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4 of the February 2022 homepage archives. Monday the 28th
 Gaining a design engineering position with
Google is (or at least was) notoriously difficult because of some of the tests that
are administered - depending on the hoped-for job. Skills in logic, creativity,
problem solving, and fundamental mathematics and science are among the capabilities
that must be demonstrated. IBM was known to have tough entry requirements for customer
field service representatives back in the early days of computers - for technicians
as well as for engineers. "A man who can think his way through a problem can learn
electronics, but a person lacking in analytic abilities will never be a good service
engineer," said an employment manager. Successful candidates could expect to earn
$400/month or more. That was in 1957 dollars, which is $4,041 (~$48k/year) in 2021
dollars (per BLS inflation calculator) - not too awful. Field-experienced, well-qualified
service engineers earned $500 to $750 per month ($5.1k to $7.6k per month, or $61k
to $91k per year)...
 After being in the electronics field
for decades, it is sometimes tempting to think that the world has enough magazine
articles and books covering introductory lessons on the fundamentals of capacitors,
inductors, semiconductors, circuit analysis, testing, etc. While that may be true,
there is value in have a fresh approach to the subjects that include discussions
on modern materials and methods. An article published in 1989 might have had a computer
output plot of impedance vs. frequency on a 16-color, 320x200-pixel
CGA monitor that
plotted data points with "x" and "o" characters. This article by Min Zhang entitled
"Capacitors:
Theory and Application," is a good intro for newcomers. It begins: "Capacitors
are among the most commonly used components on a circuit board. With the ever-increasing
number of electronics devices (from mobile phones to cars), there has been a growing
demand for capacitors...
 Empower RF Systems is proud to announce
the issuance of a new patent entitled "Power
Amplifier System with an Internal Optical Communication Link." Techniques for
implementing an internal optical communication link in a power amplifier system
are disclosed. In one embodiment, the techniques may be realized as a power amplifier
system that includes a panel, an optical link, and a controller. The panel includes
a plurality of signal endpoints and a first optical interface, the first optical
interface being coupled to each of the plurality of signal endpoints. The optical
link is coupled to the first optical interface. The controller is configured to
manage operation of the power amplifier system and is coupled to the optical link
via a second optical interface. The controller communicates with each of the plurality
of signal endpoints over the optical link...
 Bliley Electric Company is one of the relatively
few companies that advertised regularly in electronics magazines during the World
War II era that is still in business today - at least under the same name (Bliley
Technologies now, but still the same base name). While the company is no longer
located in the Union Station Building anymore, it does still live in Erie, Pennsylvania,
only a mile or so from where I Melanie and I last lived there (2021). They still
make crystals today, albeit with different materials and different methods. In fact,
there is a short Bliley company history video on their website, and also this video
from a local TV station showing of the internal workings at Bliley...
 RF Cafe's raison d'être is and always has
been to provide useful, quality content for engineers, technicians, engineering
managers, students, and hobbyists. Part of that mission is offering to post applicable
job openings. HR department employees and/or managers of hiring companies are welcome
to submit opportunities for posting at no charge (of course a gratuity will be graciously
accepted). 3rd party recruiters and temp agencies are not included so as to assure
a high quality of listings. Please read through the easy procedure to benefit from
RF Cafe's high quality visitors ...
 Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
Sunday the 27th
 This custom
Ham Radio themed Crossword Puzzle for February 27th, 2022, is brought to you
by RF Cafe. All RF Cafe crossword puzzles are custom made by me, Kirt
Blattenberger, and have only words and clues related to RF, microwave, and mm-wave
engineering, optics, mathematics, chemistry, physics, and other technical subjects.
As always, this crossword contains no names of politicians, mountain ranges, exotic
foods or plants, movie stars, or anything of the sort unless it/he/she is related
to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska event in
Siberia). The technically inclined cruciverbalists amongst us will appreciate the
effort. Enjoy!
 Anritsu has been a global provider of innovative
communications test and measurement solutions for more than 120 years. Anritsu manufactures
a full line of innovative components and accessories for
RF and Microwave Test and Measurement
Equipment including attenuators & terminations; coaxial cables, connectors &
adapters; o-scopes; power meters & sensors; signal generators; antenna, signal,
spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth &
WLAN testers; PIM testers; amplifiers; power dividers; antennas.
Friday the 25th
 For many years, Radio-Electronics
magazine ran a monthly feature entitled "The Radio Month," which contained news
of industry events, personnel hirings and promotions, product introductions, inventions,
etc. This January 1954 issue introduced something called "microstrip"
to the world. Unlike a lot of new concepts billed as breakthrough, paradigm changing
discoveries that you never hear about again, this one caught on. Practically every
wireless device on the market today has a microstrip substrate of some sort. It
was developed by a division of IT&T called the Federal Telecommunication Laboratories.
