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4 of the March 2021 homepage
archives. Sunday the 7th
 This
RF Engineering Crossword Puzzle for March 7th has many words and
clues related to... you guessed it... RF engineering - and mathematics, chemistry,
physics, and other technical words. 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.,
Hedy Lamarr or the Bikini Atoll). The technically inclined cruciverbalists amongst
us will appreciate the effort. Enjoy!
Friday the 5th
 Not many people rewind transformers these
days, but then even in 1955 when this "Design Tips for Rewinding Your Own Transformers" article appeared
in Radio News magazine not many were rewinding transformers. Plenty of
radio repair servicemen did, though, because replacements were expensive and getting
replacements for other than common transformers could take a long time. There was
no searching for one on the Internet and having it delivered in a couple days. Since
many - if not most, by necessity - electronics repair shops kept subscriptions to
available trade magazines, publishing an article like this provided a great service.
Author James Dolan provides all the necessary information for either designing your
own transformer from scratch or for modifying an existing transformer to meet your
specific requirements...
 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.
 "Research could lead to the development
of new materials with large
magnetoelectric (ME) coupling for next-generation multifunctional
devices, including, multi-state (neuromorphic-like) circuits and memories, and E-field
tunable microwave resonators for secure communications. Multifunctional magnetoelectric
materials with high exchange represent a missing 'holy grail' of materials physics.
To combine polarization and magnetization in the same solid is nothing short of
actually controlling the fundamental nature of electromagnetism in matter. Although
magneto-electricity (ME) is an intrinsic phenomenon in some natural materials at
low temperature, such single-phase materials suffer from an extremely weak ME exchange..."
 You can go to just about any store these
days and buy a tube of RTV (room temperature vulcanizing) rubber caulk. That was not the case
as recently as the 1960s and 1970s. Here is a short news item about how Dow Corning
Corporation's breakthrough new compound was set to revolutionize hermetic sealing
of critical electronic assemblies. It shows entire subassemblies of connectors,
wires, and discrete components (no ICs at the time) completely encapsulated in the
stuff. I remember at Westinghouse Electric, where I worked as a technician after
a tour in the USAF, we used RTV for sealing bulkhead-mounted connectors on torpedo
heads and towed sonar arrays. We also used massive quantities of it to seal off
machined metal molds for ceramic transducer element arrays prior to potting them
with a polyurethane compound. That was cool work. The heavy aluminum molds, about
6-feet long, were placed in a huge, thick-walled aluminum tube and a vacuum...
 Many
of us are familiar with
the
math behind the Smith chart. Some have written spreadsheets and software for
creating Smith charts, if only for the satisfaction of being able to do so. It really
is quite simple (complex, actually - get it?) to do, but as with most things a genius
mind (i.e., Phillip
Smith) was needed to think of doing it in the first place. John Dunn, a very
smart guy in his own right, posted a good primer on the subject on the EDN
website. If you are new to the Smith chart or just want to do a refresh, then surf
on over to read his article, and maybe click on the three related links at the bottom
for more info.
 Centric RF is a company offering from stock
various RF and
Microwave coaxial components, including attenuators, adapters, cable assemblies,
terminations, power dividers, and more. We believe in offering high performance
parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power
levels from 0.5-500 watts are available off the shelf. Order today, ship today!
Centric RF is currently looking for vendors to partner with them. Please visit Centric
RF today.
Thursday the 4th
 Here for your enjoyment are a few more
tech-themed comics from a vintage Radio-Electronics magazine.
Television antenna installations and stereophonic audio systems were a big deal
back in the day, so lots of comics were centered on the themes. Everything was new
and mystical, and ownership of a top-end TV or stereo was a real sign of influence
and/or savvy. The comic from page 96 is actually an advertisement for Jensen phonograph
needles, which of course were key components to the aforementioned stereo systems.
Lost on Millennials (not their fault) and later is probably the allusion to how
the bedraggled couple needing to resort to a Flintstones-style (also likely unfamiliar
to Millennials) record player...
 According to this
engineering salary report for 2020, pay continued on an upward
trend in the U.S. despite the Wuhan Flu debacle. Data collected by technology career
company Dice indicated the average salary (not including benefits, bonuses,
etc.) of a tech professional in the U.S. increased 3.6% to $97,859 in 2020. Dice
based its numbers on a survey of about 9,000 tech employees - which does not really
seem to me like a very significant sample size. Looking at the bar chart, most areas
reported an increase in salaries, with on the extreme Northwest cities of Seattle
and Portland losing ground. The Silicon Valley area went from $123,826 to $126,801,
a meager 2.4% increase when living in a land where software developers domicile
in their cars due to the cost of housing. Only augmented and virtual reality (AR
and VR) software engineers saw a significant increase (13%).
