Glass-encapsulated bi-reed magnetic switches
were a relatively recent invention that came out of Bell Labs when this
Carl & Jerry episode was published in 1962. It seems like
such simple and common components have been around forever, and they have for a
growing portion of people in the electronics realm since that was more than half
a century ago. As is often the case with John Frye's enterprising pair of teenage
experimenters, the reader is treated to a tutorial on the operational theory of
the switch, with its dependence on magnetization by induction. The story ends up
being quite humorous, and reminds me a bit of the old All in the Family
episode where a window salesman uses a photography light measuring meter to convince
Archie he is actually detecting severe air drafts
...
It has been quite a while since I looked through
TradePub's list of white papers. For along time there had not been many relevant
topics that struck me as useful enough to pitch to RF Cafe visitors. The ones listed
here are a small sample of a lot of new papers, articles, and booklets available.
You might want to take a couple minutes to see what's new there. They are all free
downloads.
Crossword puzzles have probably lost their
appeal to most people. I suspect so because up until early this year, I created
a custom
electronics-themed crossword puzzle every week for RF Cafe visitors,
but not a single person has written to ask that they be continued. Oh well, that
saves an hour every Sunday. Lots of magazines used to print crossword puzzles based
on their readers' interests. Unlike the RF Cafe crosswords that use only relevant
words, those puzzles used common filler words where it was too hard to find a thematic
word. This crossword puzzle from a 1965 edition of
Electronics World does a pretty good job of using a
...
$15.1 billion is a lot of money both today
and in 1963, when this story was written. That was the value of the electronics
market at the time. According to the Bureau of Labor Statistics' Inflation Calculator,
$15.1B in 1963 is the equivalent of $116B in 2014. The Consumer Electronics Association
projects a 2015
electronics gadget market value of $223B, which does not include
military, medical, and industrial electronics. The World Semiconductor Trade Statistics
group predicts a $333B semi market value for 2014. Apple alone just hit the $700B
market cap benchmark - that's just one electronics company. By any measure, electronics
has enjoyed a continual, significant gain since the early 20th
...
Unless you live with or interact regularly
with someone who is
blind, it is easy to forget the difficulty everyday life poses
for him or her. I do not know any blind people. A lot of effort has been put forth
to help facilitate those who are severely sight impaired or totally blind. Helen
Keller is probably the most well-known blind person, but I think of Ray Charles
when the subject arises. Melanie and I visited the Florida School for the Deaf and
Blind while in St. Augustine a few years ago, where we learned Mr. Charles
was fortunate to have attended as a child. His rendition of "America the Beautiful"
is by far my favorite. This article from a 1935 edition of Short-Wave Craft
reports on efforts to make the electronics trade accessible to blind people via,
in this case, pseudo-Braille versions of schematics. Although theoretical design
and analysis activities were possible, the potentially lethal voltages present in
...
Empower-RF-Systems-Conducting-Live-Demos-EMC-SI-2-13-2015.htm" >
Empower RF Systems is once again conducting live
demonstrations of broadband, high power amplifiers with compelling performance,
industry leading small size, and user interface / functionality that dares to challenge
legacy products offered in the market. Next appearing at
EMC & SI 2015 in Santa Clara, we will be showcasing our
1 to 3 GHz, 1 kW HPA in a 5U chassis - an extraordinary design and great
addition to the growing product family of next generation platforms from Empower.
Please stop by
Booth 711 to see us.
The Douglas DC-3 revolutionized commercial
air travel with its introduction in 1935, and the military version, the C-47 Skytrain
(aka Dakota), proved an invaluable workhorse for the
U.S. Army Air Force during World War II. Without reliable and effective
radio communications, the aircraft's success would have been much less. Companies
like
Bendix Radio led the way with rugged avionics that could take
the harsh conditions of flight that include vibration, shock, pressure changes,
and temperature variations. Replacement parts were usually not conveniently on-hand
and the radio operator often needed to also be a trained electronics technician
or engineer. "Necessity is the mother of
...
