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3 of the May 2018 homepage archives.
Thursday 31
 Usually an article about
clean layout techniques would be about printed circuit board layout; however, this
one refers to chassis layout. Having built many electronics chassis in my days as an
electronics technician (prior to earning an engineering degree), I have a great appreciation
for a professional-looking job. Some of the work done by hobbyists that appear in magazines
like QST, Nuts & Volts, and the older titles like
Poplar Electronics looks pretty darn nice - both for kits and homebrews.
It's a short article, but worth a quick look...
 "Using additive manufacturing, researchers devised
a way to remotely sense motion via
Wi-Fi backscatter,
without any interconnecting wires or need for power at the sensor. IoT and other
sensor-based applications have a constraint: how to connect the switches and
other motion-based sensors to a local Wi-Fi network. Running even a small
switch-closure wire between a transducer source point and a local wireless node
is often a physical nuisance, especially if that point is on a moving object
such as a door or a bottle. To address this problem...
 Looking forward is essential for the advancement
of technology, but looking backward to see from whence we came is beneficial as well.
That is why I post so many articles from vintage tech magazines. Not only does familiarizing
yourself [hopefully] help prevent making the same mistakes over again, but it give you
an appreciation for the sacrifices and innovations that paved the way to the current
state of the art. The same argument can be made for social sciences and politics. Unlike
social scientists and politicians, technologists do actually learn from the past. What
caught my attention in this "Zero-Beating
the News" feature in a 1966 issue of Popular Electronics was the
photo of IBM engineers integrating and testing the electronics equipment...
 DGS, SNG, DNG, CRLH, SRR, and CSRR are amongst
the abbreviations you need to be aware of these days when considering the design of compact,
high selectivity filters for wireless applications. Ahmed Ibrahim, Mahmoud Abdalla, and
Adel Abdel-Rahman wrote a paper titled, "Wireless Bandpass Filters Build on Metamaterials"
that gives an introductions to these and related terms. Metamaterials have the
unique property of a negative dielectric coefficient (and correspondingly
negative refraction) that allows for a whole new set of opportunities for poles
and zeroes...
 "The 2018 interns are about to descend upon Google,
Facebook, Apple, Adobe, and other Silicon Valley companies. Colleges around the country
are winding down their academic years, and in just a few weeks, hordes of tech interns
will descend upon Silicon Valley. They're already combing Airbnb and Craigslist
for housing, trying to align apartment locations with corporate shuttle
schedules, and to decide if they need kitchen privileges or if it's really true
that they'll eat of all their meals at work - for free. Right now, job site
Indeed reports that intern listings are healthy. According to Indeed, the
companies with the most STEM internships..."
Wednesday 30
 Electrical Engineering: A Pocket Reference,
6th Edition, is a "well-organized resource for accessing the basic electrical
engineering knowledge professionals and students need for their work." More than
500 diagrams and figures, 60 tables, and an extensive index. "The book is
organized to help engineers find the information they need in an instant, from
DC and AC systems, electric and magnetic fields, networks, to signals and
systems, digital and analog electronics, and power supplies." Take a look at the
table of contents preview pages to see how extensive it is. Available in soft
cover and Kindle formats...
 David Danzillio, of WIN Semiconductors, published
an article in Microwave Journal magazine titled, "Advanced GaAs Integration for Single Chip mm-Wave Front-Ends." Active
beam-forming antenna arrays are emerging as the configuration of choice for multiple
reasons, including a need for gain in user's direction due to high path losses at millimeter-wave
frequencies. Last week there was a new blurb about Analog Devices' new
beamforming chip
targeting the same type application. 5G is arriving at a snail's pace, largely
because the technology it requires has not been invented yet...
