|
 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...
 Anatech Electronics (AEI) manufactures and
supplies RF and microwave
filters for military and commercial communication systems, providing standard
LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard
RF filter and cable assembly products are published in our website database for
ease of procurement. Custom RF filters designs are used when a standard cannot be
found, or the requirements dictate a custom approach for your military and commercial
communications needs. Sam Benzacar's monthly newsletters address contemporary wireless
subjects. Please visit Anatech today to see how they can help your project succeed.
 Yay, Friday is here at last! To help you
wind down the week, take a gander at these four
electronics-themed
comics which appeared in a 1961 issue of Radio-Electronics magazine.
The one on page 106 is my favorite. It reminds me of an old Bugs Bunny cartoon from
back in the 1970s, where a freeway was going to built over his rabbit hole (warren),
and Bugs thwarted all efforts by construction crews from violating his humble abode
(see "No Parking Hare"). There was another similar episode where skyscrapers were
built around his hole, but I cannot find it. The page 95 comic reflects the public's
fascination with rocket flights in an era when the first satellites were being launched,
and manned spaceflight filled the imaginations of young and old. By coincidence,
today's (October 4th) RF Cafe header logo features the Sputnik launch...
 "Iridium Communications Inc., a leader in
global voice and data satellite communications, has taken a significant step forward
in its mission to enhance connectivity. The 3rd Generation Partnership Project (3GPP)
has officially accepted Iridium's request to expand the functionality of
Narrowband Internet of Things (NB-IoT) for Non-Terrestrial Networks (NTN) into
the Work Plan for 3GPP Release 19. This marks a pivotal moment for Iridium's upcoming
service, Iridium NTN Direct?, which aims to provide unprecedented access to satellite
services via standard chipsets. What is Iridium NTN Direct?...
 The Space Race was at its peak in 1964 when
this advertisement by the
Capitol Radio Engineering Institute (CREI) Program in Space Electronics appeared
in Electronics World magazine. Although it all began in 1957 with the International
Geophysical Year, the heat was turned up that year when the USSR successfully launched
Sputnik 1, the world's first artificial satellite. President John F. Kennedy
made his famous speech before the U.S. Congress in 1961, where he said in part,
"This nation should commit itself to achieving the goal, before the decade is out,
of landing a man on the moon and returning him safely to the earth." A huge push
was made by colleges...
• Solar Cycle 25 Producing
Record High Sunspot Numbers
•
34% Huawei Revenue Hike for 1st Half Year
• Layoff
Survival Guide for These Tough Times
• Rumors of
Samsung Acquiring Nokia Fly
•
Supply Chain Sustainability's Future
 The early 1960s was an era of significant
change for the realm of in-home entertainment. Television was transitioning to color,
radio was transitioning from AM to FM, and FM radio was transitioning from monaural
to stereo. Print media was beginning to include more color in its pages. The human
sense organs and brain were being called upon to process much more information from
sources other than real-world experience. For many people, seeing the world's natural
and manmade features in color was an amazing revelation, and our household was one
of last in the neighborhood to get a color TV. My introduction to stereophonic music
does not have as much of a stark place in memory. Prior to high school, my radio
listening was AM station WNAV...
 The
International Geophysical Year (IGY) was an extraordinary scientific endeavor,
representing a global cooperative effort to study Earth's physical properties and
atmosphere. Spanning from July 1, 1957, to December 31, 1958, the IGY was timed
to coincide with a period of maximum solar activity, a factor which was thought
to significantly influence Earth's environment. The project brought together scientists
from 67 countries, transcending Cold War tensions, with the goal of advancing our
understanding of the Earth and space sciences. This extensive treatise delves into
the various aspects of this monumental event, including the research conducted,
the countries involved, key figures, industrial partnerships, the science of rockets
and satellite...
 "Physicists present a
nanometer-sized light antenna with electrically modulated surface properties
- a breakthrough that could pave the way for faster computer chips. Advances in
plasmonic resonators could lead to computer chips that are up to 1000 times faster,
thanks to collaborative efforts between German and Danish universities. These teams
have successfully modulated light antennas electrically and integrated quantum mechanics
into classical physics models, promising profound technological impacts. Today's
computers reach their physical limits when it comes to speed. Semiconductor components
usually operate at a maximum usable frequency of a few gigahertz..."