Good, clean humor has always been a welcome
addition to my day whether it come in the form of a printed comic strip, a TV show,
or someone's mouth. My father's side of the family was populated with many jokesters
who could be counted on to deliver an ad hoc pun or zinger at the appropriate moment.
The environment instilled a great appreciation for such entertainment, so these
electronics-themed comics that appeared in editions of Radio-Electronics,
Popular Electronics, et al, are a refreshing distraction from the workaday
world. An old saying claims "laughter is the best medicine," and while it cannot
cure cancer, a good dose of humor often helps ease the pain.
300 W Power Handling
to 12 GHz
RFMW-Florida-RF-Diamond-Termination-300-W-12-GHz-2-11-2015.htm" >
RFMW, Ltd. announces design and sales support
for the CT2010D from EMC Technology. The CT2010D Diamond
Termination offers 300W CW power handling in a chip size
(2.67 x 5.21mm), SMT package. EMC Diamond RF Resistives® offer high performance
in compact packages. EMC's CVD Diamond terminations surpass BeO and AlN terminations
with operation up to 30 GHz. The CT2010D VSWR is specified at 1.30:1 max for
applications to 6 GHz RFMW-Florida-RF-Diamond-Termination-300-W-12-GHz-2-11-2015.htm"
...
'Short waves,' with their ability to support long distance communications
under certain conditions, became a phenomenon in the late 1920s, and a market developed
for converting commercial broadcast receivers to short wave receivers. Magazines
at the time were full of advertisements for the devices. The particulars of short
waves and the way they propagated in the upper atmosphere were not yet well understood
early on. In fact, the government considered transmission frequencies above 1.5
MHz (≤200 meters) so useless that they assigned
those bands to amateur radio operators. The presence of an electrically conductive
layer, known as the ionosphere, was not verified until 1927 by Edward Appleton.
Hams quickly investigated
...
Networks, Mobile
Broadband
From
GSM to LTE-Advanced: An Introduction to Mobile Networks and Mobile Broadband,
by Martin Sauter, contains not only a technical description of the different
wireless systems available today, but also explains the rationale behind the different
mechanisms and implementations; not only the 'how' but also the 'why'. In this way,
the advantages and also limitations of each technology become apparent. Offering
a solid introduction to major global wireless standards and comparisons of the different
wireless technologies and their applications, this edition has been updated to provide
the latest directions and activities in 3GPP standardization up to Release 12, and
VoLTE
...
In celebration
of its 500th month of print,
Astronomy
magazine's March 2015 edition published an extensive collection titled "500 Coolest
Things About Space." If you have ever tried to assimilate a list of even 50
interesting facts on any topic, you can appreciate the effort involved to come up
with 500. I have been a subscriber to Astronomy, on and off, since sometime
around 1980, and generally prefer it to the only other major astronomy-related publication,
Sky & Telescope. Since RF Cafe's audience members are science
...
-
Albert Einstein won the Nobel
Prize in physics for his
discovery of the
photoelectric
effect, not for
his theory of relativity.
- A
nychthemeron
is a period
of 24 consecutive hours.
-
Eugene Shoemaker is the
only
human whose ashes are
on the Moon.
<more>
of Electrical Measure
In
1988, the National Bureau of Standards (NBS) was re-named National Institute of Standards and Technology
(NIST) because a government bureaucrat needed to justify
his/her position and the financing to change all the signs, brochures, and letterhead
would be paid for with OPM (Other People's Money, pronounced
like 'opium'). Regardless of its name, the NBS is charged with establishing,
maintaining, and enforcing standard units of measure for the country, as well as
with coordinating standard units with other countries. It is interesting to read
how standards have changed over the years, and what methods have been suggested
for establishing those standards; e.g., the Ohm (Ω)
could have been based on a foot of copper wire weighing 100 grains, an
...
December 2014 &
January 2015
The Good
Life is a free publication printed in northern Michigan. Along with advertisements
and stories from local interests, every edition is chock full of humorous quips
and jokes. These (mostly) tech-related items are from
the December 2014 and January 2015 editions.
- New Dog Breeds: Bulldog +
Shih tzu = Bullshihtz, a dog
you can never believe what
he tries to tell you
- Law of Nature:
Nature abhors
a vacuum. But not as much
as dogs
do.
