Today in Science History -
This is the eighth
and final installment on a "Microwaves" series of articles in
Radio-Electronics magazine by author C.W. Palmer. Each part is a
stand-alone tutorial that does not rely on previous parts to be useful. Unlike
most of the preceding articles that dealt in one way or another with waveguide,
this final one concerns "receiving
and transmitting antennas for microwave communication." It touches lightly
on various types of antennas, field patterns, impedance matching, and
applications. If you've been around for a while, you've likely seen it all
before, but there are some nice photos of antennas designed and deployed by Bell
Telephone Laboratories for their nationwide microwave telephone relay network.
Bell Labs has done a lot of ground-breaking research in all aspects of
"Designing semiconductor circuits hand-in-hand
microfluidic cooling systems could mean huge boosts in efficiency. The heat
generated by today's densely-packed electronics is a costly resource drain. To
keep systems at the right temperature for optimal computational performance,
data center cooling in the U.S. consumes the as much energy and water as all the
residents of the city of Philadelphia. Now, by integrating liquid cooling
channels directly into semiconductor chips, researchers hope to reduce that
drain at least in power electronics devices, making them smaller, cheaper and
less energy-intensive. Traditionally, the electronics and the heat management
system are designed and made separately..."
Kenneth Wyatt has a good article on the
EDN website entitled, "Quickly
Assess Relative Coax-Cable-Shielding Quality." It begins: "Testing most
products for radiated emissions usually requires all I/O and power cables to be
attached to the equipment under test (EUT) and spread out in accordance with the
specific product standard. In many cases, we test engineers simply grab the
nearest cables and hope for the best during the compliance test. Unfortunately,
poor-quality cables can lead to emissions failures due to poor shielding or poor
shield termination (via 'pigtails') to the connectors. In an earlier article, I
related the issue of HDMI cable radiation due to shield pigtails. I also
graphically demonstrate why cable shield pigtails lead to radiated emissions in
the video. In addition to the shield pigtail issue, coax cables..."
WWV is the oldest continuously-operating
radio station in the U.S. since first going on the air from Washington, D.C. in
May 1920. It moved around an area near D.C. for a few years before being relocated
to its current location in Boulder, Colorado, in 1966. WWVB, another time standard
transmitter, had already been established in Boulder a few years earlier. Sister
station WWVH is located in Hawaii. The National Bureau of Standards (NBS) was renamed
National Institute of Standards and Technology (NIST) in 1988, nearly a century
after its inception in 1890. Having grown up not too far from Beltsville, Maryland,
I remember driving by their main campus when the NBS sign was still on the lawn.
The decision to change the name never did make sense, but then most of what government
bureaucrats do perplex me...
In response to an article about the ongoing Wuhan Flu serum development
programs, here is one of the cleverest online forum posts I've ever seen: "This might surprise many of you, but I volunteered for the vaccine trials for
Covid-19. The vaccine is the one that was created in Russia. I received my first
shot yesterday and I'm excited because it seems completely safe, with иo side
effects whatsoeveя, and I feel sκ χoρoshό я чувствую себя немного странно и я
думаю, что вытащил ослиные уши." Plug the Ruskie part into a
Aegis Power Systems is a leading supplier
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Little known to most people (including moi
until recently), DeForest Training School was started by DeVry University's founder
Herman A. DeVry. DeVry and DeForest were DeGood DeFriends, leading DeVry to name
his electronics school after DeForest. It was re-named DeVry Technical Institute
in 1953. Research at DeForest Training School produced one of the first
RF / microwave food baking "ovens." The prototype reported in this 1951
Radio & Television News magazine article was not at all like modern microwave
ovens. There was no enclosure into which baking bowls, pans, and dishes can be inserted.
Rather, electrodes were arranged at the perimeters of the special pan that in this
demonstration contained cake batter. It was adapted from a process originally developed
for RF induction heating of industrial materials...
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.
"Satellite and spacecraft system designers
have a few different options when selecting field programmable gate arrays (FPGA)
semiconductors. One FPGA option is commercial off-the-shelf (COTS) components that
reduce component unit cost and lead time, but they are generally not reliable enough,
must be up-screened (which increases cost and engineering resources), and require
soft and hard Triple Modular Redundancy (TMR) to
mitigate radiation effects in space. In missions where failure is not an option,
designers typically choose higher-cost FPGAs that are radiation-hardened by design
(RHBD). These are already screened and qualified to Qualified Manufacturers List
(QML) Class Q and V standards..."
with Harbaugh" was a regular comic feature in Popular Electronics magazine
in the 1960s. Creator Dave Harbaugh chose topics ranging from husband-wife relationships
where the husband is a technophile of some sort and the wife either purposely or
unknowingly challenges his efforts to participate in his hobby, to contemporary
(at the time) subjects such as this month's treatment of biocells. Like solid state
electronics back in the day, bioengineering was a mysterious field few understood.
