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 Are you having a rough week? If so - and
even if not - take a few minutes to get a laugh from these
electronics-themed comics from the pages of vintage Radio
News magazines. Beginning sometime in the late 1930s and early 1940s, single-panel
topical comics began appearing frequently in many hobby and even professional magazines.
Sure, comics showed up in magazine before that time, but they generally did not
necessarily have to do with the main subject of the publication. The Saturday
Evening Post, for example, had many single-panel comics, but they were on any
random theme. The Saturday Evening Post, for example, had many single-panel
comics, but they were on any random theme. I can't go without commenting on the
April 1946 comic since it reminds me of a situation...
 Arthur Hackman's 1967 Electronics World
magazine article provides a systematic guide for
selecting mechanical and manual switches, beginning with specifying the required
function through poles (circuits controlled) and throws (positions connected, excluding
"off"). Voltage and current ratings must not be exceeded to prevent contact welding
or catastrophic dielectric failure. Mechanically actuated switches include pressure-sensitive
types (with defined proof and burst pressures), temperature-sensitive switches,
and various limit switches (plunger, lever, roller), which require consideration
of mounting and environmental sealing for harsh conditions. Manually...
 Isn't an anagram a word game where letters
of one word are rearranged to spell another word or series of words? For instance,
an anagram for "microwave" is "warm voice," one for "resistance" is "ancestries,"
and for "vector" is "covert." If so, then this puzzle is misnamed; it is really
a crossword puzzle. Maybe back in 1961 the word anagram included this type of puzzle.
Regardless of the naming error, I did learn a new word: "inertance," which means "the effect of inertia in an acoustic
system, an impeding of the transmission of sound through...
 "Electronics have long been defined by their
permanence. Even when their useful life ends, their materials persist in landfills
for years or decades.
Transient electronics embrace impermanence with devices that are deliberately
engineered to function for a set period of time and then disappear, dissolving into
safe byproducts when exposed to water, heat, or light. Advances in electronics technology
moving at a faster pace than ever before, and, thus, older electronics become obsolete
or undesirable quickly. While there are obvious benefits to developments in electronic..."
 Magnetostriction is a term not seen very
often these days. It describes the physical shape change that takes place in certain
ferrous materials when subject to a magnetic field, and is responsible for most
of the familiar "hum" that comes from transformers. The effect is used in mechanical
filters as transducers between the electronic circuit and the mechanically resonant
disks that define filter bandpass characteristics. Elemental cobalt exhibits the
highest room temperature magnetostriction (units are "microstrains"). Nickel, with
about half the value as cobalt, is cheaper and more abundant and is therefor more
commonly used in modern magnetorestrictive transducers. Way back in the 1980s while...
 RF Cafe's spreadsheet-based engineering
and science calculator,
Espresso
Engineering Workbook™, is a collection of electrical engineering and physics
calculators for commonly needed design and problem solving work. A Transformer
Calculator worksheet has just been added, making for a total of 45 calculators.
It is an excellent tool for engineers, technicians, hobbyists, and students. Equally
excellent is that Espresso Engineering Workbook™ is
provided at no cost, compliments of my generous sponsors...
 There was a time when having a career in any
field of electricity or electronics work was an enviable mark of a person's technical
prowess that conveyed a degree of respect. The whole
controlling of electrons thing boggled the minds of most people,
whether it meant wiring homes and buildings for lights, receptacles, and motors,
or designing "all wave" radio sets for listening to the evening broadcast of "The
Lone Ranger." Today, with nearly everyone alive having grown up with such conveniences,
the "wow factor" is pretty much gone, except maybe with those of us who still chose
to engage. If an electronics appliance...
 Substitute "cellphone" for "radio" in this
title ("Money
in Radio Gadgets"), and editorial by Hugo Gernsback and it would fit right in
with today's market of wondrous gadgetry. Prescient as always, Mr. Gernsback describes
in this 1933 issue of Radio-Craft magazine, among other things, what we now refer
to as energy harnessing to power ancillary devices and props. He also recommends
a scheme for causing "dancing dolls" on the surface of a table vibrated and mobilized
by the sonic waves of a large speaker - a lot like the way years later vibrating
football games were made (remember them?) where the men danced randomly across the
painted metal playing field. It sounded like a pair of electric...
