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4 of the December 2021 homepage
archives. Friday the 31st
 We are extremely grateful for the support of
advertisers and visitors throughout 2021 and for the entire last two decades. Publishing
RF Cafe (and my
hobby website AirplanesAndRockets.com)
is not just a vocation, but a labor of love for what are both my hobbies and professions.
Here's wishing you and yours a very happy, safe, and prosperous 2022! We'll "take
a cup of kindness yet for
Auld Lang Syne" in your honor at midnight
Sincerely, Kirt & Melanie Blattenberger
 Let us finish off the year 2021 with some
humor; goodness knows we need it after yet another 365 days of what has been awfully
close to a worldwide COVIDictatorship. "15 Days to Slow the Spread" back in early
spring of 2020 mutated like a coronavirus into unlimited variants of government
mandates restricting or destroying freedom of movement, freedom of association,
freedom of personal health choice, freedom of comfort, and numerous other freedoms.
These
electronics-related comics appeared in a couple 1949 issues of Radio-Electronics
magazine. Enjoy (if you still can). I do wonder why the octopus only does the work
of three servicemen...
How Does EMI Affect the Human Body
and Brain?
 The debate has raged since the effects of
electromagnetic (EM) energy has been known:
How Does EMI Affect the Human Body and Brain? While everyone agrees ionizing
radiation is dangerous, opinions range widely on whether or not non-ionizing radiation
influences the human brain and/or body in damaging ways. An entire worldwide community
of "believers" think smart meters and cell towers are
imbedding subliminal
information into people in order to control them (come to think of it, creating
a population of mask wearers was pretty simple - I'm just say'n). Steve Taranovich's
article on the Electronic Design website begins: "On one front, epidemiologic
studies of very-low-frequency electromagnetic fields, particularly cell phones,
show an increased risk of childhood leukemia with estimated daily average exposures
above 0.3 to 0.4 μT. During the last 50 years, man-made electromagnetic energy,
leaking into our environment, has grown exponentially. This energy is not intentional
but does cause interference with our environment as well as our human bodies...
 As a former agent of the U.S. government's
National Unit for ciTizen Subduance (code word: NUTS*), all of my communications
are constantly under surveillance, so merely contacting me by telephone, e-mail,
Skype, telegraph, message in a bottle, or smoke signals virtually guarantees that
"they" will find you and increase the attack already underway against you. For all
that is Holy, spare yourself from the personal torment and hide while you still
can! Seriously, four or five people call me every year wanting to tap into my expertise
on RF energy to help them validate their suspicion - no, wait, absolute certainty
- of currently being the victims of a huge
government conspiracy
whereby special frequencies that have been determined to allow mind control are
attempting to turn them into mindless subjects. I just got off the phone with another
such individual...
 "Radio apparatus of today, including television,
uses practically all of the physical phenomena capable of being controlled by science."
That is the opening line of a 1932 Radio News magazine article discussing
the relatively new technology dealing with the generation AND controlling
of electrical charges. Investigators were beginning to develop formulas and physical
rules for the behavior of electrons - at least in accordance with the accepted Rutherford-Bohr
atomic model. It wasn't until 1929 that
Robert Van de Graaff invented his eponymous generator, before which scientists
like Volta used an electrophorus (Latin for "electricity bearer") to generate static
electrical charges for experimentation by beating a metal disc with an animal skin
to transfer electrons. By 1932, Heisenberg's quantum mechanical theory of matter
was coming into dominance, and not too much later...
 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 16,000 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.
 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.
Thursday the 30th
 Just as with modern day wireless and cellular
network build-outs, the phenomenal costs involved in planning, implementing, maintaining,
upgrading, and expanding coverage for wired networks of yore (as well as what remains
of today's) was/is paid for by paying subscribers. Per this 1948 Radio News
magazine article, American Telephone and Telegraph (AT&T) company's investment
in network service at the time was well over $20,000,000, and that nearly a dozen
basic networks regularly used 90,000 miles of wire. The included photo of the stripped
end of a lead-sheathed multi-conductor cable is an indication of how complex and
massive the effort was. A lot of engineering hours went into developing just the
cables, let alone the citing and building of support towers, burial paths, relay
and switching stations (and getting AC power to them), lightning protection, personnel
and equipment access, and so much more. Aside from the lawsuits and court rulings
regarding monopolistic and anticompetitive practices...
