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4 of the February 2019 homepage archives. Friday 22
 Ask and ye shall receive... at least sometimes.
I posted a request for an article by science fiction writer Arthur C. Clarke, of
2001: A Space Odyssey fame, describing a
geostationary satellite system that was published in the October
1945 edition of Wireless World magazine. Thanks to RF Cafe visitor Terry
W., from the great state of Oklahoma, it is now available for everyone to enjoy.
Clarke was not just a sci-fi writer, but also an educated visionary and card-carrying
member of the British Interplanetary Society, who proposed many technological solutions
to issues of his day. In this instance, the challenge was developing an efficient
means to distribute TV signals across Europe and the world. Clarke's calculations
for the necessary number of repeater towers proved that concept impractical, so
he proposed using modified surplus German V2 rockets to launch Earth-orbiting "artificial
satellites," powered...
 Analog Devices and Arrow Electronics will
be presenting a free webinar on March 21st titled, "Deep Learning for Radio Frequency Systems." Deep learning within
RF shows promise for dealing with a congested spectrum by enhancing reliability
and simplifying the task of building wireless systems. This webinar will discuss
a software defined radio that can perform real-time DSP and deep learning with an
NVIDIA GPU and an Analog Devices front end. We'll discuss system performance, training
of RF data, software used to deploy algorithms, and take a deep dive into one application.
Attendees will learn: Applications of deep learning for systems and signals...
 Rohde & Schwarz USA (R&S USA) has
published a white paper titled, "An Introduction to EMC Amplifiers." This white paper describes
not only the basics of EMC amplifiers, but also intricacies, discusses parameters
and characteristics that have the greatest influence on amplifier performance. It
provides a technical overview of EMC amplifiers as well as a practical discussion
of how amplifier class, compression points, VSWR, foldback, etc. impact amplifier
performance in real-world scenarios. Broadband amplifiers are necessary for generating
the field strengths required for most EMC radiated immunity tests. This whitepaper
provides a brief overview of the role of amplifiers in EMC testing as well as a
discussion of the parameters and characteristics which have the greatest influence
on amplifier performance...
 "A team of researchers from Germany and Argentina
have devised an ultra-thin planar Hall effect (PHE) sensor capable of detecting
very
faint magnetic fields even when flexed or wrapped around a wire.
In a paper titled "Highly compliant planar Hall effect sensor with sub 200 nT
sensitivity" published in Nature's npj Flexible Electronics journal, the researchers
describe a very simple fabrication process, whereby asymmetrical Permalloy (Py)
Hall crosses just 20 nm thick are patterned on 6 µm-thick PET foils before
being magnetized through multiple magnetic field sweeps (between ±3 mT)..."
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...
Thursday 21
 Did you know that at least originally the
term "Wire-Wrap" was - and maybe still a - registered trademark of Gardner-Denver
Company? Kynar insulation, whose full name is
Kynar polyvinylidene fluoride (PVDF) resin, is most likely a familiar
type of insulation due to its widespread use on wire-wrap wire. It had very recently
been introduced to the electronics world when this advertisement appeared in a 1964
issue of Electronics magazine. The contemporary name used by its manufacturer,
Arkema, is Kynar500®, and the coating's use has expanded well beyond the electronics
industry into architectural and mechanical coatings. I did a LOT of manual wire-wrapping
on Mil-Spec equipment while working as a technician at Westinghouse Oceanic Division...
 ARRL's
HF Dipole Antennas for Amateur Radio, just released a few days
ago is a collection of 20 HF dipole antenna designs published in QST, ARRL's membership
journal, between 2000 and 2017. It includes innovative antenna projects for single-band
and multiband antennas, as well as antennas for portable applications. Some of the
featured antennas are: "An Easy-to-Make Three-Band Dipole for ARRL Field Day," "A
Field-Portable Multi-Band Rotatable Dipole Antenna," "A Small, Portable Dipole for
Field Use A Portable Twin-Lead 20-Meter Dipole," "The NJQRP Squirt Multiband Antennas,"
"A Shortened 60 Meter Dipole That Also Covers 15 Meters," "A Compact Multiband Dipole,"
"A Folded Skeleton Sleeve Dipole for 40 and 20 Meters..."
 Short wave radio was a boon to both professional
and amateur radio operators because of its ability to be received over longer distances
using significantly lower transmitter power. The problem was (and still is) that
short wave bands typically suffer from atmospheric ionization
effects that vary depending on time of day, local weather, solar activity, pollution,
and other phenomena. Long wave's advantage was that although it required higher
power and longer antennas, it was (and is) extremely reliable. For other than the
most critical applications, idiosyncrasies of short wave communications were accepted
as the price of more convenient and lower cost operation. Widespread adoption of
short wave communications brought extensive studies and characterization of atmospheric
influences in particular frequency bands. Discovery of distinct 'F' layers (regions)
in the ionosphere and their effects on radio transmission has allowed...
