See Page 1 |
2 |
3 |
4 |
5 | of the March 2020 homepage archives. Friday 3
 Comics in modern magazines are a rather
rare phenomenon for some reason, but they were fairly regular features up until
a couple decades ago. This set of
comics from the July 1963 edition of Popular Electronics deals with
high fidelity (Hi-Fi) stereo equipment, which was considered somewhat exotic and
high-end for many people's budgets in the day. Inexplicably (not), that is about
the time that increases in hearing losses among younger people were first being
noticed in audiograms.
 Skyworks Solutions is empowering the wireless
networking revolution. Skyworks is pleased to launch the
SKY66404-11, a 2.4 GHz front-end module (FEM) designed for Zigbee®, Thread,
and Bluetooth® (including Low Energy) ultra-low power IoT applications spanning
sensors, beacons, smart meters and thermostats, wireless cameras, smoke and CO detectors,
and wearables including medical devices. Featuring high-performance in a compact
form factor, SKY66404-11 provides increased efficiency, and more than 4X range extension
over previous models. The integrated module includes a power amplifier, low-noise
amplifier, low-loss bypass path, transmit and receive switches, and digital controls
compatible with 1.7 to 3.6 V CMOS levels...
 $5,000 in 1956 currency is equivalent to
about $46,000 in 2020, per the U.S. Bureau of Labor Statistics' "Inflation Calculator."
That is the value of the amateur radio equipment used by
Mrs. Mary Burke in her work handling "an average of 3000 messages per month,
principally for service personnel overseas." For her tireless wireless efforts,
she was the first woman to win the coveted Edison Award Cup (sponsored by General
Electric). Most of Mrs. Burke's communications was via Morse code, where she restrained
herself to "about 30 words a minute to maintain accuracy". Way to go, Mary!
 "Researchers at the University of California
San Diego developed a wearable technology that can
hide its wearer from heat-detecting sensors such as night vision goggles, even
when the ambient temperature changes. It's a feat that current state of the art
technology cannot match. The new technology can adapt to temperature changes in
just a few minutes, while keeping the wearer comfortable. The device, which is at
the proof-of-concept stage, has a surface that quickly cools down or heats up to
match ambient temperatures, camouflaging the wearer's body heat. The surface can
go from 10 to 38°C in less than a minute. Meanwhile, the inside remains at the same
temperature as human skin, making it comfortable for the wearer. The wireless device..."
 Electronic Design's 2019 Salary & Career
Survey asked readers, among other topics, what their attitudes were regarding
continuing education. The main question in that sections was, "What are some
of the ways in which you continue your engineering education?" I could not find
the total number of respondents to the survey, but of those who did, 87% held a
Bachelor's degree or higher. Among resources used to maintain currency in their
professions, 60% say they use printed engineering & technology publications
while 57% use similar websites. 60% use seminars and webcasts and 65% read whitepapers.
13% attend in-classroom instruction while 31% use online courses. About 45% of employers
reimburse costs for seminars and trade shows, 32% pay for college courses, and 23%
cover nothing at all. Click the link above for the full report, as well as to access
the
Job Satisfaction section from last week.
 TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms are
available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
Thursday 2
 This installment of the multi-month series
of articles on antenna principles covers
directional arrays for 300 MHz and higher. Keep in mind that in 1947 when
this appeared in Radio-Craft magazine, wavelengths of a meter or less were
considered to be at the upper end of the operational range. Parabolic reflector
antennas were the domain primarily of ground-based installations due to the physical
size and weight being prohibitive in airborne platforms, and even then they were
rarely used at the time. Most ground and airborne installations were composed of
dipole antennas with various configurations of reflector and director elements for
desired gain and directivity characteristics. Special applications like for direction
finding and longer wavelength radio communications used loop and long wire antennas,
respectively. Highly directive dipole...
 Withwave offers
ANSYS HFSS 3D EM(Electromagnetic) Simulation Model of board connectors and panel
type connectors for customer design. These 3D models allows RF designers and engineers
to simulate the RF performance of these connectors which is launched on various
types of high frequency PCB. They can reduce time to assemble the connectors and
verify the performance prior to placing an order. we hope to make a commitment to
give customers better testing & Simulation environment. Design Assistance for
ANSYS HFSS Models (version 17.0 or newer) for 3D EM Simulation and 3D Model for
Mechanical Layout (STEP file)...
 Echo 1 launched in August of 1960, finally
allowing America to participate in the Space Race, which until then was roundly
being won by the USSR. Electronics magazines of the day were filled with prognostications
of the future of
space communications. Electronics World dedicated most of their November issue
to satellite Earth stations and advancements being made in ultra sensitive receivers
and powerful transmitters. Since the earliest satellites were literally metallic
balls for reflecting radio signals, it was necessary to optimize both ends of the
communications path since there were no circuits onboard the satellite to perform
signal processing and re-transmission. Bell Labs, of course, was at the forefront
of the technology. In fact a famously serendipitous discovery was made by a couple
scientists in 1964 using the very antenna featured in this advertisement...
