See Page 1 |
2 |
3 |
4 | of the May 2020 homepage archives.
Sunday 31
This week's
crossword
puzzle is a new type that uses a "free form" layout where the software dynamically
creates the word grid, rather than beginning with a predefined grid that it then
fills with words. It appears the longer it is allowed to run, the greater the number
of words and cross-links it creates. After about 5 minutes, this 19x17 grid is showing
57 words and 61 cross-links... and now an hour later it shows 62 words and 70 cross-links
- not overly impressive in my view. The algorithm picks from the same database of
thousands of words which I have been creating for over twenty years and contains
only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, familiar company names 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...
Friday 29
Electronics wizard, repairman, and experimenter
extraordinaire Mac McGregor, as sort of alter ego of author John T. Frye, provides
a brief lesson on electrostatics for his repair shop apprentice wing man Barney
(I don't think his last name was ever mentioned). In this 1973 Popular Electronics
magazine article, Mac had built two types of
electroscopes - one using a pair of pith balls suspended from silk strings and
another that was a cobbled-together version of a gold leaf electroscope. His motive
was two-fold. First and foremost was to accommodate his own interest in electrostatics,
and second to hopefully engender enough curiosity in Barney to cause him to do a
dive into science books to learn more. Given the potentially lethal levels of electrostatic
charge that builds on TV picture tubes they worked around, gaining a healthy respect
for an electrostatic charge...
"As countries around the world begin rolling
out 5G wireless networks, CEA-Leti, a technology research institute, is looking
ahead to
6G technologies that will surpass the data-transfer capability of 5G. The wireless
communication in mm-Wave bands, ranging from 20 to 300 GHz, is expected to be a
key enabling technology for 6G wireless systems. This is because of the huge available
bandwidth that can accommodate ultra-high data-rate communications. Within that
range of mmWave bands, CEA-Leti's research is investigating D-band, a new spectrum
at 140 GHz that may play a major role in 6G wireless communication. In a paper written
for the 6G Wireless Summit, which was scheduled to take place in March but got cancelled
because of the coronavirus pandemic, CEA-Leti, and Siradel, a French engineering...
"
Frequency modulation (FM) was, is, and always
shall be: x(t) = Xc·cos [Ωct + β·sin (Ωmt)], where
the carrier is xc(t) = Xc·cos (Ωct), and the modulating
signal is xm(t) = β·sin (Ωmt). Yea verily, thus sayeth Edwin
H. Armstrong. Amen, brothers and sisters of radio. The methods for generating and
degenerating[sic] FM might vary, but the fundamentals do not vary. Mr. Armstrong
developed and patented his system of frequency modulation in the late 1920s and
early 1930s, so when this article appeared in QST in 1939, FM was still fairly new
- or even unknown - to most people. Household radio dials still had only markings
for the commercial AM band (520 - 1720 kHz) and, in a few cases, a couple shortwave
bands (also AM)...
Withwave's Precision Test Adapters
are designed based on precision microwave interconnection technologies. These new
2.92 mm to 3.5 mm types are manufactured to precise microwave specifications
and constructed with male and female gender on both sides. The precision microwave
connector interfaces ensure an excellent microwave performance of 1.25:1 (max) VSWR
up to 34 GHz.
"Microwave
Filters, Impedance-Matching Networks, and Coupling Structures," by Matthaei,
Young, and Jones, is another classic text that was a go-to reference for filter
designers before desktop synthesis software was commonplace. It is also available
on the Archive.org website - all 1,115 pages of it. While you are at Archive.org,
do a search on any topic of interest and likely you will receive more sources than
you ever dreamed were available on the Internet. That includes books, technical
reports, white papers, magazine articles, videos, audios, music, podcasts, and other
media formats. It is truly a unique and indispensible repository of information.
The WayBack Machine has been
capturing website pages for more than two decades. It has collected pages from RFCafe.com
during 888 sessions between October 13, 1999 and May 13, 2020.
