|
 Dealing with the problem of
lightning strikes was of concern long before electronic equipment needed to
be protected from its effects. Fires that were the result of lightning have always
been a problem in nature, but they were really catastrophic to civilization once
cities crowded with close-quartered wooden buildings became the norm. Benjamin Franklin
observed that when the many lightning-induced fires of Philadelphia were sparked
(pun intended), it was almost always the tallest structures in the area that were
hit. Those fire often spread to neighboring buildings and burned down entire city
blocks. It was a devastating and frequency...
 "By observing
spintronic magnetic tunnel junctions in real-time, researchers found these devices
fail at unexpectedly low temperatures, offering valuable insights for improving
future electronic designs. Next-Generation Electronics Degradation A new study led
by researchers at the University of Minnesota Twin Cities is providing new insights
into how next-generation electronics, including memory components in computers,
breakdown or degrade over time. Understanding the reasons for degradation could
help improve efficiency of data storage solutions. The research is published in
ACS Nano, a peer-reviewed scientific journal and is featured on the cover..."
 Arthur C. Clarke's writings and contributions
to science are vast and influential, intertwining his imaginative narratives with
profound scientific concepts. Clarke is credited with proposing the idea of
geostationary
satellites in a paper he published in the October 1945 issue of Wireless World
magazine. Titled "Extra-Terrestrial Relays: Can Rocket Stations Give Worldwide Radio
Coverage?," he described the concept of using a network of geostationary satellites
to provide global radio coverage. Geostationary satellites are satellites that orbit
the Earth at the same rate as the Earth rotates, so they appear to stay in the same
place in the sky relative to a fixed point on the Earth's surface. This makes them
ideal for telecommunications and broadcasting, as they can provide constant coverage
of a particular area without the need for multiple satellites or complicated ground
infrastructure...
 Here we go with three new "What's
Your EQ?" challenges from the July 1961 issue of Radio-Electronics
magazine. Readers submit the problems, which typically involve creating a circuit
to perform a specified function, or determining how a given circuit works. The first
of these is more of a puzzle, since the author shows you how to go about arriving
at the answer. Since incandescent light bulbs are not overly familiar to a lot of
people these days, it might be to the advantage of pre-Millennials who grew up using
them and are acquainted with their properties. The second is an old-fashioned Black
Box challenge that some readers will solve without much...
 "Japanese operator SoftBank announced that
the Sunglaider, its large-scale solar-powered uncrewed aircraft system (UAS) designed
for
High Altitude Platform Station (HAPS) stratospheric telecommunications, was
utilized in a field trial conducted by AeroVironment and the U.S. DoD in New Mexico,
the U.S. During the trial, carried out in early August, Sunglider succeeded in achieving
stratospheric flight, the Japanese operator said. With a wingspan of 78 meters and
the capability to carry payloads weighing up to 75kg, the Sunglider is larger than
other publicly announced HAPS UAS..."
 Monday (any day, for that matter) is a good
day for Carl and Jerry stories, Mac's Electronics Service Shop sagas, Hobnobbing
with Harbaugh, electronics-themed comics, electronics quizzes, and other forms of
nerd entertainment. Here is another of Robert P. Balin's great challenges titled,
"Diagram
Quiz," this one from a 1966 issue of Popular Electronics magazine.
Most RF Cafe visitors will easily identify eight or nine of the ten diagrams. Relatively
few will be familiar with the Rieke diagram (hint: power amplifier designers will
know about it). The Biasing diagram is a bit misnamed IMHO, and could cause confusion...
 Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. Three new ceramic bandpass filters have
been announced for October 2024 - a 2275 MHz center frequency filter with a
bandwidth of 250 MHz, a 2275 MHz center frequency filter with a bandwidth
of 250 MHz, and a 6245 MHz center frequency filter with a bandwidth of
360 MHz. Custom RF power filter and directional couplers designs can be designed
and produced with required connector types when a standard cannot be found, or the
requirements are such that a custom approach is necessary.
 When you read this 1963 Electronics
World magazine article's title, I doubt you immediately assumed it would be
about a vacuum tube circuit, or even one that uses discrete transistors to implement
the circuit. Rather you most likely though it would be about an integrated circuit
(IC).
Operational amplifiers (opamp) are building blocks characterized (ideally) by
their infinite input impedance, zero output impedance, infinite open-loop bandwidth
and gain, zero input offset voltage, amongst other defined parameters. The first
commercially produced integrated circuit (IC) opamp came to market in 1964 via Fairchild
Semiconductor (the µA702, brainchild of Bob Widlar)...
 Nickel-cadmium (NiCad) batteries have a
long and significant history in energy storage, with their invention attributed
to Swedish engineer Waldemar Jungner in 1899. Jungner's work laid the foundation
for an electrochemical power source based on nickel oxide hydroxide and cadmium,
leading to the development of the rechargeable NiCad battery. It was a pioneering
breakthrough because it represented one of the earliest forms of rechargeable energy
storage systems. This battery technology found widespread use in various industries
due to its robust performance and ability to be recharged multiple times. At its
core, the chemistry of NiCad batteries involves the reaction between cadmium (the
negative electrode) and nickel oxide hydroxide (the positive electrode), with potassium
hydroxide as the electrolyte. During...
