See Page 1 |
2 |
3 |
4 | of the April 2020 homepage archives.
 If you are going to write an article about
etching crystals for radio frequency circuits, having a last name
like Gene Brizendine's couldn't be much better. It just sounds like a mineral or
a compound (benzidine, etc.). Amateur radio operators have for a long time adjusted
the resonant frequency of their crystals by either grinding or chemical etching.
Mr. Brizendine recommends etching as a more controllable method that does not
reduce the quality of the crystal like improper grinding can do. Ammonium bifluoride
is mentioned as the etchant. It is said to have cost about $1/pound in 1954, and
sells on Amazon today for about $23/pound. According to the BLS Inflation Calculator,
$1 in 1954 is the equivalent of about $9.60/pound in 2020, so the price has gone
up considerably - not sure why. Of course it could be that the modern solution
is more concentrated than that used by the author...
 The other day a song titled "Western
Union" played on my local over-the-air oldies radio station. It was released
by the group The Five Americans in 1967. I've heard it many times before, but it
finally occurred to me that the use of Morse code-like symbols in the refrain made
it a perfect candidate for a spot here on RF Cafe. The full lyrics of "Western Union"
can be found at the bottom of the page, but notice the "Dah-Dit-Dah-Dit-Dah" repeats
in the refrain. Even though I'm a licensed (as of 2010) Ham, my shameful (according
to some veterans) status as a post-Morse-code era did not require demonstration
of code proficiency. As such, my lack of a Morse code deciphering ability required
that I rely on an online translator for considering what the code might be. Depending
on how you separate the dits and dahs, the string of characters can be interpreted
as TETET (- . - . -), TAA (- .- .-), KA (-.- .-), NK (-. -.-), CT (-.-. -) or other
combinations, none of which seem to mean anything in particular...
 SF Circuits' specialty is in the complex,
advanced technology of
PCB fabrication and assembly, producing high quality multi-layered
PCBs from elaborate layouts. With them, you receive unparalleled technical expertise
at competitive prices as well as the most progressive solutions available. Their
customers request PCB production that is outside the capabilities of normal circuit
board providers. Please take a moment to visit San Francisco Circuits today. "Printed
Circuit Fabrication & Assembly with No Limit on Technology or Quantity."
 Andrei Muller and his associates are now
offering their revolutionary 3D Smith Chart free to university students. The 3D Smith Chart
tool is a completely reconfigurable and very easy to install software program operating
in Windows and programmed in Java for high frequency engineering. The 3D Smith Chart
tool includes starting 2019 negative capacitance and frequency display, added to
the previous negative resistance features. The tool contains two modes: Analysis
Mode (S-parameters Touchstone files based) and Design Mode - Both include 2D and
3D Smith Charts in Z/Y (impedance / admittance) versions. Slide shows and videos
are provided, along with a detailed description and instructions. 3D Smith Chart
literally adds a whole new dimension to impedance and admittance analysis by transforming
a plane into a sphere, thereby exposing information not visible in Phillip H. Smith's
original version (itself a game changer). For the free trial version please contact
them via the Contact
form or on
3dsmithchart@gmail.com !
 Odyssey Technical Solutions, with more than 60
employees in our new 32,000 ft2 facility in Round Rock, Texas, and having
done 50,000 repairs, is showing no signs of slowing down. In fact, we currently
have openings for qualified RF Repair Technicians. Procedures and processes developed
over many years are designed for repeatable success in our repairs and to give our
customers a high level of confidence that we will do it right the first time. Our
employees bring a variety of experiences to our company, which has helped us grow
by incorporating their experiences into what we do. Meeting and exceeding customer
expectations is the top priority for Odyssey, our goal is to provide the highest
quality repair each and every time. With legendary customer service helping to drive
customer satisfaction on a daily basis...
ERZIA serves critical aerospace and defense missions by designing and manufacturing
RF, microwave, and mm-wave amplifiers,
integrated assemblies operating from low frequencies up to 100 GHz, and by
providing high reliable satellite communications. The company was founded in 2002
to become a worldwide reference of advanced engineering, performance, reliability
and ruggedness. Their catalogue of standard amplifier modules comprises more than
100 different models, having also a high capacity of customization for amplifiers
and integrated assemblies. Some of products have space heritage and are used in
aerospace, commercial, military and scientific systems, having a wide range of final
applications.
