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Friday the 17th
Thursday the 16th
Wednesday the 15th
Tuesday the 14th
 Mac's Service Shop captures here a
moment of technological transition in 1961 where a new "Loud-speaking Telephone"
impresses his right-hand man, Barney. The device utilizes vacuum-tube amplifiers
and a bulky external control box to allow hands-free communication, enabling Mac
to work while handling customer inquiries. Mac, ever the mentor, contrasts this
tube-based unit with the emerging technology of transistorized speakerphones,
which eliminate the need for external control boxes, external power supplies,
and warm-up times. The 1961 "Loud-speaking" setup, occupying significant space
under a workbench, has been completely replaced by modern smartphones and
integrated VoIP systems...
 As with all
RF Cafe
crossword puzzles, this one uses only words pertaining to engineering,
science, mathematics, mechanics, chemistry, astronomy, etc. 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!
  The microwave klystron was invented in 1937
by brothers
Russell and Sigurd Varian. If you have been in the microwave design
business for a couple decades, you undoubtedly recognize the company name of Varian
Associates, especially if you worked in the aerospace or defense electronics business.
There is a
video on YouTube of a segment on Varian done sometime around 1990
by Walter Cronkite. There is also a historical piece on Varian Associates on the
Communications & Power Industries website. This circa 1952 article covers the
fundamentals of klystron operation and reports on the increasing use of klystrons
in high
frequency application - including by amateur
radio operators exploring...
 Werbel Microwave began as a consulting
firm, specializing in RF components design, with the ability to rapidly spin low
volume prototypes, and has quickly grown into a major designer and manufacturer
with volume production capacities. The
WMRD02-7.2-S is a resistive splitter that covers up to 7.2 GHz with
ultra-wide bandwidth. This design is useful when there are many low power
signals within a wide spectrum. By design, the nominal insertion loss and
isolation is 6 dB, hence it is often referred to as a "6 dB splitter." Its small
size makes it easy to integrate into compact systems. Designed, assembled, and
tested in the USA. "No Worries with Werbel!"
 Contributors to the Wikipedia article on
the
Yagi–Uda antenna credit Japanese professor Shintaro Uda primarily for the antenna's
development, with Hidetsugu Yagi having played a "lesser role." Other sources assign
the primary role to Yagi. Regardless, history - and this article's author, rightly
or wrongly, has decreed that this highly popular design be referred to commonly
as the Yagi antenna and not the Uda antenna. I don't recall seeing advertisements
for "'Uda" television or amateur radio antennas. Harold Harris, of Channel Master
Corporation, does a nice job explaining the fundamentals of the Yagi antenna. Another
Yagi article appeared in the October 1952 issue of QST magazine...
 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.
Monday the 13th
 The production of high-performance transistors
necessitated new methods to achieve extreme purity levels, far beyond standard industrial
capabilities. To reach the required purity of
one part in ten billion, engineers adopted zone melting, a sophisticated technique
pioneered by W. G. Pfann. In this process, radio-frequency heating coils melt a
narrow zone of a semiconductor rod, which is then moved along the crystal to sweep
impurities to one end. Beyond purification, zone melting allows for the precise,
uniform introduction of "dopants" like antimony or indium, which are essential for
creating p-type and n-type semiconductor characteristics. By refining these methods
through continuous processing and floating-zone techniques, manufacturers significantly...
 Here's another advertisement that you probably
wouldn't see in a contemporary RF / microwave engineering magazine. For that matter
you probably wouldn't see it on a contemporary RF / microwave engineering website
... except on RF Cafe where political correctness gets no respect.
Adson Radio &
Electronics was located on Fulton Street in New York City, just a block from the
911 Memorial. the original building might have been destroyed when the...
 My first thought when seeing the cover for
this edition of Radio-Craft magazine was that it was an April Fools gag,
but it turns out the "hat" being worn by the radio receiver's designer is a
loop antenna for AM reception. Ya' know, he does look like he
could be a suicide bomber. In a way it is the opposite of a tinfoil hat in that
this headgear invites electromagnetic energy around the wearer's head rather than
shielding it. Back in 1936, being seen in public donning a contraption like this
radio would have been akin to Google Glass today - you'd be a superhero to fellow
nerds, and just be confirming your otherworldly nerd status to non-nerds...