KR Electronics designs and manufactures
high quality filters for both the commercial and military markets. KR Electronics'
line of filters includes lowpass,
highpass, bandpass, bandstop and individually synthesized filters for special applications
- both commercial and military. State of the art computer synthesis, analysis and
test methods are used to meet the most challenging specifications. All common connector
types and package form factors are available. Please visit their website today to
see how they might be of assistance. Products are designed and manufactured in the
USA.
Thursday 28
This is the
electronics market prediction for Sweden, circa 1966. It was part of a comprehensive
assessment by the editors of Electronics magazine of the state of commercial, military,
and consumer electronics at the end of 1965. Among Sweden's modern-day most recognizable
electronics and related manufacturers are Ericsson, Saab Group and Electrolux, in
existence in one form or another since 1965. Automotive company Volvo is also among
the largest manufacturers there, although not specifically of electronics. A number
of contemporary resources are available for obtaining reports (at a cost) on the
electronics industry in almost every country on Earth. Among them are "Consumer
Electronics in Sweden, August 2019" and "Electronics Industry in Sweden June 2019..."
Cadence| AWR will host a free webinar entitled
"AWR Software Web-Training on
mmWave MIMO Radar System Design," presented by RF filter expert Dr. Tero
Kiuru. Overview: This web-based training session uses Cadence® AWR Design Environment®
software to illustrate the design of a frequency modulated continuous wave (FMCW)
multiple-in-multiple-out (MIMO) radar system for short range high resolution localization
of nearby moving objects. Dr. Tero Kiuru, of the VTT Technical Research Centre of
Finland Ltd., is an expert in front-end component design. Four-channel transmitter
and receiver chips will be designed using a 130 nm silicon germanium (SiGe)
process. Measurements will be made with a 4 TX channel and 8 RX channel
system and simulation versus measurement results...
This
news item is worth reading if only for the reader comments at the bottom of the
page - which is often the best part of any new story, BTW. The author, who extols
the virtues of this
fossil fuel-less jet propulsion scheme, does not say from whence the the massive
amount of energy for generating microwaves comes - an onboard nuclear power generator
perhaps. My thought was, considering this research came out of the Institute of
Technological Sciences at Wuhan University, China, that the hope is those
foreign devils will glom onto
the concept to create jet planes and drones with the most massive electromagnetic
signature a smart missile could ever hope for. Rumor |one I just made up ;-)|
has it the project is code named COVID, for Cavity Oscillator Velocity-Inducing
Deception.
EMC Directory, a new addition to the
everythingRF network of engineering resources, is the largest online directory
of EMC / EMI Testing labs. The website makes it easy for users to find
EMC labs based on their location and testing capabilities. Users can specify the
application like Automotive, Radio Technology, Industrial, Medical etc. to find
labs that can carry out the test in a specific region. They can also find labs based
on the testing directive like CISPR 11, FCC Part 15 (Sub part b) or ISO 10605. EMC
testing is performed to ensure that the electronic devices: Have sufficient immunity
to electromagnetic interference. They do not create excessive electromagnetic radiation
EMC Testing is a very important area for most engineers and companies. Regulatory
bodies around the world like FCC, CE, have placed limits on the levels of emissions
that electronic and electrical products can generate...
If it seems like I use opening phrases like,
"Back in the days before..." and "There was time when..." a lot, it is because I
do, and unabashedly so. The measure of oldness of time past is relative and objective,
and unless a particular bit of information on a topic has been proven false or unreliable,
there is value in its continued existence and in its continued use as a reference.
Such is the case of a book that used to be found somewhere in the offices of every
electrical design company: "Handbook
of Filter Synthesis," by Anatol Zverev. Another filter design standard tome
is "The Design
of Filters Using the Catalogue of Normalized Low-pass Filters," by Rufolph Saal.