 On-demand television is a concept that has
existed about since the time commercial broadcast TV first came on the scene. Known
as "Boxoffice
Television," it used a "Picture-caster" to scramble the picture so that a subscriber
needed a rented descrambler in order to view the program. A rented key (physical,
not digital) was used to turn the box on and off. The signal went out over a standard
local broadcast tower or even over coaxial line. Channels 2 through 13 were it for
the day. This particular article appeared in Radio & Television News
magazine in 1953. Also, "Will You Pay for TV?," in a 1957 Radio & Popular Electronics
and "Stop Pay TV!," in a 1958 Radio-Electronics...
 ""Researchers at ETH Zurich in Switzerland
have developed a new way of controlling the strength of interactions between particles
in two-dimensional semiconductors. Their technique, which relies on generating so-called
'Feshbach
molecules' and adjusting their interactions using an applied electric field,
might well become a versatile 'tuning knob' to study a broad range of 2D solid-state
platforms in the laboratory. Feshbach resonances allow researchers to tune the interaction
strength between quantum entities by bringing them into resonance with a bound state.
In the ETH team's work, these states correspond to an exciton (an electron-hole
pair) in one layer of a two-dimensional material bound to a hole in the adjacent
layer. When the exciton (which is created by exciting the material with light) and
hole overlap in space, the hole in one layer can then tunnel to the other layer
and form an interlayer exciton-hole..."
 This second part of the "Radar
Principles" article by British engineer and researcher Dr. R.L. Smith-Rose provides
a historical perspective of the very beginnings of radar systems. It appeared in
the May 1945 issue of Radio-Craft magazine. Although alluded to by technical visionaries
like Hugo Gernsback, George Orwell, Jules Verne, H.G. Wells, et al, for use in target
detection and ranging (but rarely speed, oddly enough). According to Dr. Smith-Rose,
the first use of radio waves for detection and distance measurement was in atmospheric
studies to characterize the ionosphere, in a bistatic configuration. It is an interesting
and quick read, and you might even be introduced to the concept of a squegging...
 "Tech giant Apple has reportedly issued significant
stock bonuses to some engineers in an attempt to prevent top talent leaving for
Facebook. The retention bonuses are as much as
$180,000 for key engineering talent. Bloomberg reports that Apple is attempting
to prevent its top talent from leaving to join tech rivals like Facebook (now known
as Meta) by offering significant stock bonuses. The company informed some of its
engineers in silicon design, hardware, and select operation groups last week that
they would be receiving out-of-cycle bonuses issued as restricted stock units. The
shares vest over four years which provides an incentive for the engineers to stay
at Apple. According to individuals with knowledge of the matter, the bonuses came
as a surprise to many..."
 Honestly, I don't remember why I scanned
this advertisement for
Sarkes Tarzian recorder tape that appeared in a 1962 edition of Popular Electronics
magazine. Maybe it was to illustrate how far personal recording technology has come
in the half century since the ad ran. Today's recorders are in the form of a very
small digital device the size of a pack of gum (or any smartphone can be used),
and not only is the miniature recorder capable of storing longer sessions, but the
quality of the recording is almost certainly better. The cost of a digital recorder
is about the same in inflated dollars as a spool of tape was in 1962...
 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 ...
 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.
Wednesday the 29th
 Technology builds on its own successes in
order to evolve. This article from a 1948 issue of Radio News magazine
reporting on the relatively newly perfected
electron microscope. As electronics moved from the macro scale in the form of
vacuum tubes and large, high voltage- and power-handling leaded components (resistors,
inductors, capacitors) to semiconductors and smaller, lower voltage and power components,
using a standard optical type microscope was not good due to small features on the
IC die. As more powerful microscopes were developed, engineers and scientists were
able to develop semiconductor circuits with smaller features. That enabled more
compact, higher performance electronic microscopes to be built ... and the cycle
continued to where we are today. It is sort of another way of looking at Moore's
law...
 Antenova Ltd, the UK-based manufacturer of
antennas and RF antenna modules for M2M and the IoT, has published a Quick Guide
entitled "A
Guide to 4G and 5G Frequency Bands." It helps answer the question of whether
you should use a 4G or 5G cellular antenna for your new product? The dawn of 5G
is set to open up a world of new possibilities for wireless devices. But 5G networks
will coexist with older 4G and NBIoT networks for some time to come. This guide
will help you decide which is perfect for your project. The guide will explore:
How to match a frequency band to your application, Choosing a technology based on
where your device needs to operate, Achieving certification for 4G and 5G devices,
A summary of the 4G LTE bands and 5G frequency bands used in major territories...
 Once radios in the family car became a standard
accessory, a push ensued to make them cheaper, more reliable, and service-free.