 It should come as no surprise that in the
pre-safety-ground era which included the 1960s that electrical shocks of patients
in hospitals was not uncommon. If the jolt came intentionally from a cardiac defibrillator,
then it would be a good thing. However, these shocks, which were the subject of a
Time magazine story in the April 18th, 1969 issue cited by Mac's technician, Barney,
were being administered unintentionally by patient monitoring and ancillary life-sustaining
equipment. Per the article, no Underwriter's Laboratory (UL) certification was required
for hospital equipment. Maybe it was felt that it wouldn't be so bad if someone got zapped
in the hospital since there would be a doctor on-hand to resuscitate the zapee. Since
that time medical equipment has been required to undergo stringent safety conformance
requirements that makes electrocution virtually impossible. Now, if we could just keep
doctors from cutting off the wrong limb or removing the wrong organ...
 After a successful first edition for the
Industry Days – Additive Manufacturing for RF/Microwave Hardware [2016], we have
initiated the preparation of a second edition. Our main purpose is to trigger the discussion
regarding the manufacturing of RF/Microwave parts using additive manufacturing. We are
sure that, considering the multi-disciplinary environment we will have, the discussion
will be very fruitful. The format for the Industry Days is the same than previous edition.
We will have presentations distributed in two days. To build the agenda, we will open
a period for a call for abstract where any potential presenter can summarise the
scope of the talk and the benefit...
 "In the popular movie franchise "Back to the Future",
an eccentric scientist creates a time machine that runs on a
flux capacitor. Now a group of actual physicists from Australia and
Switzerland have proposed a device which uses the quantum tunneling of magnetic flux
around a capacitor, breaking time-reversal symmetry. The research, published this week
in Physical Review Letters, proposes a new generation of electronic circulators, which
are devices that control the direction in which microwave signals move. It represents
a collaboration between two Australian Research Council Centres of Excellence:
the Centre for Engineered Quantum Systems..."
Tuesday 29
 Television (TV) and high fidelity stereo (HiFi)
were a big deal from the 1950s through the 1970s as
electronics technology underwent major improvements in component capabilities and
research produced high-complexity circuits that featured sophisticated methods of signal
processing. The industry went through the transition from vacuum tubes to transistors
during that three decade period, setting the groundwork for the next generation of microprocessor-based
audio-visual entertainment. Printed comics and TV and radio shows favorite themes included
jokes having to do with Joe Sixpack and his family's anecdotes involving television and
HiFi stereo. Here are a few more from the mid-1960s...
 Sure, this is basically an infomercial for NI
AWR's
AntSyn™ antenna design and synthesis software, but it serves as a
useful introduction to designing and simulating antennas for specific applications. Dr. Derek
Linden, of AWR, demonstrates how to use AntSyn to design and build a customized high-definition
TV (HDTV) antenna by generating a set of antenna specifications such as frequencies,
bandwidth, and gain, for planar antennas such as Yagi and ultra-wideband dipoles.
The article appears in the May 2018 issue of High Frequency Electronics
magazine. The prototype he made for the printed antenna is impressive and
cheap...
 DEV Systemtechnik is the manufacturer of a complete
range of next generation high performance products and systems for the
optical and electrical transmission
of RF signals in HFC cable networks. DEV Systemtechnik has been added to the following
Vendor pages: RF
Amplifiers, RF Power Combiners, Couplers, Splitters & Dividers, RF Switches,
Relays & Matrices, Fuses, Circuit Breakers, and Lightning & Surge Protectors.
Their customers include top tier media companies like Huawei, FOX, Cisco,
Harmonic and Liberty / Unity Media...
 Explaining the working of the
Trinitron color cathode ray tube (CRT) with black and white pictures is a little
like explaining a fourth dimension within the confines of three dimensions. How do you
visualize red, green , and blue in shades of gray? It's like being told to grasp the
concept of tesseract being the 3-D projection of a 4-D cube. Still, that was the
challenge author Forest Belt had when writing this article for a 1972 issue of Popular
Electronics, an era where multicolor print was the realm of high-end
glossy-page magazines. Those of us who were around in the days when Sony's
Trinitron hit the market remember well the hype that surrounded it. Of course my
parent's B&W television suffered the same handicap as this printed page when the
commercials...
