about advertising on RF Cafe. After doing a lot of up-front work for them creating
advertising materials, the representative informed me that he cannot access the
RFCafe.com domain from his location. It is really difficult to conduct business
when the customer cannot review your work, so at least for now, I am going to pass
on the opportunity. The obvious question that arises from the experience is whether
RFCafe.com is being blocked by China, and how do I find out? Fortunately, a few
options exist with websites that will perform the check for you by pinging your
URL from servers within multiple countries. Some, such as GreatFirewallOfChina.org, tests from inside China using servers
in Beijing
...
 "Europe's largest particle accelerator, the
Large Hadron Collider, is back in action.
According to two newly published studies, its latest round of experiments yielded
three new 'exotic' particles and confirmed the existence of a fourth. The newly
identified particles are considered 'exotic' because they contain four quarks, the
building blocks of all matter. Particle physicists used to believe all particles
were composed of mesons, a quark-antiquark pair, or baryons, three
..."
 Mr. John Higgins, of the
Ace Wire Spring & Form
Company, wrote to ask that his firm be added to the
Hardware Vendors
page on RF Cafe. Located in McKees Rock, PA, Ace is an industry leading precision
manufacturer of compression springs, extension springs, torsion springs, specialty
springs, and wire forms. Free engineering design services available. Please contact
them to see whether you have a need they can fill. 412-458-4830
...
 Whenever
I think of springs, the goofy short film "A Case of Spring Fever" comes to mind. 'Coilie the Spring Sprite'
teaches Gilbert an important life lesson after wishing for 'no more springs!'
Anatech Electronics,
a manufacturer of RF and microwave filters, has published its July 2016 newsletter.
As always, it includes both company news and some tidbits about relevant industry
happenings. This month, Sam Benzacar continues his previous discussion regarding
the increasing challenge that interference is to mission-critical systems. He also
reports on news about cancers risks that come with extensive cellphone use, LTE-U
deployment schedules, E-Band data system advances, and using radar-based sensors
to monitor and characterize patient behavior and health status. Anatech's business
is to make certain that system
 June 1931 was a year and a half into the
Great Depression, which began with the Wall Street crash of October 1929. It followed
on the heels of the very prosperous decade known as the "Roaring Twenties," when
significant, rapid advances in technology had taken place in electronics, medicine,
physics, chemistry, and other fields. A huge number of radios were sold to the military,
businesses, and private consumers both before stock market crash and after. A quick
look at my list of Radio Service Data Sheets from the era show that to be so. In
fact, it wasn't until World War II that production of new radio sets began
to decrease, as all available
...
 "Amateur Electronic Supply (AES) will
close its doors at the end of July after 59 years in business. No reason has been
given for the decision to close the business. AES has been a premier player among
Amateur Radio equipment retailers for decades, as well as a major presence at Dayton
Hamvention® and other events. Various media outlets were informed of the closing
in a brief e-mail message on July 6, but word of the closing has not yet appeared
..."
We have recently updated the
Antenna
Search tool on everything RF. There are 4,000 Antennas from 48 manufacturers
listed on the site. Use the search tools to find antennas by Type (Dipole, Yagi,
Whip, etc.), Frequency, Gain, Industry Type (IoT, Military, SATCOM, etc.), Communications
Standard (WLAN, Bluetooth, GPS, etc.), Frequency Band (UHF, L, S, C, Ka, etc.),
Mounting (Pole, Magnetic, etc.) and a number of other parameters. Please let us
know what you think. We are still adding more products and manufacturers
 The mission of the
Graphene Flagship is to translate graphene out of the academic
laboratory, through industry and into society. This broad and ambitious aim has
been at the forefront of the choices made to direct the Flagship; it focuses on
real problem areas where it can make a real difference such as in Optical Communications.
Optical Communications are increasingly important because they have the potential
to solve one of the biggest problems of our information age: energy consumption.
Almost everything we do in everyday life consumes information and all of this information
is powered by energy
...
