See Page 1 |
2 |
3 |
4 | of the April 2020 homepage archives.
 Whether you are a DIY'er, tinkerer, hobbyist,
experimenter, roustabout, odd-jobber, handyman, jack-of-all-trades, innovator, or
any sort of electronics dilettante to any degree of adeptness from mere abecedarian
to seasoned professional polymath, chances are you can learn something useful from
just about all of John T. Frye's "Mac's Radio Service Shop" techno-drama stories. They appeared
on a monthly basis in Radio & TV News magazine, and then continued
when it became Electronics World in 1959. The varied collection of "dogs"
that piled up on Barney's bench while Mac was on vacation provided a convenient
excuse to touch on a wide variety of equipment types, from record players to radios,
including sets that had fallen victim to "home-talentitis" at the hands of a not-so-capable
owner...
"Fairview-Microwave-Waveguide-Shorts-Shims-4-30-2020.htm" target="_top">
 Fairview Microwave, an Infinite Electronics
brand and a leading provider of on-demand RF, microwave and millimeter wave components,
has launched a new series of "Fairview-Microwave-Waveguide-Shorts-Shims-4-30-2020.htm"
target="_top"> waveguide shorts and shims that are ideal for use in test and instrumentation,
wireless communication, satellite communication and radar applications. Fairview's
new line of waveguide shorts and shims includes 36 models offered in waveguide sizes
ranging from WR-430 to WR-10. This new line is ideal for use in RF test and measurement
applications and provides superior RF performance. Waveguide shims and shorts, or
shorting plates, are commonly included in calibration kits and they are used in
calibration applications. Waveguide shims can also be used to bridge gaps between
waveguide components. These waveguide shims and shorts are compatible with square
and round UG cover and CPR-style flanges...
 The National Company, of Malden, Massachusetts,
which made this
cesium-based Atomichron in the mid-to-late 1950s, began life as
a toy manufacturer. It had an output frequency at the nominal resonance frequency
of cesium - 9192.631830 MHz - and was accurate to better than a second in 600
years. The unit was 7 feet tall and weighed 500 pounds. Modern cesium standards
are more stable and are portable. As of January 2013, the NIST-F1 cesium fountain
primary frequency standard is accurate to within one second every 100 million years!
That's a tad better than the Atomichron, non?
 "The Space Development Agency plans to award
contracts for a mesh network in space this August, with the expectation that an
initial batch of
20 satellites will be placed on orbit during summer 2022. The
agency expects to release a request for proposals for the contracts May 1. The announcement
came during an industry day the agency hosted over the phone April 2. The industry
day was originally slated to take place during the 36th Space Symposium in Colorado
Springs April 2, however, after that event was cancelled due to the circumstances
with COVID-19 the agency opted to hold a virtual industry day instead. According
to SDA Director Derek Tournear, 580 people called in for the event. That first batch
will include 20 satellites and will comprise what Pentagon leaders are calling Tranche
0 of the SDA's Transport Layer, a mesh network of satellites operating primarily
in low earth orbit..."
 3D Smith chart progenitor Andrei Muller
and some of his associates have published a paper on the ACS website entitled, "Radio-Frequency
Characteristics of Ge-doped Vanadium Dioxide Thin Films with Increased Transition
Temperature." It begins: "This work investigates and reports on the radio-frequency
(RF) behavior in the frequency range of 5-35 GHz of germanium-doped vanadium
dioxide (Ge-doped VO2) thin films deposited on silicon substrates via
sputtering and pulsed laser deposition (PLD) with estimated Ge concentrations of
5 and 5.5%. Both films exhibit critical transition temperatures (Tc) of 76.2 and
72 °C, respectively, which are higher compared to that of the undoped VO2 which
undergoes reversible insulator-to-metal phase transition at 68 °C. Both types
of Ge-doped films show low hysteresis..."
Axiom Test Equipment allows you to
rent or
buy test equipment,
repair
test equipment, or sell or trade test equipment. They are committed to providing
superior customer service and high quality electronic test equipment. Axiom offers
customers several practical, efficient, and cost effective solutions for their projects'
TE needs and is committed to providing superior customer service and high quality
electronic test equipment. For anyone seeking a way to offload surplus or obsolete
equipment, they offer a trade-in program or they will buy the equipment from you.