 These two
tech-themed comics from the September 1969 issue of Electronics World
magazine are pretty good. I especially like the one where the guy's wife entered
his printed circuit board layout in an art contest. PCBs were just starting to gain
momentum in production electronics as they replaced the old point-to-point wiring
method. Also popular in that era was high fidelity stereo equipment. Owning a system
with speakers that operated from 1 Hz through 30 to 40 kHz was major evidence
of an audiophile's technical savvy, even though the human ear con only detect frequencies
in the 30 Hz to 20 kHz range. Dogs can hear frequencies up into the 45 kHz
range. Porpoises can hear up to 150 kHz. A ferret can hear from 16 Hz...
 TotalTemp Technologies offers advanced
and innovative methods for meeting and optimizing your thermal testing requirements.
We specialize in benchtop thermal testing because small batches are typically the
most cost-effective approach. We offer heat transfer by conduction with thermal
platforms, forced convection as in traditional temperature chambers, combined systems,
and thermal vacuum for Space Simulation.
Thermal testing of Traveling Wave Tube Amplifiers and other devices with dramatically
uneven power dissipation can easily be achieved with a dual zone thermal platform.
Managing the heat produced by the electron gun side allows for the RF outputs side
to be tested at various required temperatures. The Dual Zone Thermal Platforms allows
the user to maintain safe controlling...
• Ham
Radio Serving Southeast U.S. Recovery Efforts
• Radio
"A Godsend for So Many" in Helene's Aftermath
• Estate
Planning for Hams
• Intel's Woes Damaging
U.S. Chip Indpendence
• Is
Gen-Z Low Car Ownership a Threat to Radio? (they
can't afford cars due to massive inflation - not because they don't want a car)
 Amrad, American Radio & Research Corporation,
was based in Medford Hillside, Massachusetts and was founded in 1915 with funds
from J. Pierpont Morgan. The company's first manager, Harold James Power, was an
amateur radio enthusiast and built a research laboratory. In 1916, Amrad made its
first broadcast to J. Pierpont Morgan Jr., who was aboard the ocean liner "Philadelphia."
Amrad received orders for military radio equipment during World War I, but discontinued
these orders after the war ended. To keep the company afloat, Amrad produced items
such as electric egg beaters and cigar lighters. In 1919, Amrad was awarded a contract
to make 400 SE1420 receivers, and it began advertising components for amateur radio
enthusiasts...
 This "Which
Dry Battery for You" article is a follow-on from the previous month's "Dry Cell
Battery Types" in Radio-Electronics magazine. It was a time long before the dominance
of rechargeable lithium batteries. In 1963, battery-powered devices were nowhere
near as widespread and diverse as they are nowadays. Hand tools like drills, saws,
routers, planers, and screwdrivers got their power either from a wall outlet or
the user's arm and hand muscles. Lawn mowers, grass and hedge trimmers, chain saws,
and snow blowers were powered mostly by gasoline, although some models plugged into
the wall. Those devices which did use batteries most often had no built-in...
 "Researchers have developed a new architecture
for optical computing called
diffraction casting, offering power-efficient processing by using light waves.
This method promises better integration and flexibility for high-performance computing
tasks and could be used in fields like AI and machine learning. As artificial intelligence
and other complex applications demand ever more powerful and energy-intensive computers,
optical computing emerges as a promising solution to enhance speed and power efficiency.
However, its practical application has faced numerous challenges..."
 The Atomic Energy Commission (AEC) was established
in 1946 as a result of the Atomic Energy Act, signed into law by President Harry
S. Truman. This legislative decision marked the United States' formal entry into
managing and controlling atomic energy, a rapidly advancing field that had been
essential in concluding World War II through the development and use of nuclear
weapons. The AEC was conceived to handle not only military applications of atomic
energy but also to develop peaceful uses, such as energy production, medical research,
and industrial applications. The creation of the AEC emerged from the Manhattan
Project, the secret wartime effort to develop atomic bombs. The Manhattan Project
brought together prominent scientists like J. Robert Oppenheimer, Enrico Fermi,
and Niels Bohr. After the war, however, the question arose...
 Empower RF Systems, the technology leading
provider of high-performance RF amplifiers, is proud to announce the launch of the
Model 2221 X-Band Pulsed High Power Amplifier. The Empower RF 2221 amplifier
operates in the 9-10 GHz X-band, delivering an impressive 8000 W peak
output power with long and short pulse widths. Its applications encompass radar
systems, electronic warfare, HPM research, and electromagnetics effects testing.
With a rugged, modular design, the 2221 offers a reliable, high-performance solution
for applications demanding significant X-band power. Key Features and Specifications
The model 2221 amplifier operates in the 9-10 GHz X-band frequency range, delivering
an impressive 8 kW of peak pulsed output power...