Also in the news was a thimble size transistor 100x as powerful as present commercially
available types. Made by Minneapolis Honeywell Regulator Company, it had a whopping
20-watt output (no mention of operational frequency)...
 "In 2020, Professor Teruo Ono and his colleagues
at Kyoto University reported the very first observation of a magnetically controllable,
superconducting diode effect in an artificial superlattice. Their findings,
published in Nature, paved the way for other studies aimed at moving towards the
fabrication of non-dissipative electronic circuits. Working in collaboration with
Professor Ono, another research team at Kyoto University in Japan recently carried
out a study aimed at better understanding the mechanisms underlying the interesting
effect observed two years ago. Their paper, published in Physical Review Letters,
hypothesizes the existence of an intrinsic mechanism that could underpin the superconducting
diode effect reported in their previous work. 'Our group works in collaboration
with Prof. Ono, whose research group performed the pioneering experiment of the
bulk superconducting diode effect,' Akito Daido, one of the researchers..."
 Disneyland opened its gates in Anaheim, California
on July 17, 1955. It was billed as the most high-tech theme park in the world, with
a 'wow' factor on par with the World's Fair extravaganzas. One of its much-ballyhooed
features was the "realistic" jungle safari tour with life-like animal automatons
and authentic 3-D jungle sounds. This 1956 Popular Electronics magazine article,
published less than a year after opening day, highlights some of the equipment and
methods used by artists and engineers to achieve the effects. Of course the equipment
and methods used today make this effort seem less than amateurish...
 Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. Three new filter models have been introduced
- a 100 MHz LC lowpass filter with SMA connectors, a 450-470 MHZ LC bandpass filter
with N connectors, and a
surface mount 2575 / 2680 MHz ceramic duplexer filter. Custom RF power directional
coupler designs can be designed and produced when a standard cannot be found, or
the requirements are such that a custom approach is necessary...
 "L" networks are probably the most common
types of impedance matching networks not just for antennas, but for an relatively
narrowband load. Determining the required values for the network is relatively simple
using well-established equations. Knowing how to use a Smith Chart makes the job
even easier. This article from a 1966 edition of QST magazine presents the equation
approach. If you have access to the May 2013 edition of QST, there is a complimentary
article on L networks that uses the free Smith Chart cross-platform Java software
called SimSmith. If you want to do a little complex number math, try the 1966 approach...
RF Cascade Workbook is the next phase in the evolution of
RF Cafe's long-running series, RF Cascade Workbook. Chances are you have
never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system
cascade parameter and frequency planner that includes filters and mixers for a mere
$45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch
and the format is entirely customizable. It is significantly easier and faster than
using a multi-thousand dollar simulator when a high level system analysis is all
that is needed. An intro video takes you through the main features...
 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."
Thursday the 24th
 Here's a prime example of your government
hard at work: "FCC:
Amateur Service Licensees May Not Use Radio Equipment to Commit Criminal Acts."
That's right, if you are one of those Hams who thought it was OK to use your radio
in the committing of a crime, ignorance of the law is no longer an excuse. At first
I thought this was yet another example of bureaucratic inanity. However, upon further
consideration, this could just be a precursory "shot across the bow" to anyone who
might engage in conversation disapproving of government dictates. If you think that
might be crazy thinking, consider how our neighbors to the north recently arrested
Freedom Convoy organizer
Tamara Lich on charges of "counseling to commit mischief." You have been warned.
 This statement by Bruce Richards is an absolute
truism, especially regarding ultimate system performance: "Transmission
line lead-in is a necessary evil. The service technician should not regard it
lightly. The best antenna and the best receiver in the country may not give satisfactory
reception unless serious attention is paid to the connection between them." Gauging
from some of the reader-submitted questions over the years to QST magazine columnists,
a lot of people do not fully understand and/or appreciate the significant role the
transmission line between the antenna and transmitter/receiver plays. Much more
concern is expressed over loss of power out during transmission, but few seem to
consider how the received signal is impacted due to resistive and/or mismatch losses
in the transmission line. The minimum discernable signal (MDS) is directly affected,
dB for dB, by line loss, so minimizing loss is extremely important when you need
to receive weak signals...
 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.
 "Researchers at Aalto University propose
method of
transducing frequency to power. The world's most commonly used system of measurement,
the International System of Units (SI), was redefined in 2019. Since then, units
have needed to be defined in terms of the constants of Nature - that is, Nature's
rules that are fixed and of no uncertainty, such as the speed of light - and not
in terms of arbitrary references. This has meant that new research for relating
the many units of the system to the constants through experimental realizations
has been called for. 'The redefinition has caused a need for new realizations,'
says Professor Jukka Pekola. Researchers at Aalto University have now found a promising
new way to link the watt (the unit of power) to the constants of Nature. They believe
their method could show the way towards a new power standard, that is, a new way
to produce an a priori known amount of power against which other power sources
and detectors can be compared..."