 Raise your hand if your old stereo system
had a "Loudness"
control, but you never really knew what it did - other than change the loudness
(my hand is up). Author Rudolph Jacobs addresses the subject in a technical manner
- Fletcher-Munson curves and all - in this 1963 edition of Electronics World
magazine. In a nutshell, in case you don't feel like reading the entire article,
Loudness compensates for the difference in perceived sound intensity level across
the audio frequency spectrum as the reference level is varied. That is to say, it
maintains the same perceived listening level across the audio spectrum whether you
have the volume control turned way down, way up, or in the middle - a sort of volume-dependent
equalizer.
 Transcat | Axiom Test Equipment, an electronic
test equipment rental and sales company has published a new blog post entitled "Grid
Simulators Are Smart Power Sources" that covers how to pick the right grid simulator
that best fits the needs of your project requirements. Choosing a grid simulator
for an application is a matter of understanding available functions and key operating
parameters, such as voltage, current, power, and output frequency. Grid simulators
supply AC and DC electrical power under the many conditions exhibited on an electrical
power grid and can accurately measure bidirectional power from DUTs or loads capable
of generating power. A regenerative grid simulator can manage fully four-quadrant
electrical power while returning a high percentage of power to the grid...
 The
tech-themed comic that appeared on page 59 of the February 1969 issue of
Electronics World magazine is consistent with the prevailing theme of the era
where wives and girlfriends were fairly oblivious to the meaning of technical endeavors
of their husbands and boyfriends, respectively (or not necessarily). The other comic
from that edition is reflective of the times as well, when a television was considered
to be one of the essentials of modern life. Carrying one's essentials wrapped up
in a cloth and tied to the end of a wooden pole represented the stereotypical kid
running away from home. I was a pretty rotten kid, but I don't remember ever running
away from home - probably because I knew that my parents knew that I knew...
 This could be one of those quizzes where
common items are shown close-up so they do not look familiar, and the reader's job
is to figure out what he's seeing. The montage of micrographs of antimony, cadmium
sulfide, germanium etched in argon, and germanium etched in hydrogen, appeared in
a 1962 issue of Radio-Electronics magazine. All are elements / compounds
currently (at the time and now) being researched and used in semiconductors. Knowledge
of
semiconductor physics has multiplied exponentially in the succeeding six decades
(hard to believe that much time has passed). The Massachusetts Institute of Technology's
(MIT) Lincoln Laboratory did the work shown here...
 Like most people familiar with electronics,
when
negative resistance semiconductors are mentioned, I immediately think of tunnel
diodes. Negative resistance is the characteristic where in increase in voltage across
the p-n junctions results an a decreased current. Although the tunnel diode was
invented by by Leo Esaki (Sony) in 1957, it is not mentioned anywhere in this 1969
article. Instead author Wesley Vincent (Motorola) describes the theoretical operation
of 4-layer (3 junction) semiconductors and how they can be biased to mimic true
negative resistance devices. Given that one of the most common applications of tunnel
diodes is to construct relaxation oscillators, knowing which configurations of standard
BJTs can act like...
 "Researchers have developed a method to
create a
two-dimensional silk protein layer on graphene, enhancing its potential in microelectronics,
particularly for wearable and implantable health sensors and memory transistors
in computing. This innovation offers a nontoxic, water-based, and biocompatible
system, potentially revolutionizing silk's application in luxury materials and high-tech
industries. The research opens pathways for further advancements in silk-integrated
circuits and sustainable electronic solutions. After thousands of years as a highly
valuable commodity, silk continues to surprise. Now it may help usher in a whole
new direction for microelectronics and computing..."
 This 1935 article found in Short Wave
Craft magazine quotes the
DJC radio station engineer as saying that they transmitted with
only 5 kW into the farm of directional antenna arrays, and that it was sufficient
to provide what was evidently very high quality reception to many remote regions
of the world. Adolph Hitler had become "Führer und Reichskanzler" the year before,
with plans already in the works to dominate the world. Troops invaded Poland on
September 1, 1939, officially beginning WWII. DJC's global reach was used extensively
for propaganda during the war...
|
 The newest release of RF Cafe's spreadsheet
(Excel) based engineering and science calculator is now available -
Espresso Engineering Workbook™. Among other additions, it now has a Butterworth
Bandpass Calculator, and a Highpass Filter Calculator that does not just gain, but
also phase and group delay! Since 2002,
the original Calculator Workbook has been available as a free download.
