See Page 1 |
2 | of the January 2026
homepage archives. Thursday the 15th
 Johanson Dielectrics and
Johanson Technology, located in
Camarillo, CA, are now supporting RF Cafe's publication. Johanson Technology designs
and manufactures RF & microwave ceramic chip capacitors, inductors and integrated
passives. These includes chip-format antennas, capacitors, lowpass, highpass, and
bandpass filters, couplers, inductors, baluns, power dividers, substrates, chipsets.
 Johanson Dielectrics has produced ceramic
chip capacitors for over 60 years. They design and manufacture capacitors that include
standard and high-voltage SMT ceramic chip capacitors, as well as a variety of standard
and custom high voltage & high capacitance value ceramic capacitors.
Please return the favor by exploring their offerings when planning your projects!
 Allen Kushner's (Times Wire and Cable) 1968
Electronics World magazine article portrays
coaxial cables as essential microwave components with impedance, power-handling,
attenuation, time-delay, and shielding traits that must hold steady over broad frequency,
temperature, and harsh environmental conditions like moisture, corrosion, and flexing.
Optimal use demands impedance matching for maximum energy transfer, minimizing VSWR,
radiation losses, and delays; dielectric selection -- solid polyolefins/PTFE for
moisture resistance versus low-loss foamed or air-spaced types with aluminum sheaths
reducing attenuation by 20%; and superior shielding, from ~80 dB in single-braid...
 I have to admit to not recalling ever having
heard of Dagmar; have you? Crack electronics technician "Red" mentioned her in this
episode of "Mac's Radio Service Shop" appearing in the March 1952 edition
of Radio & TV News. I thought Prince and Cher were the first man (ostensibly)
and woman, respectively, to use a single-name public moniker, but evidently Dagmar
beat them to the punch ...but I digress. John T. Frye, author of the popular
Carl & Jerry series that appeared later in Popular Electronics magazine,
wrote this series before that time. On this cold and wintry day, Red and Mac are
discussing troubleshooting methods and how looking for and interpreting certain
symptoms...
 "Finding accurate positions in dense urban
areas remains difficult for satellite-based navigation systems, where high-rise
buildings and signal blockages can cause large errors or complete loss of service.
A recent study outlines a deeply integrated positioning method that combines commercial
5G New Radio (NR) signals with Global Navigation Satellite Systems (GNSS) to
address these issues. By reinforcing 5G signal tracking and tightly merging it with
satellite measurements, the approach improves both ranging stability and overall
positioning accuracy in demanding city environments..."
 Even with the ready availability of programmable
calculators and smartphone apps, there are still times when having a handy-dandy
nomograph printed out and hanging on the wall for quick reference can be a great
asset. This nomograph which appeared in a 1965 issue of Electronics World
magazine provided ready conversion between two different (input and output) voltage
and power values to equivalent decibel values. It seems strange that the watts and
voltage scale is on the left and the milliwatts and millivolts scale is on the right.
That might be more intuitive for a nomograph of attenuation, but not - at least
to me - for positive gain as through an amplifier...
 Seamless
integration of wireless communications with wired communications
has not always been a yawn in technical strategy discussions. It has really only
been since the early 1990s with the introduction of ubiquitous cellphone systems
that someone on a wireless device could connect directly with a wired contact and
not need an intermediary operator to facilitate. Some military comms, the Inmarsat
system and a few other proprietary systems were available, but not to the public
at large. This article reports on some of the Army's early attempts at implementing
wireless-to-wired communications, specifically as implemented during the Normandy
Invasion on D-Day (June 6, 1944). Unlike present...
 Alliance Test Equipment sells
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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.