 Vreeland Corporation was an early radio
manufacturer located in Hoboken, New Jersey, with multiple patents on file for innovative
circuits. The
Vreeland band selector system mentioned here was originally filed
in the U.S. Patent and Trademark Office in August of 1927 and had not been awarded
by the time of this November 1929 article in Radio-Craft magazine. In fact,
it wasn't until five years later, in 1932, that the patent was finally assigned.
The official description reads in part, "The general purpose of the invention is
to receive the component frequencies of such a band with such uniformity as to avoid
material distortion of the modulated wave, and to exclude frequencies outside of
the band which the system is designed to receive. Another purpose of the invention
is to provide means for shifting the position of the band...
Friday the 10th
 In this 1959 Radio-Electronics
magazine promo, Bell Telephone Laboratories showcased its advanced
radio-inertial guidance system, a technological breakthrough enabling precise
long-range missile flight. Developed for the Air Force's Ballistic Missile Division,
this innovation proved its efficacy by guiding a Thor-Able nose cone to a precise
target five thousand miles away, allowing for a successful aerial and maritime recovery.
The system utilized a missile-borne transmitter to feed continuous data to ground-based
radar and a Remington Rand Univac computer, which calculated real-time steering
corrections. By keeping the primary command equipment on the ground...
 It's Friday afternoon as I post this installment
of
Mac's Radio Service Shop from a 1952 edition of Radio &
Television News magazine - the perfect way to burn off the last few minutes
of your work week while waiting for the shift-ending whistle to blow. John T.
Frye authored many of these stories that used main characters Mac McGregor, proprietor
of Mac's Radio Service Shop and sidekick technician Barney to set up a situation
and dialog whereby the highly experienced Mac imparts sage advice to Barney regarding
things electronics in nature. Topics range from safely troubleshooting a high voltage
power supply to tracking down noisy capacitors and how to treat customers equitably.
Today's lesson is on the employment of "repurposed" (a term not yet invented in
1952...
 Thomas Edison applied on November 4, 1879
to the U.S. Patent and Trademark Office for a patent on his "Electric-Lamp." Patent number 223898 A was awarded on January
27, 1880. Remember those years. While searching for technical headlines today, I
ran across an article in the New York Times where they point out the first-ever
mention of electric lights in their newspaper. Per the article "The Arrival of Electric
Light," The New York Times first wrote of the technology on April 15, 1858.
On that day, "Our Own Correspondent" in Havana described celebrations of Holy Week
that included "an electric light" cast across the harbor...
 This is part 5 in a series that began in
the October 1951 issue of Radio & Television News magazine. Previous
articles dealt with
crystal diodes in AM and FM radios, and this article shift gears
by moving into television applications. Crystal diodes were and are still used in
frequency generation, envelope detection, frequency mixing, and AC signal rectification.
Vacuum tubes could be used for the latter three applications but many physical issues
such as size, weight, power consumption, and heat dissipation proved to be major
drawbacks as designers strived to reduce the size of electronics assemblies, make
them more energy efficient, lower the cost of manufacturing, increase reliability,
and decrease weight...
Thursday the 9th
 This article from a 1959 issue of Radio-Electronics
magazine details a simple, effective method to
convert a standard dipole antenna into a unidirectional, broadband performer
by bending it into a circular loop and terminating the ends with a non-inductive
resistor. By utilizing a cross-shaped support frame with TV standoff insulators,
a builder can easily construct this antenna for the 6-meter band or higher. The
design is noted for its impressive front-to-back ratio and surprising operational
versatility across a wide frequency range, even maintaining performance when improperly
sized. Offering increased gain at harmonic...
 As evidenced in these mid-last-century magazine
advertisements,
Sylvania Electric marketing moguls learned early what sells products
by exploiting the nature of their audience. The cartoon-style ads shown here appeared
in social publications like Look, Life, and Collier's, where both men and women
- many of them numbnuts - are the expected audience. Compare these with the type
of ad run by Sylvania in a "serious" magazine like
Radio-Craft...
 Billed at the time as the longest microwave
relay system in the world, this report on Bell Telephone Systems'
transcontinental installation came just a month after being put into commercial
service. At a cost of $40 million ($512 million in 2026 dollars per BLS Inflation
Calculator), the system relays telephone calls and radio and video program material
along a chain of 107 microwave towers, spaced approximately 30 miles apart. It was
a big deal to be able to watch a TV show from New York City in Los Angeles, and
vice versa; we take worldwide broadcasts for granted nowadays...