 "Using laser beams to create excited Rydberg
atoms, Army researchers say they built a
quantum sensor to detect the complete radio frequency spectrum.
The findings, published in the Physical Review Applied, show the Rydberg
sensor can pick up Bluetooth, Wi-Fi, AM and FM radio, and other communications signals
on frequencies as high as 20 GHz. Although more engineering and physics work
is necessary, the device has the potential to unleash new potentials for military
communications, spectrum awareness, and quantum electronic warfare (EW). Using the
lasers, rubidium atoms are excited into desired Rydberg states, allowing researchers
to measure atoms' response to an electric field and hone in on a portion of the
spectrum they wanted to measure. Because Rydberg atoms are extremely sensitive to
the circuit's electric fields..."
 Oddly, the article does not tell you the
origin of the acronym "WAVES." From the U.S. Navy's history page: "After a twenty-three-year
absence, women returned to general Navy service in early August 1942, when Mildred
McAfee was sworn in as a Naval Reserve Lieutenant Commander, the first female commissioned
officer in U.S. Navy history, and the first Director of the WAVES, or "Women Accepted
for Volunteer Emergency Service". In the decades since the last of the Yeomen (F)
left active duty, only a relatively small corps of Navy Nurses represented their
gender in the Naval service, and they had never had formal officer status. Now,
the Navy was preparing to accept not just a large number of enlisted women, as it
had done during World War I, but female Commissioned Officers to supervise them.
It was a development of lasting significance, notwithstanding the WAVES' name, which
indicated...
Make Sure That Electric
Car Does Not Run out of Juice
 Axiom Test Equipment, an electronic test
equipment rental and sales company, has published a new blog post entitled, "Make Sure That Electric Car Does Not Run out of Juice," that informs
people who are looking to monitor the battery and charging system of their electric
vehicle (EV), hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle
(PHEV). Learn how you can maintain a healthy and high performing battery through
our informative guide. In order to ensure that your EV is driving smoothly, you
must do careful maintenance of the battery and powertrains. Two of the most significant
tests includes an internal resistance test and a battery capacity / discharge test.
Doing these tests with the proper equipment will allow you to see if your EV can
handle short circuits, over-voltage conditions, and over charging...
 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!
Wednesday the 3rd
 About the only kind of transmission line
homeowners use today is 75 Ω coaxial cable for television and Internet connections.
Up until the turn of this new century (two decades old by now - ugh!), a fair percentage
of TV owners still had an antenna mounted on the roof or maybe rabbit ears sitting
atop the set.
Twin lead transmission line was still a common sight as at least
the "last mile" (last few inches, actually) connection via an impedance converter
to the pair of screws on the back of a TV or FM radio. By then, most TVs also had
an "F" coaxial connector for direct attachment without a converter. Internet connections
at the time were telephone cords connected to the modem board inside your computer.
It's hard to believe that was just a relatively few years ago that we early WWW
users got to cross our fingers when dialing up a local phone number for AOL, Earthlink,
Compuserve, Prodigy, Mindspring...
 "Even in the world of the smallest particles
with their own special rules, things
cannot
proceed infinitely fast. Physicists at the University of Bonn have now shown
what the speed limit is for complex quantum operations. The study also involved
scientists from MIT, the universities of Hamburg, Cologne and Padua, and the Jülich
Research Center. The results are important for the realization of quantum computers,
among other things. They are published in the prestigious journal Physical Review
X, and covered by the Physics Magazine of the American Physical Society. Suppose
you observe a waiter (the lockdown is already history) who on New Year's Eve has
to serve an entire tray of champagne glasses just a few minutes before midnight.
He rushes from guest to guest at top speed..."
 Safe-Com Wireless designs and manufactures wireless
communications equipment for first responders. The equipment comprises boosters
and fiber optic distributed antenna systems. The equipment is used inside buildings
to permit the first responder to communicate during emergence incidents. The Radio
Frequency Test Technician / Associate Engineer position requires minimum 5 - 15
years direct experience in RF board level testing using a spectrum analyzer, radio
frequency signal generators and similar radio frequency equipment. The successful
candidate will be experienced in reading circuit schematics, troubleshooting circuits
and documenting test results. Also hand soldering and modification of surface and
through-hole printed circuit boards (PCBs) is required. Direct experience in a production
work environment required...
