See Page 1 |
2 |
3 |
4 | of the May 2020 homepage archives. Friday 23
 Here are three more
technology-themed comics from vintage of Radio & Television New magazines.
Some issued had multiple comics, but these three had just one apiece, so I combined
them onto a single page. There is a huge list of previously posted comics at the
bottom of the page. With many of these comics, you might need to be familiar with
the mindset of the electronics world back in the day. Today it considered hilarious
today to see a video of someone walking into a street lamp pole while staring obliviously
into a smartphone. In the middle of the last century, fun was made of wives not
understanding their hubbies' hobbies, dealings with servicemen, and and goofy things
do-it-yourselfers of the era were doing.
 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...
 "According to researchers from the University
of Sydney Nano Institute and Max Planck Institute for the Science of Light,
chips that use light and sound, rather than electricity, will be important for
the development of future tech, such as high-speed internet as well as radar and
sensor technology. This will require the low-heat, fast transmission of information.
Scientists in Australia and Europe have taken an important step towards removing
'hot' electrons from the data chips that are a driving force in global telecommunications.
Microchips without electrons will allow for the invention of data processing systems
that don't overheat, have low energy costs, and reduce greenhouse gas emissions.
This foundational work will help scientists invent systems to achieve those aims..."
 "There is no new thing under the sun." -
Ecclesiastes 1:9. "Everything old is
new again." - Peter Allen in All That Jazz. Many such idioms exist regarding
how often things tend to run in cycles; it's just that often times people who think
they are witnessing a new phenomenon are not aware of the previous occurrences.
I have written of examples where 'old timers' lament the attitudes of a fledgling
work force when writings show the previous generation of 'old timers' who worked
with the current 'old timers' in their youth expressed the same type concern. Experienced
Ham operators think newbies cannot carry on the tradition of wireless because they
are not required to learn Morse code anymore to earn a license.
 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.
Thursday 22
 Here is Part 14 of a series entitled
"The
Saga of the Vacuum Tube," by Gerlad Tyne, that appeared in Radio News magazine
in 1944. Part 1 was printed in March 1943, and Part 22, the final chapter,
was published in April 1946. It could have been a stand-alone book. If I manage
to be able to buy issues with some of the other parts, those will be posted as well.
You might be aware of the origins of the amplifying vacuum tubes, beginning with
the accomplishments of Dr. de Forest and his Audion. As with most new technologies,
progress moved very rapidly once other researchers glommed on to the concept. Here,
Mr. Tyne discusses the development of the "Kenotron," "Pliotron," "Dynatron,"
and "Magnetron," by Drs. Langmuir, Dushman and Hull of the General Electric Laboratories,
during the years 1913 to 1921.
 "A
quantum radar using entangled microwave photons has been created at the Institute
of Science and Technology Austria. Also known as 'microwave quantum illumination,'
the demonstration detected objects in a noisy thermal environment - and there are
potential applications for it in low-power biomedical imaging and security scanners,
according to the Institute. 'What we have demonstrated is a proof of concept for
microwave quantum radar,' said researcher Shabir Barzanjeh. 'Using entanglement
generated at a few thousandths of a degree above absolute zero, we have been able
to detect low-reflectivity objects at room-temperature.' Instead of using conventional
microwaves, the researchers entangle two groups of photons - 'signal' and 'idler'
photons..."
 In 2015 we would hardly think of electromagnetic
radiation in the 5 cm wavelength realm as being 'quasi-optical' as far as circuit-based
manipulation is concerned.
Optical wavelengths begin at around 6,300 Å for red light, which is 6.3x10-5 cm,
or 630 nm. The 5 cm wavelength used an example in a 1932 article in
Short Wave Craft magazine is equivalent to 6 GHz. 6 GHz was an
extraordinarily high frequency to be using for communications back then, and the
author did not intend to liken it to anywhere near visible light. Instead, his terming
its properties as 'quasi-optical' referred to how the waves interacted with physical
objects; e.g., reflection, refraction, absorption, and scattering. Barkhausen
oscillations were a popular subject of the era, as I pointed out recently in the
article "The Spook - Another Weird Effect to Haunt TV..."
 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. Please visit Allied
Test Equipment today to see how they can help your project.