General Electric AESD, in Utica, NY, my first company after graduation, had them
in the library. The latter has been uploaded in its entirety to Archive.org by RF
Cafe visitor Brad B. The former is also on Archive.org compliments of another
Good Samaritan. We thank them both.
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.
Wednesday 27
In the days before people were so easily
offended by light-hearted poking, it was not uncommon to find magazine articles
written by the wives of hobbyist husbands lamenting the habits and proclivities
of their matrimonial mates. Over the years I have read many such treatises in model
and full-scale airplane, electronics, and Ham radio publications. As with "A
Radioman's Wife Puts in a Good Word" from a 1951 issue of Radio-Electronics,
they typically start by expressing frustration of having lost their once-doting
husbands to alternative loves in the form of hobbies (I once saw a boat named "The
Other Woman"). Determined to win back the devotion of their sweethearts, they make
a sincere attempt to learn about and be part of whatever hobby or hobbies is/are
the cause of abandonment of wife and children. It usually doesn't take long for
Friend Wife, as Popular Electronics' Carl Kohler addresses his better half, to decide
that try as she may, engendering a sufficient...
Z-Communications, Inc., announces the RoHS
compliant VCO (Voltage-Controlled Oscillator) model
SMV4596L-LF for highly stable clock generators. The SMV4596L-LF covers 4595
to 4598 MHz within a tuning voltage range of 0 to 2.5 Vdc. This low cost
VCO consumes typically less than 15mW of power while still delivering phase noise
performance of -81 dBc/Hz @ 10 kHz offset. This unparalleled VCO operates
off a 2.8 Vdc supply while drawing a mere 5mA of current. The SMV4596L-LF is
designed to deliver -1±2 dBm of output power into a 50 ohm load while
operating over the industrial temperature range of -40 to 85°C. This remarkable
VCO is further enhanced by its better than 1.1:1...
After decades of politicians and industry
titans dodging blame for things that go wrong on their watch and demanding full
credit for what goes right, it is refreshing to be read this statement from
SpaceX's Elon Musk, "I'm the chief engineer of this thing so I'd just like to
say that if it goes right, it's credit to the SpaceX-NASA team. If it goes wrong,
it's my fault." This is just ahead of the planned historic launch of NASA astronauts
from Cape Canaveral this evening, Wednesday 27th, at 4:33 pm. Astronauts Bob
Behnken and Doug Hurley will be launched to the International Space Station in a
SpaceX Crew Dragon spacecraft atop a Falcon 9 rocket. The launch is the first
time that astronauts have launched from American soil since 2011 when the Space
Shuttle program was axed. Since that time we have paid the Communist nations of
China and Russia to ferry our astronauts to and from space. Imagine the technology
we had to transfer to them to get a safe ride! Watch the launch live on
NASA TV.
Gray market electronics components have been
a problem for a long time. An extensive article appeared recently in EE Times
reporting on a case based on a small operation in south Florida that was importing
and re-selling counterfeit parts to military, aerospace, medical, and other product
manufacturers. The Feds charged them "with conspiracy, trafficking in counterfeit
goods and mail fraud for knowingly importing more than 3,200 shipments of suspected
or confirmed counterfeit semiconductors into the United States, marketing some of
the products as "military grade" and selling them to customers that included the
U.S. Navy and defense contractors." The good news might be that this particular
scam operation was caught and stopped, but the bad news is, according to the story,
that many more are never prosecuted...
ConductRF offers RF Engineers a large selection
of
Hi Flex cable for vector network analyzers (VNAs). We have standards for applications
at 18-40 GHz, 50 GHz & 70 GHz. Our torque resistant connector
heads and phase stable constructions ensure great performance for many tests to
come. Other key features include: 2.92 mm, 2.4 mm & 1.85 mm connector
options, low VSWR & insertion loss, low phase change with flexing, options available
swept right angle connectors. ConductRF VNA series provides customers with reliable
ruggedized solutions for Lab and Production Vector Network Analyzer testing. With
options for 18 GHz, 26.5 GHz, 40 GHz, 50 GHz, & 70 GHz,
these cables offer cost leading alternatives to original OEM VNA cable solutions...
