|
 Thévénin's Theorem is a fundamental concept
in electrical engineering that simplifies complex linear electrical networks into
simpler, equivalent circuits. It's named after the French engineer Léon Charles
Thévénin, who formulated the theorem. Thévénin's Theorem is particularly useful
for analyzing and solving circuits with multiple components and sources. The theorem
states that any linear electrical network with multiple sources and resistive elements
can be replaced by a single voltage source (Thévénin voltage) in series with a single
resistor (Thévénin resistance). This simplified equivalent circuit is called the
Thévénin equivalent circuit. This article from a 1962 issue of Radio-Electronics
magazine presents a great introduction to the basics of Thévénin's Theorem...
 Ummm... was this really a "space walk?"
If so, then I "sky walked" when I climbed to the top of my 6-foot wooden ladder
yesterday. "The world's first commercial space walk, performed by billionaire
Jared Isaacman and SpaceX engineer Sarah Gillis, tested new technology and was practically
flawless. It wasn't a small step - more a clamber, really - but as billionaire entrepreneur
Jared Isaacman
climbed partway out of a SpaceX Dragon capsule located nearly 740 kilometers
above Earth on early Thursday morning, he made a giant leap into spaceflight history.
That's because Isaacman is a private citizen who is flying in a commercial spacecraft
on a voyage he paid for - not a government-agency...
• Staten Island Technical
High School Helps License Hams
• China to Launch
Satellites to Compete with Starlink
•
$15B RF & Optical Metamaterials Market by 2034
•
Congress Grills FCC on ACP, Mapping, Broadband Funding
• Vote for
2024 Global
Electronics Awards
 With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols available
for RF, analog, and digital system and schematic drawings! Every object has
been built to fit proportionally on the provided A-, B- and C-size drawing page
templates (or can use your own). Symbols are provided for equipment racks and test
equipment, system block diagrams, conceptual drawings, and schematics. Unlike previous
versions, these are NOT Stencils, but instead are all contained on tabbed pages
within a single Visio document. That puts everything in front of you in its full
glory. Just copy and paste what you need on your drawing...
 Popular comic strips (aka "funnies") in
the 1930s and 1940s featured numbskulls, ne'er-do-wells, and simpletons. There was
usually one character in the strip's cast that was smart - at least in a relative
way if not absolute. Being familiar with some of the old comics like Blondie, Barney
Google, Krazy Kat, Beetle Bailey, Gasoline Alley, etc., I can see a definite relationship
between the story line of "Entertaining
Uncle Oscar" and the comics of the era in this short story that appeared in
a 1939 edition of the ARRL's QST magazine. As you might guess, the feller
named "Ham" is the smart one. Q: Is it irony, coincidence, or premonition on the
author's part that the uncle's name is the same as the ARRL's OSCAR series of Orbiting
Satellite Carrying Amateur Radio(s)?
 "A team of scientists has unlocked the potential
of 6G communications with a new
polarization multiplexer. Terahertz communications represent the next frontier
in wireless technology, promising data transmission rates far exceeding current
systems. By operating at terahertz frequencies, these systems can support unprecedented
bandwidth, enabling ultra-fast wireless communication and data transfer. However,
one of the significant challenges in terahertz communications is effectively managing
and utilizing the available spectrum. The team has developed the first ultra-wideband
integrated terahertz polarization..."
 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 about0k per
year (in eight locations on each page, with >17k pages)...
 This
electronics-themed crossword puzzle was published in a 1963 issue of Electronic
World magazine. Crosswords were a fairly standard feature in magazines up through
the late last century. Keeping with tradition , every week (usually) I create an
engineering-themed crossword puzzle that uses a hand-selected collection of a couple
thousand words and clues from a dictionary I built over the last 15 years. Unlike
most crosswords seen in technical and hobby publications, RF Cafe Crosswords contain
only relevant words - never filling in with the names of movie stars, obscure countries,
or portmanteaus relating to social oddities...