Some vintage items are available fully calibrated. Please check out Axiom Test Equipment
today!
 For many years, I have been scanning and
posting schematics & parts lists like this one that appeared in radio and electronics
magazines in the middle of the last century. Most use vacuum tubes. This
General Electric Model 280 Farm Radio "Radio Data Sheet" was in
the May 1947 issue of Radio-Craft. The Radio Museum website has more information
on the GE Model 280 Farm Radio. Farm radios were designed to work on storage batteries
since until the Rural Electrification Act of 1936 was put into effect, most rural
properties had no commercial AC electric power service. 11 years later, work was
in progress to light up the entire country, but many locations had to wait while
resources went to service war production needs. No actual example of the Farm Radio
could be found online. There are still many people who restore and service these
vintage radios...
Lemos International Technologies is both a designer and manufacturer of
wireless products and a distributor of products from other world-class manufacturers.
A modular approach to wireless connectivity helps eliminate much of the technical
design and testing and also simplifies or eliminates the need for expensive conformance
testing and certification. Ready-to-use Bluetooth, GPS, Wi-Fi, licensed and unlicensed
band products are available. Custom design services can help you achieve success
with your project's unique needs.
"Artech-House-Basic-Radar-Analysis-2nd-Edition-4-30-2020.htm" target="_top">
 Artech House today announced the publication
of "Artech-House-Basic-Radar-Analysis-2nd-Edition-4-30-2020.htm" target="_top">
Basic Radar Analysis, Second Edition by Mervin Budge and Shawn German. This 2nd
edition covers several key radar analysis areas, including the radar range equation,
detection theory, ambiguity functions, waveforms, antennas, active arrays, receivers,
signal processors, CFAR and chaff analysis. Analog signal processors and digital
signal processors of the types used in modern phased array radars are discussed.
Fundamentals of radar analysis including the range equation, detection theory, ambiguity
functions, antennas, receivers, and signal processors for modern radars are also
covered. This book addresses details of the radar range and detection probability
equations and the tools radar engineers commonly use to perform signal processor
and clutter analyses. Packed with details on how to perform radar range equation
and detection analyses, RCS modeling...
 Back in the early 1990s, while working for
a fine Midwestern company that made automated utility meter reading (AMR) equipment,
an older gentleman was hired as a contractor to do some design work. He was an instant
hit with everyone not just because of his engineering prowess, but because of his
stories of the mechanical and analog electronic computers he worked on for the U.S.
Navy. After being commissioned as an ensign at the U.S. Naval Academy in Annapolis,
Maryland, he spent time studying, researching, and designing massive
radar-directed gun pointing systems for battleships. Just as contraptions
like Babbage's difference engine was a marvel of contemporary engineering, so, too,
were those fantastic shipboard amalgamations of gears, switches, vacuum tubes, rheostats,
flywheels, cams, and bearings. Calculations of azimuths and elevations were made
using sum, difference, integrating, and multiplication circuits built of discrete
analog components and electronic valves...
 "Reliable indoor mobile coverage can ease
home broadband capacity challenges during the global health crisis. As the regular
rules for business and social interactions are being torn to shreds as a result
of the Coronavirus pandemic, homeworking is an important lifeline for U.K. companies
trying to maintain some sort of 'normality' for their businesses and employees.
Organisations that have previously avoided or discouraged
remote working for fear of motivational issues have been forced
to rethink their attitudes to home working since the country went into lockdown.
Similarly, those that have historically only permitted hybrid working under special
circumstances have had to formulate a feasible homeworking framework almost overnight,
offer guidance on implementation and come up with innovative ideas..."
 Centric RF is a company offering from stock
various RF and
Microwave coaxial components, including attenuators, adapters, cable assemblies,
terminations, power dividers, and more. We believe in offering high performance
parts from stock at a reasonable cost. Frequency ranges of 0-110 GHz at power
levels from 0.5-500 watts are available off the shelf. Order today, ship today!
