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5 of the May 2019 homepage archives. Friday 23
 Exploiting the electronic nature of living
organisms through contrived application and manipulation of electric currents has
been a goal of researchers (and quacks) ever since Luigi Galvani first discovered
that connecting a battery lead to a frog's leg would cause it to kick.
Psychogavanic reflex (PGR) is the technical term for the science. Once it
was determined that all forms of fauna would respond to electrical stimulation,
it wasn't long before the same sort of treatment was applied to all forms of
flora. Many people (not me, for the record*) believe that talking to plants can
influence their health and growth, so why not - so goes the reasoning - try
electric currents as well. We all know from spy, war, sci-fi, and horror movies
that under the right conditions...
 Anatech Electronics (AEI) manufactures and
supplies RF and microwave filters for military and commercial communication
systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters,
and RF products. Standard RF filter and cable assembly products are published in
our website database for ease of procurement. Custom RF filters designs are used
when a standard cannot be found, or the requirements dictate a custom approach.
Sam Benzacar's monthly newsletters address contemporary wireless subjects.
Please visit Anatech today to see how they can help your project succeed...
 This is yet another example of humorous -
and clever - poetry written by Hams from back in the 1940s... November 1942, to
be exact. It appeared in the ARRL magazine QST. As alluded to in the title,
"Ravin," it is a play
on Edgar Allen Poe's famous "The Raven" poem. A few other electronic-themed poems
are listed on the page as well, discovered in QST and in Popular Electronics.
Enjoy...
 Alliance Test sells
used / refurbished
test equipment and offers short- and long-term rentals. They also offer repair,
maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP,
Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization
with ability to source hard to find equipment through our network of suppliers.
Please visit Allied Test Equipment today to see how they can help your project...
 Personal note: Alastair is one of the nicest
guys you'll ever work with. "Anokiwave, an innovative company providing highly integrated
IC solutions for millimeter-wave (mmW) markets and Active Antenna based solutions,
today announced the latest addition to its executive leadership team with the appointment
of
Alastair Upton to the position of Chief Strategy
Officer, a new position within Anokiwave, effective May 2019. Mr. Upton will report
directly to Chief Executive Officer, Robert Donahue. As the Anokiwave CSO, Alastair
will be responsible for developing and executing Anokiwave's business strategy
in all key markets, including responsibility for the strategic marketing
organization, driving the company product roadmaps, and managing partnership
programs..."
 "As far as we know, Earth's
magnetic north
has always wandered, but it has recently gained new momentum and is making a
dash towards Siberia at a pace not seen before. While this has some practical
implications, scientists believe that this sprint is being caused by tussling
magnetic blobs deep below our feet. Unlike our geographic North Pole, which is
in a fixed location, magnetic north wanders. This has been known since it was
first measured in 1831, and subsequently mapped drifting slowly from the
Canadian Arctic towards Siberia. One of the practical consequences of this is
that the World Magnetic Model has to be updated periodically with the pole's
current location. The model is vital for many navigational..."
 Please take a few moments to
visit the
everythingRF
website to see how they can assist you with your project. everythingRF is a
product discovery platform for RF and microwave products and services. They
currently have 227,460 products from more than 1210 companies across 285
categories in their database and enable engineers to search for them using their
customized parametric search tool. Amplifiers, test equipment, power couplers
and dividers, coaxial connectors, waveguide, antennas, filters, mixers, power
supplies, and everything else. Please visit everythingRF today to see how they
can help you...
Thursday 23
 A few months ago, one of America's big-city
mayors made the proclamation, "We're not going to make America great again. It was
never that great." There has been a big push in the last decade to not only erase
the
significant accomplishments and sacrifices of America's and Western Europe's
past, but to vilify those people and institutions that make up that past.
Purging the records and rewriting history is a tried and true method of assuring
few have easy access to archival material documenting the accomplishments of the
nation's past. Along with desiring to provide useful and interesting material to
people seeking technical and historical information, my motivation...
 A supporting company representative requested
that I update the
website traffic
statistics chart with current information since the old one was a year old.
Wow, tempus fugit. April 2019 numbers are now available. RF Cafe typically
receives 8,000-15,000 website visitors each weekday and about half that
on weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and
students all over the world. With more than 8,000 pages in the Google search
index, RF Cafe returns in favorable positions on many types of key searches,
both for text and images. New content is added on a daily basis. Items added on
the homepage are broadcast on LinkedIn...