 This Radio Service Data Sheet is from the
series published by Radio-Craft magazine in the 1920s and 1930s. The "2-Unit"
part of the title indicated, per the schematic, that the power supply and the speaker
output drivers were in a separate chassis that would have been mounted in the trunk
or under a seat. I could not find an example of an actual
RCA Model M-70 auto radio, but the thumbnail image to the left from information
on the RadioMuseum.org website at least gives an idea as to its appearance. I am
posting them for the benefit of people who restore those vintage models to working
order. It is still possible to buy Sam's Photofacts packages that include schematics
and alignment data, but these info sheets fill the gap for ones either not available,
or for someone needing to get a feeling for what he/she is up against before making
a full commitment to the task...
 New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 12,000 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, which keeps the major search engines interested enough to
spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
 Alliance Test Equipment 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.
Alliance Test will purchase your excess test equipment in large or small lots. Blog
posts offer advice on application and use of a wide range of test equipment. Please
visit Allied Test Equipment today to see how they can help your project.
Wednesday the 23rd
 Micarta was a relatively significant synthetic
material when George Westinghouse invented it sometime around 1910. It was a composite
of phenolic resins mixed with structural components like paper, wool, cotton, linen,
and others which would facilitate molding into simple and complex shapes. Although
even the wooden cabinets manufactured at the time were often very curvaceous and
decorative, the process was expensive compared to molding in forms. Micarta has
the advantage of being hard and rigid for good structural integrity, but since the
color permeated the part, scratched and dings did not show as readily. Its high
resistivity made it a good insulator so use in high voltage assemblies and for circuit
boards was common. Look at just about any electronic or electrical product dating
before about 1950 and you will almost surely find Micarta (or a variation of it)
somewhere in or on it...
 "A Honeywell breakthrough in compact satellite
communications technology will bring the safety, connectivity and efficiency trusted
for decades by airplane manufacturers and airlines to three of Pipistrel's new aircraft,
including the fixed-wing Surveyor and both unmanned Nuuva platforms, the V300 and
smaller V20. Weighing in at only 2.2 pounds, Honeywell's
Small UAV SATCOM system is 90% lighter than the company's next smallest connectivity
system, yet it brings the same capabilities enjoyed by larger aircraft to the Nuuva
V300, V20 and Surveyor. This is the first time Honeywell's new system will be implemented
specifically on an unmanned cargo or optionally manned aerial vehicle and is expected
to unlock global beyond-visual-line-of-sight (BVLOS) connectivity..."
 Here are the schematics & parts lists
for the
Hoffman model A301 tabletop radio. It was published in the August 1947 issue
of Radio News magazine. I typically run OCR on them to separate the textual
content and include part of that to help the search engines find it. However, this
one did not have any textual description. There are still many people who restore
and service these vintage radios, and often it can be difficult or impossible to
find schematics and/or tuning information. The thumbnail to the left is a pretty
nice example of a Hoffman model A301 tabletop radio currently listed on eBay. I
keep a running list of all data sheets...
 ConductRF offers many lines of Lab &
Production RF Test solutions for DC to 18 GHz. TEA80 series
TESTeCON and TESTeLINK coaxial cable product lines feature standard connector
choices include straight male, female, and bulkhead, and right angle male. Standard
interfaces include type-N, TNC, SMA, 3.5 mm, and 2.92 mm. Phase stable
testing ±4° to 18 GHz, amplitude stable to ±0.2 dB to 18 GHz, max
power 170 W @ 18 GHz, flex life over 10,000 cycles, cable loss <0.330 dB/ft
@ 18 GHz, VSWR <1.30:1 (typical < 1.20:1). These cables can be purchased
directly from Digi-Key...
 Eastern Amplifier's history is well hidden
on the Web. The best clue I could find regarding their history is from this interview
on Ralph Baer who says Eastern Amplifier Company became Loral. (see p13. The title
of "It's Spring... and the Plants Are Booming!" was a double entendre playing off
the drawing of a mother and her daughter standing in a field, but actually referring
to the industrial war machine cranking out weapons and supplies for our troops "Over
There." It reminds me of an older radio host who would remark that he could remember
"the bees buzzing" as heard from his back yard on Long Island. He was alluding to
the 'B-' series bombers taking off and landing from Mitchel Field near his home.
