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5 of the October 2020 homepage archives.
Wednesday 21
RCA (Radio Corporation of America) is not
really the first company name that comes to mind when thinking about
radar, be it weather, aircraft navigation, or nautical navigation. Instead,
I think of radios and televisions and even satellites; RCA developed the circa 1958
SCORE series. According to this 1955 article in Radio & Television News
magazine, RCA designed and built a a C-band airborne radar system for detecting
adverse weather conditions enroute, at a range of up to 150 miles. Operating at
around 5.4 GHz at 75 kW peak, the AVQ-10 radar unit was primarily meant
for weather avoidance rather than for terrain and aircraft avoidance. The installed
weight of 125 pounds was rather amazing considering the use of vacuum tubes and
a CRT display (also a vacuum tube), along with leaded passive components and bulky,
heavy (relatively) transformers for providing high voltage...
PCBONLINE, a one-stop custom PCB/PCBA manufacturer
for prototypes, small-batch, and massive production, recently published a technical
blog to explain
how to create a custom PCBA. It answers what is a PCBA, how to create a custom
PCBA, the techniques used for manufacturing the PCBA, etc. When a PCB is mounted
with electronic components, it becomes a PCBA (printed circuit board assembly),
which is a semi-finished electronic product that achieves the vital function of
an electronic device. PCBAs are used in almost all electronics industries. PCBAs
manufactured by PCBONLINE include the high frequency PCBA, multilayer PCBA, rigid-flex
PCBA, aluminum PCBA, etc. 1 to 100 layer PCBAs can be delivered in 3 days...
"For around 10 years, smartphones and
computer screens have been based on a display technology composed of so-called thin
film transistors. These are inorganic transistors that require very little power,
and they have proven themselves capable, given their widespread adoption. But they
have limits that researchers have been busy trying to overcome. 'We explore new
ways to improve upon thin film transistors, such as new designs or new methods of
manufacture,' said Gyo Kitahara, a Ph.D. student from the Department of Applied
Physics. 'Organic
thin film transistors, for example, have a bright future in LCD screen devices.
Compared to the inorganic kind currently used..."
Here is an advertisement by
RCA Victor (Radio Corporation of America) from the November 6, 1948, edition
of the The Saturday Evening Post. As was common in the day, the company
specifically addresses Americans in an American magazine. Rarely anymore does a
major American company use the word "America" or "American" in promotional material
because of globalism and the fear of being too committed to the well-being of its
native country. The same is true of most western countries' corporations, where
their country names can be substituted for "America" in this piece. Up through about
the 1980s it was commonplace to specifically address countrymen. Once manufacturers
ramped up offshoring efforts the practice began disappearing. Offshoring is distinctly
different from importing another...
ConductRF is pleased to offer
Low Smoke / Zero Halogen Jacketed RF Cables for various applications Indoor
and Outdoor for Naval Ship-Board applications. We have two ranges of solutions aimed
at differing RF requirements with our SBA series aimed at Higher Frequency 18 GHz
needs. These are 100% factory tested to exacting VSWR and Loss standards because,
We know, Results Count! ConductRF manufactures a range RF Cables in support of Ship
Board applications, where Low Smoke, Zero Halogen requirements are mandated. These
cable have Low Smoke Polyolefin Jackets that are suitable for Ship Board Environments.
The Cable solutions are commonly available in 3 sizes with cable OD of 0.240", 0.405"
and 0.590"...
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.
Tuesday 20
It seems Amateur radio operators in every
country have perpetually been in a battle against government bureaucrats. Early
on, Hams were allocated small segments of available "usable" spectrum and a fairly
wide swath of the less desirable spectrum. That was especially true of the microwave
bands when there was not a lot of components and equipment available that could
operate at the higher frequencies. Those familiar with history are familiar with
the situation where Amateurs developed a lot of the technology for operating in
the upper MHz and into the GHz realm, and then the government snatched it from them
for commercial and military use. Hams pretty much pioneered
atmospheric scatter as a means for long distance (DX), over-the-horizon communications
using those upper frequencies. This editorial from a 1955 issue of Radio & Television
News magazine reports on a relatively newer variation dubbed "forward-scatter,"
which works in 40-80 MHz band (6-meters and VHF) when the transmitted power
is sufficiently high. The military, which discovered the phenomenon and had recently
declassified it, was considering allowing Amateurs...
"Researchers at UNSW Sydney have demonstrated
the lowest noise level on record for a
semiconductor quantum bit, or qubit. The research was published in Advanced
Materials. For quantum computers to perform useful calculations, quantum information
must be close to 100 percent accurate. Charge noise - caused by imperfections in
the material environment that hosts qubits - interferes with quantum information
encoded on qubits, impacting the accuracy of the information. "The level of charge
noise in semiconductor qubits has been a critical obstacle to achieving the accuracy
levels we need for large-scale error-corrected quantum computers," says lead author
Ludwik Kranz, a Ph.D. student at UNSW's Centre for Quantum Computation and Communication
Technology (CQC2T) working with the Centre's spin off company Silicon Quantum Computing
(SQC)..."
RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave component
supplier. RF coaxial connectors & adapters, coaxial cable & cable assemblies,
surge protectors, attenuators. Items added daily. Free shipping on orders over $25.
We're leading the way again!
This
Electronic Menu Quiz appeared in the August 1963 edition of Popular Electronics
magazine. Robert Balin created many such quizzes for Popular Electronics
over the years. It challenges you to match the common food-related term for a device
with its picture. If you've been around electronics labs and/or read electronics
hobbyist magazines for a while, chances are you have run across most of the terms.
I suggest you click on the image to get a full-size view of the drawings to be able
to see all the detail. A couple of the names I have to admit not being familiar,
so they seem rather 'corny'... get it?
Each
month the ARRL's flagship magazine, QST, makes an article available for
free to non-members. November's selection is entitled "Military
Mast Problems and Solutions." Bob Dixon, W8ERD, begins: "Many of us use military
surplus masts and tripods to hold up antennas, especially in portable situations.
They work very well, but these masts have potential stability problems, because
the adjacent mast sections and tripod are held together by their weight and by friction
alone. If the mast is tilted by the wind or pulled by a wire, the mast joints and
tripod can separate, and the entire structure can fall down catastrophically. Also,
if you have a rotatable antenna on the mast, the mast sections can slip and rotate
the antenna, or make it difficult to turn. These problems can be fixed by pinning
all the mast sections and the tripod together..."
Skyworks is pleased to introduce the
SKYFR-001982, a small form factor surface mount circulator for L-Band radar
systems and wireless applications in the 1200-1400 MHz operating range. This
device offers high power level handling with minimal thermal rise, providing a flow
path for the RF signal as well as protection for sensitive components from excess
signal reflection. Packaged in a compact SMT housing, the SKYFR-001982 can be easily
incorporated onto PCB boards with automated pick and place manufacturing. The SKYFR-001982
is the latest in Skyworks' broad portfolio of Circulator and Isolator products for
radars for both military and commercial applications...
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.
Monday 19
I'm always tempted to wax nostalgic over
ads like this one since they remind me of more care-free childhood and early teenage
years when our household had the typical single television set with an antenna on
the roof and a
300 Ω twin lead cable running haphazardly down the roof surface and over
the metal gutter, stretching under the eave to where it was crushed between the
window sill and lower window pane, and snaked along the wall and floor to the TV.
In the early days, our antenna was fixed (no rotator). Situated in Mayo, Maryland,
about midway between Baltimore and Washington, D.C., where our nearest broadcast
stations resided, we somehow managed to get acceptable reception on our low-end
black & white television. I don't recall in which direction the antenna was
pointed (maybe northwestish to cover both directions equally). It wasn't until sometime
in the early 1970s that we finally got our first color TV that the system showed
its weakness...
"Special operations commands across Europe
are ramping up their capabilities with
high-frequency communications to ensure connectivity on the battlefield. Leaders
there are turning to high frequency communications as a way to optimize properties
that provide a low probability of interception and detection. Special forces in
France, Germany, Poland and Ukraine continue to receive high-frequency, or HF, systems
as a way to diversify communications plans, industry sources confirmed to C4ISRNET.
Some special operations organizations have selected L3Harris' AN/PRC-160(V), industry
sources said. Enhancements in HF come at a time when NATO members and partner forces..."
As mentioned in an earlier post, a while
back I bought a box full of vintage Old Farmer's Almanacs (OFA) at a yard
sale, figuring there would be a bunch of good items to post here on
RF Cafe and on my
Airplanes and Rockets hobby website.
Chief amongst the postworthy features is the Mathematical Puzzles section. They
are a fair challenge to an engineer's cerebration, contemplation, and deliberation.
These particular mathematical posers appeared in the 1974 issue of OFA.
#10, while rated a difficulty of 4 (where 5 is most difficult), is really not even
a mathematical challenge when you think about it (hint - it's an old riddle you've
probably seen before). Enjoy!
"Handie-Talkie"
was the name given to early walkie-talkies used in the field by military communications
troops. Having been written during World War II, the author of this QST
article just assumed that any reader would be familiar with the WERS acronym - it
stands for War Emergency Radio Service. Per the Wikipedia entry: "At the start of
the Second World War the United States Congress had suspended all amateur radio
activity throughout the country. WERS was established by the Federal Communications
Commission in June 1942 at the insistence of the American Radio Relay League. WERS
would remain in operation in through the end of the Second World War in 1945. WERS
was to provide communications in connection with air raid protection, and communications
during times of natural disaster. WERS licenses were given to communities and not
individuals...
Anatech Electronics (AEI) manufactures and
supplies RF and microwave
filters for military and commercial communication systems, providing standard
LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard
RF filter and cable assembly products are published in our website database for
ease of procurement. Custom RF filters designs are used when a standard cannot be
found, or the requirements dictate a custom approach for your military and commercial
communications needs. Sam Benzacar's monthly newsletters address contemporary wireless
subjects. Please visit Anatech today to see how they can help your project succeed.