- Performance Reviews: Quick
Thinking: Offers plausible
excuses for mistakes.
- Business Signs: On a
Scientist's door:
"Gone
Fission"
<more>
"But his shop is a lone
outpost; in a single generation, the American who built, repaired, and tinkered
with technology has evolved into an entirely new species: the American who prefers
to slip that technology out of his pocket and show off its killer apps. Once, we
were makers. Now most of us are users." - Andy Cohen, long-time
Radio Shack store owner. Radio Shack is in its last days as
it plans to shut down.
Radio was a powerful
propaganda tool and strategic communications means toward the end of World War I,
and certainly in the lead-up to and during the course of World War II. Many
governments, including the United States and most European countries, forbade the
broadcasting of signals by anything other than an entity licensed for commercial
and/or military purposes. Amateur radio broadcasts were prohibited, although at
least here in the U.S. possession of a receiver for listening was still allowed.
Some of the regions controlled by Nazis did not even permit receivers - mainly because
the government did not want citizens listening to anything that could be considered
propaganda. Jamming of broadcast signals from 'Allied' countries was routinely practiced
by Hitler's and Mussolini's tight-fisted controllers. Many citizens were imprisoned
or executed for
...
R/C Tornado Bombs
When the concept
of
radio-refrigerators was presented in a 1933 edition of Radio-News,
it was not quite what has become reality today. At the time, the Radio Electrical
Exposition had recently been held in Madison Square Garden and the world was just
getting used to the miracle of radio waves - and refrigerators for that matter.
Radio-refrigerators never did make their way into the consumer market. Fast-forward
80 years and now we're seeing the advent of radio-refrigerators re-emerge, only
in a completely different format. This time, rather than playing shows from local
commercial broadcast stations, these appliances are communicating with Wi-Fi routers
to allow owners to check on status and contents from remote locations. In other
news, the editors report on a scheme to use a remote-controlled airplane, signaled
by a
Tesla spark gap transmitter, to drop bombs inside tornados in
order to break up and stop their
...
Product Update, February 9
anatech-product-update-2-9-2015.htm" >
Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized anatech-product-update-2-9-2015.htm" >RF
and microwave filters and filter-related products for military, commercial,
aerospace and defense, and industrial applications up to 40 GHz. Anatech has
released three new cavity bandpass filter designs: a 722 MHz BPF, an 836 MHz
BPF, and a 915 MHz BPF. All can be ordered directly through their
AMCrf web store.
and Job Hunting Advice
"It's Just Another Manic Monday,"
so went a popular song from the 1980s (ouch... that long
ago?) by The Bangles. If you're tired of every Monday being like the scenario
in Groundhog Day movie, then maybe it's time to finally think about moving on. You
know there are plenty of people standing ready to offer their finest qualified -
or unqualified - opinions on the best way to go about improving your current situation,
finding a new job, or avoiding screwing up what is at this time a great job. Here
are a few of the most recent articles
...
Technical Challenge
88 K on a P. 27
V of H K. 24 H in a D. Do you remember those kinds of puzzles where you have to
figure out what is being referred to? The first one is 88 Keys on a Piano, the second
27 Varieties of Heinz Ketchup, and the last is 24 Hours in a Day. If you like tackling
such challenges as associating
familiar quantities with their corresponding subjects, then you'll
want to check out the list I created below that all have science and engineering
themes. If this proves to be popular, I'll do another - hopefully including suggestions
from y'all. Good
...
Technical Service
Mark
Johnson, president of Dicing Plus, wrote asking to be added to the
Technical
Consulting Services listing on RF Cafe. I'm glad to oblige. "Dicing Plus
is a solutions based enterprise. Whether it's custom work requiring a design of
experiments or high volume manufacturing our extensive experience will provide a
path to your complete satisfaction. At Dicing Plus we specialize in difficult or
niche applications requiring customized processing and out of the box thinking.
Our engineers have years of experience providing solutions to the semiconductor
and photonics industry. We work with major suppliers to provide custom blades and
consumables to meet stringent product quality. Based in the heart of Silicon Valley
we stand ready to tackle your dicing and singulating needs. No job is too small
or too challenging."