 Triad RF Systems, a leading designer and
manufacturer of integrated radio systems and
high performance RF/Microwave amplifiers, is positioned to assist in the deployment
of Bluebird Aero Systems' SpyLite® Mini-UAS (there's a cool animated video on BAS's
homepage). Designed and manufactured by Bluebird Aero Systems, SpyLite® is a mature,
advanced, combat- proven, extended performance electric Mini-UAS, optimized to provide
covert, "over-the-hill" or extended range real-time visual intelligence. SpyLite
is unique in its ability to fly even in severe weather, assuring high operational
availability for 3-4 hours and a communication range of over 50 km (can be
extended up to 80 km). Fully autonomous, the system delivers autonomous ease of
use and high reliability, providing a very versatile and stable ISR platform...
 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."
Wednesday 21
 At least in the U.S., laws regarding the
recording of telephone conversations seem to be constantly changing and vary
from state to state. Violation penalties - including imprisonment - can be severe
in both cases. Some states require that all parties in the conversation be apprised
of the recording, while others only require that at least one party (obviously the
one doing the recording) be aware of it. As mentioned in this 1954 "Macs Radio Service
Shop" story, some areas require that an audible "beep" be sounded at regular intervals
while recording is occurring. With the ubiquitous use of smartphones featuring built-in
recording capabilities, opportunities for recording and being recorded are constant.
Cave participantium, to coin a phrase. As with carrying concealed weapons or just
transporting them between states, if you have any intention of recording a telephone
conversation, you had best check on the most recent statutes before-hand.
 "Engineers from EPFL have successfully demonstrated
a
laser-based microwave generator using integrated photonic chips. This new technology
could have a plethora of useful applications, and may one day be used in 5G wireless
networks, radars, and satellite communications. In order to achieve this feat, scientists
had to dramatically lower the optical losses of the photonic waveguides. These waveguides
are based on silicon nitride, which was manufactured with the lowest loss in any
photonic integrated circuit. With the help of this technology, engineers created
coherent soliton pulses with repetition rates in the X-band and the microwave K-band..."
 Manufacturing
of all our products continues to operate at full capacity as part of the "Essential
Business" community. Professional high frequency
TSA89 series of RF test cables with performance to 40 GHz. Precision connector
choices include; SMA, Type-N, 3.5mm, 2.92mm, & 2.4mm. Key features: High-frequency
point to point cable, light weight rugged double-shielded, flexible cable, low loss <0.68 dB/ft
@ 40 GHz, low VSWR < 1.35:1 (Typical < 1.25:1), RF leakage >-100 dB
to 18 GHz, temperature rated from -55ºC to 125ºC. 100% factory VSWR and insertion
loss tested. Cables are in stock and available immediately from Digi-Key. Made in
the USA.
 Here is an advertisement for Electro-Voice
Manufacturing Company
microphones that I scanned from page 101 of my copy of the February 1943
QST magazine. As with many companies during the World War II era, this
one's theme is the service their products are providing to America's servicemen.
Per the ad: If you were receiving radio messages from men in the midst of earsplitting
battle noises, you'd hear crisp speech undistorted by background sound effects.
Electro-Voice Microphones, in military service, are helping to make it possible.
Similar microphones, designed to achieve such results, will be available for specific
commercial applications ... after our wartime job is done...
 Withwave's new line of
1.85 and 2.92 mm Right Angle Adapters are designed based on precision microwave
interconnection technologies. These 1.85 mm & 2.92 mm / 2.92 mm
to 2.92 mm types are manufactured to precise microwave specifications and constructed
with male and female gender on both side. The precision microwave connector interfaces
ensure an excellent microwave performance up to 40 GHz. Features include: Frequency
range of DC to 40 GHz, VSWR of 1.20:1 (max) @40 GHz, and the body is made
of passivated stainless steel...
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!
Tuesday 20
 Robert Taylor, along with inventing the concept
of "super-modulation," also coined the new communications term "Intelligence
Transmission Efficiency." It refers in part to the ratio of power in the intended
sideband relative to power in the at least partially suppressed other sideband and
carrier. Admittedly, I have not read this material enough to fully comprehend the
concept of super-modulation, but at least based on the Fig. 1 waveform, there
seems to be an element that adds a DC bias to the detected signal due to a nonsymmetrical
(about 0 Vdc) transmitter modulation by pumping more power into the positive peaks.
