Today in Science History -
I suppose a more appropriate title for this chart
would be "Foreign
Valve Substitution Data," considering that most (if not all) of Europeans refer(red)
to vacuum tubes as "valves." As with having posted scores of Radio Service Data Sheet
pages for the benefit of hobbyists who restore and service vintage radio equipment, I
also post other hard-to-find reference resources when I find them. Sure, the number of
people looking for this information is extremely small, but they are extremely grateful
for this when in the throes of finding replacement tubes (valves). Posting a hyperlink
to this page on the RF Cafe homepage will assure that ...
Barry Rimer (WA2WAO), proprietor of Corner Press,
has been printing
QSL cards since 1961. QSL cards are cards Amateur Radio Operators (HAMS) send to
each other to confirm a QSO (talking to each other on the air). QSL's were our first
product; it's how we started in 1961. In 1971 we changed the company name to Corner Press
to reflect a more diverse product line, not just HAM radio specific. There are more than
70 standard designs to choose from, or submit your own custom design. We produce QSL's
in many styles: Flat printed in one or two spot colors, Raised printed in one or two
spot colors, Full bleed full color. Please contact Barry for your QSO printing needs ...
"The 10 steps of the engineering design process
are fundamental knowledge for all budding engineers. If you're hoping to become an engineer,
one of the most crucial things you need to learn are the 10 steps of the
engineering design process. This process lays out the correct protocol
for any project, allowing everything to go seamlessly. No matter which area of engineering
you intend to work in, the 10 steps will always be important. They're a fundamental part
of engineering, and can always provide a solid foundation for your work. Let's take a
look at each step, and hear what the experts have to say about the importance ..."
At least 10 clues with an asterisk (*)
technology-themed crossword puzzle are pulled from this past week's (7/16 - 7/20)
"Tech Industry Headlines" column on the RF Cafe homepage. For the sake of all the avid
cruciverbalists amongst us, each week I create a new technology-themed crossword puzzle
using only words from my custom-created list related to engineering, science, mathematics,
chemistry, physics, astronomy, etc. 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, see someone or something in the exclusion list who or that is directly related
to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll ...
Here is the 46th quiz I have posted from 1960s
and 1970s issues of Electronics World and Popular Electronics magazines.
Most of were created by Robert P. Balin. I like to save them for Friday afternoons.
Guys like me who cut our teeth on analog meters read these indications like a second
language. Even novices usually do a good job on the meter needles, but reading a mechanical
micrometer (#9) might be more of a challenge, especially if you have never used one before.
The same goes for a dial caliper. Can you read the dials on a mechanical gas or electric
meter, where some spin CW and others spin ...
Fairview Microwave, a leading provider of on-demand
RF and microwave components, has released a new line of 40 GHz
skew-matched cable pairs designed for bit-error-rate testing, eye diagrams and differential
signals at data rates of 10 Gbps to 28 Gbps. Fairview's new line of skew matched
cables consists of three extremely flexible models that are 100% tested for skew match.
Performance specs include an impressive VSWR of 1.4:1 and 1 ps delay match. These
cable pairs cover two channels with 50 Ohms nominal impedance and a bandwidth of
DC to 40 GHz. The skew matched cables ...
"Test engineering is a global endeavor. Electronic
devices can be prototyped thousands of miles from where they are manufactured and ultimately
deployed. They must be tested every step of the way. But electrical engineers worlds
apart may store test results in different places, which can complicate tasks like debugging
glitches and correlating results with test conditions. Santa Clara, California-based
startup Gradient One is trying to simplify many of the mundane tasks weighing down test
engineering as hardware becomes more complicated. The company has developed a cloud platform
for test automation, storage and analysis and other tasks that traditionally have been
This feature appeared at the end of a larger article
titled, "RF Induction Heating." A notable difference between the type of induction heating
in the other article and the type described here is that rather than directly heating
a metallic substance to be treated (melted, bent, tempered, etc.), a "susceptor"
(graphite crucible) is used to absorb the field and heat up to melt by conduction (via
a quartz liner) the silicon material within. Pure silicon cannot absorb the RF energy
sufficiently to be heated directly. Interestingly, if you go to the Wikipedia susceptor
page, it has an image of Hot Pockets, which are wrapped in a type of susceptor that produces
a crispy exterior while heating the interior. As you are probably aware ...
"The defense department's research wing is pouring
$1.5B into projects that could radically alter how electronics are made. The U.S. Defense
Advanced Research Projects Agency is launching a huge expansion of its Electronics Resurgence
Initiative, boosting the program to US $1.5B over five years. And while some of the research
efforts will be just what you've come to expect from the agency that brought you disposable
drones, self-driving cars, and cameras that can see around corners, a lot of this new
money is going toward ideas that could fundamentally change how chips are designed. If
it all works out ..."