 Although not in the title as it used to
be, this 1964 Electronics World magazine piece by John T. Frye is
a "Mac's
Service Shop" story. If Mac and Barney are the stars of the saga, then it can
be none other. The story is about how the misdeeds of a few dishonest operators
can taint the reputation of an entire industry - nothing new there. Barney is telling
Mac about a "sting" ploy pulled by a consumer protection group whereby TV sets with
a specific easy-to-troubleshoot problem introduced to see how repair technicians
from a suspect company would bill the service. I'll not spoil the ending for you;
however, a comment mentioned that $10 would have been a reasonable price for a house
call that included the fix. According to the BLS's inflation calculator, $10 in
1964 was the equivalent of about $102 in 2024...
 Ever the futurist, in 1962 Radio-Electronics
magazine editor Hugo Gernsback was making the case for occupying
millimeter- and submillimeter-wave bands. In fact, he first proposed the concept
back in 1959. He refers to it as "gap between the infrared (IR) and radio regions."
IR is generally understood to include wavelengths from around 750 nm (400 THz)
to 1 mm (300 GHz). Gernsback cites work done by Professor Gwyn O. Jones,
of Queen Mary College of the University of London, with the claim that among other
advantages of millimeter-wave (mm-wave) is an ability to penetrate certain wavelength
"windows" in the atmosphere where lower frequencies do not propagate efficiently,
more "channels" of communications can be accommodated, smaller antennas could be
used, and narrower focused transmission beams possible...
 Werbel Microwave's WMRD10-7.2-S is a
10-way resistive splitter that covers up to 7.2 GHz with ultra-wide bandwidth.
This unique design accomplishes extremely flat frequency response in a small radial
package. Our unique design approach provides higher than expected isolation between
outputs at far ports than would be achieved in a typical star topology. It has applications
in markets such as CATV, test and measurement, and military radio. Its small size
makes it easy to integrate into compact systems. Designed, assembled, and tested
in the USA.
 Hugo Gernsback, often heralded as the "Father
of Science Fiction," was an extraordinary figure whose influence extended beyond
the realm of speculative literature into the world of electronics, radio communication,
and futurism. His life, inventions, and publications shaped not only popular science
but also the practical development of radio and electronics, making him a pivotal
figure in early 20th-century technological advancements. Gernsback was born Hugo
Gernsbacher on August 16, 1884, in Luxembourg City, Luxembourg, to a wealthy family.
His father, Moritz Gernsbacher, was a winemaker and merchant, while his mother,
Bertha, came from a prominent local family. Hugo had several siblings, though details
of his early family life remain somewhat obscure. From a young age, Hugo showed
a strong interest in science and technology, particularly in electricity and wireless
communication. He attended local schools in Luxembourg and later pursued formal
education at the Technikum in Bingen, Germany...
 These government programs take forever to
implement, then a major portion of the money gets wasted in bureaucracies, payoffs,
and misappropriations (e.g.,
8 EV charging stations after spending $7.5B). "If you know CostQuest at all
you probably think of it as the company that the FCC hired to clean up and refine
its national broadband map. But the company is also working with state broadband
offices on their
Broadband Equity, Access and Deployment (BEAD) programs. To give a little background,
CostQuest works with the FCC on its national broadband map. But it was also hired,
separately, by the National Telecommunications and Information Administration (NTIA)
to work with states..."
 The
Radio Corporation of America (RCA) holds a significant place in the history
of American technology and business. Founded in 1919, RCA was initially created
as a government-sanctioned monopoly to manage the United States' growing interest
in wireless communication. During its peak, RCA was a dominant player across multiple
industries, including consumer electronics, communications, broadcasting, and defense
technology. Its influence extended through radio, television, radar, semiconductors,
and beyond. The inception of RCA was rooted in the growing importance of wireless
communication during and after World War I. The company was established by General
Electric (GE), which was pressured by the U.S. government to create a new entity
that would ensure...
 When this was originally posted it was the
beginning of the IEEE's 2007
Microwave Theory and Techniques Society's (MTT-S) International Microwave Symposium
(IMS) in Honolulu, Hawaii. This advertisement from the January 1969 issue of Electronics
World magazine promoted Institute of Electrical and Electronics Engineers (IEEE)
annual symposium. Per the MTT.org website, the very first IMS show was held in 1995,
in Orlando, Florida. The 1969 IEEE International Convention & Exhibition, which
was not specifically a microwave electronics theme, was held in the New York Coliseum,
located in New York City...
 If you have been wanting access to
nitrous oxide (N2O), aka laughing gas, in order to "encourage" someone
to divulge subconscious (or intentionally suppressed) information, but don't want
to pay the high cost of storage bottles and refilling, then here are instructions
in a 1949 issue of Popular Science magazine for brewing some on your own.