It received a great deal of attention by comedians and sci-fi film makers who got
a kick out of scaring people over the possibility of an alien contamination (a la
"The Andromeda Strain") or some secret government laboratory brewing up a deadly
Anatech Electronics offers the industry's
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On September 29th beginning at Noon EDT, Cadence
| AWR will be presenting a free webinar entitled
NCSU Rabbit Radar - Design, Simulate & Build Your Own Radar at Home. "In
this webinar, Dr. Ricketts describes how to design, simulate, and build a 2.4GHz
frequency modulated continuous wave (FMCW) radar at home or in a lab. The webinar
begins with a short theory session followed by an explanation of the key components
of an FMCW radar, which include a mixer, power amplifier, coupler, low noise amplifier,
and filters. The components will use transmission line structures that attendees
NorthEast RF's comprehensive
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Use of the word "modern" in titles of books
and magazine articles has always bothered me because of how quickly the referenced
topic becomes obsolete. It is only "modern" for a relatively short period of time.
In 1951 when this article appeared in Radio & Television News magazine,
germanium was the dominant semiconductor in use for
diodes and transistors. They could be used in small signal circuits of up to
about 500 MHz. That meant they could easily replace vacuum tubes in AM and
FM radios, and at least the IF and baseband sections of TVs. You might think that
would have represented a big component cost savings, but semiconductors were much
more expensive than vacuum tubes at the time. Still, the power savings, size reduction,
and higher reliability made the circuit changes worthwhile...
"A team of researchers at HRL laboratories,
led by Principal Investigator Dr. Jeong-Sun Moon, is developing the next generation
Gallium Nitride (GaN) transistors that will have a dramatic effect on electronic
components that amplify electromagnetic signals for communications, radar, and 5G
wireless networks. The ultra-linear monolithic microwave integrated circuit (MMIC)
amplifiers that utilize these high-speed GaN transistors can see greatly improved
linearity, noise reduction, and reduced power consumption. Moon's team has successfully
met and exceeded the performance metrics defined by the Dynamic Range-enhanced Electronics
and Materials (DREaM) program, a DARPA effort to improve dynamic range in millimeter-wave..."
Innovative Power Products (IPP), a company
with over 35 years of experience designing and manufacturing RF and microwave passive
components, wants to immediately fill an opening for an
RF/Microwave Design Engineer. The position requires demonstrated success in
the design and test of wide band, high power RF and microwave passive components.
Candidate to be familiar with linear and full-wave EM simulators. Responsibilities
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Train and support technicians on S-parameters, test procedures, troubleshooting,
and documentation of product...
Instrument Landing Systems (ILS) has been around since the early 1930s, as made
apparent by this article in Short Wave Craft magazine. Frequencies, circuits,
and infrastructure equipment have evolved over the years, but fundamentally, landing
an aircraft (airplane, helicopter, dirigible) under 'blind' flying conditions has
not changed. Two precision beams - one in elevation and one in azimuth - broadcast
by ground-based installations are detected by airborne receivers and relative positions
are displayed for the pilot's use in navigation. ILS does not help the pilot fly
the aircraft; it only leads him to the runway threshold. In the past couple decades,
space-based Global Positioning System (GPS) equipment has increasingly been used
to replace ground-based microwave systems...
Teledyne e2v HiRel, part of the Teledyne
Defense Electronics Group, today announced the latest addition to its rapidly expanding
line of RF solutions, a new
RF MMIC Frequency Doubler. Launching Teledyne e2v HiRel's new Frequency Multiplier
product line, this Active Doubler, TDFM001000, is designed for high reliability
signal chain applications in Space. It is particularly well-suited specifically
for satellite transponders, transmit/receive modules, microwave-based communications,
millimeter-wave point-to-point radio, and related processes. The TDFM001000 is a
7.5-25.0 / 15.0-50.0 GHz single ended input (no external balun required) GaAs
The October issue of IEEE's Spectrum magazine
ran an article entitled, "Let
a Thousand Analog Oscillators Sing." It reports on Sam Battle's "KiloDrone"
DIY project consisting of 1,000 analog reverse-avalanche oscillators, each built
with a transistor, capacitor, and resistor. A singe opamp isolates and amplifies
the output of each unit. In his video Mr. Battle explains the project, runs
through the tune-up procedure, and exhibits the final result. According to the story,
only 1.2 A is used from a 12 V DC supply for the entire setup. There are
10 independently tuned oscillators on each rack-mountable panel. A
printed PCB panel (not including components) can be purchased for $52.
Bob Pease would have loved
this guy whose motivation is summarized thusly: "I like the tangibility of analog.
I hate working on computers. I just can't stand looking at screens. I like standing
up and moving around and making things in a physical world."
Since 1996, ISOTEC has designed, developed
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