See Page 1 |
2 |
3 |
4 | of the June 2023 homepage archives. Friday the 30th
 Thought experiment: Just because the March
1969 issue of Radio−Electronics magazine announced in the "News Briefs"
column the passing of
Professor Erwin Schrödinger, does that mean he's really dead? Was his world−famous
cat with him at the time? I'm asking for a friend. In other news, an account of
what seems to be a grossly inhumane medical experiment of the type Josef Mengele
might have performed during World War II is reported whereby a 700 Hz
(yes, 700 cycles per second) signal of undisclosed power level was imposed on a
patient's brain in lieu of traditional anesthesia gas during a stomach operation.
No word of the long-term effects are included. It obviously did not catch on as
an alternative method. Many other breaking news items are included as well...
 Withwave is a leading designer and developer
of a broad range of RF, microwave, and millimeter−wave test solutions and subsystems
with a focus on electromagnetic field analysis and signal processing. Withwave's
new
MEMS Switch Modules are the reflective type RF switches such as SP4T, SP10T,
4−port matrix switch according to switching applications and frequency range. They
deliver 25 W power handling, low insertion loss and high linearity, making
this devices ideal for RF signal routing in wireless infrastructure and applications
from DC to 20 GHz. External Connectors included 2.92 mm vertical launch
connectors for all RF port. They are powered and controlled through USB type−C connector...
 Unlike those IQ (intelligence quotient)
tests conceived of and administered by Ph.D. college professors with pulsating veins
in their foreheads, this "Electronics
IQ Quiz," created by Popular Electronics magazine quizmaster Robert
Balin, is a true measure of your real-world acumen. Here are a couple hints to assist
quiz takers not familiar with last century electronics. You need to have knowledge
of the NTSC-mandated broadcast television channel bandwidth for figure A, but you
might be able to guess it by process of elimination. For figure E, consider the
bandwidth limits in terms of dB, not MHz. Kinks in the characteristic curves of
the tube alluded to in figure D betray its number (extra hint: it's not a diode
or a triode). Good luck!
 "Asymmetric
Surface Plasmon Polariton Defected Ground Structure with Triple-Band Rejection and
its Application in a Gysel Power Divider with Harmonic Suppression" With a title
like that, I feel like I already know everything there is to know. If it had been
in the April issue of Microwave Journal magazine rather than in the June
issue, I'd suspect it was a Fool's errand. It could have been written by a relative
of Mohammed Ulysses Fips, who penned many articles like "Radium−Radio
Receiver "for Radio−Craft magazine. Seriously, though, kudos for authors
Jun-Bao Du, Lin Li and Xian-Chuang Su, of Zhejiang Sci-Tech University, Hangzhou,
China, for coming up with that.
 Feedback circuits seem simple enough intuitively,
at least for simple systems. It is easy, though, for someone not comfortable with
algebraic manipulations to arrive at the wrong conclusion for how a given
feedback constant figures into the calculation. Such was the case with an article
published in the July 1937 issue of ARRL's QST magazine, when many readers
wrote to the author accusing him of making an erroneous claim in an earlier article
(April) regarding using feedback to cancel out an unwanted harmonic in an amplifier.
The criticism turned out being justified. Here is a statement of the error and an
explanation of the proper approach which was printed a couple months later...
/jobs.htm"> RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable /jobs.htm">job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
quality visitors...
 Centric RF is a company offering from stock
various RF and
Microwave coaxial components, including attenuators, adapters, cable assemblies,
terminations, power dividers, and more. We believe in offering high performance
parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power
levels from 0.5-500 watts are available off the shelf. We have >500,000 RF and
Microwave passive components we can ship you today! We offer Quality Precision Parts,
Competitive Pricing, Easy Shopping, Fast Delivery. We're happy to provide custom
parts, such as custom cables and adapters, to fit your needs. Centric RF is currently
seeking distributors, so please contact us if interested. Visit Centric RF today.