May 2018: A Pair of Radar-Related Articles
Power Supply Management of GaN MMIC Power Amplifiers for Pulsed Radar,
by David Bennett and Richard DiAngelo. "Systems that incorporate highly
integrated and highly sophisticated, high power RF GaN PAs, such as pulsed radar
applications, are a constant challenge for today's digital control and
management systems..."
 Fast Numerical Analysis of Scattering and Radar Cross
Section, by Jiyoun Munn. "To demonstrate the effectiveness of 2D
axisymmetric modeling, the author presents a radar-cross-section (RCS) analysis
that utilizes this modeling technique..."
 "While we embrace the way the Internet of Things
already is making our lives more streamlined and convenient, the cybersecurity risk posed
by millions of wirelessly connected gadgets, devices and appliances remains a huge
concern. Even single, targeted attacks can result in major damage; when cybercriminals
control and manipulate several nodes in a network, the potential for destruction increases.
UC Santa Barbara electrical and computer engineering professor Dmitri Strukov is
working to address the latter. He and his team are looking to put an extra layer
of security..."
Monday 28
 J-pole antennas (aka "J" antennas) are so
named due to their physical shape. The basic "J" antenna is a half-wave
vertically polarized antenna that has an integrated parallel feed quarter-wave
tuning stub. It is very popular with amateur radio operators and is still used
with some commercial radio installations. The azimuth radiation pattern and gain
are very similar to the half-wave dipole antenna, as shown in the Wikipedia plot
below. The J-pole was invented in 1909 for use on the German Zeppelin airships
as a trailing wire antenna. Variations of the J-pole have evolved over the years
that in some cases significantly change the radiation pattern, but the
characteristic quarter-wave stub match is retained in all of them...
Download Pentek's Software Defined Radio
Handbook
 Pentek co-founder and VP Rodger Hosking has written
a reference titled, "Software
Defined Radio Handbook," which is a free download from their website.
"Software Defined Radio has revolutionized electronic systems for a variety of
applications that include communications, data acquisition and signal
processing. Recently updated, this handbook shows how DDCs (Digital
Downconverters), the fundamental building block of software radio, can replace
legacy analog receiver designs while offering significant performance, density,
and cost benefits..."
 The Motley Fool sez: "5G is the next step in the
evolution of mobile wireless technology, promising faster speeds, better coverage, and
lower network energy consumption. With most smartphones currently running on 3G or 4G
networks, 5G deployment is still at least a couple of years away. Tech companies are
starting to prepare for what will be the key to powering fast data speeds required by
the Internet of Things (IoT) and self-driving cars.
Skyworks Solutions
provides radio frequency chips to enable wireless connectivity in smartphones
and other devices. It could have a key role in the 5G era through its
connectivity modules..."
Sunday 27
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's (5/21 -
5/25) "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 to this puzzle's theme, such as Hedy Lamar...
Friday 25
 It's Friday and therefore time for a
pop quiz (does that line give you a fearsome flashback to your school
days?). Whenever I have one available, I like to post quizzes from vintage
electronics magazines, like this one on diode circuit functions. Many of them
have vacuum tubes, but this one has the solid state symbols so the under-40
folks won't be uncomfortable. Your job is to look at the diode circuits and
match them with the names of the functions. A couple of them will probably cause
some head scratching, but you should do well. Don't jump to a quick conclusion
with circuit "E" without noticing the two signal generators attached to it...
 "Graphene Flagship researchers have shown for
the first time gate tunable third harmonic generation in graphene. This research, led
by Graphene Flagship Partner University of Cambridge, in Collaboration with Politecnico
di Milano and IIT-Istituto Italiano di Tecnologia in Genova and published in Nature Nanotechnology,
could enable on-chip broadband optical switches for data transport in optical systems.
