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4 of the October 2021 homepage
archives.
Thursday the 14th
This is the second of a two-part series on
the move of the
WWV transmitter stations operated by the National Bureau of Standards (now called
National Institute of Standards and Technology) from Greenbelt, Maryland, to Boulder,
Colorado. WWV Part I appeared in the January 1967 edition of the ARRL's QST
magazine. WWV began transmitting time / frequency standards in 1920 in order to
provide a means for remote stations and laboratories to calibrate local standards
that would prevent transmitting stations from interfering with each other. Although
most people don't realize it, the 60 kHz signal that their 'atomic' clocks
and watches use to self-adjust time emanates from the WWVB antenna in Boulder. The
first installment of the article discusses the history and rationale for relocating
the WWV facility to a new location...
As is typical for Gary Breed, editor of
High Frequency Electronics magazine, he wrote a great general interest
article about the time and frequency broadcasts put out by the National Institute
of Standards and Technology (NIST) – originally National Bureau of Standards (NBS).
His piece concerned the history of the WWV and WWVH signals that have been used
since their origin in 1920 by amateur and professional radio operators to calibrate
and synchronize time and frequency standards. I highly recommend reading the one-page
article. There is yet another standard signal that is broadcast continually from
the NIST site in Boulder, Colorado, that just about everyone is familiar with whether
they know it or not. That would be the
WWVB signal used by
all of the "radio-controlled" or "atomic" clocks...
"Most Next-generation wireless systems are
based on
beamforming networks (BFNs). These systems are complex, expensive and require
multiple circuit layers for implementation. Scientists at the Tokyo Institute of
Technology and the European Space Agency have now introduced a novel matrix topology
for a BFN that reduces the number of layers BFNs typically need. This paves the
way for cheaper and more efficient next-generation wireless systems. Wireless technology
is responsible for enabling pivotal innovations such as radio and satellite communication.
Central to these systems are antennas that can transmit and receive signals. As
the scope of wireless technology continues to grow, the next generation of wireless
systems require multibeam antennas that are capable of efficiently handling multiple
beams...
While on the LinkedIn website I happen to
see a post by NuWaves Engineering
announcing multiple job opportunities for engineers, technicians, and managers.
Per their Careers webpage; "A veteran-owned small business founded in 2000. NuWaves
is a premier supplier of RF and microwave solutions for aerospace and defense customers.
NuWaves provides quick-tempo design and engineering services, from HF through Ku-band,
that address the most demanding customer requirements, such as electronics hardware
miniaturization, project cost, and schedule. NuWaves offers a competitive benefits
package that rivals or exceeds what larger companies can provide..." Please mention
you saw this on RF Cafe (no, I'm not getting paid for it).
Here is a vintage crossword puzzle from
the October 1957 edition of Popular Electronics magazine. Being created at a time
solidly into the semiconductor era, you do not need a knowledge of vacuum tube terminology.
This one contains mostly words relating to electronics similar to the weekly electronics,
math, science, technology, and RF & microwave theme crosswords from RF Cafe.
It won't take you too long to complete...
Analog Devices (ADI) will host "Tech Day: RF &
Microwave" on Thursday, October 14th, from 11:00 AM to 1:00 PM Eastern Time.
Of course the focus will be on Analog Devices' products and their contributions
to end item products of their customers. Although these types of events are essentially
high-tech infomercials, the presenters are usually the company's top applications
engineering people and often the device designer is there to pitch the part and
answer question. Topics include X-band direct RF sampling, instrument grade signal
fidelity at mm-wave frequencies, X- and Ku-band radar development...
Holy
guacamole! I saw in Home Depot last night that the price of a 250-foot roll of
12/2 Romex cable now costs more than $150!!! Just a few months ago it was under
$70. Last year I bought a 250' roll of
10-3 Romex for $140; today it costs >$400. Prices of both copper and plastic
have skyrocketed since summer. The plastic electrical box aisle has been nearly
empty for many months - it looks like the toilet paper aisle in the grocery stores
did at the beginning of the Wuhan Flu plandemic. Gas prices here in PA are up nearly
50%, and food is getting outrageous. Folks, we are getting screwed big-time by politicians
causing all this turmoil worldwide. I'm not sure what their end game is, but things
are not looking good. Unlimited immigration burdening supplies and resources, shutting
down domestic energy production, stranding container ships offshore, etc. How far
will this social engineering and
cost of living escalation go? I am feeling the pain. Evidently "We the People"
have no control over it anymore.