"Mini-Circuits is pleased to announce a new partnership
with 3D imaging sensor company Vayyar Imaging to offer
microwave transceiver project kits with broad applicability for students and university
programs spanning topics in electromagnetic theory, RF / microwave engineering, RF systems,
and radar technology. The first project kit, UVNA-63 includes all the elements students
need to build a fully functioning vector network analyzer, develop S-Parameter algorithms,
and perform real-time measurements of 2-port RF devices. The kit comprises Vayyar's high-performance
transceiver chip ..."
Hint: It's not, as is often claimed, in honor of
Kilby (he designed the first commercial IC). Last night while reading
an article on T, RS, and JK flip-flop RTL (resistor-transistor
logic) ICs, I tried to recall the origin of the "JK" designation. An Internet search
turned up lots of claims of Jack Kirby, but fortunately
posted the true origin in a piece on the Quora website. The origin predates the fame
of Jack Kilby, and is remarkably uninteresting. This is another case of a fake story
being perpetuated merely because it seems reasonable. I saved a copy of Mr. Bhattacharya's
post in case it one day disappears ...
If you are interested in the ingenious machines
and methods manufacturing engineers dream up for quickly and reliably producing parts
and assemblies in large volumes, then you will definitely appreciate this article on
RF induction heating. This process of course only works with metallic objects, unlike
microwave type heating schemes that work with liquids. Induction heating requires the
generated electric, magnetic, or RF field to invoke electrical currents within the metals
to increase its temperature. Ohm's law applies here. Have you ever used a torch to heat
a metal bolt, wire, car fender, etc., and noticed how it usually discolors the surface
and might even produce a crusty oxide layer? An extreme temperature rise as is required
for soldering, brazing ...
Anatech Electronics, Inc. offers the industry's largest portfolio
of high-performance standard and customized RF and microwave filters and filter-related
products for military, commercial, aerospace and defense, and industrial applications
up to 40 GHz. Anatech has introduced three new filter designs: a 1090/60 MHz cavity
bandpass filter with N-type connectors, a 150/10 MHz cavity bandstop filter with SMA
connectors, and a 2250/100 MHz user-tunable bandpass filter with SMA connectors ...
Kendall Castor-Perry has posted Part 2 of
"The Chronicles of GND" on the Electronic Design website. "The Filter
Wizard's latest installment of 'The Front End' looks at how the ancestral 'split-supply'
PCB layouts have mostly ceded to 'single-supply' configurations, and the GND implications
that often ensue. When I get a printed-circuit-board (PCB) layout back for review, there
are a few things I look for first. I can usually get a feeling for what kind of board
designer has been at work, too, specifically if s/he is (or s/he thinks s/he is) a 'digital'
designer, an 'RF' designer, or a 'power' designer. You might ..."
IEEE MTT-S 2018 International Microwave Symposium (IMS), took place
in Philadelphia this year from 10-15 of June. The event marked an attendance of over
8,400 attendees. IMS, the annual conference and exhibition of the IEEE Microwave Theory
and Techniques Society (MTT-S), is the premier international meeting for technologists
involved in all aspects of microwave theory and practice. The six-day event, held at
the Pennsylvania Convention Center, drew 4,500 attendees to the technical program and
the exhibition featured over 625 exhibiting companies. IMS attendees comprised RF designers,
researchers, developers, and academics ..."
"Researchers at ETH Zurich in Switzerland claim
the fastest quaternary-base
double heterojunction bipolar transistor (DHBT) reported to date
with maximum oscillation greater than the cut-off frequency, grown by metal-organic chemical
vapor deposition (MOCVD). The quaternary base consisted of graded gallium indium arsenide
antimonide (GaInAsSb). Adding indium to GaAsSb improves electron transport properties
such as mobility and sheet resistance. GaAsSb's conduction band has two types of valley
- one at zero wavevector (the Γ point) and one in the 'L' directions of the crystal structure.
In GaAsSb, the L-valley is close ..."
In 1967, when this parody was published in
Popular Electronics, the Iron Curtain of Communist Russia and the Union of Soviet
Socialist Republic (USSR) was still firmly in place. Constructing faux
Russian-sounding words was common at the time. All a comedian needed to do to have
their audiences rolling in the aisles was to append "ski," "ovitch" or "skov" to the
end of any word, or add lots of "z"s and "k"s in the middle of words. Tim Conway and
Harvey Korman did many hilarious skits on the 1970s' Carol Burnett show where they feigned
speaking in German, Japanese, Russian, and other tongues. Nowadays ...