Wednesday the 14th
 Proper grounding often makes the difference
between success and failure in a circuit - from DC to light. I recently fix an intermittent
hum in a vintage cassette tape deck by discovering and repairing a cold factory
solder joint on the shield connection of an input RCA plug. Improperly grounded
shields in electronic circuits cause coupling and interference issues, addressed
via single-point or multi-point grounding based on interference frequencies, cable
length, and circuit sensitivity to high- or low-impedance fields. Single-point grounding
suits short shields (L/λ < 0.15, where L is length and λ is wavelength of highest
frequency), with each insulated shield grounded individually, effective for low
frequencies like audio but failing against magnetic...
 "Researchers based in France, USA and Italy
claim the first demonstration of avalanche breakdown behavior in
quasi-vertical gallium nitride (GaN) diodes fabricated from selective area growth
(SAG) material on silicon (Si) substrate. The advantage of avalanche breakdown is
that it is non-destructive. The breakdown of the diodes was 720V at room temperature.
The team, from Université Grenoble Alpes in France, Stanford University in the USA,
and University of Padova in Italy, believes that the performance of the devices
can be improved “through the optimization of the design geometry..."
 Narrow-band frequency modulation (NFM) was
a relatively new technology in 1947, having been advanced significantly during World
War II. Amateur radio operators were just getting their gear back on the air
after having been prohibited from transmitting for the duration of the war. Few
were probably thinking about adopting and exploiting new modulation techniques,
but for those who were and recognized FM as the path to the future of radio, QST
published this fairly comprehensive treatment of both frequency modulation (FM)
and phase modulation (PM). Mathematically, FM is the time...
 The advent of
FET-input multimeters greatly reduced reading accuracy errors
due to not taking into account the impedance of devices being measured. A certain
amount of familiarity with how to interpret the indication on a meter movement on
analog meters is still required based on the multiplier switch position and scale
selected, but for most users simply reading the number beneath the pointer - or
interpolating its position between two numbers - is good enough. Mirrored scales
take the some of guesswork out of that by reducing parallax issues. Finally, digital
multimeters (DMMs) hit the scene and made slackers out of just about all of us when
it comes to making voltage, current, and resistance measurements. With few...
 Withwave manufactures an extensive line
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board edge, panel mount), calibration kits (SOLT), a
fully automated 4-port vector
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.
Tuesday the 13th
 The "Recent
Developments in Electronics" column in a 1968 issue of Electronics World
magazine featured among other topics, a six-foot McDonnell-Douglas DC-10 jet model
tested inside a charged wire enclosure generating controlled electromagnetic fields
to evaluate communications and navigation antennas across flight attitudes on the
179-foot tri-jet led to modern anechoic chambers for 5G and aircraft testing. An
all-solid-state bright radar display provided daylight air traffic control to enhance
monitoring and safety to replace dim scopes. A nuclear reactor attained criticality
with 211 fuel elements for 600 kW thermal power in a 66-lb flight unit convertible
for moon/orbit craft, inspiring RTGs in Voyager and Perseverance rover...
 Not sure what the image has to do with the
subject, but... "Electromagnetic
compatibility (EMC) and compliance engineering are critical fields in ensuring
that electronic devices operate without causing or being affected by electromagnetic
interference (EMI). As technology advances, new challenges and opportunities arise
in EMC and compliance engineering. This article explores emerging technologies,
innovations in EMC testing, and potential future challenges in the field. Emerging
Technologies..."
 It is a pretty good bet that most multi-element
TV aerials you find on rooftops and even on ancient towers were decommissioned years
ago. They have been replaced either with cable (whether via CATV or Internet) or
satellite dishes. A few hold-outs still use them for local over-the-air broadcast
stations and/or even FM radio reception. There was a time, though, that photographs
taken looking across a vast expanse of house roofs showing an endless array of antennas
and guy wires was a sign of 'modern' living. Most were erected by Harry Homeowner
types or minimally qualified service technicians, and were well-known for toppling,
twisting, bending or un-aligning when stiff winds were imposed upon them. This story-lesson
from the March 1953 edition "Mac's Radio Service Shop...