 According to author R.R. Freeland, manufacturing
processes for radio-quality
manmade crystals saw major improvements toward the end of World War II.
At the time, the process was highly manual-intensive, as can be seen in this really
nicely done 1940s video titled "Crystals Go to War." Prior to the use of crystals
as frequency-determining devices, inductor-capacitor (LC) tank circuits were the
dominant configuration. There were actually other frequency-determining schemes
like spark gaps and even vibrating mechanical reeds. As you might guess, anything
less than a crystal suffered from higher short-term and long-term stability, drift
over temperature, microphonics, and the phase noise - composed of multiple effects
like shot noise, i/f noise, etc. - was relatively terrible...
 Making and using LCD displays is child's
play compared to what was required to design, manufacture, and implement
cathode ray tubes for televisions, test equipment, security and industrial monitors,
and in the end days for CRTs, computer monitors. That is not to say the evolution
of LCD displays was an easy endeavor, just that now novice hobbyists can easily
design an LCD display into a project. Such was not the case with CRTs, even after
the tube itself was made available. Designing deflection coils and the driver circuitry
required, even if the person is not aware of it, to account for relativistic effects
due to the speed and mass of electrons in the beta ray stream used to cause the
fluorescent dots on the face of the tube...
 Tennode,
of Dublin Irvine, California, provides sales and distribution services, is a private
labeling company. Per their website: "Tennode
aims to provide the best quality products in a timely manner to customers in the
telecommunication, data center, automotive, aerospace, and defense industries. Our
user-friendly website supports developers, and responsive tech support is always
available. Tennode prioritizes top-tier products, spanning network infrastructure
and cutting-edge devices. Swift product delivery is our hallmark, ensuring customer
satisfaction. Our user-friendly platform supports developers, backed by responsive
tech support. Diverse supply channels..."
 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...
 Simmonds Precision Products (bought by Goodrich),
a company in Vergennes, Vermont, which I worked for for a couple years prior to
quitting to attend the University of Vermont full-time to finish my electrical engineering
degree, had as one of their main products
capacitance-based fuel measurement systems for military and commercial aircraft.
As was common in the era (up through the late 1980s), they made not only the capacitance
probes and associated electronics, but also the cockpit displays and power supplies.
Being a test technician at the time, I got a pretty good exposure to the complexities
of such a fundamentally simple principle as using the dielectric constant of the
fuel to vary the capacitance between a set of plates. Capacitance...
 In the telecommunications industry, the demand
for higher data rates and more efficient networks has led to an increased focus
on the quality and performance of wireless systems. One of the critical challenges
affecting network performance is
Passive Intermodulation (PIM). PIM is an unwanted phenomenon that occurs in
wireless communication systems, leading to signal degradation, reduced data throughput,
and interference. Understanding the causes of PIM and implementing mitigation techniques
is essential to maintaining high-quality network performance. PIM is a form of distortion
that occurs when two or more high-power signals mix and generate additional frequencies
within a passive component, such as connectors, cables, antennas...
 What better way (that can be done in an
office or lab environment) is there to end a long week of work than with a few
electronics-themed comics - in this case from a 1961 issue of Radio-Electronics
magazine (he asks rhetorically)? As can be seen by viewing some of the other comics
of the era, these are concerned with the two biggest crazes of the day - television
and stereophonic systems. In particular, there was an ongoing low-level war persisting
between homeowners and servicemen. It was and is no different that what exits today
between owners and repair services for auto, appliance, computer, and other forms
of personal possessions. I took the liberty of colorizing all of the comics, so
if something looks odd, don't blame the artist ;-)
 Transcat | Axiom Test Equipment, an electronic
test equipment rental and sales company has published a new blog post that covers
how
battery test systems can check the health of batteries of all shapes and sizes.
