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4 of the October 2022 homepage archives. Monday the 31st
 This "The Hand of Selene"
Carl and Jerry adventure appeared in the November 1960 issue of Popular
Electronics just in time for Halloween. The magazine would have arrived in
mailboxes on newsstands sometime in October. With the great popularity of zombies
and the undead these days (in which I personally have zero interest), the scheme
outlined here to make the hand of Selene (an Egyptian moon goddess) tap out answers
to a soothsayer's questions would be a great scheme to use at a Halloween party.
Read on to discover the tech savvy teenagers' clever implementation...
 Just keep repeating, "There is no inflation.
We are not in a recession." The Bloomberg report on Halloween candy cost increases
this year surely must be wrong, but I reposted some of them here anyway (see thumbnail).
I've dubbed it "Candyflation."
Reese's candy is up 35% over a year ago. Twix is up 53%. That's nothing; I just
paid $118 for a roll of 14-2 Romex wire that cost about $40-$45 two years ago. Gasoline's
gone from $2.10/gallon to north of $4/gallon, depending on where you live. Electricity
rates here have gone up >10% in two years and
Duke Energy wants another 14% or more. Don't blame it on insane levels of deficit
spending the last couple years, though. It can't be infrastructure costs and supply
shortages needed to accommodate
>5M
illegal aliens crossing our southern border in the last two years. Of course not.
It's that darn Putin causing all the problems, don't you know! We're being devastated
here at RF Cafe.
 How often have we all mistaken "spooks"
for
Barkhausen oscillations? Yeah, it's embarrassing, but we've all done it. I can't
tell you how many times as a kid I saw the tell-tale effects on our old black and
white TV and said, "Mom, can you remind Dad to do something about those dang Barkhausen
oscillations when he gets home from the newspaper office?" If you believe that line
of bull hockey, I've got some waterfront property in the Sahara Desert to sell you.
The only thing close to "Barkhausen" I might have known back then was the name of
a German beer house on Hogan's Heroes (for which I own the entire DVD set). Anyway,
this article, written in the days of over-the-air television broadcasts, presents
a solution to the annoying "spook" effect caused by poor oscillator circuit shielding...
 TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms
are available to provide temperatures between -100°C and +200°C for cryogenic cooling,
recirculating circulating coolers, temperature chambers and temperature controllers,
thermal range safety controllers, space simulation chambers, hybrid benchtop chambers,
custom systems and platforms. Manual and automated configurations for laboratory
and production environments. Please contact TotalTemp Technologies today to learn
how they can help your project.
 Haunting the renewable energy extremists
this Halloween is the reality of a need for cheap, reliable electricity. The "renewable"
adjective is a farce since once a form of energy is converted to another form it
cannot be used again - unless you have a >100%
Sterling machine. It
is a feel-good term for activists. Faced with a freezing citizenry this winter,
we learn: "A wind farm in Germany is being dismantled to
expand the Garzweiler lignite mine. One of eight turbines installed at the location
in 2001 has already been removed. Nevertheless, the German state of North Rhine-Westphalia
said it would phase out coal by 2030, as did RWE, the company that owns the mine."
Ach du lieber!
 Just in time for Halloween, John T. Frye's
teenage sleuths
Carl & Jerry unexpectedly recorded a late-night conversation between two
men where they plot how to dispose of the "body" when death occurred as a result
of prolonged choking. Employing their trademark technical prowess and scheming ability,
the pair sets a trap for the perpetrators and dutifully summon the authorities as
they complete their nefarious act of the night before. Halloween comes into play
because the recordings were made for use in creating sound effects during the reading
of Edgar Allen Poe's "The Pit and the Pendulum" and "The Cask of Amontillado." This
story, which appeared in a 1955 issue of Popular Electronics magazine, is a little
dark compared to a typical Carl & Jerry story...
 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 (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1
scale so that measurements can be made directly using Visio built-in dimensioning
objects. Page templates are provided with a preset scale (changeable) for a good
presentation that can incorporate all provided symbols...
 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.