Thursday the 29th
 These three
electronics-themed comics appeared in the August 1963 issue of Radio−Electronics
magazine. The subjects are things at the forefront of most peoples' minds in the
day, but are either completely unknown to the current generation and long-forgotten
by nearly everyone else. It's only people like me (and maybe you) who like to wax
nostalgic about life during what we perceive as a simpler existence with less social
craziness and greater personal freedoms. The comic on page 46 is pretty clever,
but it could just be that the artist was inspired by the concept of a horizontally
polarized magnetic loop - or a simple wire loop - antenna. Electronic kit building
(p96) was a big thing with hobbyists both because of the satisfaction that results
when your efforts are rewarded with a functioning radio or TV or multimeter or other
such device, and because at the time it was often less expensive than purchasing
a factory-built model. Kits often contained higher quality components than what
came in ready-to-use equivalents, so they lasted longer, and if they did fail, your
familiarity with the construction and operation made them easier to align and/or
repair. To understand the page 99 comic, you'd have to have battled with trying
to stabilize the picture...
 "As wireless solutions become ubiquitous,
the need for advanced RF infrastructures and systems becomes more pressing. The
growth of advanced portable devices to address the needs of business, industry,
and society in data-intensive applications is pushing demand for wider bandwidths
and more rapid processing and analysis of data in wireless systems, especially at
the network edge. Designers today need to accelerate design cycles and bring products
to market faster and more cost-effectively, while future-proofing their product
designs. To address this demand, Analog Devices launched the Apollo MxFE, an advanced
software-defined, direct RF-sampling,
wideband mixed-signal front-end platform. The solution enables higher-speed
data conversion and processing capabilities, while reducing electronic testing complexity.
Apollo MxFE helps empower next-generation applications like phased-array radar..."
 QST, the monthly publication of
the American Radio Relay League (ARRL), occasionally ran a
crossword puzzle with an electronics theme. This one by by S.M. Dunnam, Jr.
(K5KEI) appeared in the April 1967 edition. Unlike the weekly RF Cafe crossword
puzzles, this one does have a few words that are not strictly technology and science
themed. However, many of the clues and words require some familiarity with Ham radio
subjects and lingo. Enjoy!
 Werbel Microwave presents an impressive
array of features in our latest offering. With a wide frequency range spanning from
2 to 8 GHz, the C-0208-10 directional coupler ensures versatility across
various applications. Enjoy exceptional coupling flatness, with a typical ±0.2 dB
flatness that guarantees precise performance. Experience remarkable directivity,
reaching 27 dB up to 8 GHz, providing enhanced signal isolation. Benefit
from excellent return loss, reaching 28 dB up to 8 GHz, ensuring optimal
signal reflection. Additionally, our product allows for DC current to pass through
from input to output, adding to its versatility. From mobile to fixed satellite
applications, as well as lab use, WiFi, and radar, our solution meets the demands
of diverse industries...
 Although written in 1933 (era of the Great
Depression), this QST magazine article on the
autodyne
receiver has a good discussion of noise sources and how to trade off amplification
for signal intelligibility. It originally used the De Forest Audion vacuum
tube amplifier. Noise figure and noise temperature were not commonly used at the
time, but the concept is encompassed in the treatment. So, what is an autodyne?
It is a form of regenerative circuit that, rather than being tuned right at the
signal of interest, is tuned slightly off center. It functions as a sort of combined
local oscillator and amplifier for demodulating CW (Morse code) signals. Technical
writing styles have not changed much over the decades, even as the terminology has...
 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.
The file format is XML so everything plays nicely with Visio 2013 and later...
 ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies for
amplitude and phased matched VNA applications as well as standard & precision
RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the
iBwave component library. They also provide custom coax solutions for applications
where some standard just won't do. A partnership with Newark assures fast, reliable
access. Please visit ConductRF today to see how they can help your project!
