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4 of the November 2019 homepage archives. Friday 22
 Just as most people no longer wear a wristwatch
since their (practically) surgically attached smartphones can provide the time,
few people bother with carrying around an electronic calculator. It's' been that
way for at least a decade now. When this article entitled "Calculators Get Smaller, Smarter and Cheaper" appeared in a 1974
issue of Popular Mechanics magazine, pocket electronic calculators were still a
relatively new phenomenon. Hewlett Packard had introduced their first calculator,
the HP-35, just two years earlier. The first American-made pocket calculator, the
Bowmar 910B, aka "The Brain," came out in late 1971/early 1972 and sold for
about $240. It had only basic math functions and sported a tiny LED display.
Prices fell very quickly as many companies were releasing models with more and
more features. By the time of this article, calculators with basic functions
could be bought for a mere $16.95 ($84.05 in 2019 money...
 RF Cafe typically receives
8,000-15,000 website
visits each weekday and about half that on
weekends. RF Cafe is a favorite of engineers, technicians, hobbyists, and
students all over the world. With more than 7,000 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, Facebook,
and Twitter. If you need your company news to be seen, RF Cafe is the place to
be. Banner advertising begins at $175/month...
 Triad RF, located in East Brunswick, NJ, is a
leader in the design and manufacture of RF SSPAs and Systems. An Applications Engineer
is needed to support our customers and provide them with pre-sales technical support
on our products. Tasks include working with customers and recommending suitable
products based on their radio link and system requirements. The applications engineer
will also work with Sales Administrators and assist them in the preparation of customer
quotes. The applications engineer will also work with the test lab in establishing
design test standards based on customer requirements. Skills and qualification include:
Understanding of basic electronics concepts such as NPN transistors, MOSFETS, TTL
logic, supply voltage, current draw, power added efficiency, knowledge of amplifier-related
concepts such as gain, power output, power compression, linearity...
 This is a repeat of something I posted a decade
ago, but by now millions more people have entered the electronics realm and might
appreciate it. You might, too, if you didn't see it originally. You have probably
seen somewhere along the line in your electronics career the resistor cube problem. The 12 edges of the cube each contain
a 1 Ω resistor, and the challenge is to calculate what the equivalent resistance
is between two opposing corners. It is a daunting problem using straight circuit
analysis, since it requires writing and solving multiple mesh equations. There
are lots of opportunities for making mistakes. One option if you had the time
and facilities would be to build the model in a circuit simulator and let it
determine the result. Usually, though, the cube is thrust upon you in a
compromising situation, like in a job interview...
 "The latest International Amateur Radio Union
Region 1 Monitoring System (IARUMS) newsletter reports the
Russian "Contayner" over-the-horizon radar (OTHR) has been active
in the 7, 10, 14, and 18 MHz amateur radio allocations (amateur radio is primary
on 40, 20, and 17 meters). The OTHR transmissions have been 40 sweeps/second, FM
on pulse, and 12 kHz wide. Additionally, IARUMS reports a significant increase
in Russian military traffic using F1B, PSK, and orthogonal frequency division multiplex
(OFDM) on 40, 30, 20, and 15 meters. IARUMS on November 13 reported an OTHR in northern
Iran on 6.078 – 7.022 MHz, AM on pulse, 81 sweeps/second, 44 kHz wide."
 Axiom Test Equipment allows you to
rent or
buy test equipment,
repair
test equipment, or sell or trade test equipment. They are committed to providing
superior customer service and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today!
Thursday 21
 The year was 1941 and the radio industry
was going strong worldwide. Sales of receivers was hitting new highs every quarter
and service shops had all the work they could handle for repair, upgrades, and installations.
The radio broadcast realm was scrambling to build new studios, install transmitters
and antennas, hire announcers and managers, and upgrade to keep up with the quickly
evolving business. Take a look at these 24 full pages of
radio-related products offered by the Sears, Roebuck Company
in their Fall and Winter 1941-1942 catalog. It is typical of most radio
manufacturers' catalogs of the era. For the last decade engineers had been
working overtime to satisfy consumer demand for fancier cabinet designs with
fancier features. So strong was public demand that people put their highest
priority on acquiring the latest models (not unlike the smartphone craze of
today). Then,...
