See Page 1 |
2 | of the December 2024 homepage archives. Tuesday the 31st
 Telstar 1 was a ball-shaped satellite
about 33 inches in diameter with a launch weight of 170 pounds. Its outer surface
had 72 flat facets, 60 of which had a total of 3600 solar cells to recharge 19 Ni-Cad
cells. On three facets were mirrors to reflect the sunlight to earth for optical
tracking. That was the state of the art in 1962, when Radio-Electronics
magazine editor Hugo Gernsback reported on its unqualified success. The September
issue contained technical details on the Telstar 1. It sported 93 dB of
receiver gain. In 1960, Mr. Gernsback wrote about "Future Space Traffic" in
November 1960, where he predicted "tens of thousands of spacecraft will soon be
aloft...
 If you have been around the RF Cafe
website for a while,
you are probably aware that one of my lifelong interests is building and flying
model aircraft. AirplanesAndRockets.com
is my hobby website. Each year the Academy of Model Aeronautics (AMA) hold national
championships for all forms of model aviation including radio control, control,
and free flight. Airplanes, helicopters, and theses day drones, are the primary
focus, while rockets, cars, and boats are sometimes featured. Various classes of
contents are conducted, including Expert and Standard, Senior and Junior, and others.
What really caught my attention this year and last year was the first name of the
champion for the Junior class of control line flying - Angstrom! Is that a great
name or what? It sure beats Kirt. The name, of course, is a unit of wavelength named
in honor of Anders
Jonas Ångström. Here is the origin of
Ebernez.
 "The
aging radio system used by train drivers and signallers across the United Kingdom
is the cause of a major disruption for rail commuters nationwide Friday - another
sign of the UK's failing infrastructure. Services out of major transport hubs in
London, Manchester and Southampton were affected, the BBC said. Trains to and from
London's major airports were roiled by delays. Great Northern, ScotRail, Southern
and many other lines were also impacted. National Rail blamed the delays on a failure
of its specialized GSM-R rail communications system, which is based on the 2G..."
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. We are pleased to announce
another industry first - the model
AMP4065LC-400 is a rugged 400 watt SSPA incorporating advanced technology for
18.0-26.5 GHz applications. Designed for high field level EMC Testing, Mil-Std
461(RS103) standards as well as other high-power applications, Exodus Model AMP4065LC-400
provides outstanding power/gain flatness, forward and reflected power monitoring
in both dBm & watts...
 Here is a nice article on various types
of
RF power measurement instruments and their uses. It appeared in a 1963 issue
of Electronics World magazine. The calorie wattmeter, calorimeter wattmeter,
photometric wattmeter, thermo-ammeter, RF voltmeter, reflectometer, in-line meters,
and slotted line are covered at a high level, without delving into the gory theoretical
details. Suggestions for selecting the proper instrument for measurement and operation
are touched upon. Although the article was written in 1963, many of these instruments
- or close descendants of them - are still in use today.
Monday the 30th
 Guglielmo Marconi is usually credited with
first employing radio waves for remote, wireless communications. In 1894 he reportedly
demonstrated a wireless signal transmission that rang a remote buzzer when a spark
transmitter was activated. He famously sent the first known transatlantic message
in 1901 from North America to Europe. Wireless between ships and shore had occurred
half a decade earlier over lesser distances. Russian historians beg to differ on
who should get credit for the first wireless communications.
Alexander Stepanovitch Popoff (aka Popov) supposedly beat Marconi in a number
of wireless benchmark transmissions and receptions by months or years. Popoff does
usually receive credit for having invented the automatic de-coherer...
 I found one more electronics quiz in a copy
of my vintage Popular Electronics magazine collection. Robert P. Balin
published scores of these quizzes over the span of a couple decades. Unless you
have created a few quizzes yourself, it might seem like there is nothing to it,
but even relatively simple ones like this requires the creator to think up the problems
and then guarantee that the answers given are correct. No, it's not rocket science,
but try creating a dozen quizzes with 8 to 10 questions; it could take a while.
Anywho[sic], this
Electronics Switching Quiz requires you to consider the switch positions and
then determine which lamps will turn on...