Wednesday the 28t
 Usually when posting one of the Popular
Electronics magazine quizzes that includes vacuum tubes, I suggest the reader
mentally replace them with an enhancement mode FET. That is because like the tube,
all configurations of FETs have a very high input impedance, which is why vacuum
tube voltmeters (VTVMs) were used when it was important to not let the meter load
down the circuit under test. Bipolar junction transistors (BJTs), by comparison,
have relatively low input impedance, but are still useful as input buffers to mechanical
meter movements. In 1967 when this article appeared in Radio-Electronics
magazine, the MOSFET - or MOS FET as written at the time - was relatively new to
the marketplace. A single 2N3608, made by the Microelectronics Division of Philco-Ford,
cost $8.05 in 1967, which is equivalent to $72.65 as of this writing (per the BLS
Inflation Calculator). Vacuum tubes were $1 to $2 apiece...
 Modelithics is pleased to announce the release
of version 23.2 of the
Modelithics COMPLETE Library™ for Sonnet Suites. This new release adds 45 new
models and is compatible with the latest version of Sonnet (v18.56). With this release,
the Modelithics COMPLETE Library for Sonnet Suites now represents highly-accurate
models for over 26,000 components. The addition of Modelithics COMPLETE Library
models to Sonnet allows designers to combine the accuracy of full-wave analysis
of arbitrary interconnect structures with accurate equivalent circuit models for
active devices and lumped element components that scale variously with substrate,
temperature and bias conditions. With the release of version 23.2, the Modelithics
COMPLETE Library for Sonnet Suites now includes Modelithics extensive collection
of Microwave Global Models™ for capacitor, inductor, and resistor part series. The
library also includes models for other components like attenuators, splitters, and
couplers. Version 23.2 adds to the library new models for components from vendors
such as AMOTECH, Coilcraft, Kemet, Kyocera-AVX, Smiths Interconnect, Vishay, and
others. Among the new additions...
 Being that we are entering the forest fire
season with the onset of summer, this story from a 1932 edition of Radio News
magazine is an appropriate recognition of the sacrifice offered by firefighters
who battle the destructive conflagrations. Firefighters of all specialties have
relied on radio communications nearly since its inception, and particularly once
battery-powered versions became available for portability. It is hard to imagine
a time when such a convenience - even a necessity - was not part of the standard
firefighting outfit. Nowadays the radios are compact and clip onto a shoulder lapel,
but in 1932 the vacuum tubes, large transformers and batteries meant even a primitive
radio was in the form of a
harness-mounted manpack radio (a word not yet coined at the time). The portable
half-wave dipole antenna in the picture looks almost exactly like ones I have seen
advertised in contemporary issues of QST magazine...
 "DigiKey,
a leading global commerce distributor offering the largest selection of technical
components and automation products in stock for immediate shipment, has partnered
with GroupGets to launch the 'Get
MADE' crowdfunding initiative, a collaboration that promotes and funds hardware
creators. This program will allow startups to get hardware funded, produced and
sold on DigiKey's website. Image of DigiKey Partners with GroupGets to Enable Hardware
Startups to Bring Products to Market DigiKey and GroupGets will launch a crowdfunding
program to promote and fund hardware creators. GroupGets is a crowd purchasing platform
for group buying technology products that helps businesses and individuals launch
their products by promoting, funding and distributing electronic devices across
the world. Through the 'Get Made' program, GroupGets and DigiKey will cross promote
qualifying devices through content, design, distribution and partial funding through
DigiKey. Upon successful funding, GroupGets will work with the creators to manufacture
the platforms and then DigiKey will list the platforms for sale on its website..."
 Electron-coupled oscillators (ECOs) were
a real breakthrough in achieving frequency stability in harsh environments that
included mechanical vibration, temperature excursions, power supply variations,
and load changes. Use of vacuum tubes made the task even more challenging. Such
oscillators were necessarily very expensive compared to less sophisticated designs.
Henry E. Rice Jr., W9YZH, introduced his "Rice Variarm" model (aka the Millen Model
90700) at a breakthrough price of just $29.50, which in 2023 money equates to $635
per the U.S. BLS Inflation Calculator. That is a lot of moola for amateur radio
operators even today. The arm sticking out of the case is for adjusting the frequency
- hence, the Variarm...