Maybe it
is just my imagination, but the amount of full-page advertisements in the engineering
magazines seems to have reached a crescendo. People write to me and complain about
the amount of banner ads on RF Cafe. Considering it is the advertisers who are the
ones paying to bring the information to you at no cost to you, harboring too much
resentment toward either the publishers or the advertisers is unreasonable. My question
to incessant whiners is how much of their time and money is spent
...
-
Changing the Operating
Frequency of an RF Power
Amplifier Circuit (p22),
D. Vigneri
-
Keysight Technologies:
Reborn, P. Hindle & G. Lerude
-
Cut the Defense Budget? Sure,
No Worries, B. Manz
-
Security Threats in LTE:
Devices, Access, Core
Elements and Services,
R. Kent
<more>
Design Chart
Not
everybody with a high temperature semiconductor application in need of heat dissipation
has access to a thermal management program with a database of available commercial
heat sinks and/or an ability to analyze a custom-made heat sink.
This article contains simple equations, a handy chart, and instructions on how to
use them to figure out what kind of heat sink you need for your project.
About Film Resistors
Metal oxide resistors have
been around since the early 1960s. We take them for granted now, but prior to their
appearance on the market the mainstays of electronics resistance elements were carbon
composition and wirewound resistors. Carbon compound types are very inexpensive
and are acceptable for a wide range of applications, but they have a bad habit of
shifting value over time, particularly when subject to repeated heating and cooling
cycles. Wirewounds (WW) are a good alternative when
cost and physical space are not issues, but WWs can be tricky or even impossible
to use when frequencies get above a few tens of megahertz because of inductance
limitations. Metal film resistors exhibit much better
...
This has been around for
a long time, but it is timeless in its message. I personally added #13 in honor
of Windows 8. : Rumor has it that one year at COMDEX, Bill Gates reportedly
compared
the computer industry with the auto industry and stated: "If GM had kept up
with technology like the computer industry has, we would all be driving twenty-five
dollar cars that got 1000 miles to the gallon." In response to Bill's comments,
General Motors issued a press release stating: "If GM had developed technology
like Microsoft, we would all be driving cars with the following characteristics:
1. For no reason whatsoever your car would crash twice a day
...
Electromechanical Relay
Switches
Pasternack-High-Rel-Electromechanical-Relay-Switches-2-4-2015.htm" >
Pasternack's latest release of
hi-rel RF switches consists of 42 unique designs
which include 38 connectorized models as well as 4 surface-mount devices that boast
a small footprint and lower cost than traditional connectorized packages. A unique
patented design of the actuator and transmission link has been optimized for magnetic
efficiency and mechanical rigidity which guarantees operation up to 10 million life
cycles with excellent repeatability. The rugged MIL-STD-202 qualified construction
of each Pasternack-High-Rel-Electromechanical-Relay-Switches-2-4-2015.htm" >RF
relay switch is designed to withstand exposure to sine and random vibration
and mechanical shock.
The June 1945 edition of
Radio-Craft published a death notice for diode electron tube inventor
Sir Ambrose Fleming. The date given was April 19th, but every
source I can find says he died on April 18th. With having been born on November
29, 1849, that made the good fellow 95½ years old. According to a calculator
on the TimeAndDate.com website, that's a grand total of 34,900 days. Who's going
to argue over a potential 0.00287% error?
Barney Miller
My favorite character in the
1970s Prime Time TV show
Barney Miller
was Detective Sargent Arthur Dietrich. He was the serious intellectual with a very
dry sense of humor that came out at just the right moment. One episode has always
stuck out in my memory where a college student claims to have built a working model
of a thermonuclear
bomb as part of his Master's thesis project. All it lacks for detonation, per
him, is plutonium. The on-hand bomb squad expert ridiculed the idea of it being
any kind of real bomb, his decades of experience on the force being his guide
(still has all his fingers as proof of it). All the
guys in the office have just finished
...