 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 ...
 The
RCA Victor Model C9-4 is a 9-tube, 3-band superheterodyne console
model radio made in the mid 1930s. A Radio Service Data Sheet for it appeared in
the January 1936 issue of Radio-Craft magazine. The image of the radio
was found on the RadioMuseum.org website. FM broadcasting was not in common use
yet, so only AM bands and some shortwave bands were available. In fact, 1936 was
the year that frequency modulation (FM) inventor Edwin H. Armstrong first
demonstrated his newfangled concept that largely solved the electrical static
noise problem cause by lightning, motor brushes, arcing overhead power lines...
 This High Density Switched Reluctance Motor (HDSRM)
designed by Newcastle University's Advanced Electric Machines (AEM) could be a serious
game changer to the electric vehicle industry if it proves viable. The 6-phase motor
does not use permanent magnets or copper conductors, and claims to be competitive
in performance with the current crop of motors that need rare earth magnets and
copper wire. That represents major advantages in lower cost and independence from
rare earth magnets, which now come primarily from China. Be sure to watch the video.
Jolly good show, chaps!
 ThinkRF Corporation, the leader in software-defined
spectrum analysis, today announced the release of the
PyRF3 Development Framework with support for version 3.0 of the
Python Language Application Programming Interface (API). This latest API enables
command, control and data acquisition using ThinkRF Real-Time Spectrum Analyzer
platforms, including the ThinkRF R55x0 and R57x0 analyzers. The updated version
ensures RF application developers can leverage the PyRF Development Framework to
build custom solutions, integrate new capabilities, and develop or extend products
quickly and easily. PyRF is a freely available, comprehensive
development environment for wireless signal analysis, built on the Python
Programming Language...
Res-Net Microwave has a complete line of precision
RF & microwave components including attenuators, terminations,
resistors, and diode detectors for commercial, military, and space applications.
Products range from the small flange type to large 2,000 watt connectorized power
attenuators and/or terminations at frequencies up to 26.5 GHz. In-house photo
etch and laser trim capability. The company is a leader in development and production
of the films required for these type of RF/microwave components. Please check out
Res-Net Microwave's website to see how they can help with your current project.
Wednesday 20
 In 1958, most people were not accustomed
to seeing the now-familiar maps plotting the sinusoidal courses of satellites across
the face of the earth. It had only been in October of the previous year that any
object other than the moon was in orbit around our home planet - that was U.S.S.R.'s
Sputnik. Just as people of all ages and all backgrounds enthusiastically joined
in the newfangled phenomenon of aeroplanes after the Wright Brothers flew their
fragile craft at Kitty Hawk, electronics communications and scientists worldwide
hopped aboard the satellite train (so to speak). This article from a 1958 issue
of Radio & TV News magazine provided insight into the construction
and flight characteristics of
early U.S. satellites, and offered advice on how to
participate in the ongoing International Geophysical Year (IGY) research effort
by tuning in and reporting your signal reception characteristics. Activity was
not just the domain of operators with sophisticated equipment...
 Sam Benzacar of Anatech Electronics, an RF
and microwave filter company, has published his November newsletter that features
his short op-ed entitled "Is 5G Safe for Humans? No One Knows." The controversy over
whether or not RF radiation from wireless devices - cellphones, notebook
computers, tablets, smart meters, et al, is harmful to human body cells has been
with us since the early 1990s, when the Wireless Revolution began. Industry
standards groups have defined Specific Absorption Rate (SAR) levels for exposure
that model human anatomy and cell structure in order to scientifically assess
the effects of RF radiation. As with studies done with other controversial
topics like tobacco and pharmaceuticals, the "truth" is as much subjective as it
is objective, and the two side of the argument will never agree...
 This quiz from Popular Electronics
magazine challenges (not too much, though) your knowledge of
energy conversion in common devices. A few of them might be
unfamiliar to people born after about 1990, but even so, you've probably seem
them all at some point, especially if you are a regular RF Cafe visitor (meaning
you're probably smart). It won't be giving anything away by telling you that
item B is a heater that screws into a light bulb socket, and item F is a
phonograph stylus Robert P. Balin constructed many quizzes of this kind in the
1960s and 70s. A complete list of all the Popular Electronics Quizzes is lower
on this page...
