See Page 1 |
2 |
3 |
4 | of the February 2020 homepage
archives. Friday 14
 Unlike many electronics enthusiasts including
hobbyists, salesmen, servicemen, and commercial and domestic users, Mac McGregor
was an early-on believer of the ultimate replacement of vacuum tubes by transistors.
Only a decade old and not yet adopted by a lot of manufacturers (to their ultimate
demise in some cases),
transistors were fighting a major battle to gain acceptance and trust by the
public. Not only were transistors still more expensive than an equivalent vacuum
tube, but the reliability was not as good - most times due to designers not properly
accounting for their special needs for protection against voltage extremes. Once
the price of transistorized products fell into parity with their predecessors, consumers
quickly adopted the products because of the markedly smaller sizes and lower power
consumption...
 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 ...
 Anatech Electronics offers the industry's
largest portfolio of high-performance standard and customized RF and microwave filters
and filter-related products for military, commercial, aerospace and defense, and
industrial applications up to 40 GHz. In their
February Product Update, Anatech has introduced a surface mount 5245-5855 MHz
cavity bandpass filter with 40 W power handling, a 5550 MHz (902 MHz
bandwidth) cavity bandpass filter, and a surface mount 5400 MHz MonoBlock ceramic
bandpass filter . Custom RF power directional coupler designs can be designed and
produced when a standard cannot be found, or the requirements are such that a custom
approach is necessary...
 I usually try to post something a little
less serious and technical on Fridays to help everyone wind down from the long week
just passed. It could be a Carl & Jerry or a Mac's Radio Service Shop story,
an electronics quiz, or even something I found out on the Internet. This time it
is a "believe-it-or-not" type feature entitled "Curiosa
in Radio," about radio manufacturing, operating, and infrastructure. One factoid
claims "Only 1.1% of set manufacturers in business in 1924 are building sets today."
It could due to being in the middle of the Depression Era so almost nobody was making
/ buying radios, but more likely it reflects the reality of the many people who
jumped into the fledgling radio industry early on and then could not gain market
share. Enjoy.
 "The
Sensitivity Conjecture has stood as one of the most important, and baffling,
open problems in theoretical computer science for nearly three decades. It appears
to have finally met its match through work by Hao Huang, an assistant professor
of mathematics at Emory University. 'I've been attacking this problem off and on
since 2012,' Huang says, 'but the key idea emerged for me just about a week ago.
I finally identified the right tool to solve it.' Huang posted the proof on his
home page and it soon generated buzz among mathematicians and computer scientists
on social media, who have praised its remarkable conciseness and simplicity. The
Sensitivity Conjecture relates to Boolean data, which maps information into a true-false,
or 1-0 binary. Boolean functions play an important role..."
 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.
Thursday 13
 Unlike many awards that are presented more
for the publicity sake of the presenting entity than for the benefit of the recipient,
when the Indiana Radio Council named
John T. Frye the state's outstanding amateur radio operator of the year,
it was because he truly deserved it. He performed communications operation during
weather-related emergency scenarios. For many years, Mr. Frye would further
indirectly promote Indiana through his technodrama "Carl & Jerry" and "Mac's
Radio Service Shop" series of stories published in Radio & Television News
and Popular Electronics magazines. Also mentioned in this instance of "The
Radio Month" column in Radio-Electronics magazine is how TV sets owned by students
attending the Valparaiso Technical Institute...
 Now this is my kind of cellphone! On her
website, Maker Justine Haupt give the motivation for all the work: "Why a
rotary cellphone? Because
in a finicky, annoying, touchscreen world of hyperconnected people using phones
they have no control over or understanding of, I wanted something that would be
entirely mine, personal, and absolutely tactile, while also giving me an excuse
for not texting." It uses an Arduino controller and a custom-designed slick-looking
3D-printed enclosure. "The point isn't to be anachronistic. It's to show that it's
possible to have a perfectly usable phone that goes as far from having a touchscreen
as I can imagine, and which in some ways may actually be more functional." It brings
a tear to my eye ;-)
 "Sapcorda Services GmbH, a GNSS service provider
focusing on the emerging high-precision GNSS mass markets, has released its SAPA
(Safe
And Precise Augmentation) Premium GNSS positioning service. The SAPA service
enables mass-market GNSS devices to operate with increased accuracy and reliability
across Europe and the continental U.S. The service's technology unlocks advanced
performance with instantaneous sub-decimeter position accuracy for devices used
in all market applications. SAPA is delivered using the open industry-recognized
SPARTN (Safe Position Augmentation for Real-Time Navigation) format, which allows
efficient delivery..."