 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. Our
WM2PD-0.45-7.5-S is a 2-way in-line power splitter covering the continuous bandwidth
of 450 MHz to 7.5 GHz in an enclosure measuring 5.75 x 2.80 x 0.55 inches
with versatile mounting options. The device is RoHS compliant. This part has versatile
mounting options. Through holes allow for mounting to chassis on the broad side.
Threaded holes on the connector edges allow for through-panel mounting. No worries
with Werbel...
 A mere five years had 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...
Monday the 12th
 In his 1968 Electronics World magazine
article, Amphenol RF Division VP Tore Anderson emphasizes that
selecting coaxial connectors is as crucial as choosing the cable itself for
optimal RF transmission system performance, maintaining constant impedance despite
dielectric transitions and withstanding power without disrupting VSWR. Engineers
often prioritize familiarity over suitability, leading to problematic adapters and
system degradation, while even manufacturers misuse inexpensive types for high-power
applications, risking damage. Connectors are classified by cable size, coupling
methods (bayonet, threaded, push-on)...
 Arthur Steele is probably enjoying retirement
from
Littelfuse by now. In 1965 he had an article published offering
guidelines on how to select the proper type fuse for protecting the circuit at hand.
The correct choice is seldom a simple matter of adding a margin of some amount onto
the known maximum current draw, especially if you are designing for a commercial
or defense electronics project. Applied voltage, expected current surges, operational
temperature and mechanical stress (vibration & shock, etc.), applicable design
regulations (UL, Mil-Spec, etc.), serviceability, and available space are among
the factors that need consideration. Do you need a fast-blow, medium-blow, or slow-blow
fuse for that circuit? You'll have...
 Anatech Microwave Company (AMC) 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 November, including a 20 dB directional
coupler with an insertion loss of 0.5 dB over a 2-18 GHz range, a 1 dB
attenuator for 1 kW peak pulse at up to 4 GHz, and an 8-way power divider
with 3° phase balance over 0.5-150 MHz. Custom RF power filter and directional couplers
designs can be designed...
 This week's
crossword puzzle has a "directional coupler" theme in that many
of the words are related to the devices. All of the other words are, as usual, pulled
from a custom-built dictionary containing only terms pertaining to engineering,
mechanics, astronomy, mathematics, chemistry, and names of companies that make components
for the aforementioned fields. Even Dilbert characters appear sometimes. You will
not, however, find names of numbnut Hollywierd celebs or TV shows here...
 Longtime RF Cafe visitor Steve M. sent
me a note about his new RFGraph system modeling
software. It is an online cascade calculator with a drag-and-drop user interface.
Standard or custom components can be placed on the drawing grid, and all system
parameters -- gain, NF, IP, P1dB, etc., can be viewed at any point in the chain.
Your design is stored in the cloud and can be easily shared with other users or
exported to PDF for inclusion in presentations and white papers. A Basic account
with limited capability is free, and a full-featured Pro account is a mere $9.99/month
or $99/year. Try it today!
 May 6, 1937, is the date of the
Hindenburg disaster at the Naval Air Station in Lakehurst, New Jersey, and is
the RF Cafe logo theme for that Day in History . While looking through the July
1936 edition of Radio-Craft magazine, I saw this news article reporting
on preparations being made in the onboard radio and direction finding equipment
for Hindenburg's maiden voyage from its home base in Frankfurt, Germany to North
America. No one at the time of this article suspected such a terrible fate was looming
les than a year later. Theories abound regarding the cause of the fatal fire, but
there is no doubt that a combination of highly flammable hydrogen gas and an also
highly flammable graphite dope...
Friday the 9th
 Log-periodic dipole array (LPDA) antennas
have been a favorite of homeowners and hobbyists since they were first invented
back in the late 1950s by Dwight Isbell and Raymond DuHamel at the University of
Illinois. In this 1967 Electronics World magazine article, Harold D. Pruett,
an assistant physics professor at Colorado State University, outlines DIY zig-zag
designs for FM and TV reception, costing under $5 in materials. The FM-only and
VHF TV-FM antennas provide 10-12 dB gain, 5° beamwidths, and over 20 dB
front-to-back ratios, enhancing signal-to-noise by focusing on transmitters and
rejecting noise, multipath distortion, FM stereo hiss, and TV "snow" or ghosts...