Purchase of N2O is legal, and is used, among other things, as an engine supercharger
which is injected into the intake manifold. I had a friend back in the 1970s with
such a system installed on his 1968 Camaro that had a 454 cu. in. big
block in it. It could easily pop the front wheels off the ground. Dentists and doctors
still use it as an anesthetic, food products like whipped cream...
 The evolution of
Crosley
radio products is a fascinating journey through the golden age of radio, a period
marked by significant technological advancements and changing consumer preferences.
Powel Crosley Jr.'s genius lay in his ability to combine affordability with cutting-edge
features, making his radios highly desirable for the average American household.
Crosley Radio Corporation's products evolved rapidly, reflecting the company's commitment
to innovation and its response to market demands. Crosley's radio journey began
in 1921 when he created the Harko, an affordable crystal set that was small and
compact enough to sit on a tabletop. Early radios at the time were relatively...
 It is amazing how some substrate layouts
look exactly like a block diagram of circuit they represent. "With increasing data
rates in mobile communications, the need for more powerful high-frequency electronics
is growing. This is particularly true for satellite-based global communication networks,
which must function reliably and securely in all weather conditions and at any location.
In the ESA Magellan project, researchers at Fraunhofer IAF, together with UMS and
TESAT, are therefore developing novel efficient
GaN transistors and high-power amplifiers for LEO and GEO communication satellites
to provide high..."
 Allen B. DuMont, a pivotal figure in the
early days of television and electronics, was born on January 29, 1901, in Brooklyn,
New York. His contributions to the advancement of television technology, particularly
through his work on cathode-ray tubes, and the founding of the DuMont Television
Network, left a lasting mark on the broadcasting industry. DuMont's early years
were marked by adversity. As a young boy, he contracted polio, which left him bedridden
for several months. Despite the physical limitations imposed by the disease, DuMont's
intellectual curiosity flourished, and he turned to reading and tinkering with electronics
to occupy his time. This early exposure to electrical engineering would shape his
future. DuMont's passion for electronics was evident from an early age. By the time
he was a teenager, he had built his own radio receiver. He attended Rensselaer Polytechnic
Institute (RPI)...
 Ever heard of "sferics?" That's a new word
in my technical lexicon as of right now. Sferics (aka spherics), is a contraction,
derived from "atmospheric" phenomena, specifically referring to the electromagnetic
signals generated by natural events in the atmosphere, such as lightning discharges.
Over time, its use has become specialized in the field of meteorology, physics,
and certain branches of electrical engineering, where it is used to describe specific
types of electromagnetic emissions. It was mentioned in this "News
Briefs" column in a 1961 issue of Radio Electronics magazine. Also
in the news was the decreasing conductivity of the atmosphere due to low sunspot
activity. Ham DX'ers love sunspots since by charging the upper atmosphere, it facilitates
long distance communications. Japanese color TV sets were deemed "impressive." Much
more...
 "Recent advancements in
phonon laser technology, which utilizes sound waves rather than light, show
promising new applications in medical imaging and deep-sea exploration. A novel
technique enhances these lasers by stabilizing and strengthening the sound waves,
allowing for more precise and powerful outputs. This development not only improves
existing uses in medical and underwater applications but also extends potential
uses to material science and quantum computing. Scientists in China have made a
significant leap in developing lasers that use sound waves instead of light. These
'phonon lasers' hold promise for advancements in medical..."
 Powel Crosley Jr., an American inventor,
entrepreneur, and industrialist, was born on September 18, 1886, in Cincinnati,
Ohio. He became one of the most prolific figures in American industry, with contributions
spanning from radios to cars, and from kitchen appliances to television broadcasting.
His innovative spirit, coupled with a keen business sense, enabled him to leave
an indelible mark on American consumer culture during the first half of the 20th
century. Crosley's early years were shaped by a supportive, middle-class family.
His father, Powel Crosley Sr., was a successful attorney, which afforded young Powel
and his siblings a comfortable upbringing. Crosley was drawn to mechanical and electrical
engineering from an early age, demonstrating an innate talent for tinkering. As
a boy, he built his own working model of a car...
 "In these modern times, electronic systems
are usually operating within an
electromagnetic-interference (EMI) environment that contains many other electronic
systems. These systems need to exist and fully operate undisturbed while meeting
electromagnetic compatibility (EMC). EMC requirements are separated into two main
parts: Electromagnetic immunity - a system must not be disturbed by any other systems.
The electromagnetic interference in a system can't disturb any other system. Then,
if immunity and emission requirements are individually met, the electronic product,
such as an integrated circuit (IC), may be marketed from an EMC point of view. Measurement
methods for EMI and electromagnetic emission (EME) are fully described for ICs in
the IEC62132-4 (immunity) and IEC61967-4 (emission)..."
 The
Space Race was one of the most significant geopolitical and scientific competitions
of the 20th century, driven by the rivalry between the United States and the Soviet
Union during the Cold War. It spanned from the late 1940s through the 1970s, with
a focus on achieving superiority in space exploration, a domain viewed as critical
not only for scientific advancement but also for military and strategic dominance.