 Prior to the advent of personal computers
and handy-dandy antenna design software like EZNEC, determining the effects of varying
parameters - element spacing, angles and length, ground plane distance and extent,
feedpoint impedance, the presence of conductive structures, etc. - it was necessary
to make a series of often complex mathematical calculations and ultimately perform
real-world measurement. Huge amounts of time would be invested in the design and
verification process. It has been know for a long time that the distance an antenna
sits above a ground plane has a significant effect on the radiation pattern - particularly
the vertical pattern. The information provided in this 1954 Radio & TV News
magazine article undoubtedly required many hours to assimilate and required someone
(author William Harrison) with a lot of knowledge in the science/art of antennas.
While some empirical testing is still needed for critical applications, in most
cases these days the results of computer simulations suffice...
"Copper-Mountain-Technologies-RF-Basics-Webinar-4-22-2020.htm" Copper Mountain
Technologies (CMT) will be presenting a free "Copper-Mountain-Technologies-RF-Basics-Webinar-4-22-2020.htm"
RF Basics Webinar." This webinar will touch on the basic concepts which underlay
the operation of a Vector Network Analyzer. What does it really measure? What are
the key components? What are its limitations? How does one compare one analyzer
to another? What are the key specifications? We'll take a brief look at the evolution
of VNA design over the years to understand how a state-of-the-art VNA is USB based
without an embedded operating system. The viewer should come away with an intuitive
understanding of VNA operation and how best to use this important measurement tool.
It will be taking place on Wednesday, April 29, 2020, at 10 AM EST.
 "Intuitive Machines, under contract to carry
NASA science instruments to the moon on a privately-developed robotic spacecraft,
said this week its first commercial lunar mission will target landing in October
2021 near a deep, narrow valley named Vallis Schröteri. The startup company, based
in Houston, announced Monday the landing site for its first
lunar landing mission. Vallis Schröteri is located in on the upper
left part of the moon's near side, as viewed from the northern hemisphere on Earth.
Scientists think the channel-like valley, or rille, has volcanic origins. The rille,
also known as Schröter's Valley, likely formed from a collapsed volcanic lava tube..."
 Author Murray Scot published a piece a couple
years ago entitled, "Tanner Beijing's New National Intelligence Law: From Defense to Offense,"
on the Lawfare website (for the record, Lawfare is not a conservative website by
any stretch of the imagination). Its content is relevant in regard to the worldwide
pandemic of a killer virus that originated in Wuhan, China. He states in part: "China's
National Intelligence Law, enacted on June 27 with unusual speed and limited public
discussion, is a uniquely troubling milestone in Beijing's four-year-old campaign
to toughen its security legislation." Further, "The law also perpetuates the Xi
Jinping leadership's narrative that all foreign contacts should be regarded as suspicious;
that Chinese citizens engaged in such contacts do so at the risk of surveillance
and harassment by their own government; and that the Chinese Communist Party-state
is now strong enough to call for intelligence cooperation even from foreigners doing
business in China." Remember this when you try to get
N95 masks.
"anatech-electronics-april-newsletter-4-22-2020.htm"
 Sam Benzacar of Anatech Electronics, an RF and
microwave filter company, has published his April newsletter that features his short
op-ed titled "5G SARS-CoV-2 Conspiracy Theories Abound," which would be funny
if it wasn't so serious. In the past couple weeks I have posted news items about
crazies in Europe who have been setting 5G cell towers - or sometimes any cell tower
- on fire after an article from Belgian newspaper Het Laatste Nieuws published an
article by Dr. Kris Van Kerckhoven entitled, "5G is life-threatening and no
one knows it." An Internet search turns up scores of stories: BBC, Forbes, The Verge,
Business Insider, Twitter thread. Also included in the newsletter are a few headlines
including stories about the big money shelled out by carriers for millimeter-wave
spectrum, autonomous vehicles, 5G and Iot, and TracFone being investigated for fraud...