 "Researchers at the Hebrew University of
Jerusalem have found that the
magnetic
component of light plays a direct part in the Faraday Effect, overturning a
180-year belief that only light's electric field was involved. Their work shows
that light can exert magnetic influence on matter, not simply illuminate it. This
insight could support advances in optics, spintronics, and emerging quantum technologies.
The team's findings, published in Nature's Scientific Reports, show that
the magnetic portion of light, not only its electric one, has a meaningful and measurable
influence on how light interacts with materials. This result contradicts..."
 This
passive
RF limiter is a simple combination of cascaded "T" type resistive attenuators
that are switched in and out of the circuit based on the power level in the line.
The design takes a bit of thinking due to needing to retain a reasonable impedance
match at the input and output throughout various stages' conduction states. Arriving
at an optimal value for resistors would require a circuit simulator with a mathematically
based optimizer, but, especially for amateur radio work, close is good enough. That
is not to say Hams are a bunch of slackers - they're not - it's just that component
and software resources are not as readily available (aka "prohibitively expensive")
for doing the analysis and testing. In 1966 when...
 This
Electronic Crosswords puzzle appeared in the October 1963 edition of Electronics
World magazine. About half the words used are related directly in some way
to electronics or physics. It's a fairly small puzzle so it shouldn't take you too
long to complete. My RF Cafe crosswords, by the way, have 100% of the words directly
related to the sciences, from a custom lexicon I have created over 20 years of making
puzzles. Enjoy...
 Avalanche breakdown in semiconductors, initially
viewed by engineers as a destructive limitation, was later discovered to be nondestructive
when peak power was controlled through external circuitry. This 1967 Electronics
World magazine article explains how
avalanche transistors evolved from being considered problematic to becoming
valuable components for high-speed pulse generation. Early adoption was hindered
by inconsistent performance between transistors, requiring careful selection for
reliability. Improved fabrication techniques reduced surface leakage currents, enabling
modern avalanche transistors to operate at high collector voltages...
 Until maybe 30 to 40 years ago, there was
still a certain amount of awe associated with new applications of technology. It
seems anymore people are so accustomed to new and amazing things - usually at affordable
prices - that the wonder is gone. Advancements are expected. The world is moving
so fast that it is difficult to absorb and fully appreciate all the work being done.
In 1947 when this "Sound
Broadcasting from Airplanes" article appeared in Radio News magazine,
both airplanes and electronics were still relatively new to a lot of people, especially
in more rural areas, so a whiz-bang scheme like broadcasting messages from an airplane
was a big deal to many. It was an area of science that had not yet been explored
to a large degree. BTW, the spell checker flagged a new word (for me, anyway): genemotor
which, as it turns out, is the generic name for the line of dynamos, generators,
engines, and motors manufactured by Pioneer Gen-E-Motor Corporation of Chicago,
Illinois...
 "Inside a secure facility overseen by the
Central Science and Technology Commission, Chinese engineers have activated an
Extreme Ultraviolet (EUV) lithography machine - a technology the U.S. spent
years attempting to block. A recent Reuters investigation confirms the EUV prototype
is now operational in Shenzhen. This development is not just a technical milestone;
it is a seismic structural realignment that effectively marks the end of the unified
global semiconductor market. Lack of access to the leading edge technology of ASML's
EUV lithography machines. Strict 'small yard, high fence' restrictions would keep
China several generations behind in technology..."
 Remember when you could hold a telephone
conversation without having to allow a moment of time at the end of a sentence before
responding in order to keep from "stepping on" the person on the other end? It used
to be only overseas phone calls or maybe communicating to astronauts on the moon
suffered such inconveniences, but talking to someone across town was like having
a face-to-face discussion. More often than not - or so at least it seems - there
is a noticeable delay between the time someone actually stops talking on the transmitter
end and the time the audio stops at the receiver end. People who have never known
otherwise accommodate the delay with no appreciation for how good phone calls used
to be. This promotion by
Bell
Telephone Labs which appeared in a 1946 issue of Radio News magazine
extolls the virtues of its "scientific quality control" innovation that produced
repeatable...