RF Cafe's continued existence depends on companies
like ERZIA providing support. ERZIA produces microwave and mm-wave modular amplifiers and integrated assemblies
operating from Low frequencies up to 100 GHz. Their catalogue of standard amplifier
modules comprises more than 100 different models, having also a high capacity of customization
for amplifiers and integrated assemblies. Some of products have space heritage and are
used in aerospace, commercial, military and scientific systems, having a wide range of
final applications ...
With more than 780 custom-built symbols,
this has got to be the most comprehensive set of
Visio Stencils available
for RF, analog, and digital system and schematic drawings! Every object has been built
from scratch to fit proportionally on the provided A- and B-size drawing page templates
(you can use your own page if preferred). Components are
provided for equipment racks (EIA and ETSI) and test equipment,
system block diagrams and conceptual drawings, and for schematics
World leading microwave engineering company Flann
Microwave is supplying vital components to the U.S. space agency NASA for a major spaceflight
mission making the first-ever global survey of Earth's surface water. The multinational
Water and Ocean Topology (SWOT) satellite, planned to launch in 2021, is being jointly
developed and managed by NASA, the French Space Agency (CNES), and the Canadian Space
Agency, with contributions from the United Kingdom Space Agency. It is UK-based Flann's
first project for NASA and has seen engineers working closely with their counterparts
at NASA's Jet Propulsion Laboratory (JPL) ...
"If you want to remain at the top of your game,
trade show attendance should be part of every engineer's strategy
for growth and continuing education. In this age, you can find out everything you want
to know about anything with just a few keystrokes. There are processes, materials, components,
and modules for which you can get nearly instantaneous data of all types (pricing, availability,
specification, reviews, etc.) via simple online searches. The problem is you have to
know what you are searching for. The Internet is a true wonder for researching when you
know what you are looking for ..."
Mac's staff service technician, Barney, asked
a great question when he mentioned that Pittsburgh radio station KDKA made the country's
first commercial broadcast in 1920: "Who
was listening?" It is a reasonable question since prior to the beginning on commercial
radio broadcasts there would have been no reason for there to have been a lot of people
to own a radio for receiving commercial broadcasts. The answer, of course, is that there
were plenty of multi-band radios in homes and businesses for listening in on shortwave
broadcast from around the world - a very popular pastime in the era. Just as today we
are bombarded with admonitions to not stare at computer monitors or cellphone screens
for too long lest we suffer near-sightedness or worse, radio listeners of yore who used
headsets were told, "Youths of this generation will never have as protruding ears ...
Beginning on page 22 of the June 2018 issue of
High Frequency Electronics (HFE). "A Non-Linear Analysis of the Saturated MOSFET," by Dr. Alfred
Grayzel. "Abstract: The maximum power and the maximum efficiency at the maximum power
have been derived for the MOSFET; when the MOSFET is in saturation over the entire cycle,
using the square law theory. Results are presented for the following three cases: the
gate voltage is a sinusoid, a half sinusoid and a square wave. Results using the square
law theory and bulk-charge theory for analysis of the MOSFET are compared ..."
ZipRecruiter is a relative newcomer to the online
job search world. It began in 2010 as a "kitchen table project" by the founders literally
in the kitchen of co-founder Ian Siegel. I hear their radio ads frequently. You might
have seen ZipRecruiter ads on TV, but I almost never watch TV. The BBB gives ZipRecruiter
an A+ rating. If you scan through the user gripes, they appear to be mainly from hiring
companies who did not read and/or adhere to the policy for cancellation of the service.
Job seeker complaints tend to focus on dissatisfaction with hiring company practices,
which you will find with any job posting service. For comparison, Monster gets a D- rating,
and CareerBuilder rates an A+. Having no personal experience with ZipRecruiter, I can
neither endorse nor condemn them. Marketing Intern Amanda Drury sent me an e-mail asking ...
I recently created a new reference page titled
"Resistivity (ρ) & Conductivity (σ)
of Metals, Alloys, Rocks, and Soils." Values for materials are pulled from my copy
of Reference Data for Radio Engineers, Sams Publishing. Resistivity, also referred
to as specific resistance, is dependent on the nature of the material as well as its
volume definition (shape and size). Resistivity is expressed in units that are the product
of resistance and length; e.g., Ω·cm. As an example of calculating a volume's resistance,
consider the drawing to the left. Assume 12 AWG copper wire with a resistivity of 1.72x10-6 Ω·cm,
a cross-sectional area (A) of 0.03309 cm2, and a length ...
ConductRF is offering standard
D38999 RF coaxial cable assembly
configurations with RF Contacts including; BMA to 20 GHz SMPM to 60 GHz Size
#8 to 18 GHz Size #12 Mil-Spec. Size #16 Mil-Spec. Cable choice include Low Loss
Flexible and standard RG styles. Custom marking and also ruggedization coverings including
Nomex weave available ...