 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 or
so 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. Check them out!
 Copper Mountain Technologies develops innovative
and robust RF test and measurement solutions for engineers all over the world. Copper
Mountain's extensive line of unique form factor
Vector
Network Analyzers include an RF measurement module and a software application
which runs on any Windows PC, laptop or tablet, connecting to the measurement hardware
via USB interface. The result is a lower cost, faster, more effective test process
that fits into the modern workspace in lab, production, field and secure testing
environments. 50 Ω and 75 Ω models are available, along with
a full line of precision calibration and connector adaptors.
Tuesday the 27th
The
Better Business Bureau (BBB) was founded in 1912 as the National Vigilance Committee
for the Promotion of Ethical Business Practices in Advertising. It was later renamed
the Better Business Bureau in 1921. The organization was established in response
to concerns about fraudulent and deceptive advertising practices, with the goal
of improving consumer trust in the marketplace. In the early years, the BBB primarily
focused on combating misleading advertising. It worked to establish standards for
truthful advertising and to expose businesses that engaged in deceptive practices.
One of the key features of the BBB is its accreditation program. The BBB also assigns
ratings to businesses based on various factors, including complaint history, transparency,
and customer reviews. Less than an A+ rating was to be avoided, especially by larger
companies, so having a major publication like Radio−Electronics magazine
shine light on the situation no doubt motivated them into corrective action mode...
 Axiom Test Equipment allows you to
rent or
buy test equipment,
repair
test equipment, or sell or trade test equipment. They are committed to providing
superior customer service and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today - and don't miss the blog articles!
 In the early 1930s, QST magazine
(ARRL's monthly publication) usually ran a line at the bottom of every page in the
back half of each issue that said, "Say You Saw
It in QST - It Identifies You and Helps QST." They even got the capitalization
correct (all lower case short prepositions and conjunctions, but I digress). The
December 1933 edition was a bit different, however, in that all the left-hand pages
had the message translated into one of fourteen different languages while the right-hand
pages used English. I deemed that discovery cool enough to scan and post here. Since
the only languages I speak with any fluency are English and Pig Latin, I took the
trouble of entering the English sentences into the Google Translator engine for
each language and posting what it says is the correct translation, at least by 2023
standards. If any of the languages are your native tongue and you would be kind
enough to provide me with the "real" translation, I would be mighty grateful and
would add that (along with credit to you) to the page...
 "Teamwork makes the dream work, and at NASA
that doesn't apply only to humans. Researchers at NASA's Ames Research Center in
California's Silicon Valley are developing
satellite swarms, which are groups of spacecraft working together as a unit,
without being managed individually by mission controllers. A swarm's ability to
perform autonomously will make new types of science and exploration possible, particularly
as they venture farther into deep space. Ames' work on swarm technologies has been
underway for decades. This summer, swarm science will reach a major milestone as
NASA launches the Starling mission into space. It will test technologies that let
four spacecraft operate in a coordinated manner without resources from the ground.
And the results of Starling's experiments will be of great interest to researchers
at Ames who..."
 This Radio & TV News magazine
article on crystal filters will probably be more useful to people responsible for
maintenance on old RF systems than for new designs. The technology has come a long
way since 1957 when it was published.
Crystal filters were heralded as godsends as airwaves became more crowded and
simple LC filters could not provide the required Q to prevent cross-channel interference.
Of course the problem is many times worse today, but components are better now than
then with low-cost integrated circuit front ends that handle a lot of the selectivity
issues and SAW filters with better performance than many crystals...
 We live in an era where the actions of people
and civilizations of distant history are held accountable to contemporary standards.
The term is "presentism."