 RCA's Numitron was their answer to the Nixie
tube (manufactured by Burroughs Corporation). It was a simpler 7-segment incandescent
display (DR2010) that, with all lines energized, formed the number 8. It worked
off of +3.5 to +5 volts, with each element requiring 24 mA of current. The
number 8 drew 192 mA of current and dissipated 0.672 W at 3.5 volts and
a whopping 0.96 W at 5 volts! RCA marketed a BCD*-to-7-segment display driver
(the CD2501E). The
Numitron was pitched as a sensible alternative to the 7-segment
LED display, but with an element size of 0.35" wide by 0.6" high, there was no real
advantage over the LEDs, which were just entering the electronics market in 1970.
Numitrons do have a certain nostalgic 'cool' factor, though. It is interesting to
note that the author's last name, Wood, is the same as that of Frank Wood, who was
issued...
 Teledyne e2v HiRel Electronics, a leading
provider of high reliability semiconductor solutions, today announced a new high
reliability partnership with California-based Integra Technologies, Inc. (Integra).
Under the new agreement, Teledyne will leverage Integra's portfolio of
GaN on SiC RF power transistor products to deliver optimized power
solutions for the space market. With Integra, Teledyne e2v HiRel will specialize
in providing high power RF devices for emerging space applications in the LEO and
GEO payload market. Teledyne will also offer high reliability options for Integra's
popular GaN on SiC power devices and pallets targeted at the defense market. "Our
space customers are requesting RF power devices at higher power density levels and
operating at higher frequencies," said Brad Little, VP and General Manager of Teledyne
e2v HiRel. "The combination of our expertise in providing space...
 NextPCB is one of the most experienced PCB
manufacturers in China, has specialized in the PCB and assembly industry for over
15 years. NextPCB provides the most innovative printed circuit boards and assembly
technologies in the highest quality standards, turnaround time as fast as 24 hours,
the lowest manufacturer direct prices, and the most dedicated customer service in
the industry. Turnkey service without a broker including components sourcing, PCB
prototyping, manufacturing, assembly, quality testing, and final shipment. Certified
by IATF16949, ISO9001, ISO14001, UL, CQC, RoHS and REACH.
Tuesday the 2nd
 "The more things change, the more they remain
the same." That old saw has held true throughout the ages, but there seems to be
cycles within cycles that causes, to mix in a metaphor, the pendulum to swing back
and forth in greater and lesser peak amplitudes, and over long periods of time a
bias sets in that causes a perceivable change from the symmetric tick-tock-tick-tock-tick-tock,
to tick----tock-tick----tock-tick----tock-tick. Without an outside-of-the-system
input, the bias grows. If you have a "real" gravity-driven pendulum clock, you probably
know what I mean. Bringing the system back to symmetry requires adjusting the clockworks
movement or "righting" the physical orientation by rotating the clock on the wall
or shimming up one side on the shelf until the preferred tick-tock-tick-tock is
restored. Economic cycles are much the same, as alluded to in this World War II,
War Bonds promotion. There are long periods of overall ups and
overall downs, and in-between there are lesser rises and falls. Eventually, those
who learn to control the cycles tend to insert a bias into the works...
 "Researchers have, for the first time ever,
demonstrated electrical control of
valley transport in 3-D dual-gate diamond field-effect transistors.
Not many people are aware of it, but the diamond is actually a wide-bandgap semiconductor
with many extremely good properties, such as high thermal conductivity, high breakdown
field, high carrier mobilities, and chemical inertness. These properties, together
with the possibility to synthesize high-purity, single-crystalline diamond make
it a very interesting material and a candidate for use4 in power electronics. The
low impurity concentration achieved when fabricating diamond, together with its
rigid lattice, causes it to exhibit a uniquely low scattering rate, especially at
low temperatures..."
 The
Underwriter's Laboratory (UL) is an entity that seems to have
been around forever. A lot of people - maybe most people - assume that it is a government
entity. In fact, it is a non-profit organization sponsored by the National Board
of Fire Underwriters (later changed to American Insurance Association, then to APCIA).
Its roots are traceable back to the Chicago World's Fair in 1893. Concern over the
potential fire hazard of Edison's light bulbs was the impetus for the effort. Another
aspect of the UL that a lot of people don't know is that the UL label of approval
is no guarantee that the device works properly, only that is passes standards of
safety as it relates to fire hazards. This article in the August 1955 edition of
Popular Electronics magazine gives a brief history.