Centric RF is currently looking for vendors to partner with them. Please visit Centric
RF today.
 Here are a couple new-old
tech-themed comics from vintage Popular Electronics magazines.
Both have a Ham radio theme, so maybe you need to have been there to appreciate
the scenario... or maybe not. It is possible that the presence of clothes pins on
twin lead or ladder line could de-tune the line, and could crush the internal dielectric
of a coaxial line. There is no metal on boxer shorts, but maybe the clothes pins
are the type with a metal spring. For the other comic, you just need to know what
••• --- ••• is to get it. Enjoy
 Here is an interesting idea from the world
of astronomy - a
Lunar Crater Radio Telescope. RF Cafe visitor
Alan Dewey sent me this
article on plans to build a 1 km diameter radio telescope, operating in the
5 to 100 m wavelength band, in a crater on the far side of the moon. That will
facilitate blocking of Earth-origin radio emissions from the telescope's super-sensitive
receiver. Unlike the 60-year-old 1,000 meter
Arecibo
Observatory radio telescope, the moon-base instrument will sweep a much larger
area of the sky and at a greater frequency than its Earth-based relative. "An ultra-long-wavelength
radio telescope on the far-side of the Moon has tremendous advantages compared to
Earth-based and Earth-orbiting telescopes, including: (i) Such a telescope can observe
the universe at wavelengths greater than 10 m (i.e., frequencies below 30 MHz),
which are reflected by the Earth's ionosphere and are hitherto largely unexplored
by humans..."
 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...
When Do You Expect Your
Business to Return to Normal?
 This is a bummer of a poll done by The Engineer
website asking UK engineering and manufacturing businesses, "When,
if at all, do you expect a return to business as usual?" 13% said never, and
79% said 3-18 months. It's not looking good in the UK or in the U.S. "Do you work
in the UK engineering or manufacturing sectors? If so, when – if at all – do you
expect a return to 'business as usual' once COVID-19 lockdown restrictions are lifted?"
"Withwave-Precision-Right-Angle-Adapters-2d92-2d4-mm-4-28-2020.htm" target="_top">
 Withwave's "Withwave-Precision-Right-Angle-Adapters-2d92-2d4-mm-4-28-2020.htm"
target="_top"> Precision Test Adapters with Right Angle types are designed based
on precision microwave interconnection technologies. These adapters 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 a frequency range of DC to 40 GHz,
VSWR of 1.20:1 (max) @40 GHz, and body made of passivated stainless steel...
 "PCBs? We ain't got no PCBs in our TV sets†...
We don't have to give you no stinking PCBs." That is effectively what the Zenith
television advertisement from a 1958 edition of Radio-Electronics told its potential
customers. According to the Zenith communications department, even though their
head R&D guy, Dr. Alexander Ellett, was "the daddy of printed circuit boards," they stuck with the traditional
point-to-point wiring in all their TV chassis. I have to agree with them from a
troubleshooting and component replacement perspective. There's nothing easier than
heating a solder lug or terminal post to unwrap a leaded R, L, or C either to measure
its value, isolate it from the rest of the circuit for making tests, or to replace
it. There is no worry about solder splatter or bridges, overheating the PCB material
to cause delamination, or lifting metal traces from the surface. There is also no
issue with getting a component lead out of a plated-through hole. Yes, of course
modern circuits need multilayer, high density circuit boards...
Since 1961, MECA Electronics has designed and manufactured an extensive line
of RF & microwave
components for in-building, satellite, radar, radio, telemetry, mobile radio,
aviation & ATC. Attenuators, directional & hybrid couplers, isolators &
circulators, power dividers & combiners, loads, DC blocks, bias-Ts and adapters &
cables. MECA has long been the 'backbone' of high performance wired and air-interfaced
networks such as in-building applications, satellite communications, radar, radio
communications, telemetry applications, mobile radio, aviation & air traffic
communications.