 Effective January 19, Innovative Power Products
(IPP), an RF Cafe advertiser, will be relocating our operations from Holbrook, NY
to a
new facility at 90 Davids Drive, Hauppauge, NY 11788. This important step
for IPP will allow us to better support our customers, giving us more capacity in
a newly-renovated manufacturing location. All shipping, receiving, and in-person
visits will transition to the new site. Our team, ownership, and commitment to quality
and service, phone numbers, emails, and primary points of contact all remain the
same!
 James Kilton Clapp in 1948 first published
details on an oscillator that used positive feedback obtained from an LC (capacitive &
inductive) voltage divider to initiate and sustain oscillations. Thus was born the
now familiar Clapp oscillator. It had an advantage over both the Colpitts and Hartley
oscillators because the feedback, not being dependent on a simple capacitive or
inductive voltage division, respectively, made it more reliable as a variable frequency
oscillator (VFO). This article does a nice job of explaining the operation of the
Clapp oscillator. Just as the Colpitts and Hartley oscillators handily provide an
easy mnemonic for being based...
 ARRL
The National Association for Amateur Radio® is launching a year-long celebration
that puts the spotlight squarely where it belongs -- on radio clubs. Beginning January
1, 2026, ARRL officially recognizes the
Year of the Club, an initiative designated by the ARRL Board of Directors to
honor the vital role clubs play in sustaining, growing, and energizing amateur radio.
Radio clubs are the backbone of ARRL and of the Amateur Radio Service itself. For
countless hams, a club is the first welcoming doorway into the hobby -- a place
to learn, to operate...
 Magnetic ceramics have been with us for
a long time - probably forever as far as most people that use them these days are
concerned. When this article was published in 1953, ferrites for use at RF frequencies
were a new, breakthrough phenomenon. Take a look at inductors used in vintage radio
equipment and you will find either air or solid iron as the permeable filler elements
in most instances. Whereas iron might have a permeability of 100-150, the new magnetic
ceramics exhibited permeabilities up to 4,000 at 1 MHz, and even higher for
lower frequencies. Modern alloys and compounds provide permeabilities of more than
50,000 for special applications. Such high values allow physical size and weight
of inductors and transformers...
 When I first saw this article from a 1946
edition of
Radio News, I did a double-take on the author's name, thinking
it was written by long-time model aviation author and magazine editor William "Bill"
Winter. It was actually done by a fellow named Winters, not Winter. An enthusiastic
radio control (R/C) evangelist in his day, Bill Winter wrote many pieces for electronics
magazines such as
Popular Electronics. As I have noted in the past, hobbyists in
the electronics realm, as well as in the fields of aircraft and rocket design, contribute
mightily to the state of the art. Such is also the case in many other arts and sciences.
Here we have a report of some of the earliest radio controlled flying "drones,"
as we call them today. They are a far cry from the...
Thursday the 8th
 This 1967 Electronics World magazine
article detailed the FCC's at-the-time
incentive licensing program that established a strict hierarchy where exclusive
frequency blocks were reserved solely for Advanced and Extra Class operators, creating
clear privileges based on examination proficiency. This system mandated Morse code
testing at 13 wpm for General class and beyond, with the explicit goal of pushing
hams toward technical excellence by restricting prime DX and phone segments. Today's
licensing structure retains a modified version of class-based frequency assignments,
but the distinctions are far less restrictive. While some band segments remain allocated
to specific license classes like Technician, General, and Extra, the partitions
are more permissive and designed for operational convenience rather...
 Just as modern high power semiconductor
amplifiers are composed of cascoded (connected in parallel) lower power amplifier
units, so too a
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.
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. Richardson Electronics
is a major distributor for...
 "'AI is not going to take your job.