We break down the capabilities of various battery test systems and how they can
evaluate voltage, current, power, and energy storage capacity over an expected operating
lifetime. A battery test system with sufficient measurement capabilities and control
functionality can evaluate a battery under test or BUT for its amount of self-discharge
under different operating conditions, such as changes in load and temperature. Finding
a suitable battery test system...
 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...
 "A team of electrical and computer engineers
at Shanghai Institute of Microsystem and Information Technology, Chinese Academy
of Sciences, working with one colleague from City University of Hong Kong and another
with Fudan University, has developed a new
two-dimensional, low-power-consumption field-effect transistor (FET) that could
allow smartphones to need recharging less often. In their paper published in the
journal Nature, the group describes how they overcame problems with high gate leakage
and low dielectric strength that have stymied..."
 In the late 1960s when this story appeared
in Electronics World magazine, the television industry was just getting
started with building out
infrastructure for cable TV delivery to homes. All signals were analog of course,
and there was very little digitization of receiver circuitry in TV sets; i.e., synthesized
tuners. A large percentage of televisions used vacuum tubes and relied on twin lead
transmission cable between a rooftop antenna and the back of the set. The plug-in
connection of vacuum tubes often caused problems due to high resistance contacts
between the tube pins and the sockets, and could also suffer from PIM signals generated
by corroded contacts. Unshielded twin lead, which has the advantage of much lower
signal loss than coax, was a prime source of interference pick-up, especially if
a long run was used. Cable TV used a 72-Ω coaxial cable between the street connection
and the receiver, so it was pretty much immune to interference. Mac's trusty sidekick,
Barney, solved an interference issue caused by a combination of a loose tube in
on neighbor's TV set and a long twin lead cable used by the guy across the street...
 The discovery of the
cosmic microwave background radiation (CMBR) is one of the most significant
breakthroughs in modern cosmology, providing crucial evidence for the Big Bang theory
of the universe's origin. In the early 1960s, a team at Bell Telephone Laboratories,
including Arno Penzias and Robert Wilson, unintentionally stumbled upon this discovery
while working on a very different project. They were using a large, horn-shaped
antenna, often referred to as the "Holmdel Horn Antenna" or the "Sugar Scoop" due
to its shape, for radio astronomy experiments. Their initial goal was to study radio
emissions from various sources in space, but they encountered an unusual form of
interference that they could not explain or eliminate...
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...
 "Gotonomi, a UAV satellite connectivity
solutions provider, has announced the completion of further successful flight trials
and the opening of orders for production units of all variants of its
UAV satcom terminals at Commercial UAV Expo 2024 in Las Vegas. The launch marks
a significant milestone, transitioning from pre-production flight development kits
to type-approved, commercial terminals, enabling scalable beyond visual line of
sight operations (BVLOS) for drone operators wishing to offer inspection, surveillance,
and delivery services. Following extensive verification testing, including flight
trials..."
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. We are pleased to announce
the model
AMP2074P-2KW Pulse Amplifier. It is designed for pulse, EMC/EMI Mil-Std 461
and pulse radar applications. Provides superb pulse fidelity up to 100 μsec
pulse widths. Duty cycles to 10% with a minimum 63 dB gain. Available monitoring
parameters for forward/reflected power in watts & dBm, VSWR, voltage, current,
temperature sensing for outstanding reliability and ruggedness in a compact 4U chassis...
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 is a brief accounting of the
history of semiconductor electronics. It was generated entirely based on specific
prompts to ChatGPT, and is presented without editing; i.e., it may contain errors.
I was surprised to see how far back investigations into semiconductors reaches -
all the way to Michael Faraday. It mentioned the Silicon Valley "Traitorous Eight,"
which I had not known about. I will asked ChatGPT for more detail on that, and will
post it sometime in the next day or so. The chart on the left is from an IEEE Spectrum
magazine story entitled, "The Ultimate Transistor Timeline..."
 To some degree, I have done programming
in Turbo Pascal, Delphi, Visual Basic, JavaScript, and PHP. Only one of them (JS)
makes more than a slit on this IEEE chart of
2024's top languages.