 As this is written, we in the U.S. are nearing
the end (hopefully) of the virtual house arrest period most of the country has had
imposed upon us by overzealous politicians. Part of the "comeback" plan being bandied
about by governors is requiring subjects/citizens to don
cloth face masks when in public places where the arbitrarily conjured
up six-foot "social distancing" rule cannot be easily maintained. Think of the cloth
face mask as the equivalent of an ankle bracelet when venturing outside. There is
no foreseeable end to this "new normal" imposed upon most of the world. Contrary
to what many people believe, the mask's purpose is not to prevent the wearer from
inhaling COVID-19 (aka Wuhan Virus, China Virus, CCP Virus - pick your favorite)
particles, but to arrest the body fluids emanating from the wearer's mouth and nose
from being spewed into the air and/or onto surfaces. In response to the shortage
of N95 type masks that are supposed to stop up to 95% of virus particles, many private
citizens - mostly women - worked with health care personnel to design cloth masks
that are comfortable to wear for long periods of time and are reusable by washing
them...
"skyworks-dual-2p4-ghz-fem-wi-fi-6-laa-4-28-2020.htm" target="_top">
 Skyworks is pleased to introduce the "skyworks-dual-2p4-ghz-fem-wi-fi-6-laa-4-28-2020.htm"
target="_top"> SKY5®-5242-11 a dual 2.4 GHz, 802.11ax high-linearity, high-efficiency
front-end module (FEM) designed for Wi-Fi 6 enabled devices including handsets,
tablets and mobile devices supporting WLAN and Bluetooth® protocols. This highly
integrated FEM includes two transmit and receive chains, an extremely low EVM floor
power amplifier, low noise amplifier with bypass, and a SP3T antenna switch. The
three transmit modes for high linearity, high efficiency and low gain provide optimal
performance. The SKY55242-11 builds on Skyworks' portfolio of revolutionary products
for 5G applications...
 "Despite the time spent with smartphones
and social media, young people today are
just as socially skilled as those from the previous generation,
a new study suggests. Despite the time spent with smartphones and social media,
young people today are just as socially skilled as those from the previous generation,
a new study suggests. Researchers compared teacher and parent evaluations of children
who started kindergarten in 1998 - six years before Facebook launched - with those
who began school in 2010, when the first iPad debuted. Results showed both groups
of kids were rated similarly on interpersonal skills such as the ability to form
and maintain friendships and get along with people who are different. They were
also rated similarly on self-control, such as the ability to regulate their temper..."
 Meteor (burst) scatter communications is
an excellent example of where hobbyists - in this case amateur radio operators -
have contributed mightily to technology. It could be argued that a big part of the
reason for such occasions is that many people involved in science type hobbies are
employed professionally in a similar capacity, and their extracurricular activities
are a natural extension of what pays for the pastimes. It seems amazing to me that
meteor scatter as a means of achieving upper atmosphere reflections of radio signals
went undiscovered until 1953, but evidently that is the case. Meteor scatter is
a very popular form of amateur radio challenge these days, with much activity when
the bigger meteor showers are underway. Prior to 1953, meteor shower study was the
sole domain of astronomers...
 Andrei Muller, co-progenitor of the 3D Smith
chart, and a few of his fellow engineers recently published in Nature magazine
an article entitled, "3D Smith
charts scattering parameters frequency-dependent orientation analysis and complex-scalar
multi-parameter characterization applied to Peano reconfigurable vanadium dioxide
inductors." It begins, "Recently, the field of Metal-Insulator-Transition (MIT)
materials has emerged as an unconventional solution for novel energy efficient electronic
functions, such as steep slope subthermionic switches, neuromorphic hardware, reconfigurable
radiofrequency functions, new types of sensors, terahertz and optoelectronic devices.
Employing radiofrequency (RF) electronic circuits with a MIT material like vanadium
Dioxide, VO2, requires appropriate characterization tools and fabrication
processes. In this work, we develop and use 3D Smith charts for devices and circuits
having complex frequency dependences..."
 ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies for
amplitude and phased matched VNA applications as well as standard & precision
RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the
iBwave component library. They also provide custom coax solutions for applications
where some standard just won't do. A partnership with Newark assures fast, reliable
access. Please visit ConductRF today to see how they can help your project!