If the original perpetrator of the judged sin cannot be punished, then impose a
penalty on the descendants, be they people or governments. At the forefront of presentism
is slavery. No moral person condones slavery. No living person owns or has owned
slaves (well, maybe in Somalia and a few other places we must never mention). Oh,
and then there's the current human trafficking organizations around the world, and
near-slave workers mining raw materials for and building our tech devices, but I'm
not addressing them, either. Reuters just published a piece entitled, "America's
Family Secret," that reveals more than 100 U.S. leaders - lawmakers, presidents,
governors and justices - who are direct descendants of slaveholders. All appear
to be White men and women, except for one Black man. Notably absent are any Orange
men.
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 2018 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. An intro video takes you through the main features...
 Providing full solution service is our motto,
not just selling goods. RF & Connector Technology has persistently pursued a management
policy stressing quality assurance system and technological advancement. From your
very first contact, you will be supported by competent RF specialists; all of them
have several years of field experience in this industry allowing them to suggest
a fundamental solution and troubleshooting approach. Coaxial RF connectors, cable
assemblies, antennas, terminations, attenuators, couplers, dividers, and more. Practically,
we put priority on process inspection at each step of workflow as well as during
final inspection in order to actualize "Zero Defects."
Monday the 26th
 What a difference a punctuation mark can
make, in this case a hyphen. If this 1961 Radio-Electronics magazine article had
been titled "Anti-Plane Collision Radar" rather than "Anti-Plane-Collision
Radar," the theme might seem to address a radar system biased against airplanes
and desiring to promote collisions amongst them, rather than wanting a radar system
designed to prevent collisions. In making his point, editor Hugo Gernsback uses
as an example a recent (at the time) 1960 mid-air collision between a Douglas DC−8
(4-engine jet) and a Lockheed Super Constellation (4-engine propeller) which occurred
over New York City. Another cited was a 1956 mid-air over the Grand Canyon, which
also involved a Super Constellation and this time a Douglas DC-7 (4-engine propeller).
Airborne collision avoidance systems (ACAS) have been incorporated into airborne
radars for many decades, which act independently of ground-based collision avoidance
systems. Mr. Gernsback's call...
 "Under certain conditions—usually exceedingly
cold ones—some materials shift their structure to unlock new, superconducting behavior.
This structural shift is known as a
'nematic
transition,' and physicists suspect that it offers a new way to drive materials
into a superconducting state where electrons can flow entirely friction-free. But
what exactly drives this transition in the first place? The answer could help scientists
improve existing superconductors and discover new ones. Now, MIT physicists have
identified the key to how one class of superconductors undergoes a nematic transition,
and it's in surprising contrast to what many scientists had assumed. The physicists
made their discovery studying iron selenide (FeSe), a two-dimensional material that
is the highest-temperature iron-based superconductor. The material is known to switch
to a superconducting state at temperatures as high as 70 kelvins..."
 In the days before space-based radio astronomy,
observations on many frequencies required waiting until nightfall because the Earth's
ionospheric activity interfered with signals in many bands of interest. Two such
bands are 18 MHz and 20 MHz (16 and 15 meters, respectively), on which
information on lightning-type discharges from Jupiter are received. Near-real-time
maps of ionospheric absorption in the D layer (caused by solar x-ray activity) are
available on the Solar Terrestrial Dispatch website for 5 through 30 MHz, which
is where long-range high frequency (HF) communications occur. The F2 layer is where
signals are usually reflected, but absorption in the lower D layer can be severe
enough to limit reception. This "Radio
Signals from Jupiter Studied by N.B.S." story from the August 1957 issue of
Radio & TV News magazine presents the state of the science at the time...
 Television development was a distant memory
for most people during the dark days of World War II. Germany's forces launched
its second siege of the 20th century against Europe in Fall of 1939. By January
of 1945, even the Brits were beginning to feel confident that the seemingly endless
days of World War II were about to come to an end. Hitler's forces had been
beaten back from its massive sprawl across Europe and into northern Africa. Eisenhower's
D-Day campaign six months earlier had broken the back - and much of the will - of
German forces. The Battle of Leyte Gulf shortly thereafter severely damaged Japanese
naval forces. Slowly but surely improvements were made in TV camera, broadcast,
and local viewing technology in spite of the severe restrictions placed on component
and manpower availability, both in the UK and in the U.S.