 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 models have been added to the
product line in April, including a 4.9 to 24 GHz MHz suspended stripline
highpass filter, a 9200 MHz cavity bandpass filter with 250 MHz bandwidth,
and a 1 MHz LC bandpass filter with 350 kHz bandwidth. Custom RF power
filter and directional couplers designs...
 Today as I write this it is New Year's Eve.
The year 1935 could be considered "metal tube's eve" as a new paradigm was about
to hit the world of high frequency circuit design. Thentofore[sic], vacuum tubes
were almost exclusively encased in a glass envelope.
Metal-encased tubes provided, among others, benefits like better
heat dissipation, smaller physical size, ruggedness, inherent RF shielding, and
lower parasitic values of capacitance and inductance due to smaller plate areas
and shorter lead lengths, respectively. The highest barrier to widespread adoption,
history would show, was the higher cost of production that made consumer products
more expensive at a time when not every household saw the need for...
Wednesday the 8th
 "Squegging,"
a phenomenon likened to the rhythmic spurts of a manual water pump, occurs when
an oscillator undergoes periodic cycles of oscillation followed by a dead period.
This happens when an excessive time constant in the grid circuit, often caused by
a faulty resistor or capacitor, drives the tube to cutoff, only for it to restart
once the bias bleeds off. In radio and television, this manifests as audible buzzing,
intermittent sound, or dark holes in the picture. Historically, the term "squeg"
emerged in the specialized fields of radio engineering and electronics during the
early 20th century, likely originating as a form of "self-quenching," descriptive
of the erratic...
 If
Radio Corporation of America (RCA) was still in existence today, undoubtedly
it would be running an advertisement mentioning not just radio and television in
their list of wireless communications accomplishments, but also cellphones, satellite
navigation (GPS), cable television, and Wi-Fi. Founded in 1919, RCA was bought by
General Electric in 1986 and then subsequently broken into components and sold off
to other companies like Sony, NBC (National Broadcasting Company), and Comcast.
This RCA advertisement heralding Marconi's Morse code message "first forged
in 1901 from the mere sound of three dots" appeared in a 1952 issue of Radio &
Television News magazine...
 "Researchers have created an
ultra-compact nanolaser
that could transform how data moves within microchips, replacing electrical signals
with light. The idea of computers communicating with light instead of electricity
is moving closer to reality, thanks to a breakthrough nanolaser developed at the
Technical University of Denmark (DTU). Described in Science Advances, the device
is small enough to be embedded by the thousands onto a single microchip. Instead
of relying on electrical currents, which generate heat..."
 It seems that creating almost cartoonish-looking
antenna arrays for the purpose of signal gain and directivity are usually relegated
to the domains of military and amateur radio practitioners, but this article from
a 1952 edition of Radio & Television News magazine was done by the
Channel Master Laboratories television antenna company. Successfully
mounting and phasing even two antennas can be challenging, but in this case
four Yagis were arrayed and tuned for operation. Trying to make
the system work over the entire 4 octave band that is the VHF broadcast realm (54
MHz for channel 2 to 210 MHz for channel 13) would be nearly impossible without
extremely...
 First prize in this circa 1936
reader-submitted design ideas went to William G. Scott for his
wind-powered battery recharger. It was a rather elaborate contraption made of surplus
lawn mower and automobile (Ford Model T, no less) generator. There are two very
good reasons why someone would find the need to build his own battery charger in
the era. First, good luck finding a commercial product to do the job, and if you
could, the cost would be prohibitive for most radio enthusiasts. Second, prior to
the Rural Electrification Act of 1936, most households not in or near cities and
towns had no commercial electric service. Electricity, if any, was...
Tuesday the 7th
 Technodrama stories were a popular means
of teaching valuable lessons back in the mid-twentieth century. Carl and Jerry,
Mac's Radio Service Shop, Sally the Service Maid - even Hobnobbing with Harbaugh
- et al, were very popular features. Popular Science magazine's Gus Wilson's
Model Garage was a gearhead equivalent. An occasional non-regular feature appeared,
as with this "Pedro
and the Swami" troubleshooting adventure in a 1959 issue of Radio-Electronics
magazine. You will like the ending. As a long-time troubleshooter of electrical,
mechanical, and hydraulic systems, I always read these kinds of things. Pull up
a chair and take a read through it; you will appreciate the combination of reductio
ad simplicitatem, reductio ad absurdum...