I'm happy to be corrected by any knowledgeable reader. For that matter, if you have
experience with super-modulation and care to share it with RF Cafe visitors, I'll
be glad to post your comments...
 It would be more than a decade after the
publishing of this article before the first
direct-to-home satellite television broadcasts would be a reality, so it shows
how long plans were being made for such systems. Rural landscapes are still peppered
with the large vestigial C-band (~4 GHz) satellite dishes, many with faded
eyeballs and other clever (and ugly) artwork on them. Before coaxial cable was strung
beyond suburbs, country dwellers who either could not pull in over-the-air broadcasts
from downtown locations or just wanted more viewing options paid dearly for satellite
service. Equipment and installation costs on early systems could run into the $30k
realm. Today's satellite TV systems use much smaller antennas operating in the Ku
band (~12 GHz), with equipment and installation being free with a 2-year commitment.
C-band DBS (direct broadcast satellite) systems are still available, BTW...
 "Fujitsu Laboratories has created a thin
flexible adhesive sheet thermal interface material for heatsinking that achieves
up to 100W/mK thermal conductivity. 'Unlike previous technologies, the
carbon nanotube adhesive sheets are also flexible, making them easy to cut and
handle for use on variety of surfaces,' according to the lab. 'This technology promises
to deliver practical improvements and cost-effectiveness for power modules for electric
vehicles.' Carbon nanotubes have high thermal conductivity along their length, but
poor thermal conductivity across their width, requiring them to be aligned through
the thickness of a layer if it is to be used to conduct heat from one face to the
other..."
 An RF Cascade Workbook 2018 user pointed
out an
error in the minimum noise figure (NFmin) calculation where it sometimes can
go negative. I changed the formulas to never allow NF to go below 0 dB. Instructions
with screen shots are provided if you want to fix it yourself, or please send me
an e-mail and I'll be glad to send you a replacement (v1.20), with apologies.
 Triad RF Systems, a leading designer and
manufacturer of integrated radio systems and high performance RF/Microwave amplifiers,
is pleased to announce the launch of a line of
TRIAD Amplified Radios that extend the range of the most widely used mobile
ad hoc network (MANET) and multiple input multiple output (MIMO) wireless mesh radios
in the industry. The creation and launch of these turnkey high-power radios is in
direct response to customer challenges experienced when Bi-directional amplifier
(BDA) modules are "bolted-on" to a MIMO Radio system. These in-house integrations
frequently fail to achieve the size, weight, performance, and cost objectives (SWaP-C)
required of a long distance radio link. Unmanned aerial vehicles/systems (UAV/UAS)
and ground/surface vehicles (UGV/USV) that frequently operate in harsh weather conditions...
 RF Cafe visitor Kevin A. sent me a
link to another interesting video, this one where the über smart guy on the
Applied Science YouTube channel demonstrates how vulnerable the MEMS-based oscillator
used in iPhones is to even a tiny amount of helium gas. Ben Krasnow, a self-described
technology junkie, does an amazing job concocting experiments to demonstrate and
explain all kinds of processes and phenomena. In this episode, Mr. Krasnow
shows how a partial helium (He) gas pressure as low as 2% will cause MEMs oscillators
in some iPhone and Apple Watch models to stop functioning after mere moments of
exposure. Recovery can take weeks. He mentions that the problem was first identified
in an MRI facility where technicians were exposed to He used for cooling the high
power magnets. Helium, being both nonreactive and one of the smallest atoms, is
notorious for permeating
through many types of materials - even metal!
Electro-Photonics is a global supplier of
RF & Microwave components.
Their products include SMT hybrid and directional couplers, wire bondable passive
components, mounting tabs, filters, transmission lines, and very useful test boards
for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics
team can support your small R&D design requirements with RF & Microwave
test fixtures and save you valuable design and characterization time. Please take
a moment to visit Electro-Photonics' website and see how your project might benefit.
