Sunday the 7th
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
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
"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,
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
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
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
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
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
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
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..."
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
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.