 These two
electronics-themed comics appeared in circa 1952-53 Radio &
Television News magazine. For some reason the early 50s were a little comic
challenged. I really like the one with the guy hanging from the antenna! It's hard
to make out the artists' names, but they have appeared on other comics of the era.
If you enjoy comics like this, there is a growing list of other comics at the bottom
of the page you can check out. I took the liberty of colorizing them...
 "Engineers aren't bad at communication.
They're just speaking to the wrong audience. There's a persistent myth that
engineers are bad
communicators. In my experience, that's not true. Engineers are often excellent
communicators - inside their domain. We're precise. We're logical. We structure
arguments clearly. We define terms. We reason from constraints. The breakdown happens
when the audience changes. We're used to speaking in highly technical language,
surrounded by people who share our vocabulary. In that environment, shorthand and
jargon are efficient..."
  RF Cafe visitor Mike H. sent me these
two photos of the same type Silvertone radio as I discovered in Tony Packo's. He
says there is no part number marked anywhere, so its identity was still a mystery.
Well, no more! I decided to use my paid subscription to newspapers.com to search
for an advertisement from an old newspaper. Sure enough, there was a full-page advertisement
by Sears, Roebuck, and Co., in the October 23, 1936 edition of the Rio Grande
Farmer that appears to include this model. Until proven otherwise, I hereby
declare the
Tony Packo's radio to be the "7 Tube Silvertone Battery Console."
Battery powered radios were quite common in 1937 because commercial AC power distribution
lines did not extend to many rural locations, and many urban homes...
 Maybe it isn't so anymore, but according
to Centralab the ceramic raw materials available in abundance in America were electrically
superior to those being used in Europe since the early 1900s when German scientists
first discovered the dielectric properties of the material.
Ceramic capacitors represented a major advance in capacitor technology
over liquid and paste dielectric types in most areas of electrical and mechanical
specifications such as vibration, aging, vibration and shock, temperature, value
stability, voltage and current handling, etc. Centralab ran this advertisement spelling
out all the virtues of ceramic capacitors...
Monday the 6th
 Radio-Electronics magazine ran a monthly
"News Briefs" section that corralled happenings in the industry. Included were inventions,
product announcements, events, demonstrations, job promotions, company headlines,
and even death notices. Notably in this 1959 installment was the announcement of
the passing of one of the
Varian brothers, Russell. He and his brother, Sigurd, are credited with inventing
the klystron microwave tube. Also highlighted was the short-lived phenomenon called
the Ovitron. It was a current-amplifying device that consisted of two plates immersed
in an electrolyte, with a control grid modulating the current - essentially a liquid
tube as opposed to a vacuum tube. The Ovitron suffered...
 Assuming the 10 enumerated advantages of
a gridless vacuum tube may be added to the 17 enumerated disadvantages of a gridded
vacuum tube, there are 27 reasons, per author Henri Dalpayrat why one should consider
abandoning the "old style" tubes for his revolutionary concept.
Part 1 of this 2-part series discussed the unavoidably negative
features of a gridded vacuum tube. Part 2, presently, extolls the wonders of a gridless
tube. Chief among the features is the use of "compressor bar" elements that are
situated parallel to the electron flow rather than in series with it. Another major
difference is the cathode element...
 "SpaceX
has filed confidential paperwork today for its initial public offering (IPO), according
to Bloomberg and the New York Times. The company plans its IPO for June and founder
Elon Musk aims to raise $50 billion to $75 billion, which would make it the
largest IPO Wall Street has ever seen. SpaceX currently values itself at more
than $1 trillion, according to the NTimes. The company is an umbrella that includes
not only the SpaceX rocket company but also xAI, Starlink, Grok and X. A confidential
filing means that the financials of the company are not disclosed until later..."