 This
subscription renewal for Radio-Electronics magazine was tucked
inside one of the group of 1969 issues I bought on eBay. It's not a big deal,
but is always interesting to see how the companies communicated with customers
in the day. Note that the mailing address for Radio-Electronics is simply
Boulder, Colorado, with no street address given - all the mailmen must have
known where they were. The cost was $12 per year...
 Sure, its really an infomercial, but the "Inside Story" piece in the May NASA Tech
Briefs, written by Pico Technology's Mark Ashcroft, provides a good insight
into what drives the cost of modern oscilloscopes. Per Mr. Ashcroft, "Back
in 1928 Messers Nyquist, Shannon, Kotelnikov and Whittaker all concluded that to
sample any continuous analogue waveform into discrete sampled (digital) form we
must have at least two samples within a cycle of the highest frequency that we wish
to represent. In practice we have to go further than that if want to reveal waveshape
detail or make meaningful repeatable measurements..."
 This line from the Basic Navy Training
Courses is very important when considering electrical machines: Many electrical
devices and machines operate on the principle of "transformer
action." They in fact are not transformers - but the theory of their operation
is best explained by considering them as if they were transformers. It is part of
chapter 21, entitled, "Some Electrical Machines - Transformer Action," which provides
a simple introduction to induction motors and generators, regulators, frequency
converters, and synchros. If you are a newcomer to the field of electricity
and/or electronics, or if you just want to brush up on old knowledge to be
conversant at office parties, this is a great short read. A quiz is provided at
the end...
 "The U.S. Air Force has deployed 20 missiles
which can zap enemy electronics with powerful pulses rendering weapons virtually
useless. They can be launched into enemy airspace at low altitude and emit blasts
of high-power microwave energy that immediately disable any devices targeted. The
Counter-Electronics High Power Microwave Advanced
Missile Project (CHAMP) is the brainchild of Boeing's Phantom Works lab. They
have not been operation until now and could be used to frazzle the military defences
of Iran and North Korea, reports DailyMail.com. News of the state-of-the-art
weapons - which are carried into battle by B-2 stealth bomber..."
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...
Wednesday 22
 After many years of reading
Mac's Service Shop sagas, a persistent theme seems to be Barney's refusing
to refer to equipment schematics while troubleshooting, thereby often wasting
valuable time. According to business owner and electronics sage Mac McGregor,
assuming that what is typical for most sets will apply to all sets can and does
create a fertile environment for frustration - and profit loss. Mac's advice to
check "simple things first," has always been my troubleshooting philosophy -
maybe because identifying the "hard things" has nearly been my undoing many
times when the trouble is not simple. One of first things I do is check
switches, connectors, and user-accessible potentiometers for proper operation
(when potentially responsible for the problem, of course). I've written many
times about how often a dirty connector is the culprit...
 If you need to design just about any filter
type ever conceived, then Nuhertz Technologies probably has software that can do it. The
really big dollar microwave design software suites from Keysight and NI/AWR have
synthesis tools, but if you only need to design filters, look no farther. Jeffrey
Kahler has an article in MWJ entitled, "Complete Filter Design with Discrete Elements Made
Easy," that gives some insight into Nuhertz's capabilities, but you'll want
to visit their website to learn of the amazing depth and breadth of filter
synthesis tools available. They also have many application notes that might be
useful. A free trial and university versions are available...
 Anatech Electronics, an RF and microwave
filter company, has introduced a new line of suspended stripline and waveguide type
RF filters. Also, Sam Benzacar wrote as part of his May newsletter an article entitled
"Wi-Fi
Marches Forward, Unnoticed," which focuses on how advances in Wi-Fi are
being made to address contemporary needs, while the news industry and
subsequently users are largely unaware of the changes. 802.11ax, rebranded as
Wi-Fi 6 by the Wi-Fi Alliance, provides data rate increases up to 37% over
802.11ac. Increased range and higher device connection counts, needed to cover
large venues without extenders, is a big part of the performance enhancement...
 OK, class, put your books away and take out
a pencil. Spread your chairs out because we're going to have a short test today.