Innovative Power Products (IPP) has over
30 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband couplers, combiners, resistors, baluns, terminations and attenuators
are fabricated using the latest materials and design tools available, resulting
in unrivaled product performance. Applications in military, medical, industrial
and commercial markets. Take a couple minutes to visit their website and see how
IPP can help you today.
Tuesday 26
Most people who have been in the electronics
world for a while know that neon light bulbs* used to be commonly employed as a
"pert-near" voltage regulator reference of between 55 and 65 volts, depending on
the type. The familiar NE-2 has a turn-on voltage of 65 Vac (90 Vdc),
for instance, and the voltage across the terminals remains there with little change
regardless of the current through the bulb - a lot like a Zener diode. Neon bulbs
are also used as non-invasive RF power detectors. Most people probably do not know,
however, that incandescent bulbs also have properties that make them useful for
purposes other than just lighting up a dark space.
Incandescent light bulbs have been used successfully for voltage regulation
and RF power measurement. They have also been used as dummy loads for transmitters.
John Parchman details some of these uses...
Triad RF Systems continues to add to its
THPR series of
ready-to-install amplified radios. Eliminating the need to integrate standalone
components to create a long-range wireless and intelligence, surveillance, and recognizance
(ISR) radio links working in S-band, Triad has combined high power RF subsystems
with a Silvus StreamCaster model SC4210E-235 core radio that operates from 2,200
to 2,500 MHz. Triad model THPR1012 is an efficiently packaged, highly reliable,
dual-channel MIMO, turnkey radio system that includes bi-directional amplifiers
(BDAs), RF filtering, real-time power measurements, link diagnostics, and innovative
SoC-based monitoring and controls. This integrated amplified radio system delivers
maximum power output of 40 W at 9 Mbps on its max power setting, and 10 W
at ~60 Mbps on its max data rate setting. Unmanned system engineers can expect
dependable RF link stability and up to 10X extra range...
"A U.S. federal judge has given permission
to retrieve the ill-fated
RMS Titanic's Marconi wireless gear, which transmitted distress calls from the
sinking ocean liner during its maiden voyage. [The judge] ruled that the radio gear
is historically and culturally important and could soon be lost within the rapidly
decaying wreck. The Titanic sank after striking an iceberg some 370 miles off the
coast of Newfoundland in 1912. 'The Marconi device has significant historical, educational,
scientific, and cultural value as the device used to make distress calls while the
Titanic was sinking,' Judge Smith wrote in her ruling. She said the company would
be permitted 'minimally to cut into the wreck' to access the radio room. The National
Oceanic and Atmospheric Administration (NOAA) contends that the retrieval expedition
is still prohibited under US law and under an international agreement between the
US and the UK..."
Electro-Photonics is a global supplier of
RF & Microwave components.
Their products include SMT hybrid and directional couplers, wire bondable passive
components, mounting tabs, filters, transmission lines, and very useful test boards
for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics
team can support your small R&D design requirements with RF & Microwave
test fixtures and save you valuable design and characterization time. Please take
a moment to visit Electro-Photonics' website and see how your project might benefit.
"Are
we killing the broadcasting goose, layer of many golden eggs?" Dr. Lee de Forest
asked in his inaugural address, upon his election to the presidency of the Institute
of Radio Engineers. So went the opening editorial in a 1930 edition of Radio
News magazine. It was directed at the question of whether excessive, "gratuitous"
advertising was going to be so offensive to listeners that they would turn off the
set and go back to their former silent worlds. Remember that many, if not most,
households, and certainly not automobiles, even had radios at the time. Building
an audience was essential to nurturing the new phenomenon of radio, and to saturate
the listeners with commercials would surely doom the medium. Dr. de Forest would
be truly depressed if he could see the commercial broadcast landscape today with
it consisting of 15-20% advertising content and much of the rest filled with political...
Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly for design
engineers needing low volume or prototype multi-layer printed circuit boards.
Free
Passive Components: Bittele Electronics is taking one further
step in its commitment of offering the best service to clients of its PCB assembly
business. Bittele is now offering common passive components to its clients FREE
of Charge.
Monday 25
We all know that for the most part television
stinks. Back in 1951 when this article appeared in Radio-Electronics magazine,
the technology was very new and it was considered a miracle not to be wasted on
inane programming. Newscasts actually presented news and not opinion, movies and
sitcoms cast the nuclear family, law enforcement, the military, religion, and patriotism
in a positive light rather than as the purveyors of evil in the world. By the end
of the 1960s to early 1970s a lot of that had changed. Political and social agendas
weaseled their way into nearly all programming to the extent that terms like "boob
tube" and even, yes, "smellivision,"
became common monikers for television. The form of smellivision presented in this
article was granted patent (US2540144A) protection in 1951 under the title, Television
with scent effects..."
RF Cafe visitor Brad B. just provided
the following
Watkins-Johnson Tech Notes for the collection: v5-3, v5-4, v5-5, v5-6, v6-2,
v6-3, v6-4, v6-5, v6-6, v8-1, v8-4, v9-1, v9-2, v9-3, v9-4, v9-5, v10-2, v10-5,
v10-6. They run the gamut from Solid State Limiting Amplifiers and Antenna Polarizations
to Digital Signal Processing for Multichannel Receiving Systems. Many old-timers
consider the W-J Tech Notes to be some of the best sources of circuit and systems
design guides ever written, especially for military, defense, and aerospace applications.
In this episode of John T. Frye's "Carl &
Jerry" series, the intrepid pair of teenage electronics hobbyists and Ham radio
operators are experimenting with an audio amplifier rig that uses a parabolic dish
for concentrating sound waves at a focal point where they have a microphone mounted.
Aside from picking up bird noises and a neighbor lady scolding her husband for not
properly washing the windows during a round of Spring cleaning, Carl imposes upon
Jerry for a lesson in
feedback techniques - both positive and negative - and the reasons one is preferred
over the other. The story winds up with a clever double entendre comment referring
to osculation...'
"Researchers from the U.S. Naval Research
Laboratory have developed a new Gallium Nitride (GaN) based electrical component
called a
Resonant Tunneling Diode (RTD) with performance beyond the anticipated speed
of 5G. David Storm, a research physicist, and Tyler Growden, an electrical engineer,
the brains behind the electronic component diode, reported their findings in the
academic journal Applied Physics Letters. The work showed that gallium nitride-based
RTDs are not inherently slow, as others suggested. They compare well in both frequency
and output power to RTDs of different materials. The diodes enable extremely fast
transport of electrons to take advantage of a phenomenon called quantum tunneling.
In this tunneling, electrons create current by moving through physical barriers,
taking advantage of their ability to behave as both particles and waves..."
Alliance Test Equipment sells
used / refurbished test
equipment and offers short- and long-term rentals. They also offer repair, maintenance
and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix,
Anritsu, Fluke, R&S and other major brands. A global organization with ability
to source hard to find equipment through our network of suppliers. Alliance Test
will purchase your excess test equipment in large or small lots. Please visit Allied
Test Equipment today to see how they can help your project.
Sunday 24
Beginning in the year 2000 and running through
today, May 24, 2020, I have been creating weekly custom
technology-themed
crossword puzzles for the brain-exercising benefit and pleasure of RF Cafe visitors
who are fellow cruciverbalists. A database of thousands of words has been built
up over the years and contains only clues and terms associated with engineering,
science, physical, astronomy, mathematics, chemistry, familiar company names 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, 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. I also
have an extensive list of
Recently Added topics.
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