"Welcome to IEEE Spectrum's 11th annual rankings of the most popular programming
languages. As always, we combine multiple metrics from different sources to create
three meta rankings. The 'Spectrum' ranking is weighted towards the profile of the
typical IEEE member, the 'Trending' ranking seeks to spot languages that are in
the zeitgeist, and the 'Jobs' ranking measures what employers are looking for..."
 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 average0,000 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...
 As with so many aspects of electronics, physics,
economics, medicine (well, maybe not medicine), the basics do not change a whole
lot since first being discovered. If you are a newcomer to the world of electronics
and are trying to come up to speed on
transistor construction and operation, even this article that appeared in a
1968 issue or Radio-Electronics magazine will be useful to you. Figure 1
reminds me of a situation I witnessed while working as a technician at Westinghouse
Oceanic Division, in Annapolis, Maryland. If you've heard this before, please indulge
me. One of the managers there, who was not a degreed engineer...
 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...
|
 Conventional current flow (as opposed to
electron current flow) is a foundational concept in the study of electricity and
electronics, and refers to the flow of electric charge from the positive terminal
of a power source to the negative terminal. This convention traces back to the early
days of electrical science when the nature of electric charge was not yet fully
understood. This treatise will explore the historical context, physical principles,
and practical implications of conventional current flow, along with its relevance
to modern electrical engineering. The idea of conventional current was established
long before the discovery of the electron. In the 18th century, Benjamin Franklin
proposed the theory that electric charge flowed from a region of excess to one of
deficiency, and he arbitrarily designated the flow from "positive" to "negative...
 Mr. Lothar Stern was a fairly prolific
publisher of books and magazine articles during his long career at Motorola. What
remains of the Motorola brand these days is mostly associated with cellphones, with
the venerable Razr model being the most famous. China-based Lenovo now owns even
that aspect of Motorola (after a short-lived ownership by Google). In its heyday
prior to the 2000s, Motorola was a major manufacturer of analog, RF, and digital
semiconductors (including microprocessors), radios, televisions, telephones, vacuum
tubes, medical equipment, and more. It is interesting to note that the issues referenced
in this article regarding
technical terms are not even relevant...
 Once again, Hugo Gernsback's precognitive
talent is apparent, these six decades hence since the publishing of this "Radio
Power" editorial in his Radio-Electronics magazine, this time on the
subject of wireless power transfer. Many schemes have been proposed for transferring
power through the ether, using both magnetic and electric fields, at a wide range
of frequencies. Wireless chargers are common for portable personal devices like
cellphones and hearing aids. The power levels and close proximity of the transmitter
and receiver make such applications reasonable, but always less efficient (i.e.,
wasted power) than by direct conductive cable means. One of the most extreme systems
proposed for wireless power transfer is to use space-based solar collectors and
reflectors to beam a concentrated ray of power to Earth stations...
 Are you violating patent laws in your basement?
Patent laws have changed since this article was published in 1966, but the tenets
are basically the same - do your due diligence on prior work assignment before publishing
any publicly accessible product (print or physical). Since part of Popular Electronics'
raison d'être is to provide circuits for hobbyists to build and benefit from, the
lawyer who wrote this piece focuses on such applications. He claims, at least according
to 1960 patent law, "There are court decisions which hold that experimental use
of a patented invention for the sole purpose of gratifying curiosity or a philosophical
taste, or for mere amusement, is not an infringement." HOWEVER, before you conclude
that this must still be the case, read this synopsis from the Ius Mentis website
titled "Crash Course on Patents..."
 Diathermy, radio frequency (RF), and microwave
heating are techniques that use electromagnetic waves to generate heat for medical
and industrial applications. Over the years, these methods have evolved significantly,
impacting healthcare and industrial processes. This treatise explores their origins,
development, and modern applications in both medical and industrial settings. Diathermy,
derived from the Greek words "dia" (through) and "thermos" (heat), refers to deep
heating of tissues using high-frequency electrical currents. It was first introduced
by German physician Karl Franz Nagelschmidt in the early 20th century...