A collective sigh permeates the room. Remember those days? I still have nightmares
over those moments, and they were decades ago for me. At least this "Electronic
Noise Quiz" from the August 1962 edition of Popular Electronics
won't affect your GPA. Sometimes PE's quiz illustrations are kind of hard to
interpret, but this one does a pretty good job (except item 'E', but I'm not
telling what it is since nobody helped me). You will need a fairly diverse
background in consumer type electronics to do well, and having a few gray hairs
will probably help as well. Good luck. BTW, my score was a somewhat embarrassing
80%...
 "SpaceX CEO Elon Musk tweeted out a picture
of 60 of SpaceX's secret
Starlink satellites packed into a Falcon rocket,
ready to be launched this week in the first major test deployment of SpaceX's satellite-based
internet intrastructure. Starlink Satellites Ready for Launch On Twitter this week,
Elon Musk showed off 60 of SpaceX's new Starlink satellites being packed onto a
Falcon rocket in advance of this week's mission to test the deployment of the satellites
into low Earth orbit. In a series of tweets, Elon Musk showed off the satellites
along with a similar picture of SpaceX's Starman just prior to its launch into
space last year..."
 KR Electronics designs and manufactures high
quality filters for both the commercial and military markets. KR Electronics' line
of filters includes lowpass,
highpass, bandpass, bandstop and individually synthesized filters for special applications
- both commercial and military. State of the art computer synthesis, analysis and
test methods are used to meet the most challenging specifications. All common connector
types and package form factors are available. Please visit their website today to
see how they might be of assistance...
Tuesday 21
 This "Recent Developments in Electronics"
from a 1960 issue of Electronics World had a lot of
antenna news that included a retarded surface wave antenna with high gain and
low silhouette for use in airborne early warning radar as well as ground based and
shipboard radar, a pair of 60-foot tropospheric scatter antennas that are specially
mounted at opposite ends of a 180-mile long section of the Gulf of Mexico, and a
104-foot-long rotating 50-ton radar antenna used for the SAGE early warning system.
Also reported was Westinghouse Electric's airborne Stratovision for broadcasting
educational television programming to rural areas out of reach of existing
towers...
 Empower RF Systems is a global leader in
power amplifier solutions. Empower RF Systems is an established and technologically
superior supplier of high power solid state RF & microwave amplifiers. Our offerings
include modules, intelligent rack-mount amplifiers, and multi-function RF Power
Amplifier solutions to 6 GHz in broadband and band specific designs. Output
power combinations range from tens of watts to multi-kilowatts. Unprecedented size,
weight and power reduction of our amplifiers is superior to anything in the market
at similar frequencies and power levels...
 Any Star Trek fan would immediately recognize
this as Mr. Scott's "transparent aluminum." "In materials science, achromatic optical
components can be designed with high transparency and low dispersion. Materials
scientists have shown that although metals are highly opaque, densely packed arrays
of metallic nanoparticles with more than 75% metal by volume can become more transparent
to infrared radiation than dielectrics such as germanium. Such arrays can form effective
dielectrics that are virtually dispersion-free across ultra-broadband ranges of
wavelengths to engineer a variety of next-generation metamaterial-based optical
devices ..."
 The 1950s was a time when futurists were predicting
that
domestic robots would be common place items in households. By the turn of
the century, mankind, freed from the drudgery of manual labor, would have plenty
of time for recreating, resting, and sitting around brainstorming the next big
thing. Here it is 12 years into the new century and at the most, a fraction of a
percent of the population even has a Vroom robotic floor vacuum - and it looks
nothing like a human. This comic from the November 1957 Popular Electronics
exemplifies the visions of the last century. Now, maybe by the end of the 21st
century we'll finally be there...
 Rohde & Schwarz introduces their "This
Changes Everything" promotion which allows customers to purchase its
oscilloscopes, spectrum analyzers, power supplies and power analyzers each fully
equipped with the maximum bandwidth, channels, inputs, memory interfaces and
signal generation for one affordable, unrivaled price. The promotion runs May 20
through December 31, 2019. Customers who might need to budget for future
upgrades based on design needs can maximize their investment up front, making
purchasing easier and less expensive. Save up to $10,000 on full-solution
instruments...