 In 1935,
not much was yet known about the
ionosphere. Its existence was first theorized in 1902 by Arthur
Kennelly and Oliver Heaviside, and Edward Appleton proved its presence in 1924 by
conducting a series of broadcast experiments, but no direct measurements were possible
until rocket-borne instruments could be launched. An Aerobee-Hi sounding rocket
was launched in 1956 as part of the International Geophysical Year (IGY) project
that made the first actual detection of ionized particles in what is now referred
to as the D-layer. It is therefore forgivable that Hugo Gernsback, normally spot-on
in his theories and postulations regarding RF propagation, incorrectly suggested
in this editorial that based on observed time...
 This 1967 Electronics World magazine
article highlights a potential revolution in microwave technology through new semiconductor
devices that could miniaturize and drastically reduce the cost of microwave sources.
The focus is on two promising devices: the Read p-n junction diode and the
Gunn bulk gallium arsenide oscillator. The Gunn device, discovered accidentally
by Dr. J.B. Gunn at IBM, operates on a radical principle - a bulk semiconductor
material oscillates at microwave frequencies without external tuned circuitry when
a threshold voltage is applied. Key to the Gunn effect is the unique property of
gallium arsenide, which features a second conduction band. Electrons entering this
high-energy, low-mobility band create "domains" that drift slowly from cathode to
anode, causing current...
 Most people have heard of the incredibly
accurate
Norden bombsight that was credited for revolutionizing accuracy
of heavy bombers like B-17s, B-25s, and B-29s. It was an electromechanical device
that took bombardier inputs of altitude, airspeed, heading, and wind speed and direction,
then calculated the impact point of the bomb. An accuracy of 75 feet was claimed
under ideal conditions - provided by a mechanical computing device. By 1956 when
this article was published, the Norden had been replaced by radar-integrated bombing
systems. Additionally,
ground-based radar measurement systems were...
 "On
Monday, December 22, 2025, the FCC released
DA 25-1086,
which adds
foreign-made drones and some components to security risk list. What the decision
actually means: "If you already own a DJI or other foreign-made drone, you can still
fly it. Stores can still sell previously approved models while inventory lasts.
New foreign-made drones and key components can no longer get FCC approval. In practical
terms, future DJI models are now cut off from the U.S. market. There are no true
low-cost, one-for-one replacements available today..."
Most people have heard of the incredibly
accurate
Norden bombsight that was credited for revolutionizing accuracy
of heavy bombers like B-17s, B-25s, and B-29s. It was an electromechanical device
that took bombardier inputs of altitude, airspeed, heading, and wind speed and direction,
then calculated the impact point of the bomb. An accuracy of 75 feet was claimed
under ideal conditions - provided by a mechanical computing device. By 1956 when
this article was published, the Norden had been replaced by radar-integrated bombing
systems. Additionally,
ground-based radar measurement systems were...
 If you need a cheap, quick
lightning arrestor for your antenna or just about any type of
wired system, this idea from Mr. Burgess Brownson looks like a good option.
He used an automotive spare plug. Voltage breakover points can be set by varying
the spark gap distance. The old vacuum tube transmitters and receivers had a better
of chance of surviving a lightning strike because the components were able to handle
much more of a shock than our modern semiconductor sets with miniature, closely
spaced components. Still, the spark plug setup is better than nothing, if for no
other reason than to protect the shelter. it should suffice. This and many
...
 Aircraft electronics has always been on
the bleeding edge of technology because of the ever-increasing need to fly in the
widest range of atmospheric conditions possible. Accordingly, skills needed by avionics
servicemen are amongst the highest required in any electronics field. There are
still many pieces of vintage equipment in service that need to be maintained, but
even 20- to 30-year-old airborne radars and navigational units require top-notch
techs to troubleshoot and align. One topic in particular that plagues electronics
operation even in modern airframes is that of static electricity build-up and lightning
strikes. We all face those kinds of static discharge hazards in non-aviation environments,
but for the most part a failure on the ground or water is not as imminently...
|
 • U.S.