Triad RF Systems designs and manufactures RF power amplifiers and systems. Triad RF Systems
comprises three partners (hence 'Triad') with over
40 years of accumulated knowledge of what is required to design, manufacture, market,
sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA, bi-directional,
and frequency translating amplifiers are available, in formats including tower mount,
benchtop, rack mount, and chassis mount. "We view Triad more as a technology partner
than a vendor for our line-of-sight communications product line." Please check to
see how they can help your project.
 When you think about it, the speed at which
a human being is able to accurately copy
Morse code is limited by the same kinds of processes that limit
the speed at which binary data can be sent between electronic transceivers (modems).
Noise introduced into the signal at both the transmitting and receiving ends or
in the transmission path connecting the two, degrades the ability of the receiver
(electronic and human) to discern between a "1" and a "0." It can take the form
of electrical or audio interference and distortion. Phase noise in the electronic
realm is sort of the equivalent of an irregular sending human hand that cannot maintain
equal dwell times for dits and dahs, thus making the recognition of characters error-prone.
The operational speed of circuitry on an electronic assembly can also limit the
speed at which Morse code can be copied similar to how a particular person's gray
matter can limit his comprehension speed...
 "The mass building and deployment of
commercial satellites is likely to bring about serious threats
to U.S. national security and global interests, as fellow countries quickly work
to expand their stakes in space, a new study published by researchers with the Institute
of Defense Analyses (IDA) has revealed. Published in the National Defense University's
Joint Forces Quarterly, the study noted that while the spike in satellites will
help to better inform US service members across the board during military operations,
the build-up will also have some drawbacks. 'The effects of proliferated constellations
will not be confined to the commercial sector. The exponential increase in the number
of satellites on orbit will shape the future military operating environment in space,'
reads the study..."
 Phil Salas, AD5X, published an extensive
review of the
NanoVNA vector network analyzer in the May 2020 issue of the ARRL's
QST magazine. Unfortunately, the article is not available to non-members,
but if you are a member or know someone who is, it would be worth reading. He compared
measurements by the NanoVNA with those obtained using an Array Solutions VNAuhf,
which yielded very favorable results. There are many knock-offs of the NanoVNA available,
which is typical since most of these low-cost, high-performance electronics devices
are built using widely available block-level components that make replication relatively
easy. Variations in the quality of coaxial connectors, internal batteries, switches,
etc., can and often does make a big difference in the quality and ruggedness of
the equipment you buy. Firmware and support software can vary significantly as well.
It's a roll of the dice to some extent...
 "Our first complete column devoted to the
subject [of v.h.f. and u.h.f. signal variation], presenting material similar
to that which follows, was withheld from publication at that time in compliance
with censorship." That is an amazing statement from a time when almost any form
of technical information that was not already public knowledge was withheld for
the sake of the war effort. Nothing that might even remotely give the enemy an edge,
and consequently possibly harm our troops, got past the government censors at the
War Department. Most citizens and even media editors willingly complied. Compare
that with today's 5th column traitors at most of the media outlets that not only
can't wait to publish information that will aid and abet our country's enemies,
but have been known to manufacture stories in order to make the U.S. look bad...
"Southwest-Antennas-Omni-Directional-4x4-MIMO-Antennas-Aircraft-Helicopters-UAVs-4-20-2020.htm"
 Southwest Antennas, a leader in rugged RF and
Microwave antenna products and accessories for tactical radio systems, is pleased
to announce the release of two new antennas to meet the demand for "Southwest-Antennas-Omni-Directional-4x4-MIMO-Antennas-Aircraft-Helicopters-UAVs-4-20-2020.htm"
multi-port MIMO antenna solutions for medium range aircraft performing ISR missions.
These antennas are built off of Southwest Antennas' existing, field-proven MIMO
antenna technology with design improvements specifically for these new mission requirements.
Our engineering team has added a new flange mount base for secure mounting, in addition
to reinforcing the antennas for the higher altitude and airspeed achieved by medium
range military turboprop aircraft that are commonly used for surveillance, patrol,
search and rescue, and transport operations. With a conservative airspeed rating
of up to 374 MPH these MIMO antennas...
 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 265,628 products from more than 1380
companies across 313 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.