Optical harmonic generation is the creation of new frequencies (colours) when
high intensity light interacts with a nonlinear material. Third Harmonic
Generation (THG) can create light..."
 Istvan Novak has a clever low budget, close-enough
type fixture for quickly measuring the impedance (and determine the self-resonant frequency)
of capacitors up through a few tens of MHz. Mr. Novak's application is bypass
capacitor characterization. "Bypass capacitors are used in large
numbers in power  distribution
networks. Most vendors today supply not only typical characteristics, but also
various simulation models. Nevertheless, doing our own characterization of these
components is still useful and often necessary. In this short article, I'll show
you how to create simple home-made fixtures for these measurements. For bypass
capacitors, measuring impedance over a reasonably wide frequency range..."
 Restoring and/or upgrading vintage radio receivers
is still a very popular pastime for hobbyists, and for that matter for some professional
servicemen who preform maintenance on established equipment installations. Three of the
most significant changes that can be made to older receivers to
improve sensitivity are to clean up the power supply DC output, replace
noisy components like vacuum tubes and leaky capacitors, and tune / modify /
replace RF and IF filters. This article discusses a method of replacing a stock
LC filter with a high selectivity mechanical filter. The nice thing about an
analog receiver is that narrowband, steep-skirt filters can be substituted
without concern for group delay at the band edges that can (and will) wreak
havoc on digital signals...
 Saelig Company has introduced the
Circuit Design SLR-434M Smart Modem - a compact, easy to use narrow-band embedded
radio modem operating in the 434 MHz ISM band. It incorporates LoRa® technology
to achieve extremely long range for low bit-rate data with low power. The
SLR-434M's excellent receiving sensitivity allows communication into areas once
considered difficult for RF to penetrate, and making it possible to transmit
1800 feet or more. The SLR-434M is also switchable to accommodate...
 "A new discovery may dramatically improve heat
transport in insulators and enable new strategies for heat management in future electronics
devices. The discovery was made by researchers at the Department of Energy's Oak Ridge
National Laboratory who made the first observations of waves of atomic rearrangements,
known as phasons, propagating supersonically through a vibrating crystal
lattice. The discovery gives a different way to control the flow of heat. It
provides a shortcut through the material..."
Thursday 24
 "A new
beamforming chip
promises to shrink the size and weight of aircraft antennas by eliminating the
need for mechanical steering linkages. The chip could serve in radar for defense
aircraft and for in-flight broadband on commercial jets. Analog Devices, maker
of the new chip, also foresees it being used in air traffic control,
surveillance, weather monitoring, and even 5G communications. ADI engineers say
the key is the product's inherent ability to cut size and weight. “By going to
an electronically steered antenna design, we are able to reduce the size of the
antenna element itself and eliminate the mechanical arm and motor..."
 RF component manufacturer
Pasternack Enterprises has
a useful article in the May issue of Microwave Journal titled, "5G Update: Standards Emerge, Accelerating 5G Deployment." I am still
a bit fuzzy on what exactly 5G entails, other than it must be better than 4G since it's
a whole number higher. This helps a little. "Though the expected features and use cases
for 5G are diverse and extensive, the start of the 5G rollout will likely address only
a few of the featured use cases: enhanced mobile broadband (eMBB), ultra-reliable low
latency communications (URLLC) and massive Internet of Things (mIoT) or massive machine-type
communications (mMTC)..."
 Sugar Grove, West Virginia, is within the U.S.
National Radio Quiet Zone (NRQZ), which also encompasses the Green Bank, WV
area. It was established by the Federal Communications Commission (FCC) in 1958
to protect hypersensitive, cryogenically cooled radio astronomy receivers from
manmade terrestrial signal sources. As you can imagine, there are not many
places remaining in human-inhabited regions of earth that are not massively
invaded by radio frequency energy. If you visit the area today, you had better
not have your cellphone, computer, or other RF-producing device turned on or you
can be subject to a hefty fine. Roving signal detecting trucks monitor the
region for offenders. This 1961 report on advances in electronics also features
the world's first computerized bank check...