John Logie Baird was England's most famous television pioneer...
 Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 website 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 728x90-px
and 160x600-px 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...
ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies for
amplitude and phased matched VNA applications as well as standard & precision
RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the
iBwave component library. They also provide custom coax solutions for applications
where some standard just won't do. A partnership with Newark assures fast, reliable
access. Please visit ConductRF today to see how they can help your project!
Sunday the 25th
 "A democracy cannot exist as a permanent
form of government. It can only exist until the voters discover that they can vote
themselves largesse from the public treasury [we're past
this point]. From that moment on, the majority always votes for the candidates
promising the most benefits from the public treasury with the result that a democracy
always collapses over loose fiscal policy, always followed by a dictatorship. The
average age of the world's greatest civilizations has been 200 years. These nations
have progressed through this sequence: From bondage to spiritual faith; From spiritual
faith to great courage; From courage to liberty; From liberty to abundance; From
abundance to selfishness; From selfishness to apathy; From apathy to dependence;
From dependence back into bondage."”--
Alexander Fraser Tytler
 This custom RF Cafe
electronics-themed crossword puzzle for June 25th contains words and clues which
pertain exclusively to the subjects of electronics, science, physics, mechanics,
engineering, power distribution, astronomy, chemistry, etc. If you do see names
of people or places, they are intimately related to the aforementioned areas of
study. Being that "B" is the 2nd letter (25 mod 23) of the alphabet, it is used
as the first and/or last letter (or even in-between) of many words in today's crossword
puzzle. Those clues are marked with an asterisk (*). As always, you will find no
references to numbnut movie stars or fashion designers. Need more crossword RF Cafe
puzzles? A list at the bottom of the page links to hundreds of them dating back
to the year 2000. Enjoy.
/jobs.htm">RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable /jobs.htm">job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
quality visitors...
 Please take a few moments to visit the
everythingRF website to see how they can assist
you with your project. everythingRF is a product discovery platform for RF and microwave
products and services. They currently have 267,269 products from more than 1397
companies across 314 categories in their database and enable engineers to search
for them using their customized parametric search tool.
Friday the 23rd
 For a couple years in the 1963 era,
Radio−Electronics magazine ran a monthly feature called "What's
Your EQ?," where EQ stood for Electronics Quotient. It was a play on IQ - Intelligence
Quotient. Some the problems posed are real posers, but most are within the capability
of RF Cafe visitors - even the ones showing vacuum tubes since you can usually mentally
replace them with transistors and solid state diodes. "L-Pad Puzzler" is a fairly
simple circuit analysis equation. Be sure to approach it from terminals 3 and 4.
The solution given for "Fussy Fuses" is questionable the way I look at it. It seems
to me if the five branches have no resistance (or even exactly the same resistance),
the current would split equally amongst them, so as current is increased the 1A
would blow, then the 2A, up through the 5A, then that would be it. R−E concluded
differently. "Voltage Divider" is a little more of a challenge...
 Chile's Atacama Desert is getting a lot
of news play these days due to some "extremely large" manmade features being created
there. Some are good things, and some not so much. Examples of good things are the
Very Large Telescope and the Extremely Large Telescope
(ELT), the latter being constructed by the European Southern Observatory, is the
world's largest and most advanced Earth-based telescope. Its location atop Chile's
Cerro Armazones mountain is at an altitude of 9,993 ft (3,046m) in the
central part of Chile's Atacama Desert. At 39 m in diameter, it will collect
15x more light than the next largest. It will record many petabytes of data each
year while performing entire sky surveys in multiple wavelengths. AI is being developed
to assimilate it all because there aren't enough humans available. Another extremely
large object being built in the Atacama Desert is a
giant pile of brand new, discorded clothing (Google
image), about 300 miles north of the ELT. Unsold clothes containing huge
amounts of petroleum product components (nylon,
polyester, acrylic) will take centuries to decompose. Petroleum-burning cargo
ships sail the seven seas to deliver them, thence diesel trucks and excavation equipment
dispose of them. Many people will whine about spending money on space science
while turning a blind eye to incredible waste and pollution. Hypocrites.