 The
thyratron is not necessarily a familiar type of vacuum tube to most RF and microwave
electronics practitioners unless they happen to be involved in radar, imaging (x-ray),
particle accelerators, etc.† It is basically a high speed, high current switch used
in pulse forming networks for firing magnetrons (via a high-voltage transformer).
Both the S-band airport surveillance radar and the X-band precision approach radar
I worked on in the USAF employed thyratrons. The X-band radar had been modified
by the time I came on the scene to use a solid state thyratron (one of the earliest
adaptations), but the S-band radar still used its original vacuum tube thyratron.
While I don't recall for certain, I believe the thyratron in the thumbnail image
is the one it used. The accompanying ruler...
 "Researchers at the Loughborough University
have created a unique device which will unlock the
elusive terahertz wavelengths and make revolutionary new technologies possible.
Terahertz waves (THz) sit between microwaves and infrared in the light frequency
spectrum, but due to their low-energy scientists have been unable to harness their
potential. The conundrum is known in scientific circles as the terahertz gap. Being
able to detect and amplify THz waves (T-rays) would open up a new era of medical,
communications, satellite, cosmological and other technologies. One of the biggest
applications would be as a safe, non-destructive alternative to X-rays. However,
until now, the wavelengths..."
 RF Cafe typically receives 8,000-15,000
website visits each weekday and about half that on weekends.
RF Cafe is a favorite of engineers, technicians, hobbyists, and students all
over the world. With more than 8,000 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, Facebook, and Twitter. If you need your company news to be seen,
RF Cafe is the place to be. Advertising
begins at $45/month.
 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!
Wednesday 12
 This Popular Electronics article
by at-the-time editor Oliver Ferrell offers recommendations on how to spot a good
deal in
grab-bag assortments of electronics components when shopping for good deals,
whether it be at a retail outlet, flea market, or Hamfest. The advice is a useful
today as it was then. Little did anyone know that half a century later there would
be another source for cheap parts that would dwarf what had previously been available
- the Internet, and in particular, eBay. Mr. Ferrell mentions the term "radio
row," which was a downtown area in many cities where surplus equipment dealers peddled
their wares. In the 1950's and 60's, a lot of it was left over from wars, and included
not just electronics parts but also mechanical gear. Two of the more famous "radio
row" areas were in New York City and Tokyo, which were covered in two other articles
entitled "Radio a la Cortlandt Street!," and "Akihabara Tokyo's 'Radio Row'," respectively...
 Providing full solution service is our motto,
not just selling goods. RF &
Connector Technology has persistently pursued a management policy stressing
quality assurance system and technological advancement. From your very first contact,
you will be supported by competent RF specialists; all of them have several years
of field experience in this industry allowing them to suggest a fundamental solution
and troubleshooting approach. Coaxial RF connectors, cable assemblies, antennas,
terminations, attenuators, couplers, dividers, and more. Practically, we put priority
on process inspection at each step of workflow as well as during final inspection
in order to actualize "Zero Defects."
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 ...
 Multipath signal interference is as prevalent
today as it was at the beginning of radio communications - maybe more so since there
are typically more reflective obstacles between the transmitter and the receiver.
The evidence of multipath with digital communications, be it voice, Internet page
viewing, or movies, is slowness in transmission as opposed to the analog case where
garbled speech on radio and ghosting pictures on television are the evidence. High
data rates with digital transmissions typically mask the packet errors and their
necessary re-transmission; it all happens before the buffered information is presented
to the listener / viewer. However, there is no such buffering of over-the-air radio
or TV transmissions so evidence of multipath is immediately noticeable. I remember
how sometimes...