 Waaaay back in the mid-1980s when I first
became aware of
Digi-Key, it was one of the relatively few electronics component
suppliers that had a large on-hand stock of commonly used parts and provided fast
shipping. Places like Newark Electronics and Allied Electronics also provided good
service, but Digi-Key usually offered lower prices than the others. By the 1990s,
I was placing orders at least weekly during circuit design projects. Digi-Key was
founded in 1972 in Thief River Falls, Minnesota - the town that for many years often
had the country's lowest recorded daily temperature. This 1/4-page advertisement
appeared near the back of a 1974 issue of Popular Electronics magazine. By the mid-1990s,
their multipage ads in electronics magazines were proliferating like today's Harbor
Freight ads. Here's a bit of trivia I just learned: The company's name is a reference
to the "Digi-Keyer Kit," a digital electronic keyer kit that founder Ronald Stordahl
developed and marketed to amateur radio...
 Hydroxychloroquine
has been in the news a lot as a historically safe virus combatant. Its origins reach
back to the 1700s in the form of quinine as a malaria treatment. Paradoxically, U.S. medical "experts"
avoid the topic, urging patience until a big-pharma solution is available (at big
$$$ per dose). Regardless of which side of the debate you fall on, you might be
interested to know that the "tonic" part of the popular "gin and
tonic" mixed drink was a tonic of quinine. It was mixed with gin by soldiers
to mask the horrible taste of the quinine because they avoided consuming it in raw
form, preferring to risk infection. And now you know...
The
Rest of the Story.
Nova Microwave is a leader in technically differentiated electronic and radio
frequency Ferrite Circulators and Isolators that connect, protect and control critical
commercial and military wireless telecommunications systems. Our staff is dedicated
to research and development of standard and custom design quality Ferrite Circulators
and Isolators from 380 MHz to 26.5 GHz. Available in single or multi-junction
topographies, the Nova Microwave product line of is specifically designed for use
in varied environmental and temperature extremes.
 "Tokyo is now a next-door neighbor-thanks
to the magic of short-waves." That statement was made in a 1935 edition of Short
Wave Craft magazine after the American Telephone and Telegraph (AT&T) company
completed its wireless phone (voice) link between the U.S. and Japan; which is the
first 'T' in AT&T. Most people today would probably have a hard time guessing
that the
second 'T' in AT&T stands for 'telegraph.' Its surprising
that the name has not been changed to reflect the outdated-ness. Western Union sent
its final telegraph in 2006. Another news headline a couple years ago reported on
India sending its final official telegraph message...
 Axiom Test Equipment, an electronic test equipment
rentals and sales company headquartered in San Diego, has published a blog post
titled "Steering UAVs Clear with Digital Circuit Testing." This blog is
the second in a series of three planned articles that will take a closer look at
the global fascination with UAVs and how they are used, whether for farming or for
warfare, and some of the best test tools that can be applied to ensuring the best
UAV performance possible. The OQ-2A, one of the first remote-controlled target drones
produced in the U.S., was made by the Radioplane Company owned Hollywood actor Reginald
Denny. Norma Jeane Mortenson, aka Marilyn Monroe, was discovered there. "Drones
and unmanned aerial vehicles (UAVs) are being used in a growing number of commercial,
civil, industrial, and military applications. They are currently used for many security
and surveillance task...
Odyssey Technical Solutions, with more than 60
employees in our new 32,000 ft2 facility in Round Rock, Texas, and having
done 50,000 repairs, is showing no signs of slowing down. In fact, we currently
have openings for qualified RF Repair Technicians. Procedures and processes developed
over many years are designed for repeatable success in our repairs and to give our
customers a high level of confidence that we will do it right the first time. Our
employees bring a variety of experiences to our company, which has helped us grow
by incorporating their experiences into what we do. Meeting and exceeding customer
expectations is the top priority for Odyssey, our goal is to provide the highest
quality repair each and every time. With legendary customer service helping to drive
customer satisfaction on a daily basis...
 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. Products are designed and manufactured in the USA.
 Here are a couple more electronics-themed
comics from vintage Radio-Craft magazines. Artist Frank Beaven, who created
a huge number of comics and advertisements (e.g., Eveready batteries, Zippo lighters)
for technical and other types of publications (Saturday Evening Post,
New Yorker, Esquire), did both of them. Beaven must have a fan
base since many examples of his drawings are offered for sale on eBay. Most of his
comics credit reader suggestions as the basis for the subject. I have to admit to
not really "getting" the gag in the top comic. Maybe Sinatra's voice strained the
frequency response of simple tabletop radios of the day. The bottom comic is one
of a series titled "Radio Terms Illustrated," in this case "High Potential." I'll
be posting a few others in the coming months...