Sunday the 30th
 Here is your custom made
Vintage Radio Themed crossword puzzle for October 30th, 2022. Relevant clues
have an asterisk (*) by them. All RF Cafe crossword puzzles are custom made by me,
Kirt Blattenberger, and have only words and clues related to RF, microwave, and
mm-wave engineering, optics, mathematics, chemistry, physics, and other technical
subjects. As always, this crossword contains no names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort unless it/he/she is
related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska
event in Siberia). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!
 Triad RF Systems designs and manufactures
RF power amplifiers
and systems. Triad RF Systems comprises three partners (hence "Triad") with
over 40 years of accumulated knowledge of what is required to design, manufacture,
market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA,
bi-directional, and frequency translating amplifiers are available, in formats including
tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology
partner than a vendor for our line-of-sight communications product line." Please
check to see how they can help your project.
Friday the 28th
 Every hobby magazine worth the paper its
printed on has a "tricks
of the trade" type column. Popular Electronics started out its very
first issue in October 1954 with a column that went by exactly that name. It contained
a very extensive assortment of tips and tricks (aka "kinks"). The images are rather
small, but you can get what the inventor had in mind. It's good stuff to know, even
in 67 years later in 2022 because just about everything here is applicable in today's
electronic projects...
 You might need to be an antenna aficionado
to score well on this
Antenna Quiz which appeared in the November 1962 issue of Electronics World
magazine. While the antenna configurations are familiar in most cases (after reading
the answers' descriptions), some of the names are not (at least not to me). Links
to a couple of the ones I wasn't aware of are provided for your benefit. Whenever
I see the Beverage antenna mentioned I always envision one of the homebrews (pun
intended) when someone soldered together a stack of beer or soda cans to create
a ¼-wave vertical or some similar configuration. Of course it was named after the
inventor, Harold Beverage. The Zeppelin antenna mentioned here is often referred
to as a Zepp. It got its name from the antenna configuration often used on the Zeppelin
airships, including on the Hindenburg. Contrary to the belief by some people...
 "A recent discovery by materials science
researchers in Drexel University's College of Engineering might one day prevent
electronic devices and components from going haywire when they're too close to one
another. A special coating that they developed, using a type of two-dimensional
material called MXene, has shown to be capable of
absorbing and disbursing the electromagnetic fields that are the source of the
problem. Buzzing, feedback or static are the noticeable manifestations of electromagnetic
interference, a collision of the electromagnetic fields generated by electronics
devices. Aside from the sounds, this phenomenon can also diminish the performance
of the devices and lead to overheating and malfunctions if left unchecked. While
researchers and technologists have progressively reduced this problem with each
generation of devices, their strategy thus far has been to encase vital components..."
 Any mention of a "Zeppelin" conjures up
thoughts of disaster in the form of the famous Hindenburg incident at Lakehurst,
New Jersey, back in 1937. Fortunately, not all things "Zepp" are bad news. The
end-fed Zepp (short for Zeppelin) antenna is as popular today as it was when
the Germans developed it for use in the Zeppelin airships. One of the major advantages
to an end-fed Zepp is that it is, as the name suggests, fed from the end rather
than in the center like a dipole. The configuration makes installation simpler than
a dipole. Being so simple in construction, the Zepp handily functions as a multi-band
harmonic antenna so it is useful on, for instance, the 160, 80, 40, 20, and 10 meter
Ham bands. Many companies (e.g., MFJ Enterprises) sell Zepp antennas as well as
the modified Zepp known as a J-pole antenna. This article will help you make your
own Zepp antenna system, including a matching network...
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...
 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. Amplifiers, test equipment,
power couplers and dividers, coaxial connectors, waveguide, antennas, filters, mixers,
power supplies, and everything else. Please visit everythingRF today to see how
they can help you.
Thursday the 27th
 Where else other than an original article
like this one from a 1945 issue of Radio News magazine are you likely to
find such detailed information on the construction of early vacuum tubes? This is
Part 21 of the "Saga
of the Tube" series. The reference list for information on various tubes is
extensive. Having always been interested in the origin of names and designations
of components of all sorts, things like learning "...the designation 'EVN' indicates
that the tube was intended for use in a receiver (E = Empfanger) as an amplifier
(V = Yerstärker ) at low frequencies (N = Niederfrequenz)" is appreciated. You will
find many articles on the history of vacuum tubes, beginning with Dr. Lee de
Forest's audion, by searching RF Cafe. I found the death notice of author Gerald
F. J. Tyne in the April 4, 1981 edition of The New York Times newspaper - headline:
"Gerald F. J. Tyne, 81, an Engineer, Researcher and Museum Director..."