A major Achilles' Heel was the high voltage power supply required to energize vacuum
tubes. Known as vibrator power supplies due to using an oscillator to convert the
battery's 12 DC supply (some autos still used 6 V systems) into AC that could
be transformed up to the 300 volts used by most tubes of the day, most early failures
were attributed to the circuits. They also caused annoying noise in the audio output
if careful filtering and installation was not performed. Having been invented only
a couple years earlier, transistors were being designed into the power supplies,
but
low-voltage tubes were still needed for the electronics. In response to the
demand, low-voltage tubes...
 "When faced with a repair bill that costs
half of what you paid for your car, do you go through with the expensive repair,
bring it to the junkyard, or sell it for parts? Finnish Tesla owner Tuomas Katainen
decided to do something a little more extreme - but arguably a lot more satisfying
- when faced with such a situation: he watched his car go up in flames, as noted
in a report from Gizmodo. Katainen handed his 2013 Tesla Model S over to Pommijätkät,
a group of explosion experts on YouTube who loves to make things go 'boom,' after
he was quoted $22,600 for a battery replacement. 'Well when I bought that Tesla,
the first 1,500km [932 miles] were nice,' Katainen recounted. 'Then, error codes
hit..."
 As a case in point about my claim with an
earlier post featuring Bob Berman's factoids on astronomy, this article from a 1956
edition of Popular Electronics illustrates how vital electronics are in
the various fields of science. It has only been fairly recently that astronomers
have been "looking" at stars and planets outside of the visible wavelengths. Renditions
of the sky in both shorter and longer wavelengths show in some regions a vastly
different universe. In 2015, a comprehensive mapping of the entire known universe
in the microwave realm revealed the largest contiguous feature ever detected - dubbed
"The Cold Spot." Such discoveries could not be made without sophisticated electronics.
The same can be said of medicine, biology, mechanics, finance, etc. Reported here
are some of the earlier detections of radio signatures from our planets...
 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!
 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.
Tuesday the 28th
 For many years, Radio-Electronics
magazine featured a monthly column entitled "News
Briefs," which as the name suggests reported on breaking industry news. It could
be the announcement of a significant new invention, research, a tradeshow event,
recognition of someone's achievement, or any item deemed worthy of making public.
Some months flourished with interesting (to me) tidbits while others had none. The
November 1957 issue was middle of the road, so to speak. One that might interest
you is that RETMA Changes Name. The Radio-Electronics - Television Manufacturers
Association has changed its name to Electronic Industries Association (EIA) - the
name it still bears to this day...
 Hugo Gernsback, ever the prolific author
on futuristic technology of the wireless nature, proposes here in a 1944 issue of
Radio-Craft magazine a new form of sea-faring weapon that would project
an practically unstoppable assault on enemy ships: a high speed,
remote controlled torpedo. After being launched from the safety of a location
far out of range of enemy fire, a human controller in an airborne platform (i.e.,
an airplane) would, using navigation advice provided by spotter aircraft (forward
air control in modern terms), steer the explosive craft over potentially long distances
to direct hits on battleships, destroyers, landing craft, patrol boats, etc. Fortunately
for all involved (well at least for Allied nations), the war would only last another
year and a half by the time this concept was published so it did not come to fruition
in time to test...
 Microwave & RF magazine has
been publishing sections of their
2021 Salary & Career Report based on feedback from engineers and managers.
This portion is on Continuing Education. Findings show education level is staying
on par, with the majority electing for online seminars, webcasts and instructional
videos, and websites like RF Cafe ()my addition) for keeping skillsets current.
The report begins: "'Every project involves so many different technologies that
it’s hard to keep up,' says a respondent to our 2021 Salary & Career Report
Survey. In a nutshell, that's the overriding sentiment among engineers when it comes
to continuing their engineering educations. In our survey, we asked you to update
us on your current level of education and how you prefer to learn about new technologies
and skills. Does your employer encourage continuing education by footing the bill..."
 "Researchers are rapidly knocking down the
barriers to boosting chip density. In the quest to keep Moore's Law going, you might
imagine wanting to shrink transistors until the smallest part was just an atom thick.
Unfortunately, that won’t work for silicon. Its semiconducting properties require
a third dimension. But there is a class of materials that act as semiconductors
even though they are two-dimensional. And new results from some of the biggest chip
companies and research institutions show that these
2D semiconductors
could be a good path forward once silicon's limits are reached. In work presented
this week at IEEE International Electron Devices Meeting, in San Francisco, researchers
at Intel, Stanford, and TSMC presented separate solutions to one of the most vexing
barriers to making 2D transistors..."