 "Not Touched by Human Hands" could be the
motto of DigiKey these days. The company has produced three videos so far to showcase
and boast about their fully
automated supply chain system. Amazon and other big-time product resellers are
well known for high levels of robotics and machine intelligence - much to the chagrin
of humans who would like to have jobs doing the work. Ever since Eli Whitney's cotton
gin displaced field workers, companies have sought to reduce labor cost and hassle
by automating processes. Many jobs can only be performed by humans, and many can
only be done by machines, with the vast majority lying somewhere in-between. The
videos are both inspiring and scary. Sure, you need people to design, install, and
maintain the automatons, but that is a very small number compared to opportunities
lost.
 Silicon controlled rectifiers (SCR) have
been around for half a century and are still workhorses in power control and switching
circuits. The SCR's usefulness comes both from being a diode with a settable forward
conduction point ("breakover voltage") and its property of continuing to conduct
below that threshold voltage once it has been reached. It then stays "on," acting
like a conventional bipolar junction diode until p-n junction is no longer forward
biased. At that point the diode is "off" again until the breakover voltage is once
again reached. When a sinewave is applied, as in a power supply design, this action
allows the SCR to be turned on for less...
 Alliance Test Equipment sells
used / refurbished test
equipment and offers short- and long-term rentals. They also offer repair, maintenance
and calibration. Prices discounted up to 80% off list price. Agilent/HP, Tektronix,
Anritsu, Fluke, R&S and other major brands. A global organization with ability
to source hard to find equipment through our network of suppliers. Alliance Test
will purchase your excess test equipment in large or small lots. Blog posts offer
advice on application and use of a wide range of test equipment. Please visit Allied
Test Equipment today to see how they can help your project.
Friday the 27th
 According to Wikipedia, "A sodium-sulfur
(NaS) battery is a type of molten-salt battery that uses liquid sodium and liquid
sulfur electrodes. This type of battery has a similar energy density to lithium-ion
batteries, and is fabricated from inexpensive and low-toxicity materials." They
have a high operating temperature (300-350 °C), with energy density of 300-400 Wh/L.
That was the type battery planned for use by Ford in an electric vehicle (EV). General
Motors, in this case, had "A Better Idea:" an EV version of its compact Corvair
car, aka the Electrovair, per this 1967 Popular Science magazine article. It was
to be powered by a silver-zinc battery (325-375 Wh/l)...
 If it has been a while since you read a
story with terms and phrases like "splinters
of galena," "the day of the tuning coil that stretched from the front bedroom
to the back library; or from the attic to the cellar," and "Ether God," then this
article from the December 1931 edition of QST magazine is for you. Galena,
by the way, is a semiconductor with a bandgap of about 0.4 eV that was used
as the crystal in crystal radio sets. It was used as a point-contact diode along
with a safety pin or similar sharp wire, commonly known as a "cat's whisker." In
fact, the very first transistor developed by Drs. Bardeen, Shockley, and Brattain
used two cat's whisker type contacts on their crystals of germanium...
 "Tsinghua University in Beijing began operating
its network in autonomous mode, also known as 'Level
4 network autonomy,' in September this year, I have confirmed. It's an impressive
achievement. But reader, I come bearing a second bulletin of autonomous network
news - and this one will cause a sharp intake of breath among Western comms vendors,
service providers and governments. China Mobile recently completed successful trials
of Level 4 autonomous networking in Guangdong province (population: 122 million)
and will begin its three-year program to deploy it nationwide in 2025. This is beyond
big - it is momentous. For perspective, Tsinghua University operates a not-for-profit
16,00..."
 Margaret LeFevre created a handful
electronics-themed crossword puzzles for Electronics World magazine
back in the 1960s. Crosswords have been around for at least two centuries and come
in many formats from having both x- and y-axis symmetry to symmetry about only one
axis or even no symmetry at all. They can be square, rectangular, or have special
shapes. This particular one has partial symmetry about the y-axis. Note that it
is composed of two isolated regions with no open path between the regions. If you
enjoy working crossword puzzles, there are plenty more which I have posted from
electronics magazines, plus I have created hundreds...
• Huawei
out to Recruit Western Research Talent
•
ARRL Straight Key Night: January 1, 2025
• Global
Smartphone Shipments Rise Again in Q3
• Silicon
Photonics Set for Takeoff
• Cambridge Engineers Set
938 Gbps Wireless Record
Thursday the 26th
 This little news item appeared in the "PS
Readers Talk Back" section of the January 1967 issue of Popular Science
magazine. It was submitted by Ronald L. Sefton, the Station Scientific Leader
at Byrd Station, Antarctica. He wrote to challenge a piece in an earlier edition
of the magazine which claimed another entity had the world's longest radio antenna.
