See Page 1 |
2 |
3 |
4 | of the April 2020 homepage archives. Friday 6
 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 entitled "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.
Thursday 5
 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 (CMT) will
be presenting a free "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.
 Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his April newsletter that features
his short op-ed entitled "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.
Wednesday 4
 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, 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
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.
Tuesday 3
 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 entitled "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.
Monday 2
 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 entitled "Radio Terms Illustrated," in this case "High Potential." I'll
be posting a few others in the coming months...
 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.
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. Here, Calvin asks how weight
limits are determined for bridges. His father's answer seems a perfect analogy to
what politicians are doing to our economy today in response to the Wuhan Virus pandemic.
I'm surprised this comic has not been a "viral" meme on social media websites -
which maybe it is but I wouldn't know since I do not visit them, so I'll take credit
for it. IMHO, the shutdowns are entirely unnecessary except in the worst areas.
"You never let a serious crisis go to waste. And what I mean by that it's an opportunity
to do things you think you could not do before." - former Chicago mayor...
 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.
Sunday 1
 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.
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