Today in Science History -
Lou Frenzel has posted a good article titled, "Electronics Still Thrives as a Hobby" on the Electronic Design
website. While attending his local Maker Faire in Austin, Texas, he discovered some statistics
on the cross-section of electronic hobbyists as gathered by the Jameco Electronics
supply company, who sponsored the event. He expressed surprise at the average age of
participants, but it actually comports well with that of many - if not most - hands-on
(not including game controller and smartphone button pushing) types of hobbies these
If you look just beneath the RF Cafe page title,
you will see the Morse code dits and
dahs that represent this website's name. Click on it and you will be taken to the Morse
Code information page, and therein is an audio player that will sound out the code for
you. The music file was originally created in MIDI format in order to keep it as small
as possible. At the time, all the web browsers supported MIDI files. Times have changed
and now most browsers will not support them. I finally got around to converting the file
to MP3 format, so now the embedded player will provide the intended code transmission ...
"It may be too early for the wireless industry
to make major investments in
spectrum above 95 GHz, but it is the right time for researchers to
take a closer look at the spectrum and see where it might lead. ComSenTer is a newly
formed hub for advanced wireless and sensing research founded by a consortium of industrial
partners and the U.S. Defense Advanced Research Projects Agency (DARPA). ComSenTer researchers
are developing technologies for the high gigahertz and terahertz spectrum that present
opportunities for imaging and sensing capabilities at transmission speeds that are largely
Do you own one of those RFID-blocking wallets
to keep your credit cards from being read unawares? If so, you are engaging in electronic
countermeasures. Anyone interested in the history of
electronic countermeasures (ECM) and electronic counter-countermeasures (ECCM) will
benefit from this 1959 Electronics World article. ECM has been practiced as
early as World War I when wireless communications was first used for military purposes.
ECCM, of course, followed immediately on its heels. Electronic countermeasures range
from simple jamming of receivers to emitting spoofing signals that fool receivers. In
extreme cases ECM can destroy receiver front-ends by overdriving and burning out circuitry.
ECM and ECCM ...
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"Researchers based in Germany claim the first
GaN nanowire MOSFETs with an inverted channel, allowing a positive
2.5 V threshold voltage and giving enhancement-mode normally-off behavior. The high
threshold was achieved by using p-GaN as the channel material. With 0 V on the gate,
the channel blocks current flow. Increasing the gate potential inverts the channel, increasing
the electron density and allowing transport. The team from Technische Universität Braunschweig,
Universität Kassel and Physikalisch-Technische Bundesanstalt sees advantages from GaN ..."
At least 10 clues with an asterisk (*)
in this technology-themed crossword puzzle are pulled from this past week's "Tech Industry
Headlines" column on the RF Cafe homepage. For the sake of all the avid cruciverbalists
amongst us, each week I create a new technology-themed crossword puzzle using only words
from my custom-created related to engineering, science, mathematics, chemistry, physics,
astronomy, etc. 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 ...
Bandwidth Efficiency Techniques Learned
from Cave-Dwelling Fish
"A new light-based device, demonstrated recently
by researchers, could mimic a fish's incredible
Jamming Avoidance Response (JAR) ability. JAR is a behavior performed
by some species of fish when their discharge frequencies are very similar, each fish
will shift its discharge frequency to increase the difference between the two fish's
discharge frequencies. By doing this, both fish prevent jamming of their sense of electroreception.
Moving the frequency of an emitted signal away from other signals that could potentially
cause interference can eventually help overcome the spectral bandwidth ..."
Robert Balin created this
Electronic Factor Quiz for the November 1966 edition of Popular Electronics
magazine. Your challenge is to match the drawing of a particular electronics circuit
or implement with the corresponding "factor." Examples are "current amplification factor,"
"damping factor," "modulation factor," "duty factor," "form factor," "quality factor,"
etc. There are ten in all. Of course on a quiz like this you cannot get just one answer
wrong - or any odd number for that matter. I managed to reverse #5 and #10 (I and B,
respectively). For some reason I couldn't remember what "form factor" was, but was sure
that #10 was a scale factor of sorts... wrong - a clear case of cranial rectumitis ...
Nigel Chapman and Fiona Wilson, of the UK's
AceAxis, have authored a short paper
titled, "PIM in Mobile Broadband Networks - Measurement and Management." "Passive
Intermodulation (PIM) is an unpleasant side effect of the successful deployments of mobile
networks, and is a problem that is growing in impact as complexity increases with the
deployment of 4G and - in the very near future - 5G networks. PIM has the potential to
degrade the efficiency of a cell site, and this network degradation directly impacts
the edge of cell performance and/or the throughput of the cell site. What is PIM? PIM
is a form of intermodulation distortion that occurs in components that are normally thought
of as linear ..."
"Some useful frequencies are elusive or simply
unknown to many engineers, so it wouldn't hurt to take some time and dig through the
FCC 'bible' of federal regulations. If your application is relatively simple, you have
even more choices than you know. Studying the FCC rules and regulations 'bible,' the
Code of Federal Regulations (CFR) 47 Parts 15, 18, 95 and others you can discover some
interesting possibilities. Of late, I learned of one alternative that fits basic industrial
needs and eliminates the complexity of complying with some of the more well-known standards.
This may be of interest if you're designing wireless applications ..."