Continuing the tradition, RF Cafe Espresso Engineering Workbook™ is
also provided at no cost,
compliments of my generous sponsors. The original calculators are included, but
with a vastly expanded and improved user interface. Error-trapped user input cells
help prevent entry of invalid values. An extensive use of Visual Basic for Applications
(VBA) functions now do most of the heavy lifting with calculations, and facilitates
a wide user-selectable choice of units for voltage, frequency, speed, temperature,
power, wavelength, weight, etc. In fact, a full page of units conversion calculators
is included. A particularly handy feature is the ability to specify the the number
of significant digits to display. Drop-down menus are provided for convenience...
 One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4 million pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 225,000k per
year (in eight locations on each page, with >17k pages)...
 As with my hundreds of previous
science and engineering-themed crossword puzzles, this one for March 8, 2020,
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have built up over nearly two decades. Many
new words and company names have been added that had not even been created when
I started in the year 2002. You will never find a word taxing your knowledge of
a numbnut soap opera star or the name of some obscure village in the Andes mountains.
You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical
location like Tunguska, Russia, for reasons which, if you don't already know, might
surprise you.
 Believe it or not, many countries did - and
some still do - charge people wanting to receive over-the-air (not cable or satellite)
commercial radio and/or television programming a
wireless license fee for the privilege. Yes, this is for receiving, not transmitting,
signals. If you dared to tune in a BBC program without a license, a fee could be
expected upon detection (pun intended). The Monthly Review feature in this 1946
issue of Radio-Craft magazine reported an increase in cost to the equivalent
of $29 in 2021 money (per the BLS Inflation Calculator). Also highlighted was a
method for printing radio circuits made with conductive inks on ceramic sheets -
known today as thick-film printing. An announcement of the U.S. War Department's
18,000-tube ENIAC electronic calculating device was made as well. The electronics
field was moving quickly...
 Due to the era in which this "Electronic Puzzle Square" appeared (1945), I made a couple edits
to help prevent misinterpretation. For instance the "mfd." in question 5 is microfarad
(μF) in today's units standard. Question 4 originally had an upper case "E," which
was a typo since it should have been a lower case "e," as in the base of the natural
logarithm. When working Q7, leave the input and output terminals open when calculating
the equivalent resistance; it's not like doing a "Pi" to "Tee" attenuator conversion.
Q11 originally had "logE" where it should have been just "e." Q9 is a piece of cake.
Question 15 assumes you know the resistance per foot of #25 B&S (AWG) copper
wire, which you can find here (hint: it's 32.4 Ω/1000 ft)...
 By 1944, the U.S. and its Allied partners
were occupied full-time beating back the forces of Communism, Fascism, Socialism,
and many other 'isms.' A vast majority of active service members were men who were
either training on domestic soil or fighting on foreign soil. That left sisters,
mothers, and grandmothers to conduct a lot of the business and work production jobs
that historically had been the near sole purview of men.
Rosie the Riveter was a very familiar symbol of that new paradigm, while less
known and celebrated were the women who handled building and servicing electronics
products. I have posted many articles that appeared in magazines ...
 Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 225,000 times per year! New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company
news to be seen, RF Cafe is the place to be...
 British engineer John Sargrove was to the
production of radios what Henry Ford was to automobiles. At the time this "Robot
Makes Radios" article appeared in a 1947 issue of Radio-Craft magazine, Sargrove
had recently put his
Electronic Circuit Making Equipment (ECME) fully automated assembly line into
operation. Applying knowledge from two decades of developing methods of crating
inductors, capacitors, resistors, and interconnecting conductors using controlled
deposition of various materials on flat substrates, he was able to build 2-tube
AC/DC radios at a rate of up to three per minute, with only two ECME operators -
one at the input and one at the output. The only manual assembly required was the
installation of a potentiometer-switch, a transformer, speaker...
 Long before digital communications was widely
adopted, there was a great need for stable frequency-determining devices / systems.
That is to say, low bit error rates (BER) for digital communications are not the
sole motivation for
oscillators with low short-term and long-term stability and low levels of jitter.