Cuts EV Plans as Tax Credit Ends
• Fragmented 6 GHz Policy
Shapes Wi-Fi 8 Adoption
• Big 3 Have
Room for 32M FWA Customers
• FCC Simplifying
Broadband "Nutrition Labels"
• GSMA Pleads for
Yet More 6G Spectrum
 The
RF Cafe Homepage Archive
is a comprehensive collection of every item appearing daily on this website since
2008 - and many from earlier years. Many thousands of pages of unique content have
been added since then.
 Homepage
Archives for October 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.
 RF Cafe visitor Mike M. reminded me
of "Madman Muntz,"
who was a widely known television commercial personality on the West Coast from
the 1950s through the 1970s. Earl William "Madman" Muntz's zany live and animated
commercials were used highly successfully in selling cars, including one he himself
designed and manufactured called the Muntz Jet. Along with being a master salesman,
Madman Muntz was also a self-taught electronics engineer of sorts. He is credited
with developing the first 4-track stereo tape deck for cars, which was a precursor
to the 8-track tape deck. What Mike mentioned specifically was the line of Muntz
television sets. Not satisfied to merely manufacture TV sets, Muntz created an entire
service shop and fleet of mobile television trucks. It was kind of an early version
of the Nerd Herd. Based on the Madman's trademark method of minimizing the number
of components used in his products...
 This "The National QSO Page" editorial from
the December 1938 issue of Radio News magazine really took me by surprise. Evidently
there was a rift with amateur radio operators over whether Radio News was
attempting to
overthrow the American Radio Relay League's (ARRL) dominance in the Ham realm.
At the time, the ARRL had only been in existence for 24 years. There had been some
previous criticism of the ARRL for not sufficiently (in Radio News' opinion)
defending access to dedicated Ham spectrum and legal transmit power levels, and
also for the ARRL counting among its membership anyone who subscribed to the organization's
QST magazine. The former point is arguable, but the latter seems rather
petty since likely the percentage of subscribers who were not ARRL members, too,
is probably very small. Interestingly, Radio News accused the ARRL of being weak
lobbyists in Washington...
 Finding current information on the ARRL's
Brass Pounders
League (BPL) is difficult, and in fact a search on the ARRL.org website does
not get you to a page with a date more recent than around 2012. I don't know whether
the BPL has been "obsoleted" or just does not enjoy the promotion level it once
did. This article in The Dipole publication reviews a bit of the history
of the Brass Pounders League, and even mentions Mary A. Dougherty (a.k.a Mae Burke,
W3CUL), who is featured in this 1953 QST article. She was born in 1911 and became
a Silent Key in 1997. If I wasn't so busy, I would do some research to find out
what the percentage of licensed female Hams was in 1953 compared with today. I wouldn't
be surprised if the number was higher in 1953...
 Here for your almost-Friday enjoyment is a collection
of
radio-themed comics from a 1964 issue of Popular Electronics
magazine. The scenario in the first comic is one that an owner of an antiques
store told me happens often with cunning customers. Now that eBay has been
around for so long, shop owners, yard/garage sale holders, Craigslist sellers,
and even places like Goodwill know what their items are really worth and price
accordingly. In fact, about the only things you can find at those venues anymore
is utter junk or stuff too big to sell and ship on eBay - like an area rug or a
night stand. Every once in a while you'll come across a good deal when the
person is not Internet savvy, but not often. We hardly even look anymore...
 When designing a receiver or transmitter
using discrete components rather than connectorized components or packaged integrated
circuits, where the interfaces are at or near 50 + j0 Ω, adding frequency selectivity
beyond that provided by the generic response requires inserting separate filters.
If you are designing the entire signal path, including the biasing, feedback (if
any), and stage interfaces from scratch, you can include features that increase
frequency selectivity. In the "old days" with vacuum tubes and interstage coupling
transformers being commonplace, the addition of a few
capacitors made response peaking a simple advantage to implement. The National
Company frequently advertised in QST magazine to appeal to Hams with their extensive
line of radio wares...
 My favorite of this collection of
vintage electronics-themed comics is the one from page 186. Watching someone
involuntarily jump from being pranked is great fun, and I'll admit to being easily
spooked by such actions. Stop me if I've told this story before, but back in my
electrician days in the 1970s (before enlisting in the USAF) we were always trying
to make each other jump from thinking something happened to cause a spark or some
sort of electrical noise. If you've ever heard the sound a screwdriver makes when
accidently bridging the main service bus and ground of a circuit breaker panel,
then you know it's not always the loud "buzz" you hear when a small arc is occurring.
