In much the same
way as the solution to a word problem seems obvious when you look it up in the
back of a textbook, Sylvania's answer to manufacturing a
vacuum tube heater element that is more robust and less subject to vibration
failure is illustrated in this advertisement which appeared in a 1968 issue of
Radio-Electronics magazine. Eliminating the suspended element and
wrapping it securely on a supporting post facilitated an "instant on"
requirement for up-and-coming transistorized televisions and radios by reducing
heat-up time to about a second. The heater's symmetrical shape also assured even
emission of electrons from the cathode. Its captured winding around the support
post also eliminated the annoying failure mode where a broken-off heater...
Amplifier Solutions Corporation (ASC) is
a manufacturer of amplifiers for commercial & military markets. 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. ASC is located in an 8,000 sq.ft. facility
in the town of Telford, PA. We offer excellent customer support and take pride in
the ability to quickly react to evolving system design requirements.
The
development
of capacitors dates back to the 18th century when scientists were exploring the
principles of static electricity. The first practical capacitor was the Leyden jar,
invented in 1745 by Pieter van Musschenbroek of the University of Leiden and independently
by Ewald Georg von Kleist in 1746. The Leyden jar consisted of a glass container
coated with metal foil on both its inner and outer surfaces, with a conducting
rod protruding from the top to connect to an external charge source. This device
demonstrated the principle of storing electrical charge, laying the foundation
for future capacitor technologies. Capacitors function based on the principle of
electrostatic...
• EVs Stall, Hybrids
Gain
• ARRL Launches
Dream Station Sweepstakes
• FCC Spectrum
Auction Pays for Huawei Rip-and-Replace
• 4G & 5G to Take off in
35 USAF Bases in 2025
• Magazine Highlights
Achievements in 6G Research
Popular Electronics magazine for years
ran a monthly electronics tutorial column entitled, "After Class." Various guest
authors wrote the articles. All you need to do is substitute transistors and
associated biasing and interstage coupling for the tubes used in these
fundamental crystal oscillator circuits to bring this article's content up
to date. Or, maybe you are the owner of a vintage vacuum tube radio and would
like to learn a little about how things were done in the olden days. Either way,
as with so many aspects of electronic circuits, the basics haven't changed much
in the last 100 years. It's all still good...
Established in 1990,
dB Control supplies mission-critical,
often sole-source, products worldwide to military organizations, as well as to major
defense contractors and commercial manufacturers. dB Control designs and manufactures
high-power TWT amplifiers, microwave power modules, transmitters, high- and low-voltage
power supplies, and modulators for radar, ECM, and data link applications. Modularity
enables rapid configuration of custom products for a variety of platforms, including
ground-based and high-altitude military manned and unmanned aircraft. Custom RF
sources and receivers, components and integrated microwave subsystems as well as
precision electromechanical switches. dB Control also offers specialized contract
manufacturing and repair depot services...
Lots of happenings in the tech world were
reported in the February 1964 "News
Briefs" section of Radio-Electronics magazine. The winner for best
item has to be where a little girl bit into a TV power cord and got launched a couple
feet into the air. The aftermath was gruesome. UNIVAC 1 was retired from service
at the Bureau of the Census where it crunched numbers since March 1951. Awarding
of engineering PhD and Master of Science degrees were on the rise, while Bachelor
of science degrees were in decline. No explanation was offered. Maybe the relatively
new hippie movement was causing...
"Researchers have created a new type of
optical memory called a
programmable photonic latch, which is both fast and scalable. This memory unit
provides a high-speed solution for temporary data storage in optical processing
systems, utilizing silicon photonics to enhance performance. The programmable photonic
latch is inspired by the set-reset latch, a fundamental electronic memory device
that stores a single bit of data. It works by switching between two states: set
(1) and reset (0), based on input signals. 'While optical communications and computing..."
Anatech Intros 3 Filters
for February
Anatech Electronics 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. Three
new filter models have been added to the product line in February, including a 5470-5725 MHz
cavity bandpass filter, a 4960 MHz cavity bandpass filter, and a 5530 MHz
cavity bandpass filter, all with low insertion loss and outstanding return loss.
Custom RF power filter...
"Praetersonic" - now that's a word you don't
run up against very often. It is a combination of praeter (beyond) and sonic (related
to sounds), or what more familiarly is called ultrasonic. If fact, praetersonics
was the early term given to
surface acoustic wave (SAW) piezoelectric devices. Amazingly, even as far back
as the early 1970s, SAW filters were being fabricated that worked in the 40 MHz
realm. This 1971 Popular Electronics article does a really nice job of
introducing the basics of SAW and BAW (bulk acoustic wave) technology...