 Copper Mountain Technologies and Maury Microwave
will present a free webinar entitled "Introduction
to Load Pull," on February 20, from 1:00-2:00 pm EST. "This seminar will
cover the A-Z of load pull, starting from basic concepts and techniques and ending
in real-life examples of common applications. Participants will learn the reasons
why we perform load pull, the various load pull methodologies and their advantages
and disadvantages, a dive into the applications of PA design, model extraction and
model validation using load pull, and finally examples of applying vector-receiver
load pull using Copper Mountain Technologies' Cobalt-series VNAs to these applications..."
 "MIT/Harvard researchers developed a tunable
THz-range source using a laser and nitrous oxide, while a team in Mexico characterized
the minute X-ray emissions due to
triboluminescence when pulling adhesive tape. It's always been a challenge to
generate 'THz') waves, the span of electromagnetic spectrum between millimeter and
optical wavelengths and generally defined as wavelengths from 1 to 0.1 mm or 300
to 3,000 GHz. While there are vacuum-tube and solid-state devices and assemblies
that can do so, these bring many challenges and limitations. Now, a team at MIT
in close collaboration with one at nearby Harvard University has developed a laser-pumped,
gas-based THz source that can be fine-tuned over 37 lines spanning..."
 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.
Tuesday 11
 "Micro" as applied to electronics is relative,
depending on which decade you reference. In the 1940s, a micro-size electronic assembly
might have included "peanut" vacuum tubes and even some sort of printed circuit
board. That was a huge step down in size from standard size tubes with point-to-point
wiring between tube sockets and solder lugs on switches, potentiometers, variable
capacitors, etc. Fixed value leaded resistors, capacitors, and inductors, and transformer
wires connected to those lugs as well as to many terminal strips installed specifically
for making connections. Once transistors came on the scene in the 1950s, a new round
of
miniaturization took place based on not just a significantly smaller size of
solid state transistors and diodes, but their lower voltage and current requirements
meant ancillary components could be made smaller as well due to lower voltage...
 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.
 Well, this might get some dander up amongst
the believers that Sir Robert Watson-Watt is "the
Father of Radar." In the December 1957 edition of Popular Electronics magazine,
Colonel William R. Blair was given that honored designation based on his work on
a pulse-echo method of direction finding in the 1920s. The Wikipedia entry for Col.
Blair refers to him more specifically as the "Father of American Radar." William
R. Blair was awarded U.S. patent #2,803,819, titled "Object Locating System," on
August 20, 1957 - a full 13 years after the patent application was submitted. Watson-Watt
was issued a patent in 1935 on a radio device for detecting and locating an aircraft.
His research was born out of an investigation into a "death ray" which had reportedly
been invented by the Germans.
 This is a great idea - and long overdue!
"The liquid crystal display
blocks the sun in just the right spots. The automotive sun visor has been around
for nearly a century, first affixed in 1924 as a 'glare shield' on the outside of
a Ford Model T. Yet despite modest advances -lighted vanity mirrors, anyone? - it's
still a crude, view-blocking slab that's often as annoying as it is effective. Bosch,
finally, has a better idea: An AI-enhanced LCD screen that links with a driver-monitoring
camera to keep the sun out of your eyes without blocking the outward view. The German
supplier debuted the Bosch Virtual Visor at the recent CES show in Las Vegas. The
Virtual Visor project began when Ryan Todd, a Bosch engineer in suburban Detroit,
started daydreaming about what TV he wanted to buy during his sun-stroked commute..."
 RF Cascade Workbook 2018 is the next phase in the evolution
of RF Cafe's long-running series, RF Cascade Workbook. 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...
 Unlike pervious enumerated "Gs," 5G is much
more than cellphone connectivity. 5G encompasses all forms and uses of super wide
bandwidth and upper GHz and even THz band operational frequencies. Cellphones represent
only a part of that paradigm. As stated in this article from the February 2020 issue
of
NASA Tech Briefs magazine, "For the first time, 5G offers a data rate and
reliability comparable to wired communication." Factory automation and "smart" networks
comprise a huge part of the 5G master plan. As such, security is a major concern,
since breaches dataflow can result in not just pilfered information, but the scuttling
of critical processes which could destroy manufacturing and associated profits.