 "Recent developments in AI have been astounding,
but so are the costs of
training neural networks
to do their astounding feats. The biggest, such as the language model GPT-3 and
the art generator DALL-E 2, take several months to train on a cluster of high-performance
GPUs, costing millions of dollars and taking up millions of billions of billions
of basic computations. The training capabilities of processing units have been growing
rapidly, as much as doubling in the last year. To keep the trend going, researchers
are digging down into the most basic building blocks of computation, the way computers
represent numbers. 'We got a thousand times improvement [in training performance
per chip] over the last 10 years, and a lot of it has been due to number representation,'
Bill Dally, chief scientist..."
 Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his October 2022 newsletter that
features his short op-ed entitled "It's
Getting Crowded in Low Earth Orbit," where he discusses the rapidly increasing
number of both operational and non-operational satellites in low earth orbit (LEO).
It presents both a physical space crowding problem and an RF spectrum crowding problem.
Companies like Anatech help with the RF crowding by designing and building filters
to mitigate the presence of nearby signals. Companies like ClearSpace SA (Switzerland)
are working the physical space crowding issue by designing and building grappling
bot satellites which will grab a satellite (or large debris) and drag it to a lower
orbit for atmospheric re-entry. I wonder what the carbon footprint is of a launch
vehicle needed to get the bot aloft...
 John Bardeen, of Bell Telephone Labs, announced
the
invention of the transistor 10 years to the month before this article was written
in the December 1957 issue Popular Electronics magazine. A decade later,
engineers and scientists had revolutionized electronics for commercial, military,
and hobby applications. It seems strange to read here about applying transistors
at high frequencies, where the definition of "high" is in the hundred of MHz. High
power from a transistor was measured in tens of watts. Today they operate into the
terahertz realm, and at power in the hundreds of watts. We've come a long way, baby...
 New Scheme rotates
all Banners 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 12,000 pages in the Google search index, RF Cafe returns in favorable
positions on many types of key searches, both for text and images. 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. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
 The
Wireless Telecom Group,
comprised of Boonton, CommAgility, 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.
Wednesday the 26th
 The U.S.
Telstar 1 communications satellite launched atop a Thor-Delta rocket on
July 10, 1962. It was the first satellite to relay television shows and live broadcasts,
telephone calls, and telegraph messages - all analog of course - for both domestic
and international purposes. Electronics World magazine editor W.A. Stocklin
used his editorial space in the November issue to salute the engineers and scientists
that made it possible - which includes all those who paved the way for Telstar I.
Planning and development was performed by a consortium of companies and government
agencies. Bell Telephone Laboratories built the hardware. AT&T (a spin-off of
Bell Telephone Company) actually owned Telstar I. Note that in 1962 the unit
prefix "pico" was not in common use, so it mentions micromicrowatts rather than
picowatts. Similarly, publications of the era (and before) used micromicrofarads
(μμF) rather than picofarads (pF)...
 "Researchers at the University of Tokyo
in Japan, Cornell and Johns Hopkins Universities in the U.S. and the University
of Birmingham in the UK have observed large piezomagnetism in an
antiferromagnetic material,, manganese-tin (Mn3Sn). The finding could allow
this material and others like it to be employed in next-generation computer memories.
Antiferromagnetic materials are promising candidates for future high-density memory
devices for two main reasons. The first is that electron spins (which are used as
the bits or data units) in antiferromagnets flip quickly, at frequencies in the
terahertz range. These rapid spin flips are possible because spins in antiferromagnets
tend to align antiparallel to each other, leading to strong interactions among the
spins. This contrasts with conventional ferromagnets, which have parallel electron
spins. The second reason is that while antiferromagnets have an internal magnetism
created by the spin of their electrons, they have almost no macroscopic magnetization.
This means that bits can be packed..."
 If you thought the only 1940's-60's era
vehicles still serving as mainstream transportation in Cuba were rusting hulks of
Chevys and Fords, check out this Antonov An-2 biplane just used by pilot Ruben Martinez
to escape the island paradise. This plane could have been on an airport tarmac during
the Cuban Missile Crisis.