Only two circuit challenges were presented
in the July 1969 "What's
Your EQ?" feature in Radio-Electronics magazine. "EQ," or Electronics
Quotient, is a play on "IQ," Intelligence Quotient. EQs are submitted by readers,
although occasionally one of the magazine editors contributes. "Lamp Switching"
is a classical puzzle where a mechanical switch and a handful of steering diodes
are connected, and your mission, if you choose to accept it, is to figure out what
is inherently wrong with the way the author constructed his circuit. He admits it
didn't work as planned, and invites you to come...
Electromagnetic absorbers are essential
in energy, stealth, and communication technologies, yet current designs underperform.
A research team has introduced ultra-thin absorbers nearing theoretical efficiency
limits, promising transformative industrial applications. Absorbing layers are essential
to advancements in technologies like energy harvesting, stealth systems, and communication
networks. These layers efficiently capture electromagnetic waves across wide frequency
ranges, enabling the creation of sustainable, self-powered...
Teledyne HiRel Semiconductors announces
the availability of its latest
rad-tolerant wideband 50 GHz RF switch, model TDSW050A2T. This switch operates
from true DC to 50 GHz, delivering excellent RF performance down to zero Hertz,
making this device ideal for many of today's complex space and defense applications.
It has been developed in a 150 nm pseudo orphic High Electron Mobility Transistor
(pHEMT) Indium Gallium Arsenide (InGaAs) process and is available in a 1.15 mm
x 1.47 mm x 0.1 mm die ideal for hybrid...
A while back I was using the familiar
analogy that relates water pressure, hose diameter, and flow rate to electrical
voltage, resistance, and current, respectively, in an explanation to my daughter
regarding why the water characteristics in her house changed after the well supply
pipe and indoor plumbing changed. The cause, I proposed, was due to an increased
distance between well and house, and the use of the plastic PEX tubing with a smaller
inside diameter than the old copper pipe, respectively. The submersible pump and
holding tank still supply the same 50 psi as before, but since that pressure
now has to force...
Warfare has evolved far beyond the conventional
image of tanks, troops, and artillery. In today's battles, control over invisible
forces often determines victory or defeat. One of the most critical of these forces
is the electromagnetic spectrum - a domain where Electronic Warfare (EW) plays a
pivotal role. EW involves the strategic use of electromagnetic energy to sense,
disrupt, or deny an enemy's capabilities, often without a single shot being fired.
Electronic Warfare has become an indispensable tool, shaping the outcome of conflicts
by dominating the unseen forces that power today’s military technology. everything
RF has created the
"Electronic Warfare" eBook to act as a comprehensive...
Here is a good old fashion
Q&A session on Ham radio topics, with the emphasis on "old." QST
magazine published a couple of these columns in the 1960s, and this is the second
in the series. It is the half-century-ago equivalent of the contemporary "The Doctor
Is In" column by the ARRL's Joel Hallas, W1ZR. I didn't read anything that wouldn't
be applicable today, especially if you have some vintage gear. As with most such
articles, there is something to be learned by just about anyone who deals with electronics,
especially in the RF realm. One particularly interesting part is where the author,
in response to a question about building and tuning your own radio...
The February 1964 issue of Radio-Electronics
magazine contained these three
electronics-themed comics. The one on page 48 reminds me of the time about a
decade ago when I was moving an old freezer out of someone's garage, and found underneath
it a huge skeleton of some sort of rodent or ruminant. I'm not sure what it was,
but given the ferocious teeth if had I was glad it was long dead. The page 100 comic
is my favorite. I didn't notice at first what was displayed on the oscilloscope.
"Getting" the page 109 comic took a moment, but the gag eventually hit me. I colorized
them to bring them into the 21st Century...
Join this
Automotive Radar Testing Seminar on Wednesday, February 26, 2025. The introduction
of the R&S RadEst revolutionizes automotive radar testing. It sets a new price-performance
point and provides radar developers and production managers with benefits such as
cost, space and time efficiency as well as assurance from accurate and reliable
results. In this webinar we will talk about the latest automotive radar technology
and market developments. We will dive deep into the radar lifecycle and test challenges
as well as the applications of the RadEsT compact target generator...
"Glasgow University researchers have led
work that could lead to a new generation of
diamond-based transistors for use in high-power electronics. Their new diamond
transistor is claimed to overcome the limitations of previous developments in the
technology to create a device much closer to being of practical use across a range
of industries that rely on high power systems. The team has found a new way to use
diamond as the basis of a transistor..."