 Just as the paperless office, predicted to
quickly become a reality when personal computers were beginning to dominate the
workplace and home in the 1980s, has yet to occur, neither has desktop software
for high-end applications totally replaced online equivalents. Microsoft has made
good progress in the last few years in moving part of their Office suite online,
you still need a local copy of Visio, Project, and even their Visual Studio software
development tools if you want to use them. Graphics and video editing software cannot
be used efficiently online. The problem is mostly due to time latency between user
input and software display response. Speed on the host server end is addressable
with pumped up computing power and extra
...
 "The
Five-hundred-meter Aperture Spherical radio
Telescope (FAST) is a mega-project designed to search the cosmos for clues about
our creation and whether there are any other civilizations out there. The project
began development back in March of 2011. Five and a half years later, it is finally
functional. The telescope, as the name would suggest, is a monstrous 500 meters
in diameter, able to achieve a zenith angle of 40 degrees. The telescope
..."
You just never know when your number is going to be called. People who engage
in a dangerous activity they love often claim that if they are going to die in an
accident, it would preferably be while engaging in that activity. It really sucks
to die like Army-Air Force
Lt. Henry
B Harris who was an accomplished instrument flight research pilot (and
noted Ham radio operator). Rather than expiring in an airplane, he met his end as
a passenger in a car that was towing some other pilot in a glider
...
 "Mimicking nature is not easy, but new insights
by researchers at the Department of Energy's Lawrence Berkeley National Laboratory
could help create a viable artificial system of photosynthesis. One of the major
challenges for scientists working to create systems that efficiently convert sunlight,
water and carbon dioxide into fuel is finding materials that can do the work while
also surviving the corrosive conditions that are part of the process
..."
Skyworks Solutions, an innovator of high performance analog semiconductors connecting
people, places and things, today expanded its best-in-class antenna tuning product
portfolio with the addition of several new high performance solutions. Skyworks'
latest antenna tuning offerings address the design challenges mobile device manufacturers
face as smartphones become thinner, leverage revolutionary case materials and integrate
more cellular bands. By optimizing radiated efficiency, Skyworks' antenna aperture
tuners enable higher data throughput and smaller footprints, minimizing dropped
calls and improving the consumer experience. 'Cellular band proliferation in smartphones
"
 "Conventional USB flash drives are electronic
data storage devices. They store information by using millions of small gates that
process information into 'words' consisting of various combinations of the numbers
0 and 1. A team of scientists at Hokkaido University's Research Institute for Electronic
Science investigated the possibility of using a
magnetic signal along with the electronic
signal to allow double the storage capacity in these 'multiplex writing / reading'
devices. In addition to the binary
..."
 Even if you have no use for building a "twin
lamp" standing wave indicator for a
twin
lead transmission line (solid or open ladder type), this article makes an interesting
read for its theoretical description of how the device works based on current phases
in the circuit. A pair of flashlight bulbs and couple feet of wire is all that is
needed. When operating properly, the "twin lamp" indicator indicates by virtue of
whether one or both bulbs are illuminated whether there is a significant standing
wave present on the line. Author Charles Wright warns that the VSWR level cannot
be reliably determined based on relative brightnesses of the two bulbs; it is meant
for use as a best case
...
 "Rensselaer Polytechnic Institute and General
Electric Global Research Center in the USA 'experimentally demonstrate, for the
first time, bi-directional 4H-silicon carbide planar gate, insulated-gate bipolar
transistors (IGBTs) fabricated on 250μm-thick, lightly doped free-standing substrates.'
The researchers see potential for their bi-directional (BD) IGBTs as switches that
can control current in both directions with application in matrix or neutral point
piloted multi-level converters. Compared with multi-component implementations
..."
 "Just because it's futuristic doesn't mean
it's practical." - Crow T. Robot, MST3K, 'Design for Dreaming,' Mystery Science Theater 3000 (MST3K). MST3K
was a TV series in the 1980s-1990s where a human was forced by evil scentists to
watch B movies, with automatons
 Crow
T. Robot and Mike Servo provided for comfort. Their silhouettes are seen in the
theater's front row as they make wise cracks about and gestures toward the movie
as it plays. One of my favorite clips is from the "Space Mutiny"
film, where Crow, Mike, and Servo roll out a long string of insulting names for
the 'hero' character. You'll definitely get a laugh out of it.