 More
electronics-themed comics here, this time from a 1961 issue of Radio-Electronics
magazine. Based on the page 63 comic, it seems maybe the dumbing down of kit builders
began earlier than I thought. Actually it was heyday of electronics kit builders,
when a do-it-yourselfer could expect to save money by assembling a radio, television,
oscilloscope, public address system, and many other such items, himself for a something
comparable in quality and features to an off-the-shelf equivalent, or to pay about
the same price but have a kit with higher quality and/or more features. The page
88 comic has the doc griping about interference with his diathermy machine (which
induced heating in human tissues via RF energy) by TV sets...
 San Francisco Circuits has published a new
article on
High-Speed Circuit Design for Modern Circuitry, focusing on signal integrity
across various frequencies. High-speed circuit design demands precise attention
to signal integrity, from 1 MHz to gigabit levels. The article covers essential
design techniques and considerations for maintaining signal quality and avoiding
issues such as reflections and cross-talk. It highlights best practices for different
speed ranges, including practical tips for optimizing PCB layout to handle high-speed
signals effectively. Explore the fundamentals of high-speed circuit design and gain
insights into optimizing your designs...
 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...
    Incredibly, 23 years have passed
since the extremist Islamic attack on American soil on the morning of
September 11, 2001. Nearly 3,000 citizens died that day. World leaders have
embarked on a path of colonizing our homelands with groups of people that are known
to harbor sympathies for the terrorists.
 They dwell amongst us now and
mean to do us harm when opportunity presents itself - which it has on numerous occasions
in the past many years. Never forget the people who died in the burning towers,
the Pentagon, and the airplanes, and those left behind to grieve and get on with
life. Never forget the police and military members who fought - and some died -
to keep us safe and free. Never forget the rotten politicians who imperil our existence
with their selfish agendas.
 "Researchers at the University of Rochester
have employed
surface acoustic waves to tackle a major challenge in the development of a quantum
internet. In a new study published in Nature Communications, scientists from Rochester’s
Institute of Optics and Department of Physics and Astronomy describe a technique
for pairing particles of light and sound that could be used to faithfully convert
information stored in quantum systems - qubits - to optical fields, which can be
transmitted over long distances. What are surface acoustic waves? Surface acoustic
waves are vibrations..."
 A lot of innovation went into perfecting
telegraph keys. The earliest keys were the familiar "straight key" tapping type
where the operator uses a single finger to close a set of contacts that "keyed"
the transmitter for a burst of RF energy. The length of each "dit" or "dah" was
determined by the operator's dwell time. It didn't take long for someone to improve
on the scheme by designing keys that assured an adjustable, constant length for
a dit or a dah. Poor quality transmitters with lousy rising and falling edge signatures
at the beginning and end, respectively, of a CW (continuous wave) pulse made matters
worse...
 Filters has always been one of my favorite
topics. I gained a real appreciation for and understanding of them when drudging
through the mathematics behind the curves in college courses. BTW, for anyone out
there thinking about taking up engineering as a career; i.e., getting an engineering
degree, it is vitally important that you fully comprehend the concept of Laplace
and Fourier transforms because when you get to the point that you need to employ
them in your primary classes, having to struggle with the basic math while learning
to apply it to circuits, mechanics, etc., will almost surely cause you to fail.
Anyway, this article from a 1969 issue of Electronics World magazine does
a nice job of introducing the four fundamental
filter pass types (not including all-pass) and discussing...
 The "News Briefs" column in a 1961 issue
of Radio-Electronics magazine included an item which might cause modern
day feminists to develop a case of the vapors. Miss Marlene Schmidt, of Stuttgart,
Germany, was crowned with the title of
Miss Universe 1961. The rub: She had already earned a Master's degree in engineering,
and was working in research for an electronics and radio company. Also, in the news
was a new "ultraminiature" transistor from RCA, and Canada was on the verge of commissioning
is first stereo FM radio stations. Speaking of FM, the FCC in the U.S. proposed
new rules on the physical distance...