 Manufacturing
of all our products continues to operate at full capacity as part of the "Essential
Business" community. Professional high frequency TSA89 series of RF
test cables with performance to 40 GHz. Connector choices include; SMA, Type-N,
3.5mm, 2.92mm, & 2.4mm. Key features: High-frequency point to point cable, light
weight rugged flexible cable, low loss <0.68 dB/ft @ 40 GHz, low VSWR <
1.35:1 (Typical < 1.25:1), RF leakage >-100 dB to 18 GHz, temperature
rated from -55ºC to 125ºC. Cables are in stock and available immediately from Digi-Key.
Here is an interview with ConductRF founder
Dean Gammell.
 "Transistors in computer chips work electrically,
but data can be transmitted more quickly with light. Researchers have therefore
been looking for a way to integrate a laser directly into silicon chips for a long
time. A team of physicists at the Centre de Nanosciences et de Nanotechnologies
(C2N), in collaboration with researchers at Germany's Forschungszentrum Jülich (FZJ)
and STMicroelectronics, have implemented a new material engineering method to fabricate
a laser microdisk in a
strained germanium-tin (GeSn) alloy. They have demonstrated the laser device
with a group IV compound, compatible with Silicon, operating with ultra-low threshold
and under continuous-wave excitation. Optical data transmission enables significantly
higher data rates and ranges than conventional electronic processes, while using
less energy. In data centers, optical cables of a length of around 1 meter are therefore
standard..."
 Wakeup call to everyone: By Ana Swanson in
the March 11, 2020 edition of
The New York Times newspaper, "While the United States remains a global leader
in drug discovery, much of the manufacturing has moved offshore. The last American
plant to make key ingredients for penicillin announced it would close its doors
in 2004. Chinese pharmaceutical companies have supplied more than 90% of U.S. antibiotics,
vitamin C, ibuprofen and hydrocortisone, as well as 70% of acetaminophen and 40
to 45% of heparin in recent years, according to Yanzhong Huang, a senior fellow
for global health at the Council on Foreign Relations..."
 Custom MMIC is a
fabless RF and microwave MMIC
designer entrusted by government and defense industry OEMs. Custom and off-the-shelf
products include switches, phase shifters, attenuators, mixers and multipliers,
and low noise, low phase noise, and distributed amplifiers. From next-generation
long range military radar systems, to advanced aerospace and space-qualified satellite
communications, microwave signal chains are being pushed to new limits - and no
one understands this more than Custom MMIC. Please contact Custom MMIC today to
see how they use their modern engineering, testing and packaging facility to help
your project.
Wednesday 1
 Probably the first exposure most of us have
had to an
electrocardiogram (ECG) is from a television show or a movie. Earlier instances
appeared in hospital settings in a patient's room or in the operating room. Around
the time this installment of "Mac's Service Shop" appeared in Popular Electronics
magazine (1974), the TV show "Emergency" introduced my generation to the field-portable
ECG machine as deployed by Emergency Medical Technician (EMT) responders Johnny
Gage and Roy DeSoto. I remember some of the first episodes had the emergency room
doctors lamenting not having equipment available on the scene that could wirelessly
send critical heart status parameters along with the standard fare of the victim's
"vital signs." Then, one day a portable ECG unit was finally available, ostensibly
revolutionizing the profession...
 Keysight Technologies, a leading technology
company that helps enterprises, service providers and governments accelerate innovation
to connect and secure the world, has launched the
Innovate Anywhere program in response to COVID-19, spanning three key areas:
90-day software trials, remote learning, and scalable live network testing. "At
Keysight, we are committed to helping customers maintain their engineering productivity
no matter where they are working," stated Marie Hattar, CMO at Keysight. "We recognize
COVID-19 is causing drastic changes across the globe, in our communities, our homes,
and our workplaces. We want to help provide a sense of normalcy and enable customers
to do what they do best: to innovate, from anywhere..."
 "Honeywell says that it will release the
world's most powerful
commercial quantum computer by mid-2020. The U.S.-based manufacturer of scientific
and commercial equipment says that the device is based on trapped ions, which is
a different technology than that being pursued by most other commercial developers
including Google and IBM. Honeywell researchers have published details of a smaller
version of the machine that has a 'quantum volume' of 16 and say that it should
be straightforward to scale this up to 64. The fundamental requirement for quantum
computation is a set of quantum bits (qubits) that can interact to form quantum
logic gates that process quantum information. In principle, quantum computers can
perform certain computational task much faster than conventional computers. However,
qubits tend to be very fragile so creating practical quantum computers is a significant
scientific and technological challenge..."