One obvious need for precise frequency control is radar, in order for accurate ranging
(the second "R" in radar) and in the case of Doppler systems, for accurate radial
velocity reporting and clutter cancellation. Those capabilities existed long before
digital systems came online. Aside from radar, precise frequency was needed in order
to reduce guard band width between assigned channel assignments, thereby enabling
more broadcast stations (commercial and military) to coexist in an allotted frequency
band...
 There is still a lot of vintage ham radio
equipment in use both by the original owners and by newcomers who buy the equipment
at Hamfests and on eBay. User's manuals are hard to come by, since they often were
separated from the original gear a long time ago. Knowing how to operate, repair,
and align everything properly is still necessary, especially as the airwaves get
ever more crowded and the FCC gets more serious about prosecuting violators. Old
editions of QST are the perfect resource for locating such information.
This article covers some of the
basics of oscillators - tritet types in particular - used for CW keying. The
tritet oscillator gets is name from having been designed originally to efficiently
generate third and fourth harmonics, per James Lamb's June 1933 QST article "A More
Stable Crystal Oscillator of High Harmonic Output." ARRL members can download the
article...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers"
Smith chart design. These would make excellent gifts for husbands, wives, kids,
significant others, and for handing out at company events or as rewards for excellent
service. My graphic has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. I only make a couple bucks
on each sale - the rest goes to Cafe Press. It's a great way to help support RF
Cafe. Thanks...
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 225,000 times per year! New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company
news to be seen, RF Cafe is the place to be...
 Whenever I see advertisements for electronics
training courses, I think of the line in "Duel in the Snow, or, Red Ryder Nails
the Cleveland Street Kid," where it mentions how during the Great Depression years
the magazines were filled with ads "promising successful careers repairing radios."
That story, which ultimately became the book and movie "A
Christmas Story," was contained in Gene Shepherd's book In God We Trust: All
Others Pay Cash. Jean Shepherd was a radio announcer and story teller who first
read "A Christmas Story," on his WOR (New York City) show in 1970. You can listen
to a 1974 broadcast in the YouTube video embedded below. This reading is slightly
different than the one given to me by a guy who actually recorded it on tape...
 Judging by some of the letters written to
magazines by their readers,
obtaining parts referenced in many construction articles proved difficult or
impossible to procure. Ziff-Davis, a major publisher in 1940 as well as today, ran
this notice in a 1940 issue of its Radio News magazine offering advice
as to how one might go about getting everything needed. Unlike nowadays where nearly
every available source worldwide can be found on the World Wide Web, back then searching
could be - and too often was - a long, slow process. Just finding a phone number
or mailing address for a potential supplier presented a major obstacle to anyone
without a collection of catalogs and magazines - or at least knowing someone who
did. Imagine needing ten non-standard parts and having to write letters to manufacturers
and/or distributors trying to located critical component...
 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...
 Call forwarding, call waiting, call holding,
speed dialing, conference calling, all of these features are taken for granted with
mobile phone and VOIP phone service and are included in the base service package.
It will cost you extra if you subscribe to a local legacy POTS (Plain
Old Telephone Service) provider. What is standard now was considered ground-breaking
technology in the early1960s when this article appeared in Popular Electronics
magazine. When phone calls were processed via human operators manipulating patch
cords and then electromechanical relays, it was enough to simply place a successful
call and not be interrupted or disconnected. Once transistorized circuits entered
the scene, much more was possible, and phone system engineers were quick to exploit
the technology. Sophisticated decision making requires both logical circuits and
a form of memory. Logic could be provided using hard-wired diode steering...
 Wirewound inductors (as most are) can be
mysterious entities even when you are familiar with their many interdependent physical
and electrical properties. Because of interwinding capacitance and a sometimes (when
a large number of turns are involved) rather significant series resistance, the
equivalent circuit model gets quite complex - literally in a mathematical sense.
If you have the luxury of staying far away from the
self-resonant frequency (SRF) of the coil, your component will behave very much
like an ideal inductor, that is, XL = 2πfL. This 1966
Electronics World magazine article delves into what causes inductors to
act like parallel and/or series resonant tank circuits, how to avoid the inconvenience
of unwanted resonances, and how to exploit resonances in your favor. You'll also
learn (if you don't already know) the distinction between a "choke" and an inductor...