 Axiom Test Equipment, an electronic test equipment
rentals and sales company headquartered in San Diego, has published a blog post
entitled "Turn on the Temperature with Thermal Test Systems," explaining
the need to properly evaluate product function across the full range of expected
ambient temperature conditions. Doing so helps guarantee favorable customer
experiences and online ratings, as well as reduces costs of warranty service. It
begins: "Electronic device performance is sensitive to temperature, with most
electronic devices and components specified according to operating and storage
temperature ranges. Those ranges differ according to the type of component and
application, with electronic products for industrial and military applications
usually..."
 "Electromagnetic interference (EMI) can plague
bus bars just like it does with cables. Here are the answers to
some common questions. Do bus bars need EMI filters? Yes, they do. Just because
they're large imposing structures, they can cause interference in other systems
if you don't measure the EMI and take steps to get it under legal limits. In some
cases, you might want to reduce EMI even further than the legal requirement to make
a quiet electrical environment for your sensors or control system. EMI noise is
created by any fast-changing currents, often represented by the calculus term di/dt,
that is, the change of current over time. Fast-changing currents have high di/dt.
If those currents ..."
Since 1961, MECA Electronics has designed and manufactured an extensive line
of RF & microwave components for in-building, satellite, radar,
radio, telemetry, mobile radio, aviation & ATC. Attenuators, directional &
hybrid couplers, isolators & circulators, power dividers & combiners, loads,
DC blocks, bias-Ts and adapters & cables. MECA has long been the 'backbone'
of high performance wired and air-interfaced networks such as in-building applications,
satellite communications, radar, radio communications, telemetry applications, mobile
radio, aviation & air traffic communications.
Tuesday 19
 Proving once again what a visionary Hugo
Gernsback was regarding science and engineering, he published in his Radio-Craft
magazine this prognostication for the eventual supplanting of point-to-point wiring
with
printed circuit boards. Admittedly, by 1948 the electronics
industry had begun to outgrow hand-wired chassis assemblies with a rats nest of
wires, components, and terminal strips. It was in dire need of a new paradigm
that reduced labor costs and reduced the opportunity for wiring errors. Less
than a year earlier (December 1947) the trio of engineers at Bell Labs announced
their transistor invention, so Mr. Gernsback knew the world was about to change
significantly. Bulky transformers, vacuum tubes, and high voltage circuits would
soon be relegated - at least in the consumer product realm - to the newfangled
television products, so miniaturization would follow quickly. Even the smaller
fingers of women on the assembly lines...
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 ...
 Skyworks is pleased introduce the SKY66318-11,
a new addition to our family of high-efficiency power amplifiers (PA) that are designed
for the stringent requirements of enterprise small cell applications. The PA offers
wide instantaneous bandwidth (100 MHz) and is fully input/output matched with
high gain and efficiency. On-chip active biasing circuitry is also integrated to
compensate for PA performance over temperature, voltage, and process variations.
The device comes in a compact 5 x 5 mm package, operates from a single 5 V
power supply, and is ideal for 4G LTE and 5G NR systems from 3300 to 3600 MHz.
The SKY66318-11 is also part of major transceiver reference designs ...
 Here is a little electronics hobbyist humor
in the form of a comic series titled "Hobnobbing with Harbaugh," compliments of
Popular Electronics artist Dave Harbaugh. Citizens Band radio and dirty
hippies were the topic of the day in the 1970s, so that's what you see in a
couple of these comics. I got my first 23-channel CB radio (FCC mandated 40
channels in 1977) in 1976 and installed it in my 1969 Camaro SS hot rod. It
required a Class D radio operator license at the time, but shortly thereafter no
license was needed. The "Inventions Wanted" comic is my favorite, followed by
"Mayday... Mayday!" You don't need to be an amateur radio operator to appreciate
these comic strips...