 The ability to generate clean, controlled
radio waves at 3 THz in 1937 was about as attainable as putting a man on the
moon. That did not stop scientists and engineers from theorizing how to get there
and what to do once attained. That's the way science progress happens. An official
name had not yet been given to the spectrum realm, but news reporters conjured up
the moniker "mystery rays." Even scientists called it the "black gap." Both sound
a bit hokey and there is a temptation to poke fun at the renown technical ignorance
of most media types, but no less a science giant as Albert Einstein referred to
quantum entanglement as "spooky action at a distance." The big idea of author W.E.
Shrage was to exploit and extend the concept of a cathode ray tube (CRT) to convert...
 CPC Amps recently released its latest product
to complement their full line of solid state high power RF and microwave amps. Pulsed
RF system requirements are now easily met with CPC Amps' S-band solid state power
amplifier (SSPA). Operating from 2700 to 3500 MHz, the
AM-2700-3500-2E2 will deliver up to 250 W of power with 48 dB of nominal
power gain for pulsed applications including radars, radar test equipment, and EW
systems. Pulse widths of 200 µs with duty cycles of 20% are easily supported.
Built in a rugged, low-profile connectorized housing, the unit delivers superior
performance in a small form factor...
Friday the 3rd
 You know you've gotten old when you have
an "I remember when..." line for just about every kind of product or process mentioned
in a magazine article, video, or conversation. Here is mine for microwave ovens.
I remember that it was sometime around 1977-79 that my father gave my mother a
microwave oven for Christmas. It was the most expensive gift anyone in our household
had ever received. According to this 1971 Radio-Electronics magazine article,
household microwaves had only been on the scene for about a decade. A look at the
wiring diagram shown for this International Crystal microwave...
 Reading through this article reminds me
of studying for the amateur radio exams. In fact, the information presented in this
1940 QST magazine piece does not seem to be lacking anything that contemporary
discussions include. My point is that a great amount of knowledge had already been
amassed about earth's
upper atmosphere a mere four decades after the first transatlantic
radio communications were accomplished by Marconi on December 12, 1901 from Poldhu
in Cornwall, England, to Newfoundland, Canada. Considering that at the time no instrumented
sounding rockets had been launched into the extreme upper layers (F1 & F2, beginning
at around 120 mi | 200 km), a lot had been discerned about characteristics as they
pertain to radio communications. Balloons were...
 "We've seen the writing on the wall for
awhile that data centers need fiber and lots of it. Research from RVA LLC has now
done the math and worked out that providers need to build about
92,000 new route miles in the next five years to support that demand. Suffice
to say, the pressure is on for suppliers. 'Everybody talks about the constraints
of power, cooling, land and chips and so forth, but fiber is also a constraint,'
said RVA Founder and CEO Mike Render at a Fiber Broadband Association (FBA) webinar
Wednesday. He noted a single cable can contain 'hundreds or thousands' of fiber
strands and that cabling will only get smaller..."
 These three
electronics-themed comics appeared in the November 1948 issue
of Radio & Television News magazine. You don't need to be of the era
in order to appreciate the humor, but Millennials might need a little assistance
with the second one. That contraption sitting the desk is called a "turntable,"
and it used to play audio media called "records" by spinning them at a certain rate
(33-1/3 rpm, 45 rpm, 78 rpm), while that horizontal lever called
a 'tone arm' held a piezoelectric needle in the grooved tracks of the record. The
joke here is the guy having to spin his head while trying to read the printed label.
I'm just joshing the Millennials, of course, since they use spinning disks called
CDs and DVDs for listening...
 These are
close-up photos of common household objects. Your mission, should you decide
to accept it, is to identify each one. Most are fairly easy, but a couple are a
little outdated since they appeared in a 1939 edition of Boys' Life magazine.
Answers are way down at the bottom of the page. BTW, this January issue is the one
Ralphie Parker is reading in the movie A Christmas Story...
Exodus AMP20110,
0.5-6 GHz, 150 W SSPA
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Exodus'
AMP20110 is a rugged, ultra-broadband solid state power amplifier (SSPA) designed
for all applications. Frequency range of 500 MHz-6.0 GHz (P-, L-, S-band),
150 W minimum, and 53 dB gain. Excellent power/gain flatness as compared
to other amplifiers. Forward/Reflected power monitoring, VSWR, voltage / current
/ temperature sensing...