An
iconoscope was an early
form of television image capturing tube. Some amateur radio operators were experimenting
with slow scan TV even back when the technology was relatively new to the world.
When this article was appeared in a 1944 of QST magazine, there were still
large portions of the United States that did not have television broadcast coverage.
Of course I would argue that at the time of my growing up in the 1960s and early
1970s a lot of areas - even suburbs - were still not covered by TV signals, based
on how cruddy the reception...
Continuing its long-time monthly "What's
Your EQ?" feature where readers submit electronics-related challenges, Radio-Electronics
magazine published these three in the December 1962 issue. I have to admit to not
getting the "120-240 Switchover" problem due to thinking only "inside the box."
I didn't consider that adding another component to the circuit was permissible.
I thought only the presented wires and component were available for use. Don't you
make the same mistake. "Voltage Quandary" was not as difficult, but took some head
scratching...
$1.6B in government loans gone up in steam.
"Maybe you've seen the unsightly, blindingly bright towers while traveling from
L.A. to Las Vegas, in the Mojave Desert near the California-Nevada state line. Maybe
you've read about birds getting fried to death as they fly through the sunlight
directed to the tops of the towers by fields of mirrors. When state officials agreed
to let Pacific Gas & Electric and Southern California Edison buy power from
Ivanpah roughly 15 years ago, they saw this type of technology - known as 'concentrated
solar power' - as the future of renewable energy. It was expensive...
During World War II, Americans, Britains,
Frenchmen, and other civilians were seriously engaged in helping to defend their
homeland. Those who were not in the military gathered bottles, tin cans, tires,
and clothing to use in the war effort. Others volunteered at the Red Cross, veterans'
hospitals, and USO offices. Some stood guard at their nation's seashores and land
borders, both as armed sentries and as troop and aircraft spotters. As part of the
civil defense effort, listening devices were built to help detect the sound of approaching
airplanes. In patriotic tradition, magazines like Popular Science published many
articles to assist the population contribute. Here is a plan for a "Homemade
Plane Detector." It used a horn "antenna" that...
It is Friday when this is being posted,
so that makes it a good day for these three new
electronics-themed
comics. They come from a 1967 issue of Radio-Electronics magazine,
so the scenarios are a bit outdated. However, even if you didn't live during the
era or have not read much about what the hottest topics and concerns of the era
were, you can still appreciate the humor. As recently as the 1990s and early 2000s
there were still a fair number of computer and electronics repair services around,
so even Gen Z'ers might remember them, and certainly Millennials (aka Gen Y)
. By 1967, vacuum tubes were disappearing from the repair scene as radio and TV
owners...
Sam Benzacar, of Anatech Electronics, an
RF and microwave filter company, has published his January 2025 newsletter that,
along with timely news items, features his short op-ed entitled "Wi-Fi
8 Is Coming, and It's All About Reliability," which discusses the major improvement
in data speed and reliability over all previous versions. The Wi-Fi Alliance predicts
a 10x growth in wireless connectivity from now until 2028. Automatic arbitration
between Wi-Fi zones for power levels, sub-channel assignments, and traffic handling,
is intended to deal with an increasingly dense operational environment. Wi-Fi operations
are nowadays conducted in both fixed and mobile scenarios where signal coexistence
requirements are continually changing not just from dynamic multipath conditions
due to reflections, but from constantly changing Wi-Fi bases station locations.
Incredibly sophisticated mathematics are required to implement the schemes.
"A new era in computing is emerging as researchers
overcome the limitations of Moore's Law through
photonics. This cutting-edge approach boosts processing speeds and slashes energy
use, potentially revolutionizing AI and machine learning applications. For decades,
computer and smartphone circuits have steadily become smaller and more powerful,
following the trend known as Moore's Law. However, this era of consistent progress
is nearing its end due to physical limits, such as the maximum number of transistors..."
This news suggests that nobody has been
tracking the flight trajectory of the
Tesla Roadster which Elon Musk launched into solar orbit on February 6, 2018.
"On Jan. 2, the Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics
in Cambridge, Massachusetts, announced the discovery of an unusual asteroid, designated
2018 CN41. It came less than 150,000 miles from Earth, closer than the orbit of
the Moon. That qualified it as a near-Earth object - one worth monitoring for its
potential to someday slam into Earth. But less than 17 hours later, the Minor Planet
Center issued an editorial notice: It was deleting 2018 CN41 from its records because,
it turned out, the object was not an asteroid. It was a car..."