 RF Cafe visitor Tommy Reed sent me this link
to a blog he recently posted on FromDCtoDaylight.com (great name) website entitled,
"17 Best RTL-SDR Software Defined Radio Dongles." About six months
ago I bought the Nooelec NESDR Smart v4 bundle to use with a modification I'm making
to a couple vintage 72/75 MHz radio control systems. The 3rd-party interface
and processing software is OK, but could be better. Otherwise, it works quite well.
Says Tommy: "Software Defined Radios (SDRs) are become more and more popular. This
is partially due to the wide availability of low cost USB dongle SDR radios based
on RTL2832U demodulator chipset. This is where the 'RTL' in RTL-SDR comes from.
While these low cost SDRs are not as capable as some of the higher performance SDR
radios, they do offer a good bang for the buck. In this post we'll take a look at
17 great RTL-SDR dongles..."
 Modelithics is honored to announce that it
has crossed another milestone in the history of the company. As of March 1, 2021
Modelithics,, will be celebrating 20 years of establishment. What
began as a small spinout startup from the University of South Florida has risen
to stand tall as the industry leader in RF, microwave and millimeter-wave measurements
and measurement-based modeling of RF and microwave components and semiconductor
devices. We are proud of our company's many innovative products, custom service
projects, designer focused application notes and other accomplishments that have
proven to be exceptionally productive for our customers...
 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.
Monday the 1st
 With most solid state devices, be they discrete
elements or integrated circuits, discerning their functions by visual inspection
is nearly always impossible. A trained observer can use a microscope on a bare die
to get a good idea of what the various parts do. Memory banks, transistors, resistors,
capacitors, etc., are usually pretty obvious even to someone relatively new at the
job. Opaque overmolded packages and/or extremely small features complicate the task.
In the
vacuum tube days, anyone accustomed to working with them could
fairly easily look at the the arrangement of heaters, cathodes, grids, and plates
- sometimes singular but often multiple - and figure out the function. Experts could
even make a fair guess at the key electrical specifications. Of course that only
applied to those with clear glass envelopes. Tubes with special shapes might have
been a bit more difficult to guess the application. To wit, the long, skinny R-1110
"Pirani Tube" shown here is an example. It is designed to measure ambient pressure...
 LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
 "The Perseverance rover's
Mars Helicopter (Ingenuity) will take off, navigate, and land
on Mars without human intervention. Tucked under the belly of the Perseverance rover
that will be landing on Mars in just a few days is a little helicopter called Ingenuity.
Its body is the size of a box of tissues, slung underneath a pair of 1.2m carbon
fiber rotors on top of four spindly legs. It weighs just 1.8kg, but the importance
of its mission is massive. If everything goes according to plan, Ingenuity will
become the first aircraft to fly on Mars. In order for this to work, Ingenuity has
to survive frigid temperatures, manage merciless power constraints, and attempt
a series of 90 second flights while separated from Earth by 10 light minutes. Which
means that real-time communication..."
 It had been only a little over a decade since
the transistor was invented when this article appeared in the August 1959 edition
of Popular Electronics. Transistors were still a mystery to most people,
including engineers, technicians, and hobbyists. Author James Butterfield takes
a unique approach in presenting the material by writing it as a dialog between an
instructor and a student. If you are also
new to transistors, this will be worth your while to read. The
basics will never change. As an aside (and mentioned in the article), while still
a technician I had a manager one time who actually told an engineer working for
him that a transistor could be made by soldering two diodes together and using the
center node as the base connection...
 KR Electronics, a designer and manufacturer of
high quality filters for the commercial and military markets for more than 45 years,
introduces the model 3450 lumped element bandpass filter with a 1,000 MHz center
frequency and a 1 dB bandwidth of 50 MHz (~975 - 1025 MHz). The filter
is a highly selective elliptic type filter. The filter is supplied either with SMA
connectors (0.60" x 0.60" x 2.25" not including connectors) or in a surface mount
package. Other frequencies and bandwidths are available...
 Atenlab has been operating in Taiwan for
more than a decade, and has sold and installed hundreds chambers around the world.
Holistic, affordable Over-the-Air
(OTA) measurement systems perform comprehensive measurement and test in a controlled
environment. Compact Antenna Test Range (CATR) with one-touch operation supports
multiple systems - 2G, 3G, 4G, 5G - and major instrument brands. [M]ulti-probe OTA
measurement systems offer reduced time measurements over single-probe systems.
These archive pages are provided in order to make it easier for you to find items
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way to find anything on the website is to use the "Search
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