Thursday the 2nd
 This 1971 Radio-Electronics magazine
article provides a comprehensive technical overview of
laser theory and practical application. It explains that laser action requires
a population inversion within a medium, typically contained in an optical cavity
with reflective surfaces to amplify coherent light through stimulated emission.
The author distinguishes between three-level systems, such as the ruby laser, and
four-level systems, exemplified by the helium-neon gas laser. Advanced techniques
like Q-switching are described as methods to achieve high-power pulses by interrupting
the cavity. Beyond core physics, the text explores the diverse utility of lasers
in engineering and biology...
 Next Spring I will be installing an old-fashioned
(but newly manufactured)
Channel Master television antenna on a short tower with a rotator.
Here in Erie, Pennsylvania, under certain conditions I can receive broadcasts from
Erie and many of the cities that border close to Lake Erie like Toronto and Waterloo,
Canada and even Detroit. AM radio stations are easily pulled in from the same areas,
but FM does not do quite so well. I plan to also integrate some form of FM antenna
on the installation. There is something insulting about paying for cable or satellite
TV and then having to suffer the deluge of commercials as well (I have neither).
Nobody likes sitting through commercials, but at least if the programming is being
delivered at no cost, it is not unreasonable for the broadcast...
 "Just when you thought it was safe to go
back into the networking waters, the Federal Communications Commission (FCC) throws
a curveball. This one is directed squarely at the consumer-grade router industry.
The FCC on Monday announced that all
consumer-grade routers produced in foreign countries are banned from sale in
the United States – unless the supplier applies for and receives a 'Conditional
Approval' from the Department of War (DoW) or the Department of Homeland Security
(DHS). Existing Wi-Fi routers and those that were previously approved by the FCC
can continue to be operated and sold..."
 Before most people listened to radio and
television programming via cable, satellite, and/or the Internet, broadcasts were
received over the air, usually from local stations. A common problem in the days
of vacuum tube Ham transmitters back in the day was inadvertently causing
broadcast interference (BCI) or specifically in the case of television, TVI,
due to insufficient filtering, shielding, or design. Nowadays, we generally refer
to all such unintentional and incidental radiation as radio frequency interference
(RFI). Lots of articles were written on the subject in the 1940s through about the
1970s. Some RF spectrum is shared by more than one entity per FCC and other countries'
band plans, with primary and secondary allocations assigned...
 I have always been a stickler for creating
neat, orderly arrangements when building any type of circuit assembly. Many moons
ago when starting out as an electrician, I made a point of installing straight runs
of Romex type cable with no twists, evenly spaced staples, and keeping the identification
marking to the outside. Conduit was precisely bent and installed, again with organized
parallel runs and even spacing where possible. Circuit breaker panel wiring looked
like something seen in an Apollo space capsule. Electrical inspectors often complimented
my work. Moving on to an electronics career, the habits carried over when prototyping
and even when directing layout for production PCBs or chassis assemblies, including
cabling. The greatest enjoyment I had was when laying out runs of
waveguide...
Wednesday the 1st
 If you wanted to review a patent back in
1971, when this "Patent
Talk" article appeared in Radio-Electronics magazine, you would need
to submit a written request to the U.S. Patent and Trademark Office (USPTO) in Washington,
D.C., and submit a payment to cover the cost. Sometime in 1999, the Patent Full-Text
and Image Database (PatFT) was made available on the World Wide Web (WWW, aka the
Internet), in a TIFF graphical file format. Google Patents came along around the
end of 2006; it was a much more user-friendly search system (still is). The USPTO
has put a lot of effort into making the patent application process simpler - even
approachable by non-lawyers. Hiring a patent application law firm is probably the
easiest - even the best...
 "A
team of international researchers have developed a breakthrough way to observe what
is happening inside electronic chips while they are operating - without touching
them, taking them apart, or switching them off. The new technique uses
terahertz waves, a safe and non-ionizing form of electromagnetic radiation,
to detect tiny movements of electrical charge inside fully packaged semiconductor
devices. For the first time, this allows scientists and engineers to monitor electronic
components as they function in the real world. The study, published in the IEEE
Journal of Microwaves, involves researchers from Adelaide University in Australia,
U.S. technology..."
 Here is Part 1 of a three-part article on
attenuator pad and impedance matching articles that appeared in
Radio-Craft magazine. Although the focus is on audio frequencies, the principles
apply in general. It is interesting to read about wavelengths expressed in units
of miles versus feet and meters like we are used to seeing for radio frequencies.