 In the 1930s, electricity and electronics
were mysteries to most of the population. The concepts were relatively new and few
had a firm grasp on the technology. That reality was exploited by Hugo Gernsback
during the
1934 Electrical Exposition to challenge attendees to discover how the radio
receiver sitting on the top of an empty, clear glass case was being powered. It
was a clever ruse that reportedly stumped most people. The secret is revealed here
in this 1934 issue of his Radio-Craft magazine. BTW, my guess is that an
even smaller proportion of our current citizens would be able to figure it out,
or for that matter even realize that maybe there should be a power source of some
sort...
 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 object has been built to fit proportionally on the provided
A-, B- and C-size drawing page templates (or can use your own). Stencils 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...
 Innovative Power Products (IPP) has over
30 years of experience designing & manufacturing RF & microwave passive
components. Their high power, broadband
couplers, combiners, resistors, baluns, terminations
and attenuators are fabricated using the latest materials and design tools available,
resulting in unrivaled product performance. Applications in military, medical, industrial
and commercial markets are serviced around the world. Please take a couple minutes
to visit their website and see how IPP can help you today.
Monday the 27th
 This particular article from a 1940 issue
of Radio News magazine touches on two of my hobbies - airplanes and Amateur
radio. Whereas most of my flying experience is with all forms of models, here is
a group of Hams who provided logistical radio communications during the
3rd Open American Soaring Contest, held in Lockport, Illinois. W9USB was the
call sign granted by the FCC especially for the event. Such a contest requires administration
and coordination of air and ground aircraft movement, tow winch operation, pilot
status, event scheduling, and emergency services if required (fortunately, none
were). Being an all volunteer effort, the "Prairie Dogs" subdivision of the "Hamfesters
Club" of Chicago. As pointed out in the article, the highly successful operation
was a great public service demonstrating the capability and utility of Amateur radio.
Many major Ham equipment manufacturers...
 "Researchers from Georgia Tech Research Institute
(GTRI) have developed a new general-purpose, high-performance monolithic microwave
integrated circuit (MMIC) for the
direct filtering and processing of radio frequency (RF) signals in the microwave
and millimeter-wave spectrum. The IC is designed to meet the need for high-frequency,
wideband analog electronics for specialized applications with small form factors
and challenging weight and power budgets. The device, known as Transversal Radio
Frequency Filter Integrated Circuit (TRAFFIC), has demonstrated a fully-reconfigurable
10-to-1 analog finite impulse response (FIR) filter for tunable filtering across
a wide band of frequencies from 2 to 20 GHz. TRAFFIC was implemented in silicon-germanium
(SiGe) technology, a platform designed..."
 As mentioned in an earlier article, National
Radio Institute (NRI) was one of the first companies to exploit the burgeoning field
of electronics in the early part of the last century. They invested heavily in facilities
and resources for producing educational material for both classroom and correspondence
courses. Up until sometime in the early 1990s when throw-away electronics and almost
total offshore manufacturing became the rule rather than the exception, there were
always large advertisements in magazines offering to rescue floundering career seekers
with promises of untold opportunities and riches from servicing radios, televisions,
home appliances, and more. That is not to say the courses were not valuable
- they were...
 Here is a Christmas-themed "Carl & Jerry" episode from the December 1958 issue of
Popular Electronics magazine. Carl and Jerry, if you are not familiar with
them, are a couple electronics-savvy teenagers who, in the style of "The Hardy Boys,"
manage to get involved in a series of criminal investigations. With headquarters
based in their parent's basement, the two friends cobble up strategies and contraptions
for snaring bad guys, bedazzling unsuspecting neighbors and classmates, and assisting
people in need of techno-capable assistance. They have quite an impressive collection
of test equipment and radio gear at their disposal per the one drawing herein. In
this episode we are introduced to the word "osculation." If you already knew its
definition, you're one up on me...
 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...
 Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly
for design engineers needing low volume or prototype multi-layer printed circuit
boards. Free Passive Components: Bittele
Electronics is taking one further step in its commitment of offering the best service
to clients of its PCB assembly business. Bittele is now offering common passive
components to its clients FREE of Charge.
Sunday the 26th
 This is the
final RF Cafe Crossword Puzzle for 2021. Where has the year gone? Thank you
for being a loyal visitor! Look for two clues with asterisks (*) relative to this
theme. Otherwise, it has 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)...