 Since 2000, I have been creating custom
technology-themed crossword puzzles for the brain-exercising benefit and pleasure
of RF Cafe visitors who are fellow cruciverbalists. The jury is out on whether or
not this type of mental challenge helps keep your gray matter from atrophying in
old age, but it certainly helps maintain your vocabulary and cognitive skills at
all ages. A database of thousands of words has been built up over the years and
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc. You will never find a word taxing your knowledge of
a numbnut soap opera star or the name of some obscure village in the Andes mountains.
You might, however, encounter the name of a movie star like Hedy Lamarr or a
geographical location like Tunguska, Russia, for reasons which, if you don't
already know, might surprise you...
 Even though my fingers stop working when
exposed to temperatures below freezing, I love the northern climate - four full
seasons, snow, iced-over lakes, migrating birds, fiery autumns, cool summers, the
whole experience. Having the option of not participating in the cold outdoor environs
is what makes it good. However, the
U.S. Army Signal Corps guys pulling duty in Alaska during World
War II did not have that luxury. As told by radio engineer Major Colvin in
this story from a 1945 edition of ARRL's QST magazine, winter life in Alaska at
-40° was a real challenge. It was a world where Prestone antifreeze froze, the sun
shone only a few hours a day, vehicles had to be left running 24/7 or risk not being
able to be re-started, and mile-long treks between buildings was common. There were
no snowmobiles. The success of the communications station...
 We
are moving into the colder days of the year in the northern hemisphere. The normal high
temperature here in Erie, Pennsylvania is around 49°F (35° today with snow on the ground
for the last three days). It is the time of year that causes those less appreciative
of cold weather to conjure up memories of warm summer days with green leaves on tree
branches and colorful flowers in the garden. For those of you like me who actually prefer
the cooler weather, this
Carl & Jerry story about making snow by blasting clouds with ultrasonic energy
just adds to my appreciation of the onset of winter and visions of a white Christmas.
To date there has been no major, efficient progress in the field of snowmaking or rainmaking
(other than seeding clouds with silver iodide). Ski resorts still need sub-freezing weather...
 The old adage about pioneers taking the
arrows is true in many realms - not just the exploration and settling of the wild
west. This story entitled "Sparks
on Ice" recounting the trials and tribulations of the troops who installed and
debugged the first arctic directional beacons appeared in a 1945 issue of Flying
Age magazine. "Sparks" (or "Sparky") was an endearing nickname given to early radio
operators who used spark gap transmitters to send out their Morse code messages.
It stuck around for many years after better transmitter systems were developed -
although it is not very often heard today. The most interesting part of Mark Weaver's
article is a discussion of the many atmospheric phenomena that affect radio waves
of various wavelengths. A lot of smart people - enlisted, commissioned, and civilian
- sacrificed mightily...
 It's a pretty good bet that most RF Cafe
visitors are not overly interested in
vacuum tube testers. Today they are collectors' items with some actually still
being used for maintaining vintage electronics gear; however, in the days before
semiconductor components they were the life blood of service men. Because tubes
(aka "valves" in other parts of the world) are by nature one of the most vulnerable
parts of any product in which they are used, often the first step in troubleshooting
a radio, television, record player, etc., was to test suspected tubes for sub par
performance. As mentioned often in Mac's Radio Service Shop stories, customers balked
at service centers charging for their expertise but didn't mind as much paying for
replaced components. That meant mark-ups on vacuum tubes comprised...
 Less than half a decade had passed when Radio &
Television News editor Oliver Reed wrote this piece extolling the
virtues of the transistor and how "it may well revolutionize the entire
electronics industry." If you have followed a lot of my postings from the
vintage electronics magazines here on RF Cafe, you are well aware that there was
a lot of resistance to and doubt about the future of semiconductors. Naysayers
had the same kind of reaction to the advent of the horseless carriage
(automobile) and locomotive, relativity and quantum mechanics, and even curative
medicines. Point contact transistors were still largely in use, but were costly
compared to the relative simplicity and low cost of junction transistors once
the manufacturing details were worked out - which, as we now know, happened very
rapidly. By 1965 the process was so refined that Gordon Moore...
The newest release of RF Cafe's spreadsheet
(Excel) based engineering and science calculator is now available -
Espresso Engineering Workbook™. Among other additions, it now has a Butterworth
Bandpass Calculator, and a Highpass Filter Calculator that does not just gain, but
also phase and group delay! Since 2002,
the original Calculator Workbook has been available as a free download.