Rooted in rocket technology developed during World War II, the Space Race transformed
the world's understanding of science and technology, culminating in the most dramatic
achievement: the landing of humans on the Moon in 1969. This treatise explores the
key milestones, the countries and key players involved, technological developments,
the interplay between military...
|
 For some reason the "too clever by half"
saying (but not in an insulting way) comes to mind when reading this article about
color TV from a 1951 issue of Radio & Television News magazine. The
color television industry was still searching for an acceptable standard broadcast
format when this was written, and the electromechanical contraption was not considered
too elaborate considering the original color TV schemes were all a conglomeration
of whirling colored wheels, light sources, and photodetectors coupled with accommodating
timing and intensity signals. Because there was not agreement on what the final
commercial broadcast signal format would look like, there was not a lot of motivation
for test equipment makers to invest time and money into providing gear for research
and development laboratories. Do you remember the ads for the screen that installed
on the front of a TV set to convert black and white (B&W) to color...
 Mrs. Helen McKee knew exactly what she was
signing up for when she agreed to marry Mr. McKee. After all, she met and got familiar
with the guy over the air during some rag chewing sessions. This story is a humorous
(and true) account of what life can be like for the
spouses of enthusiastic Ham radio operators. We all hope for
such an understanding 'significant other.' Melanie has certainly endured and
supported a lot of my pastime endeavors over the past 32 years. It's a short
read, so take a break and put a smile on your face...
 RCA's Numitron was their answer to the Nixie
tube (manufactured by Burroughs Corporation). It was a simpler 7-segment incandescent
display (DR2010) that, with all lines energized, formed the number 8. It worked
off of +3.5 to +5 volts, with each element requiring 24 mA of current. The
number 8 drew 192 mA of current and dissipated 0.672 W at 3.5 volts and
a whopping 0.96 W at 5 volts! RCA marketed a BCD*-to-7-segment display driver
(the CD2501E). The
Numitron was pitched as a sensible alternative to the 7-segment
LED display, but with an element size of 0.35" wide by 0.6" high, there was no real
advantage over the LEDs, which were just entering the electronics market in 1970.
Numitrons do have a certain nostalgic 'cool' factor, though. It is interesting to
note that the author's last name, Wood, is the same as that of Frank Wood, who was
issued...
 With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils
available for RF, analog, and digital system and schematic drawings! Every stencil
symbol has been built to fit proportionally on the included A-, B-, and C-size drawing
page templates (or use your own page if preferred). Components are provided for
system block diagrams, conceptual drawings, schematics, test equipment, racks, and
more. Page templates are provided with a preset scale (changeable) for a good presentation
that can incorporate all provided symbols...
 All types of
sales and repair services get accused of ineptness of skill which requires more
time than necessary, overcharging for parts and/or labor, underhandedness in faking
problems and selling unnecessary replacement parts, improper customer interfacing,
sloppiness in appearance and/or work environment, failure to arrive on time for
appointments, etc. Some of the most often cited these days are auto mechanics, cellphone
repairers, home improvement contractors, lawn care, and builders. Up until about
a decade ago when cellphone repair began to dominate over computer repair, the latter
was a big source of complaints. In the 1950s and 60s, it was TV and radio repairmen
who took a lot of abuse not just from their customers, but from large, organized
electronic service conglomerates and were abetted by mostly ignorant media outlets
looking for a good story ...
 In spite of the proliferation of cellphones
and near ubiquitous communications, there are still many applications that require
private
2-way communications systems. Emergency services like police,
fire, and ambulance; amateur radio, vehicular dispatch for utilities, delivery and
repair services; and anywhere that cellular service is not either available or extremely
reliable, cannot rely on cellphones for mission critical needs. There are a lot
of legacy 2-way radio system antennas and associated towers still being used and
many new installations in place. Word has it that use of Citizen Band (CB) radio
is on the rise amongst not just truck drivers but everyday drivers and base station
operators - largely for the anonymity factor...
 Hugo Gernsback is not necessarily a household
name in 2020, but in the early to middle 20th century, he was fairly well known
in both the hard science and science fiction realms. He was a prolific author of
books and magazines in both areas, applying his profound knowledge of technology
and his ability to foretell the futures of many aspects of communications, mechanics,
electronics, and marketing and societal behavior to the aforementioned. If you are
a regular RF Cafe visitor, you have seen very many articles written by Hugo Gernsback
reproduced. This particular work of prognostication appeared in a 1947 issue of
his Radio-Craft magazine. It presciently claimed that a post-war boom in
consumer buying after half a decade of sacrifice of creature comforts for the good
of the country and world would feed a significant adoption of
FM radio
over...
 Rudolf Engelbrecht, an alum of Oregon state
University, was inducted into the institution's Engineering Hall of Fame in 1998.
As evidenced in this full-page advertisement in a 1958 issue of Radio &
TV News magazine, Mr. Engelbrecht's work was instrumental in advancing
the state of the art in communications electronics while an engineer at Bell Labs.