It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™.
This is an equivalent of the extensive set of amplifier, mixer, filter, switch,
connector, waveguide, digital, analog, antenna, and other commonly used symbols
for system block diagrams and schematics created for Visio™. Each of the 1,000 or
so symbols was exported individually from Visio in the EMF file format, then imported
into Word on a Drawing Canvas. The EMF format allows an image to be scaled up or
down without becoming pixelated, so all the shapes can be resized in a document
and still look good. The imported symbols can also be UnGrouped into their original
constituent parts for editing. Check them out!
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.
Wednesday the 13th
ARRL's Annual Online Auction is running
October 8-14 this year. I somehow missed posting a notice earlier, but there's still
more than a day left to get in on it - both for buying and for selling. Many items
have 10 or more bids on them, so you had better act quickly if you are looking for
something in particular. There are also many "ARRL
Lab Mystery Junque Box" listings for the gamblers out there. Probably a lot
of people are willing to bid on them figuring if nothing else they are helping to
support the ARRL. Happy hunting.
ConductRF announces availability of professional
high frequency
TSA89 series of RF test cables with performance to 40 GHz.
Precision connector choices include; SMA, Type-N, 3.5mm, 2.92mm, & 2.4mm. Key
features: High-frequency point to point cable, light weight rugged double-shielded,
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. 100% factory VSWR and insertion loss tested. Wide selection
of configurations & lengths. Cables are in stock and available immediately from
Digi-Key...
Mr. Steven Seiden published an very
usefule article on the Electronic Design website entitled
The 6 Best Practices for Developing Successful Test Engineering Solutions. He
begins: "Learn the six best practices to follow to help you develop successful automated
test solutions faster and at lower cost. Many companies choose a solution because
the initial capital outlay on the system appears acceptable; however other important
key cost drivers should be considered. These include: Set-up costs: These are the
costs associated with taking the hardware, integrating it into a mechanical enclosure,
wiring the system, building the test fixtures, checking that the software drivers
are compatible, and developing the software code to provide a suitable application.
Reducing set-up costs and risks can be done by finding a suitable single supply
resource partner who has domain and industry knowledge across multi-vendor solutions.
Overheads: Recruiting and training staff to develop a successful solution can add
considerably..."
4 tubes and sockets, 12 capacitors, 7 resistors,
4 inductors, 3 transformers, a crystal, a meter movement, a switch , a bulb, 3 jacks
(for a tuning meter), a project box, a handle and and little hookup wire and solder.
That's all it used to take to construct a home brew
dual band (5- and 10-meters) amateur radio transmitter as featured in the February
1941 edition of QST. You can probably find all the parts at a Hamfest to make one
today, but you will need to modify the 5-meter band circuit to current 6-meter band
operation since there is no 5-meter band anymore (lost to VHF television)...
As we approach the snow season, this info
might prove useful to you. When I was young, I loved
snow for many reasons. Perhaps
the biggest reason I loved snow was that it created the potential for getting a
day off of school. Of course, sledding, building snow men, snowball fights, and
just watching the snow fall were great pastimes, especially if done while enjoying
a day off school. Unfortunately, where I grew up in Annapolis, Maryland, there was
never enough snow for my liking. I recall vividly laying in bed on a school morning
listening to the AM radio hoping to hear a report of a school closing. Usually,
it would be raining at my house while the announcer would report that kids at schools
in the northern and western counties would be off for the day. Only my parents were
happy about that. Later in life, I still enjoy the snow...