This is not something devised by Benjamin
Franklin. Rather, the American Radio Relay League (ARRL) sold a variety of these
"Lightning
Calculator" slide rules in the days before electronic calculators. This "Type
B" version (copyright 1932, W.P. Koechel) calculates Ohm's Laws values for
resistance, voltage, current, and power. As shown here, it indicates an alignment
of 1 V, 1 A, and 1 Ω. The Lightning Calculators" were rather large
at 8½" wide by 11" high. Being the size of a sheet of paper, it is surprising they
did not come with holes for a 3-ring binder. There were six varieties of "Lightning
Calculators," as shown in the 1939 QST magazine advertisement. Thanks to
Joe Birsa (N3TTE) for the donation.
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 18
October 18th's custom
Science and Engineering Technology themed crossword puzzle contains only only
words from my custom-created lexicon related to engineering, science, mathematics,
chemistry, physics, astronomy, etc. (1,000s of them). You will never find among
the words names of politicians, mountain ranges, exotic foods or plants, movie stars,
or anything of the sort. You might, however, find someone or something in the otherwise
excluded list directly related to this puzzle's technology theme, such as Hedy Lamarr
or the Bikini Atoll, respectively. The technically inclined cruciverbalists amongst
us will appreciate the effort.
Friday 15
That would be President Ford in the background
atop the platform, behind where the
OSCAR ground station was set up. He was there as part of the dedication of the
new National Air & Space Museum in Washington, D.C., in 1976. The event was
part of the nationwide series of bicentennial celebrations marking America's founding
with the signing of the The unanimous Declaration of the thirteen united States
of America. Apollo 11 astronaut Michael Collins directed the event. The Space
Race was in its heyday and most people were still in awe of anything related to
spacecraft - both manned and unmanned. Just about anyone other than a Ham radio
operator believed communicating with a satellite was the exclusive domain of governments,
so the presence of AMSAT...
"Analog computing with
neuron-like devices could efficiently solve problems traditional computers struggle
with. One thing that's kept engineers from copying the brain's power efficiency
and quirky computational skill is the lack of an electronic device that can, all
on its own, act like a neuron. It would take a special kind of device to do that,
one whose behavior is more complex than any yet created. Suhas Kumar of Hewlett
Packard Laboratories, R. Stanley Williams now at Texas A&M, and the late Stanford
student Ziwen Wang have invented a device that meets those requirements. On its
own, using a simple DC voltage as the input, the device outputs not just simple
spikes, as some other devices..."
Reading through this article reminds me of
studying for the amateur radio exams. In fact, the information presented in this
1940 QST piece does not seem to be lacking anything that contemporary discussions
include. My point is that a great amount of knowledge had already been amassed about
earth's upper atmosphere a mere four decades after the first
transatlantic radio communications were accomplished by Marconi on December
12, 1901 from Poldhu in Cornwall, England, to Newfoundland, Canada. Considering
that at the time no instrumented sounding rockets had been launched into the extreme
upper layers (F1 & F2, beginning at around 120 mi | 200 km), a lot had been
discerned about characteristics as they pertain to radio communications. Balloons
were used for direct measurements...
In his latest The Accidental Engineer
blog post, Reactel's Jim Assurian offers his assessment of the first-ever
Virtual
IMS (vIMS), made necessary by the COVID-19 worldwide epidemic this year compliments
of Wuhan, China. Jim begins: "Some contemplative reactions to the Virtual IMS from
an Exhibitor - the comments are my own and may not be indicative of other's experience
or their impression of the vIMS. The live portion of the Virtual IMS concluded on
August 6th though much of the Conference is available On-Demand thru September 30th.
I encourage you to visit the Conference website. If I had to rate my experience
with the vIMS on a scale of 1 thru 5, I'd give it a 1. I was underwhelmed by the
interface as I noted in my earlier blog post, and the 'traffic' through my booth
was minimal at best. Once I subtracted out the industry friends who swung past for
a look..."
Reading trade journals is always given as
one of the main ways cited by engineers on career surveys for continuing education.
Engineering whitepapers, pamphlets,
books, magazines, and chapter examples listed here are a small sample of a lot
of new items that are offered for FREE through TradePub. The publishers make them
available to qualifying people as a promotional campaign for their full line of
offerings. Whitepaper topics include careers, manufacturing, and engineering, while
magazine titles include NASA Tech Briefs, Electronic Component News, and Microwave
Product Digest. Note: I earn a few pennies (literally) when you download one of
these or the many other pubs available, so please help yourself.
Res-Net Microwave has a complete line of precision
RF & microwave components
including attenuators, terminations, resistors, and diode detectors for commercial,
military, and space applications. Products range from the small flange type to large
2,000 watt connectorized power attenuators and/or terminations at frequencies up
to 26.5 GHz. In-house photo etch and laser trim capability. The company is
a leader in development and production of the films required for these type of RF/microwave
components. Please check out Res-Net Microwave's website to see how they can help
with your current project.
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