That beautiful radial engine is similar to the ones in the Boeing B-17 Superfortress
used in WWII. Maybe Mr. Martinez should have routed his flight to cross into
the USA via Mexico, because recently some
Cuban refugees arriving via the ocean have been returned, while millions of
undocumented, unauthorized aliens are welcomed at the land border. The State Department
began allowing
travel to Cuba for certain purposes in 2017 in spite of the long-standing atrocious
human rights policies.
 If you appreciate good humor, then you'll
appreciate these electronics-themed comics from the January 1958 edition of
Radio-Electronics. Their themes are representative of situations common in
the era - like TV repairman woes and men obsessed over electronics gadgets while
ignoring their wives. Not that there are rarely ever any comics in today's electronics
magazines, but if there were, they likely would poke fun at Oblivion texters and
depict fathers being made to look like fools by their disrespectful kids for not
knowing how to program a Roku player...
 Who hasn't had some involvement with the
iconic
555 timer IC, whether by designing it into a circuit, aligning or troubleshooting
a circuit in which it is used, or simply in a classroom or self-study text? I remember
many moons ago making a windshield wiper delay circuit for a 1982 Ford Escort, and
somehow I wired it in wrong and fried the 555 - it literally blew the plastic case
away from over the die! Anywho, this article by Cabe Force Satalic Atwell from
Electronic Design does a nice job of delving into the 555 timer's origins
- including how it got its name, which I'll bet you didn't know (and neither did
I)...
 With such a good response to the posting
of articles from vintage QST magazines, I figured it would be worth investing
in some copies of other electronics-related magazines because people old and young
enjoy learning about the history of electronics.
Popular Electronics was published from October 1954 through April 1985.
I remember reading the magazine back in my USAF days (1978-1982). A couple batches
of Popular Electronics magazines came up for auction on eBay back in the middle
of 2011, and I managed to snag one set that included the December 1954 issue (Vol.
1, No. 3, which was the third edition ever printed). It also included some editions
from early 1955 and others stretched into the early 1960s. This is the first installment.
Popular Electronics was a hobbyist's magazine, and was chock full articles
on small electronics projects, Ham radio, radio-controlled aircraft equipment, audio
amplifiers, model train control, basic electronics lessons, and useful charts and
tables of data...
 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 job openings. HR department employees and/or managers of
hiring companies are welcome to submit opportunities for posting at no charge
(of course a gratuity will be graciously accepted). 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 ...
 LadyBug Technologies was founded in 2004
by two microwave engineers with a passion for quality microwave test instrumentation.
Our employees offer many years experience in the design and manufacture of the worlds
best vector network analyzers, spectrum analyzers, power meters and associated components.
The management team has additional experience in optical power testing, military
radar and a variety of programming environments including LabVIEW, VEE and other
languages often used in programmatic systems. Extensive experience in a broad spectrum
of demanding measurement applications. You can be assured that our Power Sensors
are designed, built, tested and calibrated without compromise.
Tuesday the 25th
 Lots of unfamiliar names of crystal minerals
appear in this infomercial by Bell Telephone Laboratories in a 1956 issue of
Radio-Electronics magazine. A few such as sodium chloride (aka table salt),
arsenic, cuprite, perovskite, spinel, graphite, and beryllium are fairly well known
to those of us in the electronics realm, but others like rutile, tridymite, cristobalite,
wurtzite, diamond, and niccolite are new to me. Interestingly, rutile "has one of
the highest refractive indices at visible wavelengths of any known crystal and also
exhibits a particularly large birefringence and high dispersion." I should have
known that. Cristobalite has the same composition as quartz but with a different
crystal structure. Niccolite, and a couple others contain arsenic. Why are Bell
Labs scientists concerned with these and other compounds? By investigating and learning
the properties of a wide variety of materials, examples useful to the improvement
of their telecommunications infrastructure and end user devices were be discovered.
Equally importantly...