The geographic
center of the 48 contiguous (conterminous) states
in America is located about 2.6 miles northwest of the center of Lebanon, Kansas
(39° 50' N, 98° 35' W). That is about 85
miles from the FCC's first central
frequency monitoring station at Grand Island, Nebraska. I have
driven by that spot a couple times while traveling on Interstate 80. Grand Island
is probably not much bigger today than it was in 1932 when this story was published
in Radio-Craft, although it boasts being the state's 4th largest city
(population 48,000). "Island" must have a different
definition in Nebraska than in the rest of the world ;-) Because of its remoteness
- 6 miles from town to minimize electrical noise - a diesel generator
(chosen to
...
In
the episode embedded below, titled, "Sweatwork," (a takeoff on the 1976 movie
"Network"), produced from my purchased copy of the
Welcome Back, Kotter DVD set, is about the Sweathogs running
a radio station in the school. On the blackboard outside of the broadcast studio
is a schematic for a vacuum-tube-based AM transmitter. It looks legit, and includes
all the components to form a basic transmitter, including the audio input. I could
not make out the manufacturer of the transmitter cabinet in
...
Guerrilla-RF-Access-Point-Amplifier-2-2-2015.htm" >
Guerrilla RF Inc., a leading provider of high
performance MMICs, today introduces the newest members to the company's family of
5 GHz ultra low noise amplifier/linear power amplifier drivers. These new devices
feature best-in-class noise figure , gain and linearity. The cost-effective, small
footprint, flat-gain solutions are designed for WLAN access points offering the
highest levels of performance for demanding 802.11ac applications. The
GRF2505 features ultra-low noise and high linearity
over the 5 to 6 GHz band making it ideal as either an LNA or as a power amplifier
driver for demand Guerrilla-RF-Access-Point-Amplifier-2-2-2015.htm" ...
While working at RF Micro Devices
(now known as Qorvo) on a project to improve the ESD
ruggedness of our RFICs, I had to do a number of presentations on progress over
a span of about two years. I desperately searched online for this episode of Welcome
Back Kotter titled "Sweathog
Clinic for the Cure of Smoking." It was not available at the time, but did show
up for a short time sometime around 2008. Then, it disappeared and was not available
again anywhere until a few months ago when a DVD set for the
Welcome Back, Kotter television series went on sale at Amazon.com. I quickly
snatched a copy and produced this clip
...
Alcohol Dispenser Bottle
One of the
first things you learn in chemistry class is to never contaminate a source by dipping
a spoon or other implement into the container, and not to allow an object like a
cloth or your finger to touch the rim of a container. Don't breathe into it, either.
Always 
pour or pump or use a dedicated implement to effect
the transfer of a source to a receptacle vessel. The other thing you learn early
on is to always - always - label your container with its contents. If you are a
user of alcohol, acetone, MEK, or other chemicals and routinely need to have access
to small amounts, it can be a pain in the posterior to have to keep pouring from
the primary container into a medicine cup, tin, or other temporary holder. During
both soldering of electronics and gluing of mechanical assemblies, I very often
need to access some type of chemical for cleaning with a Q-Tip or acid brush. These
kinds of chemical dispenser bottles ...
As
time marches inextricably forward, my appreciation for the artistic ability, craftsmanship,
and creativity of others seems to be growing on an exponential
(or maybe it's geometric) scale - particular pertaining
to the younger subset
of humanity. It probably has something to do with having crossed the half-century
threshold and realizing that I don't have enough time left in this world to accomplish
the multitude of activities or reach the many personal goals set. Everything seems
harder these days, particularly when trying to learn something completely new; the
old adage about not being able to teach an old dog new tricks is hitting closer
to home all the time. Nevertheless, I persist in spite of diminishing odds. Generational
pride still causes me to admonish an uppity teenager or twenty-something
...