According to Mr. Sefton, his outfit had both 21-mile-long and 10-line-long
VLF dipole antennas erected for experimental communications. It would be interesting
to know how the curvature of the Earth over that distance affected the radiation
pattern. A wire dipole supported above the ground at its end points would exhibit
a catenary shape curving downward in the center, but the wire lying on the curved
Earth would be more circular and curving...
 "Being
an
engineer in today's world is a very rewarding career experience, providing a
number of benefits and incentives for those employed full-time for a single company.
The advantages are usually in line with long-term career development, access to
resources, and financial stability. Having such a career eliminates the stress associated
with constantly looking for new projects and clients, and most reputable companies
allow for access to the latest tools, equipment, and software that may not be affordable
anywhere else. Of course, salary is the biggest draw when working at a single company.
Our recently conducted salary and career survey paints some pretty interesting numbers
when it comes to engineering trends. Those working in full-time positions have decreased
when compared to last year..."
 Just as modern high power semiconductor
amplifiers are composed of cascoded (connected in parallel) lower power amplifier
units, so too are
super-high-power vacuum tubes. In the case of tubes, a requisite number of triodes
(typically) are arranged around the perimeter of the tube enclosure with the inputs
and output connected to power dividers and combiners, respectively. In 1961 when
this article appeared in Electronics World magazine, there were no high
power semiconductors capable of outputting even kilowatts. Vacuum tubes are still
used in high power applications, although it is rare that you will find them with
glass enclosures; most are metal and/or ceramic. Over-the-air radio and television
broadcasting stations are major users...
 FM radio has been in the news fairly frequently
in the last couple years as phone manufacturers and the National Association of
Broadcasters lobby the FCC and politicians to mandate the inclusion of FM radio
capability into every phone manufactured (now extended to mandate AM radio in every
car). In a ploy to exploit the gullibility and egos of said bureaucrats and pols,
their primary argument that FM radio is a "first
informer in times of crisis," assuming of course that people will miss news
of "the big one" when and if it occurs. To my knowledge, successful reception of
FM radio on a cellphone requires the listener wear a set of wired ear buds since
the wire from the phone to the ear buds functions as the antenna. What percentage
of cellphone...
Wednesday the 25th
 Were strings of miniature Christmas tree
lights not available for purchase in 1955? This adventure of "Carl & Jerry" seems to imply that was the case since it concerns
the design and constructions of such a circuit using low voltage panel lamps (light
bulbs). Although usually the two techno-teenager are co-conspiring on various tasks
of high tech sleuthing or radio-related pursuits, but in this case if it Jerry who
has been doing the hard work. Author John Frye might not know how prescient he was
when describing the two inventions he conjured up for Carl and Jerry. The first
is the aforementioned miniature Christmas light string and the second is a voice
recording device that can capture a short message and then quickly play it back.
The playback scheme involves kids reciting their Christmas wish list to a fake Santa
Claus and then having him read it back to them in a different voice...
 The
Twin Paradox is a central thought experiment in Einstein's theory of Special
Relativity, vividly illustrating the phenomenon of time dilation. It involves a
scenario where one of two identical twins undertakes a journey into space at relativistic
speeds (approaching the speed of light), while the other remains on Earth. Upon
reuniting, the traveling twin is observed to have aged less than the twin who stayed
behind. This effect is not merely a theoretical curiosity but a real consequence
of the laws governing time and space. At the heart of the Twin Paradox is the relativistic
principle that time flows differently depending on an observer's frame of reference.
When objects move close to the speed of light, their passage through...
 At the end of World War II, the United
States government demonstrated an appreciation for the extreme sacrifices made by
its citizens by making surplus materiel available for purchase at very low cost.
Companies sprang up as distributors after bidding on and buying large lots of items
at auctions.
Herschel Radio Company was one of many. This 2-page advertisement on a 1948
issue of Radio-Craft magazine is typical of what was seen in all sorts
of technology publications in the late 1940s. A complete Fairchild model SCR 269/F
airborne radio compass was offered at a mere $75 ($998 in 2024 money). A Hallicrafters
model SX-28...
Tuesday the 24th
 Here are a few of my favorite
Christmas music videos.