Worst case scenarios include disruption of critical utility systems and even situations
harmful to the human population through contamination. This "5G
in Manufacturing: What's Here and What's to Come" article is definitely a good
read.
 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.
Monday 10
 QuinStar Technology will feature its cryogenic
product line at the American Physical Society March Meeting. This event is March
2nd through 4th at the Colorado Convention Center in Denver. QuinStar
cryogenic circulators, isolators, and arrays offer exceptional broadband performance
down to the mK range. These components support applications such as quantum computing,
radio astronomy, STM research, particle physics research, and electron spin resonance
measurement systems. QuinStar engineers have over 36 years of experience in cryogenic
ferrite design. With this extensive experience, we continually advance state-of-the-art...
 Less than a year had passed since the surprise
attack on Pearl Harbor by the
Japanese
navy when this article was published in QST. America had sprung into
high gear to help the war effort - both as civilians and as military members. A
vital part of the strategy was to educate as many people as possible regarding the
tactics and habits of the enemy. Media of all sorts were used to help get the word
out. QST did its part, probably more so than most forms of media, by appealing
to those people capable and willing to contribute to the vitally important task
of communications. How many hobbies could be directly applied to the needs of the
military and homeland defense? Precious few, other than radio design, assembling,
testing, and operation. I suppose to be fair I would have to mention a few other
hobbies like vehicular maintenance, firearms marksmanship, and model building...
 Transient Specialists specializes in
EMC test equipment rentals
and carries a complete line of ESD guns, surge immunity test equipment, and EFT
generators. Rentals available for military (Mil-Std 461), automotive (ISO 7637),
and commercial (IEC 61000-4) EMC testing. Flexible terms, accredited calibrations
and technical support on EMC testing equipment offered. Equipment consists of top
EMC Test System manufacturers, including Teseq, Thermo Keytek, EM Test and EMC Partner.
Contact Transient Specialists today for your ESD / EMC / RFI testing needs.
 This is amazing, especially considering
what good condition it is in. "The
Gilbert U-238 Atomic Energy Lab let kids measure radioactivity and prospect
for radioactive ores," so says the article on the IEEE Spectrum magazine
website. Along with a detailed description of the kit is a video explaining the
contents. "When the Atomic Energy Lab hit the market in 1950, it was one of the
most elaborate science kits available. In addition to uranium, it had beta-alpha,
beta, and gamma radiation sources. It contained a cloud chamber, a spinthariscope,
an electroscope, and a Geiger counter, as well as a 60-page instruction book." Author
Allison Marsh asks the legitimate question of whether today's overly protective
child safety laws have prevented science learning "toys" like this one from being
made available. As a kid, I had Gilbert chemistry sets that probably cannot be sold
today. BTW, you can buy
uranium ore on Amazon but your plutonium samples must be procured
from Libyan terrorists.
 TotalTemp Technologies has another good
blog article posted entitled, "Best
Thermal Testing Practices on an Electronic Device." There are many reasons thermal
testing on products is required. Primarily to verify that the product will work
properly in the environment (thermal and otherwise) that it is intended to perform.
Sometimes, also to discover end-of-life issues for products, maximize performance
or to weed out early failures that might result in product failures For reasons
primarily of simplicity and ease of use, the most widely employed method of forcing
products to temperatures for thermal testing is a (convection based) temperature
chamber. According to laws of Thermodynamics, heat transfer (in and out of a product)
is accomplished through one or more of the three following methods. Conduction,
convection and radiation...
 ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test Cables
for labs. ConductRF makes production and test coax cable assemblies for amplitude
and phased matched VNA applications as well as standard & precision RF connectors.
Over 1,000 solutions for low PIM in-building to choose from in the iBwave component
library. They also provide custom coax solutions for applications where some standard
just won't do. A partnership with Newark assures fast, reliable access. Please visit
ConductRF today to see
how they can help your project!
Sunday 9
 As with my hundreds of previous
science and engineering-themed crossword puzzles, this one for February 9, 2020,
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have built up 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.
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.
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