 If you, like me, appreciate the sheer engineering
genius and artistry of a vacuum tube - especially the special purpose types - then
you'll want to peruse the extensive collection of Mr. Robert Gillespie. His
vacuum
tube gallery is hosted on the RadioMuseum.org website. He writes: "I started
collecting tubes when I was 10, they were like little pieces of artwork. My fascination
with tubes took off when I found my first industrial tube in an old warehouse. I
do enjoy the odd photocells and photomultipliers, anything built by hand and not
by machine. Currently, my focus is on collecting anything pre-1925 from anywhere
in the world - which has been greatly boosted as I am now the curator of the Gerald
Tyne Collection, author of 'Saga of the Vacuum Tube,' 1977." If you have a unique
vacuum tube not already represented there, you are welcome to submit photos and
information. There are 1,629 as of this writing.
 The last time I used
300 Ω twin-lead transmission cable for a television antenna is about 20
years ago when I lived in a fairly rural area and had a VHF/UHF aerial mounted on
a 20-foot tower with a rotator. Since then the connections have always been 75 Ω
coax either to wired cable or a satellite dish (now I have neither). I do, however
still have 300 Ω twin-lead running from my ½-wave dipole antenna that is used
for FM radio reception. Most people more than 40 years old remember seeing the old
twin lead running down across the house roof, down the side, and through the living
room wall. My guess is that little consideration was given to cable routing and
how it might affect the performance of the cable. Twin-lead cable is amazingly low
loss - typically much lower than coaxial cable - when properly suspended. Its weakness
is its vulnerability having its impedance altered by nearby structures. Coaxial
cable largely solves the proximity problem because in an ideal coaxial cable, all
the RF current flows on the outer surface of the center conductor and on the inner
surface of the outer shield...
 "Reservoir computing (RC) is an approach
for building computer systems inspired by current knowledge of the human brain.
Neuromorphic computing architectures based on this approach are comprised of dynamic
physical nodes, which combined can process spatiotemporal signals. Researchers at
Tsinghua University in China have recently created a new RC system based on
memristors, electrical components that regulate the flow of electrical current
in a circuit, while also recording the amount of charge that previously flowed through
it. This RC system, introduced in a paper published in Nature Electronics, has been
found to achieve remarkable results, both in terms of performance and efficiency.
"The basic architecture of our memristor RC system comes from our earlier work published
in Nature Communications, where we validated the feasibility of building analog
reservoir layer with dynamic memristors..."
 General Dwight D. (Ike) Eisenhower was president
when this article appeared in a 1960 issue of Popular Electronics magazine telling
of plans for the
Federal Communications Commission (FCC) to receive their first computers. Arguments
had to be made to justify the expenditure based on how much money might be saved
in completing the department's duties. Citizen Band (CB) radio license applications
were being received at a rate of 10,000 per month, which was really beginning to
strain the processing efforts when combined with the FCC's other responsibilities.
Mention of Ike always reminds me of the Happy Days episode with Fonzie saying, "I
like Ike. My bike likes Ike..."
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 job openings. HR department employees and/or managers of
hiring companies are welcome to submit opportunities for posting at no charge
(of course a gratuity will be graciously accepted). 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 ...
 KR Electronics designs and manufactures
high quality filters for both the commercial and military markets. KR Electronics'
line of filters
includes lowpass, highpass, bandpass, bandstop 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.
Monday the 24th
 "What's in a name?" Juliet famously asked
that question of Romeo's family name (Montague). Maybe a world created by a bard
of tragedy a name makes no matter, but in the world of product marketing a name
can subconsciously invoke a notion of familiarity and trust, cause a brand to be
unforgettable, or simply provide a clear understanding of what the product is. In
the case of
Goodline Transmission Lines, for which this full-page ad appeared in a 1954
issue of Radio & Television News magazine, the "Good" part of Goodline happens
to be the name of the company owner, Don Good. However, you can be sure he capitalized
on the fortunate surname when branding his transmission lines. In looking at the
ad you can tell that Don is quite adept at wordplay - including double entendre
- and imagery for hawking his wares...
 Modelithics is pleased to announce the release
of the latest version, v22.5, of the
Modelithics COMPLETE Library for use with Keysight Technologies' PathWave Advanced
Design System (ADS). New nonlinear models for 7 Qorvo GaAs pHEMT devices are another
major aspect of version 22.5. These models are validated to 40 GHz and include advanced
features like self-heating and ambient temperature effects. In addition, the release
includes a new nonlinear model for the Mini-Circuits TAV2-501+ E-pHEMT transistor.