 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. Whitepaper topics include careers, manufacturing,
and engineering, while magazine titles include
Microwave Engineering Europe,
Electronic Design, and
Microwave Product Digest. Note: I earn a few pennies (literally)
when you download one of these or the many other pubs available, so please help
yourself ...
 Sam Benzacar, of RF and microwave filter company
Anatech Electronics, has written as part of his February newsletter this piece titled,
"'Mysterious' Cuban U.S. Embassy Weapon: It Wasn't Crickets." Sam
keeps abreast of all the latest news in the wireless world, which is not unexpected
given his company's long-time involvement in helping others make their products
play well together in an increasingly crowded electromagnetic spectrum - both licensed
and unlicensed. Beginning in late 2016, news reports told how many U.S. and Canadian
embassy staffers and their families told of hearing strange sounds in their heads
and experiencing nausea and headaches. I read many of them. Of course no conclusive
evidence as to the source has ever been discovered since officials of the western
hemisphere's only Communist nation (Cuba) allows...
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 20
 Webinar presentations have become a huge part
of ongoing training for engineers and managers - both by attending and conducting
them. Your opportunity for becoming well-known in the industry can be greatly enhanced
with an effective, attention-grabbing production as the star of a webinar (of course
a bad performance can sink you just as easily). Register for your free OnDemand
webcast now titled, "How to Become a Superstar Webinar Presenter." The last thing you
want to hear is that your presenter was dull and people weren't engaged. A bored
audience means low viewing time, low content retention, and, sometimes, total brand
rejection. Don't let that happen to you! In this on-demand webinar, you'll learn
how to find great webinar talent and best practices to make your existing presenters
more engaging and presentations more fun...
 I'm having a hard time writing this with
my eyes rolled back in my head. The last time I experienced this level of overwhelmedness
was probably the third or fourth week of my feedback and control class at UVM. Even
though electricity and magnetism shares many complimentary and parallel concepts,
for some reason thinking in terms of
magnetics when describing amplifiers, mixers, modulators, etc.,
has always caused brain freeze. Maybe it has to do with an ingrained bias due to
my earliest dealings with circuits being from a technician background before earning
an engineering degree. The equations of electric fields and magnetic fields are
very similar so that helps lower the barrier a bit. An engineer I worked with once
had the uncanny ability to comprehend time domain waveforms in the frequency domain,
and vice versa, when viewing an o-scope or spectrum analyzer display. Sure, simple
things like sine waves or square waves can be recognized by most people who have
been in the field for a couple years, but this guy's ability...
 Withwave's
vertical launch 1.85 mm connectors are specially designed
for solderless vertical PCB launch on test & measurement board. These connectors
have excellent electrical transition performance up to 67 GHz as well as reduce
installation time by eliminating soldering. It is the best solution available for
easy use in test & measurement boards, high speed digital test boards. We solve
your performance and cost problems...
 This chapter from the 1949 edition of the U.S.
Navy's Electrician's Mate 3 course (NAVPERS 10548) requires an important
clarification. Current flow in this article is defined as going from negative to
positive, which is opposite of today's convention. Per the text: "Modern
experiments have shown that a current of electricity is really a flow of electrons,
and the direction of flow is from negative to positive." Beginning sometime in the
1960s, concurrent with the great amount of research being done in semiconductor
electronics, the convention of positive-to-negative current flow was adopted, defined
as the direction of positive charge carriers (holes). The negative-to-positive convention
is defined based on the direction of negative charge carrier (electron) flow. I
personally never understood the crisis that retaining the electron flow convention
would have caused, but higher authorities decreed it to be done. We have gone from
+ to - current flow...
 A new application note titled "Network Synthesis Wizard Automates Interactive Matching-Circuit Design"
features the network synthesis wizard in NI AWR software that automates interactive
matching-circuit design, thus reducing design time. Network synthesis is helpful
at the earliest stages of a design to help determine reasonable performance targets
based on device performance limits, device sizing (decisions on active device periphery),
part selection for discrete packaged transistors and other early design decisions.
Available as a free download now...
Tuesday 19
 If you want to know what was really going
on at some point in the past, there is usually nothing more reliable than reading
a print story or advertisement from the era. That way you're getting the news "straight
from the horse's mouth," so to speak, rather than being interpreted or filtered
by some unassociated source. This report on "The Transistor in Industry" was written in 1956 by Mr. Frank
Durat, a product manager at Raytheon, at a time when transistors were first making
inroads for replacing the venerable vacuum tube (valve) which had launched and propelled
the electronics industry since 1908 when Lee de Forest introduced the triode Audion
amplifier. Germanium and silicon were the semiconductor base crystals du jour, and
achieving the requisite purity was a primary concern for advancing the state of
the art for higher frequencies, power handling, and circuit density (for integrated
circuits)...