 "Art Combines with Precision Engineering,"
proclaims the
Scott Transformer Company advertisement that appeared in a 1930 edition of
Radio News magazine. I'm not sure how many radios Scott sold, but a fairly
extensive Google and eBay searches turned up only one restored model of the fancy
"artistic" cabinet type. Based on the prices in the ad, most people probably could
not afford to buy them. According to the BLS* Inflation Calculator, the $703 "Cortez"
radio would cost $12,555 in 2023 money. Even the $334 "Cavalier" at an equivalent
of $5965 would cost more than many houses in 1930! Black Tuesday had precipitated
just a few months prior to this March edition, so all the design and manufacturing
accommodations had already been put in place. Plus, publishing lead times were many
months in advance so this promotion likely was arranged and paid for before the
Stock Market crash in October of 1929. "No station tunes at more than one point
on the dial and local stations do not interfere, even to the slightest degree, with
distant reception. Four Screen Grid tubes are used in this new Scott Model. Think
of it! Four Screen Grid tubes!" Evidently affordable, crappy reception was good
enough for the times...
 Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his May 2023 newsletter that features
his short op−ed entitled "Filters
Save the Day." In it, Sam discusses how two of the biggest issues of the day
concerning RF interference - the coexistence of C-band cellphone service and radar
altimeters, and AM radio in electric vehicles - are relatively easily solved with
filters. I have posted links to many news stories covering both challenges in the
last few years. Sam makes a good point about the AM radio in EV's, that being whereas
car manufacturers say the noise generated by the propulsion systems (brushless motors
which run on high frequency pulses) will wreak havoc with AM radio, there will certainly
be other susceptibilities needing to be dealt with by onboard systems. I will add
that dense urban environments filled with EMI-spewing EV's might also cause serious
problems for external systems as the ambient noise floor rises ever higher...
 TrueTone was the brand name for electronic
equipment sold through Western Auto (Supply Company). Western Auto started business
in 1909 and died, sadly, in 2003. Other well-known companies had branded electronics
as well; e.g., Sears had Silverline and Montgomery Ward had Airline.
TrueTone models D1747 and D1748 were cabinet-style combination radio receiver
and phonograph. This schematic and parts list set from a 1947 issue of Radio News
magazine did not include any service data, as was provided for most radios published.
There are still many people who restore and service these vintage radios, and often
it can be difficult or impossible to find schematics and/or tuning information.
A running list of all data sheets is shown at the bottom of the page to facilitate
a search...
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.
The file format is XML so everything plays nicely with Visio 2013 and later...
 Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
procedures.
Thursday the 22nd
 "News Briefs" in the March 1960 issue of
Radio-Electronics magazine contained many very interesting developments
related to research and development in communications. Headlines included among
other things
Tropospheric Telephone Spans Atlantic, TV, Radio Astronomy Struggle for Channel
37, Needle Belt Orbits, Laser Transmits 118 Miles, Diplomat's Dog Is Howling Counterspy,
and, Short-Wave Listeners Hear Ham Gossip, Space News. A decade has passed since
the International Geophysical Year (IGY) results had come in and much work in tropospheric
and ionospheric signal scatter, absorption, and reflection was in process. An intense
battle between the Communist world and the free world for technology dominance was
a major factor in the process. The Space Race was in full gear, with Apollo 11
scheduled to land the first men on the moon within a few months. Reliable communications
between Earth...