Dr. Allen Du Mont played a huge
role in making television practical because of the improvements he made to the cathode
ray tube (CRT). Prior to his work, the lifespan of a CRT was measured in tens of
hours, and they were expensive, so their use was limited to special military and
research applications. Du Mont's interest in "wireless" began at an early age,
and he earned his commercial radio operator's license at the age of 14 (in 1915).
He designed and produced oscillographs (aka oscilloscopes) that incorporated his
CRTs. His involvement in the television industry was a natural evolution and extension
of the work done in related industries...
With as much ink as was used in reporting
on this "Major Antenna Breakthrough?" item in the July 1967 issue of Radio-Electronics
magazine, it could have qualified as a feature story. The breakthrough is an active
antenna, dubbed a
Subminiature Integrated Antenna (SIA), with amplifying transistors in series
with the radial elements. This hookup makes practical, it is claimed, to reduce
antenna length from 1/4 to 1/50 wavelength and still have reasonable signal pickup.
A TV or FM receiver version could be 2 or 3 inches long. Half a year later the magazine
had an SIA article entitled "Build a Mini-Tenna," which operated in the 88-108 MHz
FM radio band. There does not seem to have been a widespread...
|
');
//-->
Here is the promised follow-up on yesterday's
article, "TV X-Rays Are Back," from June 1969 issue of Radio-Electronics.
This
x-ray emission issue, whether legitimately a serious health problem or
not, was a big deal and was hyped up by the news media the way cellphones
causing brain cancer and laptop computers sterilizing men is done today. For a
while it measurably affected the volume of color television sales. X-rays are a
form of ionizing radiation (unlike microwaves which are not) and can thereby
cause cancer by rearranging atoms and molecules. At the root of the problem was
the extremely high acceleration voltage (HV) and beam current being used in the
cathode ray tube (CRT). Potentials in excess of 25 kV generated the most harmful
level of x-rays, so manufacturers redesigned sets to use lower voltages, and
also incorporated...
Moral standards seem to rigidly obey the second
law of thermodynamics, which states that entropy (disorder) increases in a closed system.
Most people would say society is more rude and corrupt today than in days gone by - count
me among them. However, believing so does not obviate or excuse acts of deviance in the
past. Indeed, even esteemed organizations like the
ARRL seems to have been guilty of promoting dishonest acts. To wit, consider this
offer appearing in the "Strayed" column of the April 1933 issue of QST magazine,
"For Sale: QSL Cards of any country. Win your WAC..."
Television (TV) and high fidelity stereo (HiFi)
were a big deal from the 1950s through the 1970s as
electronics technology underwent major improvements in component capabilities and
research produced high-complexity circuits that featured sophisticated methods of signal
processing. The industry went through the transition from vacuum tubes to transistors
during that three decade period, setting the groundwork for the next generation of microprocessor-based
audio-visual entertainment. Printed comics and TV and radio shows favorite themes included
jokes having to do with Joe Sixpack and his family's anecdotes involving television and
HiFi stereo. Here are a few more from the mid-1960s...
Here is a really good introductory article
on electromagnetic
(EM) fields as they pertain to inductors, transformers, and antennas. It appeared
in the April 1942 edition of QST magazine. The FCC had only been in existence for
eight years at the time and was pretty much just figuring out how to regulate the
heck out of everything. The author discusses compliance issues for these newfangled
RF devices that were becoming more and more numerous. Interestingly, the first sentence
says, "Every time you threw the transmitting switch in pre-war days...," bringing
to mind how the Feds banned Amateur Radio during most of World War II for security
reasons as well as to assure that scarce resources went toward building and servicing
military gear as needed. Many Hams offered their gear either as a donation...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
In my daily routine of perusing the WWW (World
Wide Web - remember that?) for good information to post, I need to copy images into
which thumbnail versions are made. A very recent trend has evolved for the sake
of mobile device displays which appends some sizing directives to the end of the
otherwise normal URL, and that prevents doing a copy and paste with right-click
-> Copy Image, and then paste it into a graphics editor. Instead, do
a right-click -> Copy Image Location
and then paste that URL into your browser. Click the thumbnail image above for an
example. Note the appendage after the ".png" file extension:
?auto=format&fit=crop&h=432&w=76"
That prevents the normal Image Copy from working. Delete everything after .png and
then hit enter. You should now be able to copy and paste the image into your editor.