They include an eclectic mix of Cloverton, the Trans-Siberian Orchestra, an unlikely
duet sung by Bing Crosby and David Bowie, and Casting Crowns. Watching the instruments
being played really enhances the effect of the song. I used to have the videos embedded
in this page for easy viewing all in one place, but each year on some of them I
have to go find new hosting location because the previous year's had been removed.
This time I am just linking to the YouTube (and other) web pages. The U.S. Air Force
Band performance at the Smithsonian Air and Space Museum is my newest addition...
 I was hoping that since these
electronics-themed comics appeared in December and January (1967 and 1968, respectively)
issues of Radio-Electronics magazine, they would have Christmas and/or
New Year subjects, but unfortunately that is not the case (these are being posted
on the RF Cafe website on Christmas Eve). Anyone who was around during the
vacuum tube circuits days will still relate to the page 92 and page 26
comics. Lots of opportunities existed for open or intermittent contacts with all
the connectors, tube sockets, and cold solder joints on terminals where point-to-point
wiring was done. While a lot of those issues...
 The inventors should look into selling knitted
"tinfoil hats" using this technique! "Imagine taking the radio frequency properties
of the dish antennas you see on rooftops and
knitting them into a wearable garment - a sweater or a blanket that is ultralight,
portable, easy to fold up and stow away. Not having to use heavy, bulky satellite
antennas would make communications much easier for those who live or travel in remote
locations - a lightweight, flexible antenna that can send information over long
distances would be a useful tool for both the public and private sectors. A Columbia
Engineering team reports that they have used their expertise in metasurfaces...
 Most
of us here in America recognize the
Packard Bell name from the line of personal computers they sold
in the 1980s and 1990s. I owned three of them, beginning with an Intel 80286 model,
then an 80486, and finally a Pentium model. They were in the "pizza box" format
that sat on the desk with the CRT monitor on top; I always preferred that configuration
over the tower type. Before Packard Bell made personal computers, they made personal
radios for the desktop beginning back in the 1930s. That explains why Mr. J.T. Goode,
an engineer with Packard Bell, would write an article in 1947 regarding a method
to tune antennas using light bulbs...
 Seeing an advertisement like this from a
national corporation - especially one that did work for the government - in a major
magazine would be rare these days. In 1945 when this Christmas advertisement was
proffered by
Jensen Radio Manufacturing Company in Radio News magazine, it was meant
as an inoffensive message of thanks and goodwill to all people, and particularly
to servicemen who had just fought a difficult and sacrificial war. Fortunately,
World War II would be over before the next Christmas came around. Today, some
would like to prosecute the purveyor for the crime of "hate speech," which is basically
anything suggesting America's founding was fundamentally righteous and just. "Merry
Christmas to all, and to all a good night!..."
 Withwave manufactures an extensive line
of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
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network analyzer (VNA) calibrator, between- and in-series connector adaptors,
attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner.
Special test fixtures for calibration and multicoax cable assemblies. Frequency
ranges from DC through 110 GHz. Please contact Withwave today to see how they
can help your project succeed.
Monday the 23rd
 When I read this account of relativistic
space travel by Dr. Wernher von Braun in a 1963 issue of Popular Science
magazine, I was a bit dubious about numbers he presented because they seemed to
me to assume a fixed value of relativistic speed during the entire round trip. It
is an example of the
Twin Paradox. Time dilation, as predicted by Einstein's theory of Special Relativity,
is barely noticeable at 10% the speed of light (0.1c), and is not really significantly
noticeable until around 30% the speed of light (0.3c), so I suspected that maybe
he had simplified the answer. His space ship example reached that speed at 3½ months
with a steady 1 G acceleration rate. Not wanting to go to the effort of figuring
it out for myself, I asked ChatGPT 4.0 to assess the article and render an
opinion...
 Here are eight
predictions for the semiconductor industry in 2025, per the IDC (International
Data Corporation). "1: Memory is expected to grow by more than 24%, mainly driven
by the increasing penetration of high-end products such as HBM3 and HBM3e with HBM4
expected to be introduced in H2. Non-memory is expected to grow 13%, driven by demand
for advanced node ICs for AI servers, high-end mobile phone ICs, and WiFi7. 2: Asia-Pacific
IC design market will grow 15% as inventory levels stabilize, personal devices demand
picks up, and AI computing extends to a wide range of applications. 3: Under the
traditional Foundry 1.0 definition..."