 "U.S. Air
Force says a ground-based laser downed multiple test missiles over New Mexico. A
successful ground test has moved the U.S. military one big step closer to putting
anti-missile lasers on its aircraft. A ground-based laser shot down 'several' missiles
in flight during an April 23 test at the White Sands Missile Range in New Mexico,
Air Force officials said. Run by the Air Force Research Laboratory, or AFRL, the
test was part of the
Self-Protect High Energy Laser Demonstrator,
or SHiELD, a program intended to protect aircraft from incoming missiles. AFRL
officials said security reasons prevented them from saying how many missiles
were downed in the test. The laser that the Air Force lab used for the test was
ground-based...
 Innovative Power Products (IPP) has over
30 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband couplers, combiners, resistors, baluns, terminations
and attenuators are fabricated using the latest materials and design tools
available, resulting in unrivaled product performance. Applications in military,
medical, industrial and commercial markets. Take a couple minutes to visit their
website and see how IPP can help you today...
Monday 20
 Sometime around 1980, while stationed at
Robins AFB, Georgia, I finally succumbed to the peer pressure of other more sophisticated
audiophiles in the barracks and bought a "real" stereo. Unlike my roommate who had
a full compliment of rack-mounted gear, my meager enlisted military pay only allowed
for a mid-grade instrument. The solution was a
Sansui TA-300 Integrated Tuner Amplifier. It put out a whopping 30 watts per
channel, but unlike my existing radio (a Readers Digest 800-XR), those 30 watts
were nearly distortion free when driving good speakers. Having only the pathetic
5 W speakers that came with the 800-XR, I designed a set of speakers rated for
60 W, and built the enclosures myself in the base woodshop. Unfortunately, in
preparation for a household move about 20 years ago, I sold the Sansui and the
speakers...
 In
case you forgot to put it on your calendar, today, May 20th, is
World
Metrology Day. To commemorate the occasion, this is the day that the official
definition of the kilogram is being changed from a physical cylinder of metal to
the equivalent mass (recall Einstein's E=mc2) derived from a photon energy-to-frequency
ratio measured to its most precise value. Per the new definition, the magnitude
of a kilogram would be "set by fixing the numerical value of the Planck constant
to be equal to exactly 6.626 069… × 10–34 when it is expressed in the
SI unit s–1 m2 kg (J s)..."
 This is a nice short article covering the
calculation of inductances for coils wound on cores and wire sizes. It appeared
in a 1932 issue of Short Wave Craft, but of course inductance has not changed
since then so it is still relevant. The author recognized that standard formulas,
although concise and accurate, are sometimes difficult to work with when calculations
for a large number of values is needed for a particular circuit design. To address
the situation, he presents a handy nomograph, chart, and a table of typical values.
He also introduces a rarely seen term "Nagaoka's correction factor*" for skin
effect. A smartphone app, a spreadsheet, or a desktop computer program would be
used today to calculate inductance...
 "The Indian Institute of Science claims the
first enhancement-mode (e-mode) operation of aluminum gallium nitride / gallium
nitride (AlGaN/GaN) high-electron-mobility transistors
(HEMTs) using p-type aluminum titanium oxide (AlTiO) gate insulation. The
metal-oxide-semiconductor (MOS) gate stack combined the high-k dielectric
properties of TiO2 (k greater than 60) with the p-type properties supplied by
Al2O3 doping (k ~9). The Al2O3 substitutes the 2Als on Ti sites and the 3Os have
a deficit of one vacancy that is doubly positively charged. The charged O
vacancy can release two holes, which can subsequently be reabsorbed by uncharged
O vacancies..."
 5G is providing plenty of challenges for filter
designers. The issue is probably no so much achieving narrow bandwidths with extremely
sharp rejection regions as implementation in available media. Peter Matthews, of
Knowles Precision Devices, as an article entitled, "Approaching the 5G mmWave Filter Challenge,"
on the Microwaves & RF website that discusses some of the issues. "In the world
of LTE, developers are very familiar with the available filtering technologies
that work, namely surface acoustic wave (SAW) and bulk acoustic wave (BAW)
filters. These filters cover a range of frequencies up to 6 GHz, come in small
sizes and offer good performance-to-cost trade-offs..."
Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly
for design engineers needing low volume or prototype multi-layer printed circuit
boards. Free Passive Components: Bittele
Electronics is taking one further step in its commitment of offering the best service
to clients of its PCB assembly business. Bittele is now offering common passive
components to its clients FREE of Charge...
Sunday 19
 This week's crossword puzzle will keep you
busy for a while. Since 2000, I have been creating
custom engineering- and science-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...
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
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