Each edition of Radio-Electronics
magazine featured a couple pages of industry news entitled "The Radio Month." This
August 1949 issue started out with a rather tragic items reporting on the death
of Philco chairman John Ballantyne evidently while making a speech at his 13-year-old
son's school commencement ceremony. It's hard to imagine the scenario. Also included
was news of one of the first attempts in the country to impose training and licensing
mandates on electronics repairmen. Illinois and New York led the effort. Fortunately,
the attempted legislation did not succeed. The
Federal Communications Commission (FCC) marked it 15th year of existence as
a federal bureaucracy after it replaced the former Federal Radio Commission (FRC)
in 1934...
RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. Chances are you
have never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system
cascade parameter and frequency planner that includes filters and mixers for a mere
$45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch
and the format is entirely customizable. It is significantly easier and faster than
using a multi-thousand dollar simulator when a high level system analysis is all
that is needed. An intro video takes you through the main features...
Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
Tuesday the 12th
During World War II, Germany terrorized
Europe with it
rocket bombs, most notably the V-1 Buzz Bomb and the V-2 Rocket. The "V" prefix,
BTW, stands for Vergeltungswaffe, translated as "vengeance weapon," or "retribution
weapon." Both "vengeance" and "retribution" are really misnomers since it was Germany
that was the aggressor in both WWI and WWII. The vengeance or retribution in Hitler's
view was likely the punishment and restrictions imposed on Germany by the Treaty
of Versailles for its vicious and inhumane behavior before and during World War I.
History shows they doubled down on it during World War II. But I digress. This
1946 article in Radio-Craft magazine proposes a scheme for a "radar rocket"
system that could detect, acquire, and intercept an enemy rocket bomb in flight
- a concept that was never really successful until the Patriot Missile...
"On the cover of the
Pink Floyd album Dark Side of the Moon, a prism splits a ray of light into all
the colors of the rainbow. This multicolored medley, which owes its emergence to
the fact that light travels as a wave, is almost always hiding in plain sight; a
prism simply reveals that it was there. For instance, sunlight is a mixture of many
different colors of light, each bobbing up and down with their own characteristic
frequency. But taken together the colors merge into a uniform yellowish glow. A
prism, or something like it, can also undo this splitting, mixing a rainbow back
into a single beam. Back in the late 1970s, scientists figured out how to generate
many colors of light, evenly spaced in frequency, and mix them together - a creation
that became known as a frequency comb because of the spiky way the frequencies..."
"He no sooner gets alone with a sweater
girl than he's trying to pull the wool over her eyes." That's a really old joke
that only old guys like me remember. "Sweater Girl" was a term
used to describe... how to properly put it... um, you know, the Dolly Parton types...
those who have a good singing voice . While that is not the
purpose of a sweater girl overtly used in this article from a 1944 edition of
Radio-Craft, you can bet the authors intended the term as an eye-catcher.
I thought you might need to be apprised of the origin of the term to appreciate
the title. You're welcome...
Engineering Your Career (Part 3):
Professional Societies and Community Groups, compliments of the Machine
Design website, is now available. Per Tricia Hatley: "Professional societies
and community groups can help build networks of design professionals that help engineers
stay technically relevant. Engineers who invest time and energy in professional
associations and community groups will quickly find that those investments pay dividends
in terms of building networks of engineers and design professionals and staying
technically relevant. Both of these can be critical to an engineer’s career success.
Investing in Your Profession and Community When you join a professional association
or a community group, you've taken an important first step in boosting your career.
But that membership likely won't pay dividends until you engage..."
I finally managed to get an early edition
of The
Wireless World magazine for a reasonable price on a eBay auction. Now I
will be able to post a few of those articles from the UK to compliment those from
some of the American magazines. This particular edition is from March 9th, 1932.
My next target is to get a few from the World War II era which although it began
on December 7, 1941 from America's perspective, it officially began on September
1, 1939 for Europe. Warning for the weak of heart - epochal words like "niggardly"
and "parsimonious" are used herein, and therefore adult supervision should be employed
if ignorance might cause an objection to at least one of the aforementioned...
RF Cafe's raison d'être is and always has
been to provide useful, quality content for engineers, technicians, engineering
managers, students, and hobbyists. Part of that mission is offering to post applicable
job openings. HR department employees and/or managers of hiring companies are welcome
to submit opportunities for posting at no charge (of course a gratuity will be graciously
accepted). 3rd party recruiters and temp agencies are not included so as to assure
a high quality of listings. Please read through the easy procedure to benefit from
RF Cafe's high quality visitors ...
Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
procedures.
Monday the 11th
![Geomagnetic Storm October 11, 2021 - RF Cafe](images2/geomagnetic-storm-october-11-2021-hp.gif) "A
massive solar flare is due to hit Earth today, authorities are warning - potentially
disrupting power grids and bringing the Northern Lights as far south as New York.
The flare - officially known as a coronal mass ejection (CME) - was observed on
Saturday on the side of the sun directly facing our planet and comes as we enter
a period of increased solar activity. An alert was published by the US National
Oceanic and Atmospheric Administration (NOAA) which warned the geomagnetic storm
could cause power grid fluctuations with voltage alarms at higher latitudes, where
the Earth is more exposed."
The
Crosley Model 567 "Chairside" chassis was an out-of-the-box concept in the day
when nearly all radios were of the familiar tabletop or floor console variety. At
least for now, I am going to only scan and post Radio Service Data Sheets like this
one featuring the Crosley Fiver Chassis "Chairside" Model 567 radio in graphical
format, rather than run OCR on them to separate the textual content. There are still
many people who restore and service these vintage radios, and often it can be difficult
or impossible to find schematics and/or tuning information. I will keep a running
list of all data sheets to facilitate a search...
"The electrical properties of a carbon fibre
are very different when measured across its width or along its length, according
to a new study by Satoshi Matsuo and Nancy Sottos at the University of Illinois
at Urbana-Champaign in the US. Using a technique designed to probe the electrical
resistivity of 2D materials, the duo has showed for the first time that
fibres are significantly less conductive in the transverse direction. When carbon
fibres are woven into interlocking sheets, the composite materials they produce
can display a unique variety of electrical properties, with applications including
electromagnetic shielding; sensing for structural damage in buildings; and protection
against lightning strikes. To tailor these composites for specific uses, it is important
to have accurate models of their electrical behaviours..."
Regarding the testing of autonomous vehicles
in public roadways, Colin Barnden in an EE Times website article emphatically
states: "I loathe statistical
averages because they are misleading. ...what really makes me furious is hearing
AV executives spouting the '94 percent human error' garbage. I am clearly not alone
in my concerns about the AV industry demonstrating a loose relationship with hard
facts. Writing on Twitter on October 4, Jennifer Homendy, Chair of the National
Transportation Safety Board (NTSB) wrote: 'Stop with the 94%!' followed by a link
to a blog piece entitled 'The 94% Error: We Need to Understand the True Cause of
Crashes.' Dissemination of the dodgy statistic is common and was even spoken by..."
It was just before Christmas in 1948 that
Bell Telephone Laboratories announced the
invention of the transistor by Messrs. Bardeen, Shockley, and Brattain. Though
constructed of a slab of germanium and a flimsy point contact of wire, it represented
for the first time the use of a semiconductor which exhibited signal gain. The technical
gauntlet had been thrown down for manufacturers worldwide to develop improved versions
with higher gain, wider operating frequency, greater current and voltage handling,
more robustness and higher power handling, while shrinking the physical size of
bare die and packaging, and lowering costs... and doing it all without infringing
on the blitzkrieg of patents being filed in scores of countries. This self-promotion
in a 1952 issue of Radio & Television News magazine...
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 16,000 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. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
ASC designs and manufactures hybrid, surface
mount flange, open carrier and connectorized amplifiers for low, medium and high
power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon
(Si) transistor technologies. ASC's thick film designs operate in the frequency
range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up
to 20 GHz.
Sunday the 10th
Coming to a country near you? "Lebanon's
electricity network collapsed on Saturday after the two most important power
stations ran out of fuel, leaving private generators as the only source of power.
The state-owned electricity company has been providing citizens with just a few
hours of power a day for months, but the total collapse of the national grid will
compound the misery of those who can’t afford to run generators and had relied on
those few hours. The outage marks the latest milestone in the unraveling of Lebanon,
which is undergoing what the World Bank has described as one of the world’s three
biggest financial collapses of the past 150 years..."