Note: Amazingly, the grandson of Eastern Amplifier company founder Leonard Meyerson,
Matt Meyerson, saw this page and wrote the following...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
 RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
Tuesday the 22nd
 Here are a few more
electronics-themed comics from a 1940 issue of Radio News magazine.
You can probably tell from the situations that people still considered "wireless,"
aka radio, to be a novel and wonderful - even mysterious - invention. Every type
of situation from utility to obsession to fantasy was part of the experience. Two
of the four comics from this set addresses amateur radio scenarios. Note the predilection
predicted of viewers or the newfangled (at the time) television (or televisor).
Little did the artist know how addictive such contraptions would be - first in the
form of TV, then the form personal computer, and finally in the form of the present
day video delivery medium of smartphones...
 "The first
molecular electronics chip has been developed, realizing a 50-year-old goal
of integrating single molecules into circuits to achieve the ultimate scaling limits
of Moore's Law. Developed by Roswell Biotechnologies and a multi-disciplinary team
of leading academic scientists, the chip uses single molecules as universal sensor
elements in a circuit to create a programmable biosensor with real-time, single-molecule
sensitivity and unlimited scalability in sensor pixel density. This innovation,
appearing this week in a peer-reviewed article in the Proceedings of the National
Academy of Sciences (PNAS), will power advances in diverse fields that are fundamentally
based on observing molecular interactions, including drug discovery, diagnostics,
DNA sequencing, and proteomics. 'Biology works by single molecules talking to each
other, but our existing measurement methods cannot detect this,' said co-author
Jim Tour..."
 Planar Monolithic Industries (PMI), a leading
supplier of custom, high-reliability
MIC/MMIC components and subsystems for applications in space, military, communications,
commercial and consumer electronics systems for more than three decades, recently
introduced five new products in their extensive line of RF and microwave components.
Included are a 1 to 20 GHz successive detection log video amplifier (SDLVA),
an integrated microwave filter assembly covering 2 to 6 GHz, a 10 MHz
to 18 GHz coaxial power limiter, a 12.8 GHz phase locked dielectric resonator
oscillator (PLDRO), and a 4.4 to 7.8 GHz downconverter module...
 "The fact that every part of this ship was
built by the lowest bidder." That, according to Gene Kranz (NASA Flight Director
during the Gemini and Apollo missions), was Alan Shepard's reply when asked what
he thought about as he sat atop the
Mercury Redstone rocket*, waiting for liftoff. Shepard knew the boost vehicle,
the "Redstone," was originally designed as an expendable ballistic missile and not
for safely launching humans into space might have had something to do with it, too.
This 1957 vintage article (5 years prior to Shepard's flight), describes some the
electronics systems that were used in the program both onboard for stabilization
and on the ground for guidance. "A new type computer can solve in five minutes a
ballistic trajectory problem which would require a man more than a year to complete."
Today, a cellphone app can do it in less than a second...
 Engineers'
unions have been around in the U.S. for decades, although not nearly in as large
a percentage as in Europe. EE Times' Cabe Atwell has an interesting piece entitled
"The Pros,
Cons of Unions for Engineers," wherein he presents some ups and downs of unions
for professional groups like airline pilots, teachers, nurses, etc. Although he
makes no specific conclusion on pro vs. con, the conclusion appears to be against
unions because of the unique needs, behaviors, and expectations of American (and
worldwide) engineers. The chief issues are autonomy in decision making and salary
negotiations. It's a good read that will only take a few minutes...
 The term "drone"
these days for most invokes the image of a little plastic spider-looking thing with
propellers mounted at the ends of the arms - usually with a toothless bumpkin at
the controls. Those same people often think drones are relatively new devices. People
with a just a little more information automatically classify all radio control (R/C)
models, be they traditional fixed-wing aircraft or helicopters, as drones. Pilots
of the aforementioned models are even likely, per observers, to have all their teeth
and bathe regularly. I happen to be one of the latter type R/C modelers and while
I no longer possess all 32 teeth I had at birth, I do bathe regularly. Drones have
been around since World War I where they were used for target practice by ground-based
marksmen. Once radio remote control became practical, adopting it for use in pilotless
aerial platforms was a natural evolution. I have written in the past about what
a large contribution hobbyists have made to "drone" technology both through their
technical prowess and flying ability...
RF Cafe's raison d'être is and always has
been to provide useful, quality content for engineers, technicians, engineering
managers, students, and hobbyists. Part of that mission is offering to post applicable
job openings. HR department employees and/or managers of hiring companies are welcome
to submit opportunities for posting at no charge (of course a gratuity will be graciously
accepted). 3rd party recruiters and temp agencies are not included so as to assure
a high quality of listings. Please read through the easy procedure to benefit from
RF Cafe's high quality visitors ...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
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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