 Z-Communications' new CRO6750X2-LF utilizes
a doubled CRO oscillator design to cover the frequency range of
6750-6750 MHz within a tuning window of 0.5-4.5 Vdc. This new ceramic resonator
VCO features phase noise of -101 dBc/Hz @ 10 kHz offset and is available in Z-COMM's
standard MINI-16-SM package measuring 0.5 in. x 0.5 in. x 0.22 in. The CRO6750X2-LF
is well suited for radar systems requiring optimal spectral purity. This unmatched
VCO is configured to deliver output power of 0±3 dBm into a 50 ohms load and covers
the operating frequency with a low Kvco figure of 5 MHz/V all while operating over
the industrial temperature range of -40 to 85°C. It is specified to run off a 5.0
Vdc supply while drawing only 30 mA of current. The CRO6750X2-LF suppresses both
the ½ and 2nd harmonic to better than -20dBc while limiting pulling...
 Raise your hand if you have ever owned a
CB (Citizens Band) radio. Waaaaay back before everyone carried a cellphone (pre-late-1990s),
the most common form of
unlicensed communication was CB radio. Actually, up through the mid 1970s you
were supposed to purchase a license from the FCC, although no test was required
as it was for amateur radio. My first CB was a 23 channel job that I installed in
my 1969 Chevy Camaro SS, during my senior year in Southern Senior High School.
It was right in the middle of big CB radio craze with CW McCall's "Convoy" song
topping the U.S. Billboard charts. My self-appointed 'handle' was "RC Flyer." Most
people had no idea what it referred to (radio-controlled model airplanes). Now that
all cellphones use internal antennas, almost nobody even thinks of them as being
radios. CB radios reminded you of their true nature by requiring that a 1/4-wave
vertical antenna (typically with a loading coil to keep it shorter than its 27 MHz
operational frequency...
 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.
Tuesday 31
 Admittedly, with all the reading I have done
of vintage electronics magazines, news of this
Crystron (crystal-electron) vacuum tube device invented by Mr. Mohammed
Ulysses Fips, as reported in the April 1947 issue of Radio Craft magazine,
evaded my attention. The article came only a couple months after publication of
the 40th anniversary edition that celebrated Dr. Lee de Forest's invention
of the Audion tube. According to Mr. Fips, his Crystron one-upped the Audion
by virtue of its containing a small amount of radio isotope which obviated the need
for the traditional "B-battery" concept also developed by de Forest to supply
a high voltage for driving the output stage circuit. While not capable of powering
a concert hall audio speaker system, it did make possible use of a small speaker
as a nearby personal listening device rather than requiring headphones or earbuds.
Without divulging the most critical and closely-held details of the Crystron as
the U.S. Patent Office...
 Artech House today announced the publication
of
High-Power Electromagnetic Effects on Electronic Systems, by D.V. Giri, Richard
Hoad and Frank Sabath. This is the first book that comprehensively addresses the
issues relating to the effects of radio frequency (RF) signals and the environment
of electrical and electronic systems. It covers testing methods as well as methods
to analyze radio frequency. The generation of high-powered electromagnetic (HPEM)
environments, including moderate band damped sinusoidal radiators and hyperband
radiating systems is explored. HPEM effects on component, circuit, sub-system electronics,
as well as system level drawing are discussed. The effects of HPEM on experimental
techniques and the standards which can be used to control tests are described. The
validity of analytical techniques and computational modeling in a HPEM effects context
is also discussed. Insight on HPEM effects experimental techniques...
 MPDevice (MPD) has become a trustworthy
and reliable company in the global RF market as a manufacturer of
passive RF Devices. Included
are attenuators and terminations, coaxial connectors, adapters, and cable assemblies,
DC blocks, surge arrestors, power combiner / dividers, and directional couplers.
The Korean Telecommunication market is now entering into the era of hyperconnected
society. With continuous enhancement in R&D capabilities and quality control,
MPD will continue in an effort to become the No. 1 technologically innovative
company with a focus on the emerging 5G marketplace.
 Pulse compression (aka 'chirp')
radar was invented in the 1950s by Sperry and a couple other defense contractors.
It was new enough by the time the radar I worked on as a technician in the USAF
that it was not incorporated. Our MPN-13 and MPN-14 radar systems used simple single-frequency
pulses. Pulse compression employs a swept frequency within a fairly narrow bandwidth
to exploit the benefits outlined in this 1965 Electronics World article. If you
were to listen to the signal used to sweep the RF pulse in frequency, it would sound
a lot like a bird's chirp, hence the name. Treatment by author Donald Lancaster
is fairly heavy in that it fearlessly presents the mathematical concepts of sin(x)/x
waveforms, Fourier transforms, and weighting. He references Skolnik, Ridenour, et
al. Even so, it is a quick read that provides a good introduction to chirp radar...