The person who uses
AI is going to take your job.' This is an idea that has become a refrain for,
among others, Nvidia CEO Jensen Huang, who has publicly made the prediction several
times since October 2023. Meanwhile, other AI developers and stalwarts say the technology
will eliminate countless entry-level jobs. These predictions have come at the same
time as reports of layoffs at companies including IBM and Amazon, causing anxiety
for tech workers - especially those starting their careers, whose responsibilities
are often more easily automated. Early reports have borne out some of these anxieties
in employment data..."
 Side-looking airborne radar started out using
a narrow beam formed by reflectors, like traditional radars, as opposed to the synthetic
aperture type most often (maybe even exclusively) 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.
Modern computer-controlled synthetic radar beams can be segmented and directed off-axis
for detected areas of interest as required, but the early systems simply gathered
radar return data and presented it real-time, with some level of analog processing,
to operators...
 This is one of a multi-part series of articles
that appeared in Popular Electronics magazine on using an
o-scope to analyze signal waveforms. An introduction to square
waves and how to accurately measure them is covered here. Frequency-compensating
the o-scope probe is always an important step prior to sampling just about any waveform
other than a pure sinewave, because per Fourier series analysis, every periodic
waveform can be defined by a series of sinewave and various frequencies, phases,
and amplitudes. The author demonstrates with a square wave being composed of the
fundamental frequency and its odd harmonics. I remember being amazed to learn whilst
in engineering school that...
Wednesday the 7th
 In this "Mac's Service Shop" article entitled
"Technical
Writing," John Frye presents a critical dialogue on technical journalism, where
Mac contrasts self-aggrandizing writers with true professionals who prioritize substance
over style. The article outlines the essentials of effective technical writing:
originality, clarity, proper organization, and the ability to inspire action, all
while avoiding the insertion of the author's personality between the reader and
the subject. This critique finds a parallel in the automotive journalism of the
1970s, as with figures like "Mechanix Illustrated" magazine's Tom MacCahill...
 Ironically, an RF Cafe visitor just within
the last couple days wrote about possibly getting his Amateur radio license in order
to permit live broadcasting of his
kite-borne video camera system (known as "Kite Aerial Video" [KAV]),
or Kite Aerial Photography [KAP]). Slow scan television SSTV has long been a popular
facet of Ham radio since prior to broadband Internet connections, it was the only
practical method available. Older equipment was large, heavy, power hungry, and
relatively expensive, but today you can buy a much improved camera for a few bucks
that transmits real-time via an unlicensed 2.4 GHz wireless link. That data
stream can be recorded for later use of streamed real-time to the Internet. As with
so many other things, easy availability take some of the challenge out of it, but
the world benefits from...
 "By now, it's no secret that utility companies
are struggling to meet the unprecedented surge on North America's aging power grids,
particularly due to rapidly rising demands for AI-based services from new data centers
popping up across the country. New energy plants, transmission lines, and faltering
coal plants are all leading to increased utility bills for ratepayers. In addition,
the AI boom is creating a second, less well-known crisis: The
data centers' thirst for cooling water strains the water supplies and water-related
infrastructures in many areas. It turns out that data centers' steadily growing
appetite for energy and water..."
 As radio frequencies moved up into the UHF
realm of 30 MHz (through 3 GHz), designers noticed that the old methods
and equations for winding inductors (aka coils and chokes) no longer performed as
predicted. The culprit was
stray capacitance created by the wire itself and the insulation
between windings. To some extent, the length of leads running from the inductor
windings to connection points (terminal strips and lugs at first and then later
printed circuit boards) generated enough extra inductance to add noticeably to total
inductance. New methods were developed to help mitigate the effects of these stray
(aka parasitic) reactances. Much new knowledge in this area was gained through the
war efforts with many radar...
 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...
 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 6th
 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...
Monday the 5th
 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...
Friday the 2nd
 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...
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. Some quoted items have been shortened
to save space. About RF Cafe.
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