Robert Balin created this
Electronic Factor Quiz for the November 1966 edition of Popular Electronics
magazine. Your challenge is to match the drawing of a particular electronics circuit
or implement with the corresponding "factor." Examples are "current amplification factor,"
"damping factor," "modulation factor," "duty factor," "form factor," "quality factor,"
etc. There are ten in all. Of course on a quiz like this you cannot get just one answer
wrong - or any odd number for that matter. I managed to reverse #5 and #10 (I and B,
respectively). For some reason I couldn't remember what "form factor" was, but was sure
that #10 was a scale factor of sorts... wrong - a clear case of cranial rectumitis...
RF Cafe visitor Mike M. sent this very
interesting note after reading this "Frequency
Modulation Fundamentals" article: Again, you hit it out of the ballpark, Kirt!
Great article out of QST. Absolutely accurate to credit "The Old Man" Edwin Armstrong
for the invention/development of FM and much more, plus the work of Dan Noble, who
worked with the Connecticut State Police and Motorola as Director of Research. Also
many, many others. Some that have never been properly credited. Guys like Bob Morris,
W2LV and Frank Gunther, W2ALS. They were both interviewed by Ken Burns for "Empire
of the Air". I was fortunate enough to talk to both of these guys after I got my
Tech license in 1970. My immediate supervisor/mentor from 1972 until he retired
in ~1990, was George. He was a superb mentor, who espoused the best engineering
methods and as he would say " the price of success is constant vigilance." George
had worked for Armstrong at the pioneering FM station, W2XMN in the late 40's and
early 50's. George had several stories about working for "The Old Man..."
In many ways a
crossnumber (aka cross number or cross figure) puzzle, which is an intersecting
grid of numbers, is more challenging than a standard crossword puzzle, which is
an intersecting grid of letters. John Comstock created a few of these crossnumber
puzzles for Popular Electronics back in the early days of the magazine. If you have
never tried creating a crossword puzzle, especially one that uses only technical
terms and has many interconnected squares in the grid, then you cannot appreciate
the frustration it can be. The nice thing about creating a crossnumber puzzle versus
a crossword puzzle is that every number is a valid "word" and it is therefore never
a problem to find a clue to go with it. For example, any random number can be the
answer to a clue that expresses ...
Homepage
Archives for January 2024. Items on the RF Cafe homepage come and go at a pretty
fast rate. In order to facilitate fast page loading, I keep the size reasonable - under a megabyte (ebay, Amazon, NY Times, etc., are multiple
megabytes). New items are added at the top of the content area, and within a few
days they shift off the bottom. If you recall seeing something on the homepage
but now it is gone, fret not because many years I have maintained
Homepage Archives.
Homepage
Archives for December 2022. Items on the RF Cafe homepage come and go at a pretty
fast rate. In order to facilitate fast page loading, I keep the size reasonable - under a megabyte (ebay, Amazon, NY Times, etc., are multiple
megabytes). New items are added at the top of the content area, and within a few
days they shift off the bottom. If you recall seeing something on the homepage
but now it is gone, fret not because many years I have maintained
Homepage Archives.
Each
year the Foundational Questions Institute (FQXi) holds an essay contest inviting
writers to submit missives addressing the question chosen by the FQXi board as being
particularly thought-provoking. In their words, "FQXi catalyzes, supports, and disseminates
research on questions at the foundations of physics and cosmology, particularly
new frontiers and innovative ideas integral to a deep understanding of reality,
but unlikely to be supported by conventional funding sources." The 2011 question
was "Is Reality
Digital or Analog?" (here is The Wayback Machine's capture of the original webpage).
Scientific American magazine, being one of three partners, published the runner-up
entry in the December 2012 issue: University of Cambridge professor of theoretical
physics...
This
electronics analogy quiz is a little easier than many of the others
published in Popular Electronics magazine because all of the electrical
and mechanical objects depicted here are very familiar. The concepts might seem
trivial to those of us who have been immersed in the science for decades, but I
for one can remember when first hearing these analogies how helpful they were.
Not only that, but I also recall during physics and mechanics courses in college
being amazed at the similarity of equations shared by electrical and mechanical
processes. Wikipedia has a huge page describing many of the most familiar
mechanical-electrical analogies...
Yay for us. Our
pollution production levels
are way down compared to what they were in the middle of the last century. Seriously,
things were getting really bad. Pittsburgh was considered such a hopeless mess that
famed architect Frank Lloyd Wright, whose landmark Fallingwater home sat nearby,
when asked what to do about Pittsburg's terrible pollution responded, "Abandon it."