 Gowanda Components Group is pleased to announce that its offerings
of RF and microwave passive magnetic components are expanding in connection with the
acquisition of HiSonic in Olathe, Kansas. "HiSonic's designs, technologies and customers
complement those within our Magnetics Division," said GCG CEO Don McElheny. "The
synergy in our capabilities and applications will enable us to offer a broader
range of innovative inductor and transformer solutions to design engineers in
commercial, medical, microwave, military, space and other markets around the
world..."
 "Only a few decades ago, finding a
particular channel on the radio or television meant dialing a knob by hand,
making small tweaks and adjustments to hone in on the right signal. Of course,
we now take such fine tuning for granted, simply pressing a button to achieve
the same effect. This convenience is enabled by radio frequency synthesis, the
generation of accurate signal frequencies from a single reference oscillator.
The need for better radar in World War II drove the development of radio
frequency control, and its miniaturization in subsequent decades revolutionized
a host..."
Wednesday 23
 With a fair helping of chagrin, I admit to being
a "10-4 Good Buddy" type of Ham radio operator. That moniker is applied liberally by
pre-1991 (February 14, to be exact) amateur radio licensees to post-1991 licensees because
that was the year in which the FCC no longer required aspiring Hams to pass a
Morse code proficiency test for an entry level license. It was a sort of
Valentine's Day gift. In 2003, the ITU announced the rescinding of its code
requirement and allowed countries to set their own standards. By 2007, General
and Amateur Extra exams no longer required code tests. I earned my Technician
license in 2010...
 Written by Terry Edwards, "Technologies for RF Systems"
is a comprehensive resource provides an introduction to the main concepts,
technologies, and components in microwave and RF engineering. This book presents
details about how to design various amplifiers, circuits, and chips for
communication systems. It offers insight into selecting appropriate ADC and DAC
technology. Several worked examples are found throughout the book. This book
provides a summary of 21st century RF systems and electronics and discusses the
challenges of frequency bands and wavelengths, software-defined radio (SDR) and
cognitive radio. RF semiconductors are covered, including band gap, drift
velocity...
 "A new
magnetic lattice material developed by researchers at the University
of Missouri could be used to increase the battery life of electronic devices by more
than a hundred times, it is claimed. Singh's team developed a two-dimensional, nanostructured
material created by depositing a magnetic alloy, or permalloy, on the honeycomb
structured template of a silicon surface. The new material conducts
unidirectional current, or currents that only flow one way. The material also
has significantly less dissipative power compared to a semiconducting diode,
which is normally included in electronic devices..."
 A lot of nostalgia gets waxed here on RF Cafe,
to which frequent visitors can readily attest. Old timers (if you're not one now, you
some day will be) often like to see remembrances of days of yore, the halcyon days of
past hobbies, family, long naps, school (yuk), vacations, and other pleasurable times.
Hopefully, you already have or will soon have a few of your own. This 3-page
Lafayette Radio Electronics spread from a 1965 issue of Popular Electronics
magazine is typical of what what avid electronics hobbyists would have read and
drooled over with so many great items in the offering. If you were like me, the
cost of most of the things I wanted were well outside my budgetary reach. Prices
for electronics gizmos were quite high...
 everything RF has created the largest database
of searchable RFID products.
We have compiled complete catalogs from the leading RFID manufacturers across 6
categories and make the products searchable by specification: RFID antennas,
RFID reader ICs, RFID reader modules, RFID readers, RFID tag ICs, and RFID tags.
everythingRF has also created parametric search tools in each category and are
now adding more products and companies to the system...
 "There are still some places the Internet of Things
fears to tread. Researchers at the University of Arkansas and the KTH Royal Institute
of Technology, in Sweden, are building a radio for those places. This month, in IEEE
Electron Device Letters, they describe a mixer, a key component of any wireless
system, that works just fine from room temperature all the way up to
500 ºC.