Here, he is show with the four-stage
junction diode amplifier developed for military applications. It exploited the
variable capacitance nature of a varactor type diode to effect amplification in
the UHF and microwave bands. Engelbrecht went on to work at Radio Corporation of
America (RCA) later in his career. BTW, if you are wondering what other kind of
diode might there be other than a "junction" diode ...
RF Cascade Workbook is the next phase in the evolution of RF Cafe's long-running
series, RF Cascade Workbook. Chances are you have never used a spreadsheet
quite like this (click
here for screen capture). It is a full-featured RF system cascade parameter
and frequency planner that includes filters and mixers for a mere $45. Built in
MS Excel, using RF Cascade Workbook is a cinch and the format
is entirely customizable. It is significantly easier and faster than using a multi-thousand
dollar simulator when a high level system analysis is all that is needed...
 This
Physics & Science Theme crossword puzzle for August 1st, 2021, contains
only words and clues related to engineering, mathematics, chemistry, physics, and
other technical words. As always, this crossword contains no names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort unless
it/he/she is related to this puzzle's technology theme (e.g., Hedy Lamarr or the
Bikini Atoll). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!
 Ed Troy, owner of Aerospace Consulting, was
kind enough to offer a few of his articles for posting on RF Cafe. With more than
30 years in the electronics communications design field, Ed has a lot of valuable
knowledge to impart to us mortals ;-) This third paper demonstrates why using a
highly capable software simulator for system design work is essential because of
its ability to predict and facilitate mitigation of system-generated problems prior
to building and testing the prototype. Case in point are
spurious spectral components generated by the local oscillator and SSB to PM
conversion created in a frequency doubler circuit. This paper was adapted from an
example circuit provided in Keysight (formerly Agilent) Genesys Spectrasys. Spectrasys
is a spectral domain block diagram simulator that allows the user to construct a
system model and quickly determine the system performance. Whether you are involved...
 This quiz is based on the information presented
in "Introduction
to Infrared and Electro-Optical Systems," by Ronald G. Driggers and Melvin H.
Friedman. All RF Cafe Quizzes make great fodder for employment interviews for technicians
or engineers - particularly those who are fresh out of school or are relatively
new to the work world. Come to think of it, they would make equally excellent study
material for the same persons who are going to be interviewed for a job.
 By 1957,
betatrons, cyclotrons, cosmotrons, synchrocyclotron, bevatrons, and other forms
of "trons" had the physics world all agog with anticipation of the next big discovery.
Quarks were still a decade away from being discovered and something as exotic as
the Higgs boson (aka god particle) hadn't entered anyone's mind. The news media
was agog with reports of the world possibly coming to the end as a result of those
experiments sparking a nuclear reaction chain that would cause the whole world to
explode. Today, the news media is no smarter, because nowadays they fret over the
Large Hadron Collider (LHC) generating a black hole that will implode the whole
world ...
 Raise your hand if you're old enough to remember
doing printed circuit board layout using
Rubylith tape. My hand is up. Back in the early 1980s, I did prototype
PCB designs in an engineering development lab at Westinghouse Electric's Oceanic
Division. Most of it was for analog and RF substrates that would be photographically
reduced in size for use with bare integrated circuit die and surface mount passive
components (Rs, Ls, and Cs), upon which I would later epoxy-mount those components
and wire-bond everything using 1-mil gold wire. However, there were projects where
full-size leaded components were used on a through-hole PCB that used not only the
Rubylith tapes but also sheets with special electronics shapes for solder pads
around the holes for components leads, ground and power planes, board-edge
connectors...
 This installment of the multi-month series
of articles on antenna principles covers
directional arrays for 300 MHz and higher. Keep in mind that in 1947 when
this appeared in Radio-Craft magazine, wavelengths of a meter or less were
considered to be at the upper end of the operational range. Parabolic reflector
antennas were the domain primarily of ground-based installations due to the physical
size and weight being prohibitive in airborne platforms, and even then they were
rarely used at the time. Most ground and airborne installations were composed of
dipole antennas with various configurations of reflector and director elements for
desired gain and directivity characteristics. Special applications like for direction
finding and longer wavelength radio communications used loop and long wire antennas,
respectively. Highly directive dipole...
 Listen to the
RF Cafe Podcast. At the time this Mac's Service Shop episode appeared in
a 1957 issue of Radio & TV News magazine, electronics technicians were
beginning to see a lot of
transistorized radios, televisions, record players, and tape recorders showing
up in place of the very familiar vacuum tube models. It was a whole new ballgame.
To complicate matters, biasing, interstage coupling, and tuning circuits were in
many ways different requiring re-learning what a "typical" circuit looked like,
and the introduction of printed circuit boards in place of point-to-point wiring
made changing components more difficult. Delaminating metal traces was easy to do
on early PCBs when using the big, high thermal inertia soldering irons required
for larger and more heat-tolerant components. Author John T. Frye used these
Mac's Service Shop stories...