Electro-Photonics LLC, a market leader in RF and Microwave components has released
a new series of
band pass filters featuring frequencies from 300 MHz – 50 GHz. Our
new wide bandwidth filters future high stop band suppression and compact size. These
RF/Microwave and mmWave filters can dissipate up to 20 W of continues wave
power. Electro-Photonics, LLC, is a global supplier of high-frequency components
and services. Our products include, SMT hybrid and directional couplers, high frequency
test fixtures, evaluation test boards, and wire bondable passive components.
 PCB Directory is the largest directory of
Printed Circuit Board (PCB) Manufacturers,
Assembly houses, and Design Services on the Internet. We have listed the leading
printed circuit board manufacturers around the world and made them searchable by
their capabilities - Number of laminates used, Board thicknesses supported, Number
of layers supported, Types of substrates (FR-4, Rogers, flexible, rigid), Geographical
location (U.S., China), kinds of services (manufacturing, fabrication, assembly,
prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.
 Two major radio events were covered in this
1954 issue of Radio & TV News magazine's monthly "Spot Radio News"
column - the rapid advance of microwave technology for building out
high capacity voice and television transmission systems, and the ever-increasing
number of new TV station operation license grants since the ending of the Federal
Communications Commission (FCC) moratorium in 1952. In 1944, the FCC stopped issuing
broadcast permits due to serious unforeseen interference from co-location interference
issues as post-war households enthusiastically adopted TV. Unlike today's microwave
relay networks, in the 1950s most systems were still analog in nature. Coaxial cable
installations were good, but use over extra long distances and in difficult to access
areas limited their applicability. Line-of-sight limitations between relay towers
required building more sites than might otherwise be required, but the advantage...
 Here from a 1965 issue of Electronics
World magazine is a really nice write-up on
electrical noise, both how it originates and how it affects receiver systems.
Although vacuum tubes were still the predominant active amplification components
in 1965 (the date of this article), semiconductors were already solidly ensconced
in the signal detector role. I have to confess to learning a new term that I probably
should be familiar with: Equivalent-Noise-Sideband-Input, or ENSI. It appears also
in Reference Data for Engineers: Radio, Electronics, Computer, and Communications.
Interestingly, this is the first time in a long time I have seen noise referred
to as "grass;" the drawings make it clear why the moniker was created. We were taught
to use "grass" in USAF radar tech school and used it in common parlance...
 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 13,000 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. If you need your company news to be seen, RF Cafe is the
place to be. Advertising begins at $40/month.
 The first video below is my favorite. It
is a one-minute clip from a 1960s episode of "The Twilight Zone"
television show. It is an outrageous slam on amateur radio operators by a family
whose radio and TV shows are being interrupted by interference. Dad looks out the
window and sees what are actually television antennas on the guy's roof and when
Mom asks if there is anything they can do about the neighbor, he walks toward the
telephone saying he can at least check to find out whether neighbor man has a license
to operate. Mom then says, "Do you think you should, Stu? Those men seem kind of...threatening
somehow." Those d**n evil Hams! As you might expect if your are familiar with the
series, it turned out to be aliens making contact with Earthlings...
 "Sensing from the inside A mock-up of an
ingestible pill containing the wireless transceiver. Researchers at Imec, a
Leuven, Belgium-based center for nanoelectronics and digital technologies, have
developed a wireless receiver and transmitter small enough to fit inside a millimeter-scale
capsule. The transceiver, which was presented at the International Solid-State Circuits
conference in San Francisco, U.S., last month, is 1/30th the size of today's state-of-the-art
systems and could be used in a broad range of so-called 'ingestibles' - sensors
that monitor health conditions from inside the human body. Like their external,
wearable cousins, ingestible sensors..."
Monday 30
 Empower RF Systems
is a global leader in power amplifier solutions. Empower RF Systems is an established
and technologically superior supplier of high power solid state RF & microwave
amplifiers. Our offerings include modules, intelligent rack-mount amplifiers, and
multi-function RF Power Amplifier solutions to 6 GHz in broadband and band
specific designs. Output power combinations range from tens of watts to multi-kilowatts.
Unprecedented size, weight and power reduction of our amplifiers is superior to
anything in the market at similar frequencies and power levels.
Sunday 29
 This March 29, 2020,
tech-themed crossword puzzle contains only clues and terms associated with engineering,
science, physical, astronomy, mathematics, chemistry, etc., which I have personally
built over nearly two decades. Many new words and company names have been added
that had not even been created when I started in the year 2002. You will never find
a word taxing your knowledge of a numbnut soap opera star or the name of some obscure
village in the Andes mountains. You might, however, encounter the name of a movie
star like Hedy Lamarr or a geographical location like Tunguska, Russia, for reasons
which, if you don't already know, might surprise you...
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.
Homepage Archive Pages
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
|