It sounds like a hammer slammed against the wall (trust me, I know). One of the
things we liked to do, especially to new guy, was while he was installing a switch
or receptacle into a wall box was to go on the other side of the wall and bang on
it with a hand or pair of lineman's pliers (in a manner that wouldn't harm the wall,
of course). The poor sap often would yell and fall backwards...
Anytime I see a photo or story about the
1964 New York World's Fair, I immediately think of the scene at
the end of the first "Men in Black" movie when Agents K and J face off with the
alien invader who has come to Earth in search of "The Galaxy." This story from an
April 1964 issue of Electronics magazine reports on preparations made for
the grand opening on April 22 of that year. Based on the typical three to six month
lead time for publishing magazines back in the day, this material would have been
gathered long ahead of time. Of course now that half a century has passed we hardly
consider any of the whiz-band technology presented there as being anything wonderful,
but then half a century from now our grandkids will laugh at what we consider amazing
at the present time. Here is an interesting statement from the article that really
gives you an idea of generational progress: "The World's Fair alone will contain
some 300 television..."
 Electronics symbols
for schematics and wiring diagrams have remained amazingly consistent for the last
hundred years, although obviously many new ones have been added. You can see from
this set of standardized wiring diagram and schematic symbols from a 1955 edition
of Popular Electronics what I mean. Even symbols for newly introduced devices tend
not to change. There are some variations such as whether or not to draw a circle
around a transistor or how many lightning bolt lines to use with photon emitters
and detectors, but that's about it. The digital world adopted IEEE Standard 91-1984
for logic and microprocessors, although you will still occasionally see variants
in symbols, especially in early digital circuit schematics. The ARRL publishes its
own version of standardized electrical schematic symbols, but even the ARRL
Handbook, in which the symbols are printed, does not strictly conform to its
own standards.
 Bypass capacitors play a vitally important
role in electronic circuit design. Many people do not know the proper way for deciding
which capacitor or capacitors is/are needed for effective noise and/or signal bypassing
without either overdoing or underdoing it. Needs change over the years as frequencies
and signal characteristics occupy new realms of the spectrum. A Fourier analysis
of some of today's complicated waveshapes for switching power supplies shows how
sometimes tailored responses to bypassing is required. This article from the January
1962 Popular Electronics magazine does not delve into the intricacies of complex filters,
but it does provide a nice introduction to the need for bypassing and how to stand
a good...
 Parenthetically mentioned in this introductory
article on lasers is a "Mie" type particle. At first I thought maybe it was a typo,
but in fact it refers to
Mie scattering, which is the dispersion of electromagnetic waves
by isolated spheres, stratified spheres, infinite cylinders, or other geometries
where radial and angular dependence are independent. Two simple experiments are
described for demonstrating light scattering and absorption similar to what occurs
in the atmosphere. Whereas procuring the 2.5 mW laser source and to a lesser
extent suitable light meter would have been difficult and expensive in 1971 when
this was published in Radio-Electronics magazine, today's cheap equipment
puts them within the budgets of almost anyone. Many of the <$10 cat toy lasers
provide plenty of power...
 Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed
crossword puzzle using only words from my custom-created lexicon related to
engineering, science, mathematics, chemistry, physics, astronomy, etc. In this crossword
for June 14th you will never find among the words names of politicians, mountain
ranges, exotic foods or plants, movie stars, or anything of the sort. You might,
however, see someone or something in the exclusion list who or that is directly
related to this puzzle's theme, such as Hedy Lamarr or the Bikini Atoll, respectively.
Enjoy!
 Here's a little dose of Ham comedy to help
take the edge off a busy day - straight from the ARRL's QST magazine in
a piece entitled, "Blonde QRM." It's
a little bit kooky by today's standards, but in 1940 the style of humor it fits
right in. This could easily have been the plot in an old TV show like The Honeymooners,
or one of the radio sitcom programs like The Life of Riley. It reminds me of how
in the "Nancy Drew Detective," movie from the 1930s, Ted is a Ham radio operator,
and he tells his fellow Ham that he has experienced "local QRM" when Nancy Drew
suddenly enters his shack (Nancy is a blonde). QRM, by the way, is Ham lingo for
man-made signal interference, as opposed to QRN, which is atmospheric or "natural"
signal interference...