 You always need to pay careful attention
to "breakthrough" type articles when they appear in April issues, since many magazines
have a tradition of burying an "April Fools' Day" item without notice. This April
1932 issue of QST magazine seems to be legitimate. The term "lycopodium
pattern" aroused my suspicion, but it turns out to refer to a pattern of vibration
that resembles the needle orientation of certain pines and cedars. As radio frequencies
continued to increase during the early years of "wireless" development, the use
of quartz crystals as a stable reference source ran into a physical limitation because
as crystal slices reached a certain thinness, overtone and subharmonics appeared
that caused problems in circuits. A new mineral called tourmaline saved the day.
With an elasticity much greater than quartz, tourmaline is able to vibrate at higher
fundamental frequencies for a given thickness...
 Waveform shaping is essential in today's
crowded communications spectrum. Spectral masks are precisely defined in order to
prevent "spreading" beyond the allocated frequency ranges at defined power levels.
Whenever anything other than a continuous sinewave is being broadcast, there is
spectral content generated in addition to the fundamental frequency. A Fourier transform
of the waveform reveals which frequencies at what power levels comprise the waveform.
The CW signal used by Morse code operators is a pure sinewave (or nearly so), but
there is a spectral problem with it every time the signal turns on or off because
of the square-ish edges involved during switching. RC networks are used in the transmitter
circuits to tame the edges so that they do not turn on and off so quickly and in
doing so reduce the extraneous frequency content. Author George Grammer argues that
even though the signal could theoretically be made "clickless" (aka "chirpless"),
there is an auditory benefit to the clicks or chirps that aids operators listening
to high speed code transmissions...
 RF, IF and baseband amplifiers; RF, IF, and
baseband filters; fixed and tunable local oscillators, single- and double-balanced
mixers, attenuators, envelope detectors and phase detectors, directional couplers,
power combiners and dividers, et cetera, are all component types used for
receiver systems regardless of whether vacuum tubes or transistors
comprise the active parts. In 1972 when this article appeared in Popular Electronics
magazine, people were beginning to get comfortable with the idea of transistorized
products replacing the familiar tube. Instant-on televisions and radios were...
 Now here is a profound ode to one of the
most noble of technician genres ever to tweak a receiver front end or to change
out a transmitter magnetron -
The Radar Man!! It appeared in a 1960 issue of Popular Electronics magazine.
Some of you know that I worked on airport surveillance and precision approach radar
in the USAF, so my bias is established. Hmmm... now that I read the poem more carefully,
I realize that it is not complimentary at all. It must have been one of those jealous
TACAN or satellite communications technicians that wrote it!
 With a cover date of August 25, 1945, this
issue of The Saturday Evening Post obviously went to print some time prior
to the dropping of the two nuclear bombs on Japan that ended World War II. Victory
in Japan Day (V-J Day), was August 14, 1945. There is no hint inside the magazine
that the end of the war was nigh. There were, however, plenty of ads by companies
touting their contributions to the war, and even some ads, particularly food ads,
anticipating the end of rationing. Within this edition is also a short quiz entitled,
"How's Your Radio Knowledge?" The author, Captain James F. C.
Hyde, Jr., challenges readers to identify the locations of radio stations just
by looking at their call signs. As is done today, most stations attempt to get
call signs that are relevant to their location...
 Magnetic amplifiers (aka "mag amps") use
a property of saturated core inductors (saturable reactors) to obtain signal amplification
via a transformer-type plus diode-assisted voltage multiplication.
Magnetic amplifiers were preferred over vacuum tube amplifiers in some circuits
because they do not require a high bias voltage, are generally smaller in size,
are quite robust and are practically immune to microphonics. Their biggest limitation
is bandwidth. The high number of turns in the core provides a lot of interwinding
capacitance so the self-resonant frequency is in the low megahertz range. Additionally,
the need for the magnetic amplifier reactor to operate in a saturated condition
further imposed a limit on the frequency response. Even today, there are some critical
applications that exploit the fool-proof and ultra high reliability nature of the
magnetic amplifier. This article goes into the details of operation both as amplifiers
and as bistable multivibrators...
 It should come as no surprise that in the
pre-safety-ground era which included the 1960s that electrical shocks of patients
in hospitals was not uncommon. If the jolt came intentionally from a cardiac defibrillator,
then it would be a good thing. However, these shocks, which were the subject of a
Time magazine story in the April 18th, 1969 issue cited by Mac's technician, Barney,
were being administered unintentionally by patient monitoring and ancillary life-sustaining
equipment. Per the article, no Underwriter's Laboratory (UL) certification was required
for hospital equipment. Maybe it was felt that it wouldn't be so bad if someone got zapped
in the hospital since there would be a doctor on-hand to resuscitate the zapee. Since
that time medical equipment has been required to undergo stringent safety conformance
requirements that makes electrocution virtually impossible. Now, if we could just keep
doctors from cutting off the wrong limb or removing the wrong organ...