 "The trend toward society's 'smart-electrification'
is driving the need for ESD immunity at the system-level. IEC 61000‑4‑2 [1] defines
how to perform the electrostatic discharge immunity test at the system level. Until
about 15 years ago, protecting against such events involved implementing
ad-hoc ESD protections (TVS) at board/system-level in proximity to the connectors
interfacing with the 'external world.' However, a new trend of implementing system-level
robustness at the component level (i.e., on-chip) is quickly becoming standard practice,
mainly stemming from the desire to reduce system/board design costs. While this
may sound like a logical step on paper, it poses enormous challenges to the component
ESD designer in that: IEC 61000-4-2 is not applicable at the component level, so
every company is struggling to understand / design proprietary characterization
methods at the component level to extrapolate performance at system-level..."
 Philco began selling radios in 1928 after
originally being a storage battery manufacturer. Their first television, the Predicta,
was introduced in 1957. That was more than a decade after Philco Corporation's James
Carmine wrote this article discussing how the American buying public might embrace
the concept of TVs in their homes. Many people at the time had
no interest in television both due to the expected cost and the relatively poor
performance of existing examples. If you have ever seen pictures of early TVs, they
typically had very small displays and poor picture quality (obvious scan lines,
low contrast, picture distortion, etc.). As with almost all forms of consumer electronics,
production and sales of new television sets was put off during World War II
so that precious components and materials would be available for the war effort.
Once the war ended in 1945, all industries were unleashed and a flood of surplus
items, from electronics to mechanics to clothing, hit the distribution markets providing
virtually limitless access to designers and resale distributors at prices far below
retail...
 Are you old enough to remember the
mosquito spray trucks running through your neighborhood during the summer? Whilst
a child living in
Mayo, Maryland, in the 1960s, I vividly remember trucks similar to this one
going by our house with a big fan on the back blowing what was almost certainly
DDT with such force that it shook
the trees. We would hurry to shut all the windows if lucky enough to hear the truck
coming. That stuff stunk. Mayo is a peninsula off the Chesapeake Bay, and it was
a breeding ground for skeeters. If you went outside in the evening after a rain
on a hot, humid day, you would get eaten alive - so to speak. A can of "Off Insect
Repellant" sat on our back door stoop all summer long. Remember the
"Off" commercial? Mosquitoes
don't bite; they don't even light." Boy, am I getting old! According to the hype,
all of my friends and I should be dead by now.
 RIGOL Technologies is transforming the Test
and Measurement Industry. Our premium line of products includes digital and mixed
signal oscilloscopes, spectrum analyzers, function / arbitrary waveform generators,
programmable power supplies and loads, digital multimeters, data acquisition systems,
and application software. Our test solutions combine uncompromised product performance,
quality, and advanced product features; all delivered at extremely attractive price
points. This combination provides our customers with unprecedented value for their
investment, reduces their overall cost of test, and helps speed time to completion
of their designs or projects.
 Although the application is a bit outdated,
the lesson presented in this 1934 Radio News and Short−Wave magazine article
about
taming the chirps and thumps of keying Morse code via pulse shaping techniques
is still useful today. While fully tamed (aka compensated / damped) commercial keys
and keying circuits are available that require no technical knowledge of how they
work or how to fine tune their operation, there are still many more older units
operating that might need some tweaking. This is part 3 of a multi-issue article,
so the few references to nonexistent illustrations are not typos. Figure 1
is reproduced from Part 1 of the article, and then the series picks up with
Figure 7. Unfortunately, I have not yet acquired those previous two issues...
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 or
so 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. Check them out!
 The
Wireless Telecom Group,
comprised of Boonton, Holzworth, and Noisecom, is a global designer and manufacturer
of advanced RF and microwave components, modules, systems, and instruments. Serving
the wireless, telecommunication, satellite, military, aerospace, semiconductor and
medical industries, Wireless Telecom Group products enable innovation across a wide
range of traditional and emerging wireless technologies. A unique set of high-performance
products including peak power meters, signal generators, phase noise analyzers,
signal processing modules, 5G and LTE PHY/stack software, noise sources, and programmable
noise generators.
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
Homepage Archive Pages
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan | Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2014:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012:
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 (no archives before 2012)
|