 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...
 Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products
such as RF signal generators, RF synthesizers, RF power detectors, mixers, up /
downconverters. Since the conception of WFT, we have introduced products that have
been purchased by a wide range of customers, from hobbyists to education facilities
to government agencies. Worldwide customers include Europe, Australia, and Asia.
Please contact Windfreak today to learn how they might help you with your current
project.
Friday the 24th
 Anritsu has been a global provider of innovative
communications test and measurement solutions for more than 120 years. Anritsu manufactures
a full line of innovative components and accessories for
RF and Microwave Test and Measurement
Equipment including attenuators & terminations; coaxial cables, connectors &
adapters; o-scopes; power meters & sensors; signal generators; antenna, signal,
spectrum, & vector network analyzers (VNAs); calibration kits; Bluetooth &
WLAN testers; PIM testers; amplifiers; power dividers; antennas.
 Call forwarding, call waiting, call holding,
speed dialing, conference calling, all of these features are taken for granted with
mobile phone and VOIP phone service and are included in the base service package.
It will cost you extra if you subscribe to a local legacy POTS (Plain
Old Telephone Service) provider. What is standard now was considered ground-breaking
technology in the early1960s when this article appeared in Popular Electronics
magazine. When phone calls were processed via human operators manipulating patch
cords and then electromechanical relays, it was enough to simply place a successful
call and not be interrupted or disconnected. Once transistorized circuits entered
the scene, much more was possible, and phone system engineers were quick to exploit
the technology. Sophisticated decision making requires both logical circuits and
a form of memory. Logic could be provided using hard-wired diode steering...
 Here are a few of my favorite
Christmas
music videos. They include an eclectic mix of Cloverton, the Trans-Siberian
Orchestra, an unlikely duet sung by Bing Crosby and David Bowie, and Casting Crowns.
Watching the instruments being played really enhances the effect of the song. I
used to have the videos embedded in this page for easy viewing all in one place,
but each year on some of them I have to go find new hosting location because the
previous year's had been removed. This time I am just linking to the YouTube (and
other) web pages. The U.S. Air Force Band performance at the Smithsonian Air and
Space Museum is my newest addition for 2020...
 "Université Paris-Saclay and Université Côte
d'Azur in France have reported work on germanium tin on insulator (GeSnOI) laser
structures 'The key advantage of this GeSnOI platform is its ability to combine
active laser structures with passive SiN circuitry from the near-infrared to the
mid-infrared. It represents a new paradigm for infrared Group-IV photonics that
eliminates the need for III–V laser integration.' Being a group-IV compound/alloy,
GeSn is easier to integrate with the mainstream (group-IV) silicon (Si) complementary
metal-oxide-semiconductor (CMOS) manufacturing infrastructure that powers the modern
world. Band and strain engineering of GeSn has led to hopes of efficient light emission
through direct-bandgap transitions, as opposed to the generally non-radiative indirect
bandgaps of Si and pure Ge..."
 Now here is a profound ode to one of the
most noble of technician genres ever to tweak a receiver front end or to change
out a transmitter magnetron -
The Radar Man!! It appeared in a 1960 issue of Popular Electronics magazine.
Some of you know that I worked on airport surveillance and precision approach radar
in the USAF, so my bias is established. Hmmm... now that I read the poem more carefully,
I realize that it is not complimentary at all. It must have been one of those jealous
TACAN or satellite communications technicians that wrote it!
 With 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...
 SF Circuits' specialty is in the complex,
advanced technology of PCB fabrication and assembly, producing high quality multi-layered
PCBs from elaborate layouts. With them, you receive unparalleled technical expertise
at competitive prices as well as the most progressive solutions available. Their
customers request PCB production that is outside the capabilities of normal circuit
board providers. Please take a moment to visit San Francisco Circuits today. "Printed
Circuit Fabrication & Assembly with No Limit on Technology or Quantity."
Thursday the 23rd
 In the early 1960s,
nickel-cadmium (NiCad or NiCd) batteries were the way of the future due to a
combination of high charge storage density and recharging ability. Carbon-zinc (C-Zn)
cells were well established by then and had performed reliably during World War II
and in Korea. Alkaline batteries were considered the de facto high standard for
critical applications that required longer life and higher current than C-Zn could
supply, but were (and still are) considerably more expensive. Mercury cells exhibited
a fairly constant voltage level during useful life, which made them preferable for
applications with a low voltage variance tolerance. Lithium-ion (Li-Ion) cells,
those things that rule today's battery domain, were not much more than a laboratory
curiosity at the time. This 1962 Popular Electronics magazine article provides a
good bit of history...