It's the first mixer IC capable of handling such extremes. Of several projects
'one of the more sexy is trying to put a rover or some sort of instrument on
Venus that will last for more than two hours..."
Tuesday 22
 A news story with a title about a boat and reverse
current is more likely to be referring to water flow in a river or stream than about
electrical current in a conductor. Having grown up in a neighborhood next to a tributary
of the Chesapeake Bay, I spent quite a bit of time around boats, both large and small.
Salt water is particularly destructive to metal hulls due to
cathodic corrosion, exacerbated by the salt water's conductivity. While working as
an electrician in the 1970s, I installed electrical supplies for a few dockside cathodic
protection system that probably functioned like the one described in this 1965 issue
of Popular Electronics magazine. The principle is fairly simple whereby
anodes are placed in the water around the hull and a counter-current is
induced...
 It'll come as no surprise to any savvy buyer,
and certainly not to any design engineer, that each new generation of electronic products
packs more performance into a smaller package than the product it replaced. No matter
whether it's a remote industrial sensor node or the next smart wearable device, space
is becoming an increasingly scarce resource. Aimed at IoT and personal electronics applications,
the TLV9061 consumes only 0.64 mm2 and is the
world's smallest op amp. Something's gotta
give. In this case, many things. Fitting the increased capability into a smaller
volume requires the designer to make improvements in multiple areas. The three
biggest keys to succeeding, however, are to reduce the overall power
consumption...
 Cesium-137, iodine-131, carbon-14, plutonium-239,
strontium-90, uranium-235, and the list goes on. These and other
radioisotopes associated with nuclear material are the result of explosions,
medical treatments, laboratory experiments, or in some cases naturally occurring
deposits. Regardless of the source, most people, including me, cringe at the
thought of being exposed to the insidious effects of the cell-altering energy
they possess. Ionizing radiation is the dangerous type of radiation due to its
ability to dislodge electrons from atoms, and in the process forming cancerous
cell mutations or killing the cells altogether. Researchers in the early days of
radiation discovery experienced sometimes gruesome maladies as a result of the
handling isotopes. Some knowingly subjected themselves to harmful doses...
 Saelig has introduced the
STD-302Z 434 MHz Narrow Band Multi-Channel Transceiver
- a half-duplex UHF radio module that is suitable for industrial remote control
and telemetry applications operating in the 434 MHz ISM band. The STD-302Z is
designed with SAW filter and narrow-band filtering techniques to provide
reliable data communication in industrial situations where interference
rejection and practical distance range operation are required. Offering 10 mW of
RF power from its PLL-synthesized transmitter with programmable RF channels, the
STD-302Z's double superheterodyne receiver sensitivity is specified down to
-119 dBm...
 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...
 "The future of electronic devices lies partly within
the 'internet of things' - the network of devices, vehicles and appliances embedded within
electronics to enable connectivity and data exchange. University of Illinois engineers
are helping realize this future by minimizing the size of one notoriously large element
of integrated circuits used for wireless communication - the transformer. Three-dimensional
rolled-up radio frequency transformers
take 10 to 100 times less space, perform better when the power transfer ratio
increases and have a simpler fabrication process than their 2-D progenitors,
according to a paper detailing their design..."
Monday 21
 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 days...
 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 unheard..."
 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 receiver. In extreme cases ECM can destroy receiver
front-ends by overdriving and burning out circuitry. ECM and ECCM...
 Please express your appreciation to
Rigol Technologies for their support of RF Cafe. Rigol's
extensive line of products includes digital and mixed signal o-scopes, spectrum
analyzers and RF signal generators, arbitrary waveform generators, power
supplies, sensitive measurement products, and data acquisition systems.
Applications include applications such as technical education, embedded design,
WiFi integration, EMC, and manufacturing. Backed with a 3 year warranty and a 30
day no questions asked return policy...
 "Researchers based in Germany claim the first
vertical
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..."
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