 Hmmm... this is the first time recall either
of Carl's or Jerry's father, at least where either was present in the story. Their
mothers are mentioned on occasion for providing sandwiches or uttering words of
caution when embarking on a sleuthing mission. In this episode entitled "Two Tough Customers," creator and author John T. Frye have
the techno-teens set out on an adventure to shop for a good deal on a fundamentally
sound car - which they would own in a partnership set up by their fathers. As you
would expect if you are an ardent C&J follower, their effort includes inspecting
not just the mechanical integrity but also the electrical system health. Frye always
used his stories as the basis for a lesson on some technical aspect of everyday
life. The boys broke teenage car owners into three groups: Hot-Rodders, Show-Offs,
and Mechs. They seemed to assign one trait or the other, but not a combination
thereof. Personally, I was a bit of all three with my first car - a 1969
Camaro SS. While reading, see if you notice what I did about the battery
measurement...
 The term "modern" in the title of any book
or article never has set right with me because it is utterly ambiguous about the
era to which "modern" refers. Sure, it sounds good at the time, but when applied
to this 1966 QST article, "modern" should be replaced with "four-decade-old."
However, in this case the content is still relevant even thought it was written
so long ago (or else I would not be reproducing it here). It may well have been
most people's first exposure to
elliptical (Cauer) filters. As you might expect, the rigorous, headache-inducing
mathematics is omitted, but the article does give an example of implementing an
audio frequency bandpass filter by cascading a lowpass filter and a highpass filter.
If you are familiar with filter design, you know that because of phasing and inband
impedance mismatch issues you cannot simply butt the two together to yield an equivalent
bandpass filter. In fact, the author found it necessary to insert a 13 dB attenuator
between them in order to get acceptable performance...
 It was a lot of work, but I finally finished
a version of the "RF &
Electronics Schematic & Block Diagram Symbols"" that works well with Microsoft
Office™ programs Word™, Excel™, and Power Point™. This is an equivalent of the extensive
set of amplifier, mixer, filter, switch, connector, waveguide, digital, analog,
antenna, and other commonly used symbols for system block diagrams and schematics
created for Visio™. Each of the 1,000+ symbols was exported individually from Visio
in the EMF file format, then imported into Word on a Drawing Canvas. The EMF format
allows an image to be scaled up or down without becoming pixelated, so all the shapes
can be resized in a document and still look good. The imported symbols can also
be UnGrouped into their original constituent parts for editing...
 Most of us are likely familiar with the ongoing
debate over whether
radiation from cellphones, Wi-Fi routers and laptop computers, cell towers,
smart meters, and other such modern gadgetry is harmful to humans. It is not
ionizing radiation like nuclear decay, but there are heating effects that can
cause damage under the right conditions. One week news breaks from the latest
organization shocking the public with proof of tissue cell damage to brain,
hand, face, eyeball, and groin tissue (from laptops). The next week brings a
counter report refuting apocalyptic claims of previous studies... then the cycle
repeats. Early in the age of ubiquitous wireless devices, those seeking to
mitigate worries of radiation argued - somewhat correctly - that enough time had
not yet passed to collect statistically meaningful data. If significant harm
could be proven right away, dismissing the empirical results...
 Monostable multivibrator, one-shot multivibrator,
monocycle multivibrator - it's a matter of semantics, although
the circuit designer doesn''t necessarily think so. The distinction, evidently, is
that this monocycle multivibrator uses a positive-going pulse as a trigger and the
output in its rest (stable) state is a digital "0" (low). A mere 2 mA of current
flows since all the unijunction transistors (UJTs) are turned off. A UJT, to refresh
your memory, is not used as a linear amplifier because of its regenerative, negative
resistance operating region that causes it to effectively lock into a fully on or
fully off conduction state until an external stimulus causes...
 September 6th's custom
Antennas
themed crossword puzzle contains only only words from my custom-created lexicon
related to engineering, science, mathematics, chemistry, physics, astronomy, etc.
(1,000s of them). Clues with an asterisk (*) are specifically antenna-related. 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, find someone
or something in the otherwise excluded list directly related to this puzzle's technology
theme, such as Hedy Lamarr or the Bikini Atoll, respectively. The technically inclined
cruciverbalists amongst us will appreciate the effort.
 Lots of
RF transmission cable parameter charts are available on the Internet, but what
sets this one apart is that is has entries for some of the popular 300 Ω
twin-lead cables of the rooftop television antenna era. It appeared in a 1956 issue
of Radio & Television News magazine. Mentioned in the article is the
reason most TV lead-in cable was colored brown was to help keep the sun's ultraviolet
rays from penetrating and deteriorating the plastic. Author Robert Gary claims silver
coloring was also used to reflect the UV, but I don't recall ever seeing silver
twin-lead - maybe it was a regional thing like for in the southwest. At the time,
μμfd (micro-microfarad) was commonly used rather than pF (picofarad). He also mentions
the G-Line transmission cable used by many of the... |