 Before the days of cheap stuff from China
(now including exotic viruses that cause politicians to shut down entire economies),
the supply of most common items- particularly high technology - were the domain
of relatively few companies. In some ways it was not entirely a bad thing because,
at least theoretically, the economy of scale enabled larger producers to leverage
bulk buying, well-equipped development labs and manufacturing equipment, and pooling
of talent resources to sell quality products at a lower price. Of course it required
that the company had serious competitors or monopolistic tendencies resulted in
gouging - it's human nature, unfortunately. Hewlett Packed, as much as I appreciate
what the company did for
electronics test equipment, had gotten out of hand with its prices
until Tektronix, Rohde & Schwarz, Fluke, Berkeley Nucleonics, Simpson, Boonton,
Triplet, EICO, Bird, and even RCA began introducing similar equipment at lower prices...
"ConductRF-D38999-RF-Mixed-Signal-Cables-60-GHz-4-21-2020.htm" target="_top">
 As a designated critical industry, ConductRF
continues to operate at full capacity during the COVID-19 pandemic. ConductRF offers
a full line of "ConductRF-D38999-RF-Mixed-Signal-Cables-60-GHz-4-21-2020.htm" target="_top">
D38999, RF and mixed signal cable solutions with performance up to 65 GHz.
D38999 cables are one of our flag ship product capabilities. Standard features include
M85049 backshells, RF contacts for #8, #12 & #16 gauge, BMA & SMPM solutions,
low loss cable types, phase matching available. Custom marking and serialization
also available. Made in the USA. ConductRF coaxial cable assemblies are available
for immediate purchase from
Digi-Key.
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.
 Breaking news from May 1958: "Hardly a month
passes nowadays without the announcement of some 'sensational' new amplifying device.
The great majority of these startling inventions, after their brief flurry in the
popular and technical press, disappear into oblivion. But we believe that the
Tecnetron, just announced in France, has a brilliant and enduring
future." Have you ever heard of a Tecnetron? I didn't think so; neither had I before
reading this article in Radio-Electronics. I guess that pretty much negates the
preceding prediction. The holy grail of the Tecnetron, whose etymology in and of
itself is worth reading about (it's not what you would guess), is that its transconductance
increases with frequency. Construction is such that although it is fabricated from
a shaped rod of germanium, it has a current controlling component that acts like
a cross between a triode vacuum tube and a depletion mode field effect transistor.
My guess is that the rapid improvement of standard semiconductor junction field
effect transistors rendered...
 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...
 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.
 This April 26, 2020,
tech-themed crossword puzzle is bigger than most, figuring that
unfortunately many people have more time to kill due to the situation described
in the sentence formed by 5 Down, 8 Down, 44 Down, 74 Down, 77 Down, and 80 Down.
Otherwise, it contains only clues and terms associated with engineering, science,
physical, astronomy, mathematics, chemistry, etc., which I have personally built
over nearly two decades. Many new words and company names have been added that had
not even been created when I started in the year 2002. 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.
Res-Net Microwave has a complete line of precision
RF &
microwave components including attenuators, terminations, resistors, and diode
detectors for commercial, military, and space applications. Products range from
the small flange type to large 2,000 watt connectorized power attenuators and/or
terminations at frequencies up to 26.5 GHz. In-house photo etch and laser trim
capability. The company is a leader in development and production of the films required
for these type of RF/microwave components. Please check out Res-Net Microwave's
website to see how they can help with your current project.
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. Some quoted items have been shortened
to save space. About RF Cafe.
Homepage Archive Pages
2026:
Jan |
Feb |
Mar |
Apr |
May | Jun | Jul | Aug
| Sep | Oct | Nov | Dec
2025:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2024:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2023:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2022:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2021:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2020:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2019:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2018:
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2017:
Jan | Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2016:
Jan | Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2015:
Jan | Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug | Sep |
Oct |
Nov |
Dec
2014:
Jan | Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2013:
Jan | Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec
2012: 1 |
2 | 3
| 4 | 5
| 6 | 7
| 8 | 9
| 10 | 11
| 12 | 13
(no archives before 2012)
- Christmas-themed
items
|