 Guerrilla RF, a leading provider of high performance
MMICs, today introduces GRF2073-W, a new addition to the company's growing list
of
AEC-Q100 automotive-qualified amplifiers. This ultra-low noise
amplifier is targeted at high-volume applications, with first-stage satellite radio
LNAs and GPS modules being prime examples. It is offered in an industry-standard,
ultra-small 2.0 x 2.0 mm DFN-8 package thus sharing a common pin out with other
infrastructure-class devices from Guerrilla RF. "Guerrilla RF is proud to offer
this new amplifier for automotive applications which addresses an industry need
for a cost-effective, first-stage LNA delivering outstanding RF performance with
low power...
 You've probably heard the old saying regarding
"getting it into gear," when attempting to motivate a company, person, or group
of people who are stuck in an intractable rut to start moving in a new direction.
A couple years ago I ran across a drawing similar to the one shown here. It was
on a technical venue where whoever used it should have recognized that as shown,
the meshed gears would never move due to a rotation direction conflict (see my arrows).
I posted a screen shot of it here on RF Cafe. The scheme as depicted is antithetical
to the concept of motion. In fact, it is the very epitome of being locked in place
with no hope of moving (other than slop between the cogs). Sadly - and I hate to
even draw attention to it - the image shown appeared in the March 2019 issue of
the ARRL's
QST magazine. I know for a fact those guys are way, way smarter
than I am, so how it slipped past the editors is a mystery. BTW, the other entity
eventually corrected its mistake by "unmeshing" the three gears...
 San Francisco Components (SFC) has updated
its
printed circuit board (PCB) turnkey assembly capabilities. Full
turnkey PCB assembly through SFC reduces the customer's responsibility to source
components (and the surrounding issues), manage the bill of materials (BOM), inventory,
and logistics associated that can be encountered when working with a PCB assembly
partner. SFC's turnkey and partial turnkey or consigned assembly options are designed
to meet the individual needs of their customers, depending on how much of the assembly
process they want to manage versus outsource. SFC's turnkey PCB specialists can
help guide customers through the benefits of each approach and ultimately deliver
the optimal product and service...
 "Designed for use in closed HF RFID systems,
PragmatIC's PR1101 and PR1102 flexible integrated circuits (FlexICs) are the first products in the company's ConnectIC family.
Developed using PragmatIC's unique platform of patented technologies, ConnectICs
deliver connectivity solutions at the lowest cost point in the market, claims the
manufacturer, delivering an ultra-thin and flexible solution that can be embedded
into a wide range of substrates, including paper and plastic. The devices reduce
the complexity of inlays by using single layer antennas, delivering a further step
down in cost to brand owners and retailers. These ConnectICs are extremely attractive..."
 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...
Monday 18
 Just about everyone who has worked in the
radar field for a long time is familiar with the name of
Dr. Robert M. Page. He was the first to come up with
the concept of monopulse radar, and he invented the familiar Plan Position Indicator
(PPI) radar display and the RF duplexer which allows one antenna to be connected
to both the transmitter and the receiver. Amazingly, I recently received an e-mail
from Dr. Page's son, John Page. An interest in his father's career combined
with insight that only growing up under the loving care of Dr. Page can provide
has afforded him some unique tidbits of information that many (most, per John) historical
accountings omit. Rather than me summarizing his letter, you will want to read it
yourself as presented below. World War II aficionados will particularly appreciate
the information. John pays homage to his father's co-workers...
 VidaRF, a manufacturer of high performance
RF and microwave high performance isolators, circulators, power dividers, couplers,
and other passive components, is proud to introduce the
VDC-05180-XX line of Directional Couplers with SMA connector,
operating from 0.5 to 18 GHz. It is available with coupling value of 10 dB,
20 dB and 30 dB and can handle up to 50 watts of RF power. VidaRF's
product line includes drop-in, coaxial, and waveguide configurations for many items.
Custom designs available...
 I don't know about the rest of the country,
but this Monday morning in Erie, Pennsylvania, is cold and snowy. That means people
going to work had to shovel their driveways, maybe brush snow and ice off their
windows, and brave hazardous conditions on the streets on the way to the office.
Moods are understandably less than jovial and nerves might be shot. For those of
you who identify with this scenario, these
electronics-themed comics from a couple vintage Radio &
Television News magazines might help assuage your anxieties. The same goes
for those who are in Southern California and managed to arrive safely from a commute
on the notoriously unfriendly highways there. As with many of these old comics,
you have to be privy to the mindset of the day to fully appreciate the topic. TV
repair was big business and people were fascinated with the boob tube innovation
rapidly consuming the attention of domestic dwellers...
 "A team of researchers at the University
of Chicago has developed a circuit platform for the exploration of quantum matter
made of strongly interacting
microwave photons. In their paper published in the journal Nature,
the group outlines their platform and how it might be used. As part of the effort
to create a useful quantum computer, scientists have been investigating superconducting
circuits, which are controllable, have long coherence times and have strong interactions
- characteristics required when studying quantum materials with microwave photons.
The researchers note also that photon losses in such circuits..."
 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...
Sunday 17
 Beginning in 2000, I have created hundreds
of 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 start like Hedy Lamarr or a geographical
location like Tunguska, Russia, for reasons which, if you don't already know, might
surprise you ...
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.
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