 "Researchers at the Oak Ridge National Laboratory
in the U.S. and Uppsala University in Sweden have developed a new electron-microscopy
technique that can detect
magnetism at the atomic scale. The technique
exploits distortions - or "aberrations" - in how the microscope's electron beam
is focused, and could be used could be used to study magnetic domains in devices
such as computer hard-disk drives. Electron microscopes focus beams of electrons
in much the same way that optical microscopes
..."
 Summer has traditionally not been the best
time to be job hunting in industries where project budgets begin and end
on the calendar year, but I these days there probably are no discernable rules.
A lot of advice has been written regarding what to do and what not to do during
job hunting and during the first months of employment. As with technology, the list
of do's and don'ts regarding all aspects of a career change over time. Workers today
need to know about how to exploit and/or avoid social media, how to handle interviews
within the constraints ...
 "Researchers at Cornell University have fabricated
graphene membranes into micrometer-scale
drums that can be stimulated by a voltage to transfer one type of mechanical vibration
into another. The researchers believe this capability can lead to new applications
in telecommunications where graphene-based mechanical resonators could be used as
frequency mixers, which are often used, for example, to modulate carrier waves with
signals
..."
 This might be my oldest copy of QST, being
Vol. XIII, Number 6 (December 1915 was the first issue).
Up until a few decades ago, authors commonly appropriated themes and characters
from familiar fairy tales and fables for use in articles of instructional nature.
Some publications even used comic book style formats for teaching to beginners.
The term 'wabbulation' (aka 'wobbulation') is spoken
to Uncle Jimmy by the fabled Piper, and I have to admit not being familiar with
the term. According to W2PA's story, 1920s era QST technical editor Robert
Kruse coined the word to describe inadvertent modulation
...
 The following announcement was posted in the
September 1930 edition of
Radio-Craft magazine regarding Radio Data Service Sheets:
"We are pleased to announce that RADIO-CRAFT has taken over the subscription
list of "RADIO SERVICE," formerly published in Dallas, Texas. All subscribers of
record to RADIO SERVICE will receive RADIOCRAFT until the expiration of their subscriptions."
 A few days ago, Mr. Tim O. sent me photos
of the
Crosley model 03CB console (floor) radio that his mother owns
and which he remembers listening to as a kid. Tim says as far as he knows the radio
still works. As can be seen in the images below, it is still in pretty good condition
for a 75-year-old radio! I noticed that both the volume and tuning knobs appear
to be a bit melted, which must have been a common occurrence in this model because
the Crosley 03CB radio that I recently bought and restored also had melted volume
and tuning knobs. The metal chassis
...
 For the sake of avid cruciverbalists amongst
us, each week I create a new
crossword puzzle that has a theme related to engineering, mathematics,
chemistry, physics, and other technical words. This one has extra words pertaining
to radar and radio. You will never be asked the name of a movie star unless he/she
was involved in a technical endeavor (e.g., Hedy Lamar).
Enjoy!
 The free 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.
Note: I earn a few pennies (literally) when you download
one of these or the many other pubs available, so please help yourself.
 "The Wi-Fi Alliance this week announced its
expanded
Wi-Fi Certified ac to include new features
that provide a better experience. The new features in 802.11ac Wave 2 should provide
operators and their end users with big improvements in the user experience. One
of the most talked about features – multi-user multiple input multiple output
(MU-MIMO) - allows more devices to operate simultaneously
on the same network. The ability for a single access
..."
 The VOLSCAN (Volume
Scanning) radar system was a paradigm changer for air traffic controllers
charges with guiding aircraft while assuring safe separation. Busy terminal areas
were a particularly difficult challenge due to the large variation in aircraft speeds
and types.
VOLSCAN was a computer that tracked the position, direction, and
speed of each target and even made recommendations to controllers for course assignments.
It also warned of impending dangerous scenarios. Another VOLSCAN article in the
July 1954 issue of Radio-Electronics went
...
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