Solutions Featured at
IMS 2015
Orbel-experts-EMI-RFI-solutions-IMS-2015-2-2-2015.htm" >
Orbel Corporation, designer and manufacturer
of custom EMI/RFI
shielding, photo-etched precision metal parts, and precision metal stamping
will be featuring their EMI/RFI solutions at IMS 2015. Products include board level
shielding, finger-stock gaskets and metalized fabric gaskets. Orbel-experts-EMI-RFI-solutions-IMS-2015-2-2-2015.htm" >Board
level shielding is used to restrict the amount of electromagnetic energy propagating
between the source and a receptor to acceptable levels. Near-field effects, layout
and hole design, resonances, and thermal management are all elements Orbel takes
into consideration in relation to shielding effectiveness. Finger-stock Orbel-experts-EMI-RFI-solutions-IMS-2015-2-2-2015.htm"
...
Since deciding to discontinue the hosting
of private advertising on RF Cafe, I have had many requests to resume the program.
Serving between 7,000 and 9,000 pages each weekday provides a valuable amount of
exposure to people like you - serious engineers, technicians, students, and hobbyists.
While I do not plan to reconstitute private advertising anytime soon, there remains
a very easy - and FREE - way for you to get your company's products and services
in front of RF Cafe visitors:
Press Releases. If your company makes products that I deem relevant to my readership,
I will gladly post your press release, company news, product announcements, etc.
Please send the information, along with ...
A Revealing Quiet
The "Sherlock Ohms" series published on occasion by
Design News, in case you have forgotten because of how long it has been
since I highlighted an episode (not many good ones lately,
IMHO), is a feature where engineers and technicians tell their stories of
troubleshooting intrigue based situations experienced in on-the-job or other venues.
"A Revealing Quiet," by Jason W. Evan, describes
one of those oh-too-familiar "aw crap" moments that has a nasty habit of appearing
just when all the world seems right with your project. Enjoy.
"Engineers are artists.
These are people with visions that no one else sees or hears, and the only other
domain like that is art." Steve Blank, retired serial entrepreneur and
Silicon Valley historian, in Entrepreneur magazine's "Inside the Mind of
Silicon Valley's Tech Innovators."
If you're a Seahawks
fan and you are looking for a new job, then all things might look a little bleak
at the moment for you. On the other hand if you're a Patriots fan and you are
looking for a new
job, then you probably feel pretty invincible this morning. Either way, many
'experts' believe that now is a pretty good time to be in the job market because
there is reportedly a severe talent shortage worldwide. I actually read one article
today where the author claims the announced planned massive layoff by IBM is a great
opportunity for those in the crosshairs - of course
...
-
Science-Backed Secrets for
Achieving Success in Life
-
Career Tips from World's
Leading Bosses
-
Ways Employers Discourage
You from Negotiating Salary
-
Contract or Part-Time Work
as a Stopgap? <more>
As
is frequently the case, John T. Frye's intrepid teenage technophile experimenters,
Carl Anderson and Jerry Bishop, find themselves in an unplanned
adventure. Often times they end up applying their electronics knowledge to bail
themselves out of trouble, but this time the pair - and a friend - ended up helping
the police catch some bad guys (an oft-occurring theme).
As you will see after reading "All's Fair --," the device used would some day
(today) be used by automobile manufacturers, at the
behest of law enforcement agencies, to enable remote control of somebody else's
...
Jules Antoine
Lissajous was a French mathematician who in the days before oscilloscopes concerned
himself with patterns (waveforms) that would be generated
as the result of two separate functions (signals)
driving both the x- and y-axes. Lissajous used mechanical vibration devices connected
to mirrors to bounce light beams onto a projection surface, so his results were
not merely hand-drawn plots on graph paper. He was probably as mesmerized with them
as we are today when they appear. Sci-fi movies have used Lissajous patterns in
the background to 'wow' the audience into thinking it is witnessing futuristic,
cutting-edge technology. When troubleshooting analog circuits
...
A Bit of TV History
It
is the opinion of historians that in order to understand the present, you need to
know the past. Searching for one's roots in this world is big business. Online family
tree type websites are used by thousands of people to research their family histories,
and some services don't come cheap. You can even pay someone to dig into your past
to assimilate all available information and put it in a bound, printed volume. Here
on RF Cafe, I research and post a lot of our profession's past. While
the individual topics themselves might no bear significantly on the present, having
an insight into the people's mindsets and progression of technology is
...