 European Microwave Week (EuMW) 2024, will
take place from 22 to 27th September 2024 in Paris this year. The event is Europe's
largest event for the RF and microwave industry. The 27th annual EuMW will see industry
leaders and influencers gather to discuss the latest technologies. Paris, known
as the "City of Light," will provide a mix of historic charm and modernity that
will be a wonderful experience for all those attending. This year, EuMW will feature
a wide range of conferences, forums, and exhibitions. Attendees can look forward
to a week full of discussions, networking opportunities, and deep dives into the
latest advancements. (Tip: steer clear of the
violent immigrants on the street, and don't swim in the
River Seine)
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 average0,000 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...
• Silicon
Content Peaking at 25%
•
ARRL Teachers Institute on Wireless Technology Adds 3rd Level
•
Germany's EV Sales Sink 37% as Subsidies End
• Harnessing Data Paramount to
Reshoring Chip Industry
• AI
Factories Are Hot New Real Estate
 Integrated circuits (IC's) were newcomers
to the world of electronics in 1969. Most people, it is probably safe to say, had
no idea what an integrated circuit (IC) even was. At the time, many experienced
design engineers - perhaps especially experienced design engineers - had no formal
training on the fabrication of integrated circuits. After all, assuming an engineering
student graduated at the age of 22 years old and was in 1969 say, 30 years old,
he or she would have begun junior level classes about 12 years earlier - 1957 for
the sake of argument. Given that Jack Kilby applied for the patent on his ground-breaking,
world's first integrated circuit...
 If you are not familiar with "The
Traitorous Eight" in Silicon Valley history, this account should prove interesting.
It was generated entirely by the ChatGPT AI engine. My fairly extensive experience
with ChatGPT is that it is generally very reliable, especially the 4.0 version with
its much more current database. Trust, but verify, though, for critical work. Shockley
Semiconductor Laboratory: The Origin The Origin William Shockley, a Nobel Prize-winning
physicist, co-invented the transistor at Bell Labs in 1947. After leaving Bell Labs,
he sought to commercialize transistor technology and chose Palo Alto, California,
as the location for his new venture...
 These "What's
Your EQ?" (electronics quotient)challenges that appeared in Radio-Electronics
magazine are sort of the electronics enthusiast version of The Old Farmer's Almanac
"Old and New Mathematical Puzzles." Whereas the OFA puzzles could be on any subject
- sometimes including electricity - the RE puzzles are typically based on circuit
analysis and troubleshooting issues. Two of this month's problems are new versions
of old themes. Any time you see a schematic with series and parallel combinations
of components (usually of the same kind), the first thing to do is attempt to redraw
it in a more familiar configuration. The Black Box problems often have more than
one solution; in this instance, at least three "correct" answers were submitted.
The "Over the River" puzzle is reminiscent of an OFA type puzzle. Have fun.
ISM Band Passive RF Products
from IPP
 Innovative Power Products is proud to introduce
new
passive power products for ISM bands used in industrial, scientific, medical,
and other applications. These 90-degree hybrid couplers cover the 902 - 928 MHz
and the 2.4 - 2.5 GHz bands with power ratings up to 1,000 watts CW. IPP
also provides in-phase combiners/dividers, RF terminations, directional couplers,
baluns, and single-ended impedance transformers in the ISM bands. Applications include
all industrial, scientific, and medical equipment requiring highest quality, performance,
reliability components...
 KR Electronics has been designing and manufacturing custom filters
for military and commercial radio, radar, medical, and communications since 1973.
KR Electronics' line of filters
includes lowpass, highpass, bandpass, bandstop, equalizer, duplexer, diplexer, and
individually synthesized filters for special applications - both commercial and
military. State of the art computer synthesis, analysis and test methods are used
to meet the most challenging specifications. All common connector types and package
form factors are available. Please visit their website today to see how they might
be of assistance. Products are designed and manufactured in the USA.