Werbel Microwave is a manufacturer of RF
directional and bidirectional couplers (6 dB to 30 dB) and RF power dividers
/ combiners (2- to 16-way) with select models operating up to 18 GHz and 100 W
of CW power (3 kW peak). All are RoHS and REACH compliant and are designed and manufactured
in our Whippany, NJ, location. Custom products and private label service available.
Please take a couple minutes to visit their website and see how Werbel Microwave
can help you today.
This
Technical Themed Crossword Puzzle for October 10th has many words and clues
related to... you guessed it... engineering - including RF, microwave, optics, mathematics,
chemistry, physics, and other technical subjects. As always, this crossword puzzle
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 8th
These "Radio
Term Illustrated" and "Technical Term Illustrated" electronics-themed comics
are amongst the best I can remember seeing. They appeared in two 1946 issues of
Radio-Craft magazine. For the uninitiated, WAVES is an acronym for Women Accepted
for Volunteer Emergency Service. They were a World War II phenomenon established
on July 30, 1942, half a year after the Pearl Harbor attack. Their Navy Reserve
status granted both commissioned officers and enlisted women official service duty
status for the duration of the war and entitled them to the privileges (and in some
case dangers) that came with it. As with women occupying manufacturing and even
airplane ferrying jobs previous dominated by men, WAVES freed up men to go fight
the war. The artist, Frank Beaven (FB), solicited suggestions from readers and then
turned them into a sort of double entendre form of comics...
![Iowa Hills Software Logo - RF Cafe](../../factoids/images2/Iowa-Hills-Software.gif) Über RF/microwave engineer and Ham radio
aficionado Cornell D. sent me an e-mail about a website called Iowa Hills Software.
Per the site's tag line, "The
analog and
digital filter design programs on this site are FREE. This web site, and the
programs on it, are a retired RF engineer's winter time hobby." If your primary
interest is in calculating theoretical values for filters and not being able to
simulate "real world" effects of component geometry and materials, packaging, and
circuit boards, then it would be hard to find a more comprehensive program for investigating
the potential for filter designs. However, the software goes beyond presenting only
the canonical form (basic) of the circuits because, particularly for bandpass and
bandstop filters, it is often difficult or impossible to realize with actual components.
To wit: "The canonical form, or simplest form, is described in most textbooks, but
is almost useless in practice..."
"The next generation of embedded MRAM (magneto-resistive
RAM) may boil down to changing the order of ingredients in the recipe.
Spin-orbit-torque
(SOT) MRAM addresses the 'trilemma' that Spin-transfer torque (STT) MRAM currently
faces, said Antaios CEO Jean-Pierre Nozières in an interview with EE Times.
The significant voltage across the device tunnel oxide that's required for writing
means there is a continual tradeoff between data retention, write endurance, and
write speed. That means even though it's reached near maturity, STT MRAM is still
constrained when it comes to meeting the demands of high-speed RAM applications
that require a combination of high speed and infinite endurance, along with acceptable
data retention..."
Axiom Test Equipment, an electronic test
equipment rental and sales company has published a new blog entitled "Choose
the Best Chamber for Your Next Project" that informs people about the use of
environmental chambers for many testing applications. Temperature and humidity environmental
test chambers are able to provide rapid product temperature change rates and use
varying levels of relative humidity to locate design problems prior to shipping
your products, improving product quality and reliability. Axiom stocks models for
sale or lease from a number of leading manufacturers, such as Temptronic, Tenney,
Thermonics, and Test Equity. We have small benchtop size chambers up to larger reach-in
chambers...
The fundamentals of
Class-B push-pull amplifiers have not changed since 1960 when this article appeared
in Electronics World magazine. The transistors for making them have improved
in most cases, but the design procedures are basically the same. Class-B amplifiers,
in case you are not familiar with the topology, are able to amplify zero-referenced
sinusoidal signals throughout the full 360 degrees of rotation signals without an
offset voltage bias; they are constructed from two Class-A amplifiers in a cascode
configuration. Issues like crossover distortion and thermal runaway are discussed
in the amplifier design procedure...
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.
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.
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