 A mere five years elapsed from the time
Echo, a gas-filled metallized plastic sphere that passively reflected radio signals
back to Earth, was launched and the time that 35
television cameras had been launched into space. The Space Race
was at a fever pitch. Although the Ruskies beat us in being the first to launch
both an active satellite (Sputnik) and a man (Yuri Gagarin) into space, America's
deep pool of intellectual resources, consisting of both native scientists and many
of the world's top scientists who chose to flourish in freedom here rather than
oppression behind the Iron Curtain, fostered the advantage that in short order established
the United States as the leading super power both in space and on terra firma. TIROS
satellites began providing real-time visual data on the Earth's weather in 1960.
Not only were cameras transmitting images of the Earth...
 An RF Cafe visitor sent this equation to
me a few years ago. It can be found all over the Internet (including here), but
I cannot determine a definite origin. Mathematicians claim that math can explain
everything in the universe, which is not quite true. It can't for example, explain
why my next-door neighbor is a junk hoarder. This
Christmas equation
does not appear to begin with a particular application; it looks like something
from a set of textbook end-of-chapter problems. Even if you don't celebrate Christmas,
it provides a secondary benefit by demonstrating rules for the manipulation of logarithms
and exponents along with basic algebraic rearrangements of terms...
 Merriam-Webster defines
Christmastide as "the festival season from Christmas Eve till
after New Year's Day or especially in England till Epiphany." In 1930 when this
article appeared in Radio-Craft magazine, most likely everyone knew what
Christmastide was, but not so much today. While reading and scanning vintage magazine
articles throughout the year, I set aside ones specific to holidays like Christmas,
Thanksgiving, Halloween, etc., and post them during their respective seasons. This
story is about the trouble caused by a well-meaning but unqualified family member
attempting to fix a radio that wasn't broken by gifting dear old Dad a Balkite trickle
charger (radiomuseum.org has one) for his battery-powered radio set. It also mentions
using a potato to test the DC polarity of a power supply or battery...
Friday the 20th
 Here is a very timely article entitled,
"Flying
Saucers - Myth or Fact?," which appeared in a 1964 issue of Radio-Electronics
magazine. The recent rash of unidentified flying objects over parts of New Jersey,
Wright-Patterson AFB, and a few other key locations has resurrected an interest
in whether "UFOs" exist. Despite hundreds of reports of what appear to be large
drones, the government insists they are not U.S. or foreign military equipment.
They specifically do not deny that they belong to some U.S. government agency -
like Homeland Security, FBI, CIA, etc. Conjecture that they are "nuke-sniffing"
drones searching for missing fissionable material. Regarding UFO video recordings,
have you noticed how with all the high tech cameras out there that there has never
been a clear, up-close picture of one? Those glimmering "orbs" in videos is clearly
the planet Venus in the evening sky right now...
 Salaries trend up for electrical and electronics
engineers in 2024 per this Electronic Design magazine survey
-- mine has been going down for years :{ "In
a tight labor market, skilled engineers continue to have leverage when negotiating
salaries and pushing for bonuses and other perks. In 2024, the median income of
electronics engineers and other tech professionals who responded to the survey is
in the range of $125,000 to $149,999. The survey revealed that slightly more than
20% of engineers expect to earn between $150,000 and $199,999, excluding bonuses,
overtime pay, and other earnings over and above their base salary...
 The
Yagi–Uda antenna,, often referred to simply as the Yagi antenna, was developed
in the late 1920s by Japanese engineers Hidetsugu Yagi and Shintaro Uda at Tohoku
University in Sendai, Japan. The primary motivation for their work was to design
a highly directional antenna capable of efficiently transmitting and receiving radio
waves over specific frequencies. This need arose as radio communications technology
was rapidly advancing, with an emphasis on improving signal strength and selectivity
for applications in research and burgeoning communication systems. Mssrs. Yagi
and Uda sought to enhance the performance of basic dipole antennas by creating an
array that exhibited improved directivity and gain. ..
 Margaret LeFevre created a handful
electronics-themed crossword puzzles for the July 1961 issue of
Electronics World magazine. Crosswords have been around for at least two
centuries and come in many formats from having both x- and y-axis symmetry to symmetry
about only one axis or even no symmetry at all. They can be square, rectangular,
or have special shapes. This particular one has partial symmetry about the y-axis.