 Bell Telephone Laboratories developed the
T1 system (Transmission
System 1) in the late 1950s and early 1960s as a pioneering digital transmission
system that revolutionized telecommunications. It was the first widely implemented
digital carrier system, laying the foundation for modern digital communication networks.
As reported in this October 1961 issue of Radio-Electronics magazine "News
Briefs" column, theT1 system was still in the development and installation phase,
while public T1 service would begin the next year. It facilitated 24 voice channels
over an existing twisted pair of copper wires, where before only a single call could
be handled per pair. Also mentioned was a shortage of TV sets as people clamored
for the improved, transistorized color...
 Hewlett Packard introduced
their electronic
HP-35 Scientific Calculator in 1972. It was not the world's first pocket-size
electronic calculator - that distinction went to the Busicom LE-120A. However it
was the first to be designed for the science, engineering, and financial communities
with its many built-in math functions. Use of Reverse Polish Notation (RPN) might
have scared off many would-be users who were easily confused by anything other than
the traditional notation (algebraic) that mimics written form; i.e., 2 + 3 = 5 (ALG),
as opposed to 2 3 + [=] 5 (RPN). Wisely, HP made both modes selectable...
 Everything is relative... just ask Albert
Einstein. The use of terms like "contemporary," "modern," etc., in the titles of
books has always annoyed me. They would be okay if the titles also included the
year or at least the decade to which the claim applies. Not quite as nefarious is
the claim of "high frequency" when describing electronics components since it is
safe to assume that most readers understand the era to which it applies. To a lesser
extent that goes for "high voltage" and "high current." This 1964 advertisement
for
Motorola's Oxide-Passivated Silicon Annular Transistors appeared in Electronics
magazine touting the high frequency capability for switching and RF amplification...
 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 1960 Popular Electronics
magazine episode entitled "Two Tough Customers," creator and author John T.
Frye has 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...
 If you're a newcomer to the game, it may
seem that radio theory already has enough mystery without adding more. True, the
technical journals - even the ARRL's QST magazine, sometimes - do make
it a mysterious subject with their textbook language and complex notations. Radio
isn't really any more mysterious or complex than many a detective story - at least
not after you've read the last page and know "who-dunit." The difference lies in
the method of presentation. There may be some utility, then, in the idea of presenting
radio fundamentals in the manner of detective fiction. That's what this is - a series
of radio lessons in the guise of a
detective-mystery
yarn. Instead of human characters we'll use another kind - but we'll try to make
the characterizations true...
 It is Labor Day here in the U.S., so most
folks are enjoying a day off. I, of course, work on RF Cafe every day since expectations
for new content are different depending on a website visitor's country's norms.
These three
electronics-themed comics appeared in a 1960 issue of Radio-Electronics
magazine. All are related to television, which was a big thing back in the day since
it was a relatively new addition to many households. Today, everyone has effectively
a TV in his/her pocket or purse. It almost never requires service, and has excellent
reception just about everywhere. Our forebears have provided a mighty service through
hard work and dedication. I took the liberty of colorizing the original black and
white line drawings...
 Satellite evolution occurred at a rapid
pace once Sputnik and Echo were successfully launched in the late 1950s. Sputnik
was a simple beacon transmitter whose signal was used to measure orbital and atmospheric
properties and their effects on radio signals. Oh, and also to announce to the world
that the USSR had accomplished the world's first satellite mission - I'd brag, too.
Explorer 1, the first U.S. satellite, launched the following year, measured
and broadcast Van Allen Radiation Belt data. This Electronics World magazine
article appeared about a decade into the satellite aspect of the "Space Race." By
then, a couple dozen satellites were circling (well, more accurately ellipticalling[sic]
the earth, and they were active transponders that received on one frequency, then
re-transmitted the amplified signal...
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