Lake Erie had been declared officially dead. Love Canal dominated headlines. Los
Angeles air was (and still is, BTW) unbreathable. After huge public awareness campaigns,
cleanup efforts, and stricter enforcement of pollution laws, the trend halted and
has reversed. That is unquestionably good news. The bad news is that as pollution
control got better, companies found continuing manufacturing operations in the U.S.
was unprofitable based on what people were willing to pay for their products. Steel,
the literal and figurative backbone of industry, could not be mined, smelted, and
processed into finished goods at a price that would encourage innovation and growth...
A while back I was using the familiar
analogy that relates water pressure, hose diameter, and flow rate to electrical
voltage, resistance, and current, respectively, in an explanation to my daughter
regarding why the water characteristics in her house changed after the well supply
pipe and indoor plumbing changed. The cause, I proposed, was due to an increased
distance between well and house, and the use of the plastic PEX tubing with a smaller
inside diameter than the old copper pipe, respectively. The submersible pump and
holding tank still supply the same 50 psi as before, but since that pressure
now has to force the water through a path inside the house with more resistance
to water flow, the delivery rate to fixtures is now lower. When I hold the contacts
closed on the pump control relay, the most I can get is about 55 psi. Raising
the pressure will require replacing...
Alaska and Hawaii were added to the Union
as the 49th and 50th states, respectively, in 1959. Prior to that time, both were
referred to as possessions or territories. This story from a 1957 edition of
Radio & Television News refers to Bell Telephone Systems and the U.S. Army
Signal Corps laying the first cable for opening commercial telephone service between
Port Angeles (near Seattle), Washington, and Ketchikan, Territory of Alaska. The
900 mile,
submarine cable carried 36 circuits, and took 2 years to install at a cost of
$20 million ($192 million in 2021 money). Work conditions for crews were nowhere
near as accommodating or protected against accidents as they are today. As with
so many things, our forebears sacrificed life and limb, literally, to bring us to
the comfortable existence we enjoy today...
John T. Frye was an electronics service
technician long before he began writing techno-dramas like "Mac's Radio Service
Shop" and "Carl & Jerry." His expertise and real-world experience evidenced
itself in the wide variety of situations and subjects covered in the stories. If
you have never read any of them, I whole-heartedly suggest that you sample a few
(or listen to one of my podcast readings of them). In this article from a 1949 issue
of Radio-Electronics magazine, Mr. Frye discusses what was evidently
a reluctance on the part of service men to acquire and/or use
printed service data when troubleshooting and/or aligning radios, televisions,
tape recorders, etc. The attitude of some elitists was that if you needed to consult
documentation that it was evidence of your ineptness; you were not a worthy electronics
technician. More than one episode of "Mac's Radio Service Shop" had owner Mac McGregor
admonishing young Barney about wasting time during troubleshooting by not consulting
the service data sheets he stocks in the shop. Even if a shop owner could not afford
the elite service literature from SAMS Photofacts...
In this August 1963 adventure from Popular
Electronics magazine, teenage techno-investigators Carl Anderson and Jerry Bishop
use their home-brew sonar device to help the local sheriff nab a couple bank robbers.
The "Hydro Probe" mentioned in the article was a real product manufactured by the
Raymond Development Company of Watertown, Massachusetts (no longer in business).
By this time the duo were students pursuing electrical engineering degrees at Parvoo
University (a play on Perdue University, located in the boys' home state of Indiana).
Enjoy.
This
Science-Theme Crossword Puzzle for March 14th has many words and
clues related to... you guessed it... RF engineering - and mathematics, chemistry,
physics, and other technical words. As always, this crossword 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!
Homepage
Archives for February 2023. Items on the RF Cafe homepage come and go at a pretty
fast rate. In order to facilitate fast page loading, I keep the size reasonable - under a megabyte (ebay, Amazon, NY Times, etc., are multiple
megabytes). New items are added at the top of the content area, and within a few
days they shift off the bottom. If you recall seeing something on the homepage
but now it is gone, fret not because many years I have maintained
Homepage Archives.
The word "transformer" in the title for this
1943 QST magazine article does not refer to a mutual inductance transformer, but
an impedance transformer for
matching transmission lines to antennas (or anything else for that matter).
Author T.A. Gadwa gives examples of impedance-matching circuits both for when
the antenna impedance is lower than the characteristic impedance of the transmission
line and when the antenna impedance is higher than that of the feed line. "L," "pi,"
and a couple other circuit configurations are covered. Equations are also given... |