Continuing the tradition, RF Cafe Espresso Engineering Workbook™ is
also provided at no cost,
compliments of my generous sponsors. The original calculators are included, but
with a vastly expanded and improved user interface. Error-trapped user input cells
help prevent entry of invalid values. An extensive use of Visual Basic for Applications
(VBA) functions now do most of the heavy lifting with calculations, and facilitates
a wide user-selectable choice of units for voltage, frequency, speed, temperature,
power, wavelength, weight, etc. In fact, a full page of units conversion calculators
is included. A particularly handy feature is the ability to specify the the number
of significant digits to display. Drop-down menus are provided for convenience...
This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, Baseball Caps, and more, all sporting my amazingly clever "RF Engineers - We Are the World's Matchmakers"
Smith chart design. These would make excellent gifts for husbands, wives, kids,
significant others, and for handing out at company events or as rewards for excellent
service. My graphic has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. I only make a couple bucks
on each sale - the rest goes to Cafe Press. It's a great way to help support RF
Cafe. Thanks...
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 225,000 times per year! New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company
news to be seen, RF Cafe is the place to be...
 For two decades, I have been creating custom
engineering- and science-themed crossword puzzles for the brain-exercising benefit
and pleasure of RF Cafe visitors who are fellow cruciverbalists. The jury is out
on whether or not this type of mental challenge helps keep your gray matter from
atrophying in old age, but it certainly helps maintain your vocabulary and cognitive
skills at all ages. This September 29, 2019, puzzle uses a database of thousands
of words which I have built up over the years and contains only clues and terms
associated with engineering, science, physical, astronomy, mathematics, chemistry,
etc. You will never find a word taxing your knowledge of a numbnut soap opera star
or the name of some obscure ...
 I found this
Bridge Circuit Quiz in my stack of vintage Popular Electronics magazines.
Your challenge here is to decide what the main function of each type of bridge circuit
is. Most bridge circuits are designed such that a component of unknown value is inserted
into one of its four branches, and then one or more variable components of known values
are adjusted to balance the bridge and thereby create a minimum (null) between opposite
(circuit-wise) nodes. Admittedly, I did not fare well, but it is because I do not recall
having the names associated with many of these bridge circuits. Of course nearly everyone
is familiar with the Wheatstone, Kelvin, and Wien bridges. Hyperlinks...
 A few days ago, I was perusing an April 1973
edition of Popular Mechanics magazine, when I ran across the following
full-page ad with a U.S. Air
Force enlistment aptitude test. Take the test, and if you get the same answers
as the geniuses that created the ad, you're a shoe-in for a great career in the
USAF! Uncle Sam wants you, bay-bee. I did the first two tests and got what they
got for answers. Then I took the third test - the one with the little folded house
- and was shocked at what I found. You take the three tests, and see if you think
something is amiss with the last one. Look way down at the bottom of the page for
my conclusion...
 QST reader George P. Orphan, KG4DXJ,
wrote in the February 2020 issue's "Letters from Our Members" column about an episode
of the old "Hazel" television show entitled, "Stop Rockin'
Our Reception," where interference on the Baxters' TV set was blamed on the
"shortwave set" operated by a teenager, Bruce, who had recently moved in down the
street. George Baxter, the household's impulsive lawyer father, was convinced enough
that Bruce, a friend of his son, Harold, was responsible that he paid a visit to
the boy's house and spoke to his father about it. Bruce politely informs Mr. B
that unless his television was was manufactured before 1950, it was unlikely that
his operations on the 10-meter band would be causing the interference, but it fell
on deaf ears. Shortly thereafter, a power company investigator was seen walking
around the front yard with a box bearing a loop antenna on the top of it. At the
request of Bruce's father...
 According to Wikipedia, The Navy's USS Compass
Island was one of two ships, the other being USS Observation Island, converted and classified
as navigational research test vessels under the Polaris Missile system budget. As reported
here, the newfangled
radio sextant tracks the position of the sun or moon to provide location accuracy
much better than the best traditional compass. Remember that in 1959 there was no satellite
navigation, and in the middle of the ocean land-based transmitters were useless as radio
bearing references. Inertial navigation systems could not hold their calibrations in
the harsh physical environment of stormy seas. This radio sextant system is fine as long
as the sun and/or moon is high enough in the sky to have antenna pointing access to one
or...
 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... |