This model is validated to 15 GHz and is both substrate and temperature scalable.
Finally, new models are also available for Transcom's TC2381 and TC2384 pHEMT transistors...
 There are still a lot of vintage
vacuum tube-based power amplifiers in service. While this article from the July
1959 edition of Popular Electronics magazine focuses on an audio power amplifier,
the principles apply at least into the lower RF frequencies used by amateur radio
hobbyists and even commercial broadcast equipment. Fundaments of waveform analysis
and amplifier operations are covered. Distortion due to nonlinear characteristics
of active components is a prime concern for maintaining linearity at all frequencies
and for making certain that harmonics and subharmonics are not being blasted into
the ether. Dig the large size classroom demonstration model of the amplifier chassis.
Those kinds of props were popular with both military and civilian schools. This
is part of a many-month "Inside the..." series of articles written by Joseph Marshall...
 Thanks to RF Cafe visitor / contributor
Michael M. for letting me know about an update to CNES RF Propagation
Calculations DLL download hyperlink. In the four months since posting the information,
CNES moved the file. This very handy RF propagation software tool is provided free
of charge by the French organization Centre National d'Études Spatiales (CNES, National
Centre for Space Studies). The PROPAGATION dynamic link library (DLL) contains functions
to compute propagation losses according to ITU-R P. recommendations. Versions
are available for both 32- and 64-bit Windows and Linux operating systems, as well
as for the C and Visual Basic programming languages. Very conveniently, the DLL
functions can be referenced from within an Excel spreadsheet as well...
 Even in the year 2022, there are still plenty
of receivers around that need to be
manually aligned for peak performance. They are not necessarily all older equipment,
either. Super sensitive receivers for radars, radio astronomy, and security systems
are some examples, especially when a combination of center frequency and bandwidth
adjustments are necessary. Of course there are plenty of amateur radio receivers
and vintage AM, FM, and shortwave radios around that are still in service by hobbyists
and collectors. Most of those people probably already know how to tune their radios,
but there are always new enthusiasts just entering into the realm that need a helping
hand. This article entitled "How to Align Receivers" appearing in a 1954 issue of
Popular Electronics magazine will be a big help to them...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
 Lotus Communication Systems began in 2009,
setting up CNC machine shop and RF/microwave assembling and testing lab in Middlesex
Country, Massachusetts. Lotus is committed to highest quality and innovative products.
Each RF/microwave module meets
exceedingly high standards of quality, performance and excellent value, and are
100% MADE IN USA. Lotus' RF/microwave products cover frequency band up to 67 GHz.
Lotus also offers an COTS shield enclosures for RF/microwave prototyping and production.
All products are custom designed. We will find a solution and save your time and
cost. Lotus has multiple 4 axis CNC machines and LPKF circuit plotters.
Sunday the 23rd
 Here is your custom made
Electronics-themed crossword puzzle for October 23rd, 2022. All RF Cafe crossword
puzzles are custom made by me, Kirt Blattenberger, and have only words and clues
related to RF, microwave, and mm-wave engineering, optics, mathematics, chemistry,
physics, and other technical subjects. As always, this crossword contains no names
of politicians, mountain ranges, exotic foods or plants, movie stars, or anything
of the sort unless it/he/she is related to this puzzle's technology theme (e.g.,
Reginald Denny or the Tunguska event in Siberia). The technically inclined cruciverbalists
amongst us will appreciate the effort. Enjoy!
 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...
 Since 1996, ISOTEC has designed, developed
and manufactured an extensive line of RF/microwave connectors, between-series adapters, RF components
and filters for wireless service providers including non-magnetic connectors for
quantum computing and MRI equipments etc. ISOTEC's product line includes low-PIM
RF connectors components such as power dividers and directional couplers. Off-the-shelf
and customized products up to 40 GHz and our low-PIM products can meet -160 dBc
with 2 tones and 20 W test. Quick prototyping, advanced in-house testing and
high-performance. Designs that are cost effective practical and repeatable.
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
Homepage Archive Pages
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- Christmas-themed
items
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