 "Satellites do a lot of things - they help
people navigate from one place to another, they deliver television programming,
they search for new stars and exo-planets and they enable the U.S. nuclear deterrence
strategy. But until recently, one thing they haven't done - or needed to do - is
defend themselves. That may soon change. Researchers at Sandia National Laboratories
launched a seven-year mission campaign this month to develop the science, technology
and architecture needed for autonomous
satellite protection systems. The campaign, called STARCS (Science
and Technology Advancing Resilience for Contested Space), will fund dozens of Laboratory
Directed Research and Development projects that focus on three critical areas ..."
 ConductRF is continually innovating and developing
new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test Cables for labs. ConductRF makes production and
test coax cable assemblies for amplitude and phased matched VNA applications as
well as standard & precision RF connectors. Over 1,000 solutions for low PIM
in-building to choose from in the iBwave component library. They also provide custom
coax solutions for applications where some standard just won't do. A partnership
with Newark assures fast, reliable access. Please visit
ConductRF today to see how they can help your project!
Monday 18
 Forgive me if I sound like a broken record
(a scratched record, actually), but when selecting articles for posting here on
RF Cafe, I like to include ones that are directed toward newcomers to the field
of electronics as well as for seasoned veterans. This piece from a 1958 issue
of Radio & TV News magazine entitled "Basic Electronic Counting," is a prime example in that it introduces
the concept of binary numbers. We've all been there at some point in our careers.
A big difference between now and when this article appeared is that in 1958, almost
nobody was familiar to binary numbers, and fuggetabout [sic] octal and hexadecimal.
Only those relatively few people designing and working with multimillion dollar,
vacuum tube-based digital computers installed in universities, megacorporations,
and government research facilities...
 "The
2020 Cubesat Developers Workshop will be held May 4 - 6 at the
Cal Poly Performing Arts Center in San Luis Obispo, California. The planning team
has announced a call for abstracts. All abstract and poster applications should
be submitted using the online submission form on the conference website by Friday,
January 10, 2020."
 Exodus Advanced Communications' model
AMP2070C power amplifier designed for broadband EMI/RFI, lab,
communications and EW applications. Class A/AB linear design for all modulations
and industry standards. Covers 700 MHz - 6.0 GHz, produces 100 W minimum, 50 W
P1dB, 50 dB gain. Excellent gain flatness, optional monitoring parameters for
forward / reflected power, voltage, current and temperature sensing for superb
reliability and ruggedness. Suitable for CW, pulse and all single channel
modulation standards Built-in protection circuits...
 Radio Service Data Sheets were published
by various electronics trade magazines back in the early to middle decades of the
last century. SAMS Photofact document sets were published on just about every appliance
made, and those had much more detail than these briefs. However, for the low-budget
repair shop or the do-it-yourselfer, the Radio Service Data Sheets were a godsend.
I have been scanning, cleaning up, and posting all the ones I find in my vintage
electronics magazine collection. See a complete list at the bottom. Many fine examples
of restored vintage radios can be found on the Internet. A restored example of the
RCA Victor Model 102 s appears on the RadioMuseum.com
website...
 "Circuits made from thread are combined with
thread-based sensors to create flexible devices. A transistor
has been made from linen thread, enabling the creation of electronic devices made
entirely of thin threads that could be woven into fabric, worn on the skin, or implanted
surgically for diagnostic monitoring. The flexible electronic devices could enable
a range of applications that conform to different shapes and allow free movement
without compromising function. The thread-based transistors (TBTs) can be made into
all-thread-based logic circuits and integrated circuits. The circuits replace the
last remaining rigid component of many current flexible devices and when combined
with thread-based sensors, enable the creation of completely flexible ..."
 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.
 Copper Mountain Technologies
develops innovative and robust RF test and measurement solutions for engineers all
over the world. Copper Mountain's extensive line of unique form factor
Vector
Network Analyzers include an RF measurement module and a software application
which runs on any Windows PC, laptop or tablet, connecting to the measurement hardware
via USB interface. The result is a lower cost, faster, more effective test process
that fits into the modern workspace in lab, production, field and secure testing
environments.
Sunday 17
 For two decades, I have been creating custom
engineering- and science-themed crossword puzzles for the brain-exercising
benefit and pleasure of RF Cafe visitors who are fellow cruciverbalists. This November
17, 2019, puzzle uses a database of thousands of words which I have 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 star like
Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons
which...
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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