"Berkeley-Nucleonics-Academy-Continuing-Education-Program-1-26-2020.htm"
 Berkeley Nucleonics Corporation (BNC - like
the connector) offers several short courses on RF, Test & Measurement, and Nuclear
technology to allow students and technical staff entering the field to quickly develop
a basic understanding of the principles involved. "Berkeley-Nucleonics-Academy-Continuing-Education-Program-1-26-2020.htm"
BNC Academy's online learning is a popular way to maintain currency in your field
while not requiring time away from critical project activities. Courses may be completed
online and are supplemented with downloadable materials. Titles such as "RF Boot
Camp," "Demystifying Phase Noise Measurements," and "Nuclear Radiation 101" are
among the offerings. Completion certificates are issued and onsite training is also
available. It is possible to look at previews of upcoming courses on BNC Academy
right now.
 Magnetic amplifiers (aka "mag amps") use
a property of saturated core inductors (saturable reactors) to obtain signal amplification
via a transformer-type plus diode-assisted voltage multiplication.
Magnetic amplifiers were preferred over vacuum tube amplifiers
in some circuits because they do not require a high bias voltage, are generally
smaller in size, are quite robust and are practically immune to microphonics. Their
biggest limitation is bandwidth. The high number of turns in the core provides a
lot of interwinding capacitance so the self-resonant frequency is in the low megahertz
range. Additionally, the need for the magnetic amplifier reactor to operate in a
saturated condition further imposed a limit on the frequency response. Even today,
there are some critical applications that exploit the fool-proof and ultra high
reliability nature of the magnetic amplifier. This article goes into the details
of operation both as amplifiers and as bistable multivibrators...
 This has always been one of my favorite
Calvin & Hobbes comic strip episodes. Calvin's father,
a patent attorney, is famous for providing zany explanations to Calvin's inquiries
about physics, astronomy, and other science subjects which he knows nothing about.
In this comic, Calvin is riding in the car over a bridge with "Weight Limit 10 Tons"
on it. He asks his father how the limits are determined. His father, whose name
has never been divulged (neither first name nor last name), replies with a typically
hilarious version of what goes into the weight limit calculation. Read on for explanations
on where babies come from, why old photographs are in black and white even though
much older paintings are in color, the sunset, how a light bulb works, and even
Relativity, amongst other things. Bill Watterson was truly a genius...
 In spite of "5G" having been in the news
for nearly a decade, many (maybe most) people do not really know what it is. 5G
is not simply faster 4G; it is a whole new paradigm if ubiquitous wireless interconnectivity
of everything at data speeds formerly achievable only with wired systems. Pasternack
has an article on the Microwave Product Digest (MPD) website entitled,
"5G: Sorting Fact from Fiction," that helps clarify the subject
somewhat. As is often the cases - and its not a bad thing - the article is partly
an infomercial for Pasternack products. It begins, "So much has been written about
5G that it's impossible for mere mortals to form their own conclusions about what
it will actually achieve. Although it's far too early to know for sure, this hasn't
stopped the continuing deluge of marketing hype throughout the industry promising
something for everyone. In the hope of providing some clarity on these issues, this
article addresses some of the primary areas of confusion..."
 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.
 April 19 commemorates a special birthday
here at RF Cafe as explained in 39 and 74 Across. You can calculate her age by solving
these two equations in two unknowns: Her Age = Her Year of Birth - 1902, and My
Age = Her Year of Birth - 1900. Actually, you don't need to know my age to solve
the first equation. This tech-themed crossword puzzle contains only clues and terms
associated with engineering, science, physical, astronomy, mathematics, chemistry,
etc., which I have personally built over nearly two decades. Many new words and
company names have been added that had not even been created when I started in the
year 2002. 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 star like Hedy Lamarr or a geographical location like
Tunguska, Russia...
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. Some quoted items have been shortened
to save space. About RF Cafe.
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