 There are few better ways to wind down
a work week than with some good old-fashioned (literally)
technology-themed comics. This three fifths of a handful of comics
appeared in a 1944 issue of Radio News magazine. You need to know when looking at
these scenarios that people in the 1940s cherished and revered their radio sets
like people today do with their cellphones. Magical and supernatural attributes
were assigned to them by some, especially the non-technically inclined. Entire families
gathered around the radio in eager anticipation of the latest episode of "The Shadow,"
The Lone Ranger," "Little Orphan Annie," "Jack Benny," and "Inner Sanctum Mystery."
BTW, if you want to experience the aura of old time radio shows, many of them are
available for listening online on the Old Time Radio Catalog website and others...
 These
tech-themed comics appeared in a 1964 issue of Radio-Electronics magazine.
Servicing entertainment electronic systems was a big thing in the day, as evidenced
by many of the comics posted here over the past few years (see huge list at bottom
of page). The comic on page 50 shows an oscilloscope display that was not probable
before digital test equipment came to be. It was possible to generate such a waveform
on a cathode ray tube (CRT) face as a reference image, but it would require very
sophisticated circuitry. There were special applications - like air traffic control
plan position indicators (PPI's) - where pains were taken to be able to add annotation
to the display (e.g., aircraft IFF data). A common method for superimposing fixed
references (such as the music scale here) was to add a composite video signal that
was added in with the sampled signal. It is the opposite of devising a scheme to
add o-scope type video to a standard raster scan TV picture. The page 82 comic is
interesting because it depicts a Ham cogitating...
 These interactive maps were created by the
FCC to illustrate the Commission's broadband and cellular deployment results. The
original was found in the Eighth
Broadband
Progress Report which uses data underlying the National Broadband Map, as of
June 30, 2011. It shows census block areas of the United States with and without
access to fixed broadband of 3 Mbps download and 768 kbps upload. The
FCC is now up to the Fourteenth Broadband Progress Report, published for the second
half of 2020, where it states, "As of the end of 2019, the vast majority of Americans,
94% had access to both 25/3 Mbps fixed broadband service and mobile broadband service
with a median speed of 10/3 Mbps. Also as of the end of 2019, mobile providers now
provide access to 5G capability to approximately 60% of Americans..."
 Withwave's
T-Probe is coaxial probe that offers one signal pin on center and several fixed
pitch ground contact with low inductance. This probe provides excellent electrical performance
for applications having test point with adjacent grounds. They have various pitch ranges
of 0.8, 1.5, 2.5 mm from signal to ground contacts and are produced by precision
manufacturing process. The
T-probe
is available for signal probing test in these applications such as RF module signal insertion/output
measurement , high speed digital & high frequency circuit board analysis...
 As mentioned a while back, in the 1980s
while working at Westinghouse Oceanic Davison in Annapolis, Maryland, an engineer
who worked for knew I had recently obtained a 1941 Crosley Model 03CB console style
radio. He generously gave me his
B&K Dyna-Quik Model 650 Vacuum Tube Tester which, although formerly a very
active Amateur radio operator (since boyhood), he didn't need it anymore. The Model
650 is a very comprehensive portable tester used at one time by many professional
radio and television servicemen. My tester also had the Model 510 Accessory Socket
Panel that added an ability to test 50% more tube types. An indication that it is
one of the later model tube testers is the inclusion of a transistor testing socket.
Unlike testing vacuum tubes, all of which plugged into sockets to make them easily
replaceable, testing a transistor or solid state diode required unsoldering or clipping
the device out of the circuit and then soldering back in either the verified still
good device or a replacement. It was one of the reasons electronics servicing people
eschewed the adoption of semiconductors. That, and a lot of money was made by the
sales of replacement tubes, with a typical profit of a dollar or so per tube. The
$169.95 price in 1957 is the equivalent of about $1,720 in 2022... |