Note that it is composed of two isolated regions with no open path between the regions.
If you enjoy working crossword puzzles, there are plenty more which I have posted
from electronics magazines, plus I have...
• Kids Can
Talk to Santa via Ham Radio
•
Cellphone Radiation Linked to Brain Cancer
• EU Gives
€127M
Funding Boost to 6G Research
• Q3 Foundry
Revenues up 27% Y-o-Y
•
TSMC Panics When Identified Huawei Chip Maker
Thursday the 19th
 By the time editor Hugo Gernsback wrote
his "Electronic
Failures in Space" article for the April 1964 issue of Radio-Electronics
magazine, half a decade had passed since the official end of the International Geophysical
Year (which was actually 18 months long). Much new knowledge had been gained and
theories confirmed regarding the environment electronics would be exposed to not
just while above the atmosphere, but also while passing through it. Oh, and the
extreme vibration and acceleration during the launch and boost phases to get into
space were no piece of cake to accommodate, either. Fortunately, a lot of immensely
smart and dedicated people worked out the bugs one by one, and we have arrived at
a vastly advanced...
 "Arizona State University (ASU) in the USA
reports on high-voltage aluminum nitride (AlN) metal–semiconductor field-effect
transistors (MESFETs)
on single-crystal AlN substrates. The researchers claim their work as the first
report of 'AlN transistors via homoepitaxial growth on native substrates.' The team
comments: 'The devices showed good saturation and pinch-off behavior with high maximum
Ids, gm and on/off ratio compared with AlN-on-sapphire devices without complicated
contact layers.' AlN has the highest breakdown electric field, 12MV/cm..."
 The history of growing
semiconductor boules is a cornerstone of modern electronics, marking advancements
in material science and technology that have propelled numerous industries. Boule
growth processes have their roots in the early 20th century, when researchers first
sought to create pure semiconductor materials for experimental purposes. Initially,
materials such as germanium (Ge) and silicon (Si) were used, with silicon ultimately
becoming the most prevalent due to its superior properties and availability. Germanium
was the first material used extensively in semiconductor applications, as its electronic
properties made it suitable for early transistor designs. The Czochralski process,
developed in 1916, was adapted for germanium and later silicon. This method, involving
the slow pulling of a seed crystal from molten material, remains fundamental to
boule growth today. Silicon's dominance...
 Side-looking airborne radar (SLAR) started
out using a narrow beam formed by reflectors, like traditional radars, as opposed
to the synthetic aperture type most often used today. Both types of side-looking
radars rely primarily on the physical movement of the airborne platform for effective
azimuthal scanning rather than steering the beam either mechanically or electronically.
This 1965 Electronics World magazine article represents early versions
which used "real aperture" antennas. Modern computer-controlled synthetic aperture
radar beams can be segmented and directed off-axis for detected...
Wednesday the 18th
 Did I ever bore you with my experience building
a crossover network for a set of medium power speakers (about 100 watts each) when
in the USAF? Too bad I didn't have this "How
to Build a Crossover Network" article from a 1968 issue of Radio-Electronics
magazine handy. I'll spare you the details, but the era was 1979, and I was in tech
school at Keesler AFB studying to be an Air Traffic Control Radar Repairman. Being
amped up (pun intended) with electronics theory with both semiconductor and vacuum
tube circuits, I was looking to cobble together a nice amplifier and a set of speakers.
Back in the day, it was possible to buy the components...
 San Francisco Circuits, a premier provider
of leading edge technology printed circuit boards, has published a new article on
the
Immersion Silver Surface Finish process, also known as immersion Ag. It is an
RoHS compliant (lead-free) PCB surface finish offering exceptional flatness and
cost efficiency. This surface finish is particularly well-suited for fine-pitch
components and can replace Immersion Gold over Electroless Nickel (ENIG) in many
applications. Unlike ENIG, Immersion Silver applies directly to copper without requiring
a diffusion barrier. It's an excellent choice for applications that must avoid magnetic...
 Here are a couple
high tech comics for your enjoyment from the pages of the July 1961 edition
of Electronics World magazine. I'm guessing the joke in the page 72
comic is that unknown parts were/are generically referred to as "Brand X," so hopefully
that would bring in customers who couldn't identify components (which the repairman
probably could). The page 94 comic is yet another play on the huge popularity
of home hi-fidelity (hi-fi) sound systems of the day. Amplifiers still used vacuum
tubes so building speaker driver circuits that could handle hundreds of watts was
easy to do. Finding speakers to handle that power (and getting neighbors to tolerate...