Keep in mind that most of the decibel formulas used here are for voltage and not
for power. As a reminder, the decibel representation of a ratio is always 10 * log10 (x).
If you have a voltage ratio of V1/V2 = 0.5, then 10 * log10 (0.5) = -3.01 dB.
If you have a power ratio of P1/P2 = 0.5, then 10 * log10 (0.5) = -3.01 dB.
Does that mean that -3.01 dB of voltage attenuation is the same as 3.01 dB
of power attenuation...
 Before there was radio, it really didn't
matter much how much electromagnetic energy at any frequency was spewed into the
air and into electric wires as long as the amplitude was not great enough to physically
damage affected equipment. There was no need for an FCC or unintentional radiation
limit regulations. It was not long after radio came along that the presence of
electromagnetic interference (EMI) made itself painfully obvious
due to its presence on audio as static. Motor brush arcing, electrical atmospheric
phenomena (lightning, meteors), switching on and off of circuits, intermittent connections,
nearby radio spurious emissions, high voltage transformers, and in this case, neon
lighting were among...
|
 Here is a batch of
electronics-themed comics that appeared in the January 1949 edition
of Radio & Television News. The scene seen (hey,
homonyms) on the page 138 comic was commonplace in the 1940s when televisions
were relatively new and not every household had a set. The scenario repeated itself
in the 1960s when color sets were hitting the consumer market. Now, people can watch
TV on their smartphones while not at home so gathering 'round the television display
in a store is relegated pretty much to little kids watching the Disney movies that
seem to always running on them. There is a growing list of other comics at the bottom
of the page...
 In April of 1952 when this article appeared
in Radio & Television News magazine, the
bipolar junction transistor (BJT) had only made it out of the
experimental laboratory of Messrs. Bardeen, Shockley, and Brattain at Bell Labs
a mere three years earlier in December of 1948. It did not take long for commercial
production to begin. Along with being a great primer for anyone new to transistors,
herein is also some background on how the now ubiquitous BJT schematic symbol was
created. Interestingly, only Dr. William Shockley is mentioned, making me wonder
whether the contributions of Dr. John Bardeen, and Dr. Walter H. Brattain was
not widely publicized early on. Not to worry, though, because all three were duly...
 December 1942 was just a year into America's
"official" involvement in World War II. Already, both wired and wireless communications
had made major advances and were indisputably vital in both the logistical and strategic
aspects of troop movement, supply chains, fighting battles, and evacuation of wounded
personnel. It also played a large part in propaganda campaigns. This was all true
for both Axis and Allied forces.
Ham radio
operators provided a huge boost to the Signal Corps because they came at least
partially trained for the jobs. These dozen and a half photos from the field exhibit
the state of the art at the time. Maybe you'll recognize a father, grandfather,
or uncle in one of them. For that matter, you might even recognize a mother, grandmother...
 This is a must-read article for all persons
interested in the history of wireless communications. Seriously. Stop what you are
doing and read it. I guarantee the vast majority have never heard of this challenge
to the veracity of
Mr. Guglielmo Marconi's bestowed title of "father of wireless
telegraphy." Most of us are at least passingly familiar with challenges to Samuel
Morse's, Thomas Edison's, and a few other notables' claims to being the first at
a particular technical breakthrough, but herein, as penned by of
Lieutenant-Commander Edward H. Loftin, is a first-hand account
of multiple successful challenges by the U.S. Patent Office against...
 This nomograph from a 1959 issue of
Radio & TV News magazine simplifies matching a source (sending - s)
impedance (Zs) and a load (receiving - r) impedance (Zr) using a
quarter-wave transmission line. To use it, locate your Zs value on the left
vertical scale and your Zr value on the right scale. Lay a straightedge across
these points; the intersection with the center vertical scale reveals the
required surge impedance - also called characteristic impedance - (Z0). Surge
impedance is the ratio of voltage to current for a wave traveling along an
infinite transmission line, dictated by the physical geometry and dielectric
properties of the cable, defined as Z0 = sqrt (L/C), where L is inductance per
unit length and C is capacitance per unit length. The quarter-wave transformer
relies...
2016 January - 2
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