Monday 19
 Robert Taylor claims - without contention
from what I can find - to have invented the concept of "super-modulation,"
whereby the normal "splatter" created by greater than 100% amplitude modulation
(AM) can be mitigated through use of specialized circuits. As with many paradigm-changing
discoveries, much was made of super-modulation in the late 1940s through early 1950s,
and then it pretty much dropped off the charts. The cause might have been that the
sophistication of circuitry needed to keep everything tuned and tracking properly
to prevent harmonic and sideband was deemed not worth the trouble once frequency
modulation (FM) came on the scene. FM quickly gained in popularity due to its relatively
high noise immunity; in fact, many commercial radio broadcast market prognosticators
declared AM to be on life support by the end of the 1950s, with total death to come
shortly thereafter. Mr. Taylor describes in great detail the concept and circuitry
behind his super-modulation system in a two-part series of articles in 1948 issues
of Radio & Television News magazine. You'll need to put your thinking
cap on when reading these.
 "A new sunshade, or visor, designed to reduce
the brightness of SpaceX's Starlink broadband Internet satellites will debut on
the company's next launch, a measure intended to alleviate astronomers' concerns
about impacts on observations through ground-based telescopes, SpaceX founder Elon
Musk said Monday. Beginning with the next launch of Starlink satellites - scheduled
as soon as May 7 from Cape Canaveral - SpaceX will try out a new
light-blocking panel to make the spacecraft less visible to skywatchers and
astronomers. 'We have a radio-transparent foam that will deploy nearly upon the
satellite being released (from the rocket),' Musk said Monday in a virtual meeting
of the National Academies' Decadal Survey on Astronomy and Astrophysics 2020 panel,
a committee charged with setting the top priorities for U.S. astronomy for the next
decade..."
 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. Please visit LadyBug
today to learn how they might help you.
 After seeing the piece I posted about LabVIEW
offering a free
Student Edition of their product, RF Cafe visitor and contributor
Joe Cahak wrote to remind me that last year the company began making the
LabVIEW and LabVIEW NXG Community Edition available free
for non-commercial use. For anyone not familiar with LabVIEW, it provides a drag-and-drop
graphical programming approach to help you visualize every aspect of your application,
including hardware configuration, measurement data, and debugging. "Program the
way you think with intuitive graphical programming. Connect to almost any hardware
with unparalleled hardware support. Quickly gather and visualize data Interoperate
with other software tools." The LabVIEW Community edition includes all of the capabilities
found in the LabVIEW Professional editions, the LINX toolkit for use with Raspberry
Pi, BeagleBoard, and Arduino, plus access to the LabVIEW NXG Web Module for creating
web-based applications...
 By now, most people involved in science and
engineering have seen the iconic photos of cosmic rays and other
subatomic particles leaving a signature of their presence as streaks in a cloud
chamber. Invented by Scottish physicist Charles Wilson, the cloud chamber is a sealed
volume containing super-saturated water vapor that can be ionized by energetic particles
passing through it. The result is a tell-tale whitish line that can be straight
arced, or even a spiral, depending on the nature of the particle. First developed
in the early part of the 20th century, many particles predicted by researchers were
detected and identified. Many unexpected particles were also encountered that gave
physicists reasons to sharpen their pencils and develop new theories to explain.
Similar research and discoveries occur today using super-sensitive electronic detectors
instead of cloud chambers. CERN's Large Hadron Collider (LHC) is currently the world's
grandest particle collider for performing atomic and subatomic particle research...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave filters,
diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity,
and waveguide designs, as well as state of the art high performance suspended substrate
models. Through a continuous process of research and development, they have established
a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop,
diplexer, and more. Established in 1979. Please contact Reactel today to see how
they might help your project.
Sunday 18
 Beginning in the year 2000 and running through
today, May 17, 2020, I have been creating weekly custom
technology-themed crossword puzzles for the brain-exercising benefit and pleasure
of RF Cafe visitors who are fellow cruciverbalists. A database of thousands of words
has been built up over the years and contains only clues and terms associated with
engineering, science, physical, astronomy, mathematics, chemistry, familiar company
names etc. You will never find a word taxing your knowledge of a numbnut soap opera
star or the name of some obscure village in the Andes mountains. You might, however,
encounter the name of a movie star like Hedy Lamarr or a geographical location like
Tunguska, Russia, for reasons which, if you don't already know, might surprise you...
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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