 In case you are wondering, here is how you
would write "Merry Christmas and Happy New Year" in the world's most prominent languages.
While not everyone celebrates the birth of Jesus, most recognize the holiday spirit
during what we call the Christmas Season. This image includes the same hopeful and
grateful message to everyone. Thanks to all of you who has helped make RF Cafe
a success since 1999!
 At the prompting of others, I decided to
give podcasting a try. Having been
advised that I have a face for radio and a voice for print, there was some hesitation
on my part. However, there have been many fine articles published in vintage electronics
magazine that people might be willing to listen to when there is no opportunity
or desire to read them. Regular features such as "Carl & Jerry," "Mac's Radio
Service Shop," editorials by the great Hugo Gernsback, and other types that do not
contain images which need to be referred to in order to get the gist of the content,
are prime targets for podcast listening. If the podcasts prove to be popular enough,
I will expand to a paid subscription...
 KR Electronics has been designing and manufacturing custom filters
for military and commercial radio, radar, medical, and communications since 1973.
KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop,
equalizer, duplexer, diplexer, and individually synthesized filters for special
applications - both commercial and military. State-of-the-art computer synthesis,
analysis, and test methods are used to meet the most challenging specifications.
All common connector types and package form factors are available. Update: KR Electronics
has been acquired by NIC, where KR Electronics'
legacy of quality and innovation will continue to thrive, offering the same trusted
products and services under NIC's leadership. For over three decades, NIC has delivered
high-quality component performance and reliability, ensuring the successful deployment
and operation of our clients' mission-critical solutions. Designed and manufactured
in the USA. Please visit NIC today to see how
we might be of assistance.
Tuesday the 17th
 Another
triplet of electronics circuit challenges here for you from a 1962 issue of
Radio-Electronics magazine - a resistor network, a voltage divider, and
a delayed switching circuit. As is usually the case with the resistor network, rearranging
the circuit branches into a more familiar configuration simplifies its analysis.
That is a good general rule when analyzing any circuit - rearrange and break down
into recognizable subcircuits. The series circuit is about as simple as it gets,
but knowing about how an ammeter is constructed helps. The Delayed Switching challenge
is a little misleading in its description since the proposed solutions does use
a vacuum tube duo diode (aka dual diode or full-wave diode) as part of the power
supply circuit, although...
 As our traditions are besieged by malcontents
determined to denigrate, impugn, and ultimately erase memories of holidays and events
that have meant so much to families and friends, I feel compelled to resist the
movement by documenting parts of the past that will cause us to wax nostalgic over
our cherished traditions. Intimidation and violence is part of the strategic calculus;
we have seen it in spades in 2020, and 2021 promises to be even worse. The Cancel
Culture might eventually win out with the complicity of government agents both elected
and unelected, but I'm not going down without a fight. Here is a collection of twentieth
century, December issue
QST magazine covers with Christmas themes that will no doubt be
familiar to many of you. Finding them was more difficult...
 John T. Frye, born on March 14, 1910 and
passing on January 31, 1985, was a celebrated author, electronics enthusiast, and
technical writer whose work left an indelible mark on the world of radio and electronics.
According to historical records, he was stricken with polio as an infant, which
left him physically disabled and confined to a wheelchair. Despite this early adversity,
Frye demonstrated extraordinary perseverance and creativity, becoming one of the
most prolific and beloved contributors to technical literature during the mid-20th
century. John T. Frye's career as a writer began to flourish in the 1940s and 1950s,
when he penned numerous articles, instructional guides, and serialized stories that
combined entertainment with education. Among his most iconic works were the Carl &
Jerry stories, which ran for many years in Popular Electronics magazine...
 "Unknown drone activity forced one of the
U.S.'s most critical military installations to shut down for several hours late
Friday evening and Saturday morning, officials confirmed. The incident prompted
heightened security measures and temporarily
halted operations at Wright-Patterson Air Force Base in Ohio. Home to the 88th
Air Base Wing, Wright-Patterson is one of the largest and most strategically important
bases in the U.S., tasked with advanced research, intelligence, and operations.