 "Advances in communications enable a safer
world in many ways, ranging from health monitoring and diagnosis to reliable connectivity
for critical defense systems. However, radio frequency (RF) signals may negatively
affect health if exposure is too high, as in the case of
errant RF emissions. Concerns also arise over threats to disable critical communications
from an event such as an electromagnetic pulse (EMP). An EMP would halt the functioning
of much of society by disabling electronics. Using RF signals to trigger attacks
with drones or explosive devices is also an issue. Drones have the potential for
illegal or threatening uses. While spectrum monitoring cannot prevent these issues
and attacks, it can detect signs beforehand..."
 Klystron is a household word these days -
literally - since every microwave oven contains one. Do you know who registered
the trade name originally? Per this advertisement from a 1945 edition of Radio-Craft
magazine, Sperry Gyroscope Company did. It was actually scientists at Stanford University
(Russell and Sigurd Varian) who developed the klystron tube, financed by Sperry
as part of its blind aircraft landing system. In an act of magnanimity that would
never be considered in today's competitive markets, Sperry issued the following
statement: "From now on, the name Klystron belongs to the public, and may be used
by anyone as the designation for velocity-modulated tubes of any manufacture." Right
decent of them.
 Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his November 2021 newsletter that
features his short op-ed entitled "My
Prediction for 2022," where he prognosticates in some specificity that the major
problems with millimeter technology will be solved for 5G, the defense market will
grow for RF and microwave manufacturers, the gap in the digital divide will further
close and the commercial satellite market will provide significant revenue to the
industry. An admission to getting one last year's major predictions wrong is also
included...
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!
 Alliance Test Equipment sells
used / refurbished
test equipment and offers short- and long-term rentals. They also offer repair,
maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP,
Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization
with ability to source hard to find equipment through our network of suppliers.
Alliance Test will purchase your excess test equipment in large or small lots. Blog
posts offer advice on application and use of a wide range of test equipment. Please
visit Allied Test Equipment today to see how they can help your project.
Wednesday the 22nd
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 object has been built to fit proportionally on the provided
A-, B- and C-size drawing page templates (or can use your own). Stencils 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...
 You're not going to find much information
about the "Futuramic
Antenna" by doing an Internet search. I had never head of such an antenna before
seeing this article about it in the October 1952 issue of Radio-Electronics magazine.
Although it was the trade name of a design by Channel Master, the authors (company
engineers) claim it is a variation of a Yagi antenna which provides a much wider
bandwidth by stacking multiple antennas and phase adjusting them in a combiner.
The story takes place in the era shortly after the FCC ended a freeze on new television
broadcast station licenses (1948) because channel assignments in the spectrum were
being changed and UHF channels added, rendering some older equipment in need of
modification or replacement. The effort was a model of bureaucratic chaos...
 "Magnets
are used in so many of our everyday objects including cell phones and in the strip
of a credit card or a hotel key. They even power the engine in your vacuum. And
as most computers use magnets to store information, finding ever thinner magnets
is key to faster, lighter electronics. Graphene, a material that is one atom thick,
was discovered in 2004 and won the 2010 Nobel Prize in physics. While graphene is
not magnetic itself, it triggered the interest of searching for
atomically thin magnets. In 2017, scientists found an ultrathin, magnetic material
just three atoms, or one atomic unit, thick. But this material, called chromium
triiodide, had a simple magnetic moment arrangement - the spin of the electrons...
 An RF Cafe visitor sent this equation to
me a few years ago. It can be found all over the Internet (including here), but
I cannot determine a definite origin. Mathematicians claim that math can explain
everything in the universe, which is not quite true. It can't for example, explain
why my next-door neighbor is a junk hoarder. This
Christmas equation
does not appear to begin with a particular application; it looks like something
from a set of textbook end-of-chapter problems. Even if you don't celebrate Christmas,
it provides a secondary benefit by demonstrating rules for the manipulation of logarithms
and exponents along with basic algebraic rearrangements of terms.
 For many years I have been scanning and posting
"Radio Service Data Sheets" like this one featuring the International
Kadette Model 1019 A.C. Superhet Radio in graphical format, and also include
some textual content to serve as search engine keyword targets. 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. As shown in the thumbnail
image, you can still find many of these old radios in condition ranging from disaster
to fully restored. I will keep a running list of all data sheets to facilitate a
search...
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 16,000 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.
 RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
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.
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- Christmas-themed
items
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