"Researchers from AMOLF and the University of
Texas have demonstrated a micrometer-sized optical circulator consisting of a silica
microtoroid to which tapered optical fibers feed incoming light beams.
In a paper titled 'Optical circulation in a multimode optomechanical resonator' published
in Nature Communications, the researchers highlight that for the first time, an optical
circulator was designed 'magnet-free,' relying on tiny mechanical vibrations imparted
to a glass ring to directionally route light on an optical chip. 'Light propagation is
symmetric in nature, which means if light can propagate from A to B, the reverse path
is equally possible ..."
This handful of
Ham-related comics appeared in the November 1965 issue of Popular Electronics. One
of them has an operator using "oboe" as the phonetic alphabet version of the letter "O."
Having never seen that before, I did a search and learned that the British Forces in
World War II uniquely used "oboe" for the letter "O." Maybe the artist, Walt Miller,
was either a member of the British Forces or hung around (or served in the military)
with someone that was. For that matter, using "able" for the letter "A" is also a British
thing. The Silent English phonetic alphabet is interesting. I guarantee you'll appreciate
the others as well, or double your money back ...
Centric RF is a company offering from stock various
RF and Microwave coaxial
components, including attenuators, adapters, cable assemblies, terminations, power
dividers, and more. We believe in offering high performance parts from stock at a reasonable
cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500 watts. Order today,
ship today! Centric RF is currently looking for vendors to partner with them. Please
visit Centric RF today ...
Michael Hopkins, founder of CurrentRF, published
an article in High Frequency Electronics magazine titled, "Sensitivity and PSRR Enhancement of RF Amplifiers." Michael developed
the RFDAC methodology and Current Reuse Mixer, and more recently, the PowerOptimizer
and Silicon Supercapacitor methodologies and technologies. "Utilizing the Silicon Super
Capacitor IP demonstrates a substantial improvement in analog and RF circuit sensitivity
and signal cleanliness due to the additional effective capacitance the device and IP
cell provide. With the increased effective capacitance per unit area ..."
Maybe it's just because black and white photos
don't offer the visual stimulus of vivid color that we're used to seeing nowadays, but
these images used to evoke a sense of awe and wonder at displays featured at the
1964 New York World's Fair don't quite hit the mark. Disney played a large role in
the building of the displays. Audiovisual and robotic technology were the main themes
of the event, and no doubt they were impressive at the time, although the recently posted
video of Boston Dynamics' "Atlas" robot / humanoid running through a field puts General
Electric's Progressland's "Grandpa" to shame. Each will give you a different kind of
nightmare. Note Elon Musk's comment on "Atlas." Melanie and I went to Disney World /
Epcot Center on our honeymoon in May of 1983, and saw what was billed as first walking,
talking humanoids where Mark Twain ...
"Nanotechnologists at Oregon State University's
College of engineering have developed a way of fabricating
transistors onto sharply curved surfaces, building on research to develop glucose
sensors that can be wrapped around a tube. Although the research was originally directed
towards diabetes treatments, and these may be an important application for the technique,
it has potential for many other medical applications. The original research was intended
to manufacture a catheter that could be inserted into the bloodstream of a diabetic patient
to continuously measure glucose ..."
Jiri Polivka has an article in Microwaves &
RF magazine that has a different type of topic - using
noise to measure various properties of materials. Any time you can
exploit an entity what would otherwise be considered wasteful and/or a nuisance it is
a good thing. Says Jiri, "Noise can hide details, but it can also reveal them. If properly
used, noise will tell a great deal about a device under test (DUT), including when a
DUT is raw material. For example, the Microwave Noise Field (MNF) test method has the
capability to test different objects that can move ..."
"Since first being awarded in 1901, most
Prizes for science have gone to the U.S., the UK, Germany and France. An empirical
study by Professor Claudius Gros from the Institute for Theoretical Physics at the Goethe
University in Frankfurt has now shown that the Nobel Prize productivity in these countries
is primarily determined by two factors: a long-term success rate, and periods during
which each country has been able to win an especially large number of Nobel Prizes. For
the study, Nobel Prizes for physics, chemistry and medicine were assigned proportionately,
since up to three scientists can share ..."
If you like word puzzles, then maybe you'll want
to give this
word search with names of common electronics components hidden within a matrix of
random letter a go. It appeared in a 1965 issue of Popular Electronics magazine.
Keep that in mind while searching for the Mystery Word. Enjoy ...
Electro-Photonics LLC is a global supplier of
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Our products include SMT hybrid and directional couplers, wire bondable passive components,
filters, and very useful test boards for evaluating components (spiral inductors, single-layer
capacitors). The Electro-Photonics team can support your small R&D design requirements
with RF & Microwave test fixtures and save you valuable design and characterization
time. Please take a moment to visit their website and see how your project might benefit
"Cloaking devices play a pivotal role in many sci-fi television programs.
Scientists are now working to take this technology from the dramatic realm of science
fiction and make it real. Amanda D. Hanford, at Pennsylvania State University, is taking
the introductory steps to make acoustic ground cloaks. These materials redirect approaching
waves around an object without scattering the wave energy, concealing the object from
the sound waves. Hanford will describe the physics behind an underwater acoustic shield
designed in her lab. Hanford and her team set out to engineer ..."