Unauthorized drone activity in military airspace poses significant risks, from espionage
to safety hazards. In audio recordings by the Air Force Base air traffic control,
which were shared online, an operator can be heard saying they are diverting 'over
base' air traffic..."
 "Q" is an often used term to describe the
electrical "quality" of a circuit or component, and for the most part anyone
engaged in the conversation (verbally or via reading) understands the concept. However,
having a firm grasp on the technical ramifications is required if you happen to
be a circuit or system designer and need to conform to certain specifications. "Q"
can be good or bad, depending on your needs. If, for example, you need a narrowband
receiver to reject adjacent signals or you are designing a high stability and spectrally
clean oscillator, then you want all the "Q" you can get. On the other hand, if your
goal is to receive a spread spectrum signal or generate white noise across some
bandwidth, then a lower "Q" is what...
 Innovative Power Products has been designing
and manufacturing RF and Microwave passive components since 2005. We use the latest
design tools available to build our baluns, 90-degree couplers, directional couplers,
combiners/dividers, single-ended transformers, resistors, terminations, and custom
products. Applications in military, medical, industrial, and commercial markets
are serviced around the world. Products listed on the website link to detailed mechanical
drawings, electrical specifications, and performance data. If you cannot find a
product that meets your requirements on our website, contact us to speak with one
of our experienced design engineers about your project.
Monday the 16th
 Whoa! John T. Frye really outdid himself
in dreaming up a Rube Goldberg electronics contraption in this 1960 "Improvising"
episode of his
Carl and Jerry technodrama series in Popular Electronics magazine.
I have wondered whether he actually proves these concepts by building what he describes
the boys doing; it wouldn't surprise me if he did. Even if the devices are purely
theoretical, the description of the thought process and method of practice is impressive.
This being the beginning of the snow season in the northern realm, the story's setting
in a crippling snow storm is timely. It was potentially a life-or-death situation,
which triggered the classic "necessity is the mother of invention" reaction...
 Even
in this age of a prodigious supply of computer programs and mobile device apps (OK,
apps are also computer programs) to calculate circuit component values and responses,
having a cool graph to look at can take a lot of mystery out of the results. Depending
on the sophistication of your software, calculated values can be unrealizable in
real life (size, power handling, standard values, Q, operational frequency, etc.),
or maybe you have a box full of parts you want to use and the suggested value is
not readily available. In those instances and others, being able to grab a handy-dandy
design chart to see where component values lie with respect to all design parameters.
In this 1963 Electronics World magazine article, author A.L. Teubner
describes the process for using his
ripple filter graph and provides an example...
 "Google's quantum computing breakthrough
on Monday has left the physicist who heads the project a believer in 'the idea that
we live in a multiverse.' 'Willow,' the tech giant's new quantum chip, succeeded
in
solving a computational problem so complex it would have taken today's best super-computers
an estimated 10 septillion years to solve it - vastly more than the age of our
entire universe. But Google said its new quantum computer solved the puzzle 'in
under five minutes.' Calling Willow's performance 'astonishing,' the leader and
founder of Google Quantum AI team, physicist Hartmut Neven, said its high-speed
result 'lends credence to the notion that quantum computation occurs..."
 Crossword puzzles have probably lost their
appeal to most people - especially if they are on paper and not in electronic format
that can be worked on a computer (your smartphone is also a computer, BTW). 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...
 Over
the last year, I have been interacting with ChatGPT AI engine quite a bit, in order
to ascertain its usefulness and trustworthiness. A mix of response quality has been
received, but most inaccuracies on the part of Chat GPT have been due to imprecise
queries on my part. The key to success is concisely forming your query, including
detailed requirements about the output if required. My latest query prompted
ChatGPT for Top 10 lists for typical user on various topics. Here are the results...
 According to this 1972 article in Popular
Electronics magazine, there were as many as 50,000 computers in the world at
the time using
magnetic core memories. Among them was the Apollo Guidance Computer that was
onboard the Apollo 11 Lunar Module that Neil Armstrong used in July 1969 to
land on the moon. Semiconductor memories were being manufactured in 1972, but believe
it or not they were not as fast as the magnetic core memories. Machinery was not
available with enough precision and repeatability to thread the read, write, sense,
and inhibit wires through each ferrite core. The TPX-42 IFF secondary radar I worked
on in the USAF had a 1 kByte magnetic core memory. Small women with small hands
were...
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
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