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4 of the August 2019 homepage archives. Friday 16
 If you are familiar with
Carl Kohler's illustrations from his numerous humorous (a rhyme!)
electronics-themed stories in Popular Electronics magazine, then this comic
from the May 1955 issue will be recognized as having come from his hand. The 1950s
through maybe the early 1980s was a big time for do-it-yourself hobbyists of all
sorts, including those who dabbled in electronics as Hams, household handymen, kit
builders, etc. In many cases high quality products could be purchased more cheaply
as kits, as evidenced by the popularity of Heathkit and similar companies. By the
mid to late 1990s, super-cheap labor - verging on slavery - in the Far East was
doing the majority of component production and product assembly, so eventually an
inversion ...
 Joel Brand has an interesting short article
posted on the Electronic Design website entitled, "The Rise and Fall of IoT in the 2.4-GHz Band." "Self-interference
cancellation could very well be the linchpin to a resurgence of the 2.4-GHz band.
Way back when the 5-GHz band was opened for unlicensed Wi-Fi usage, many predicted
the death of 2.4 GHz. The 5-GHz band enabled much faster speeds thanks to the increased
amount of bandwidth available at the higher frequency. Channels as wide as 160 MHz
were introduced (and the industry is mulling the introduction of 320-MHz channels),
whereas the entire 2.4-GHz band is only about 80 MHz wide. As the FCC and other
regulators are looking to open the 6-GHz band for Wi-Fi usage, there's no doubt
that consumer appetite for higher bandwidth and faster speed will be served at the
higher frequencies ..."
 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.
 This particular quiz tests your knowledge
of archaic scientific words &
definitions. Choose the best answer
for the spirit of the quiz; i.e., the one that represents the newer term or the
abandoned definition. All RF Cafe quizzes would make perfect fodder in employment
interviews for technicians or engineers - particularly those who are fresh out of
school or are relatively new to the work world. Come to think of it, they would
make equally excellent study material for the same persons who are going to be interviewed
for a job...
 "A superconducting qubit can be used to reliably
detect the presence of multiple phonons at the same time, US physicists have demonstrated.
Patricio Arrangoiz-Arriola and colleagues at Stanford University built their 'quantum microphone' using materials that minimized phonon losses,
while narrowing the spectra of their qubit's emissions to reduce uncertainties.
The technology could allow for new capabilities in quantum computing, including
modems that link together many quantum computers at different locations. While the
quantum properties of photons have been explored and exploited extensively ..."
 QuinStar Technology designs and manufactures
mm-wave products for communication,
scientific, and test applications along with providing microelectronic assembly,
rapid prototyping, and mass customization. Amplifiers, Oscillators, Switches, Attenuators,
Circulators, Isolators, Filters, Waveguide, Antennas, Phase Shifters, Transceivers,
Mixers, Detectors. QuinStar specializes in cryogenic amplifiers,
circulators, and isolators. Please visit QuinStar today to see how they can help
your project...
Thursday 15
 This article from a 1955 issue of Popular
Electronics magazine describes my evolution from electrician to electronics
technician to
electronics engineer. For that matter, it describes the paths
many people I have worked with over the years have taken. My mentor at my first
job as an RF engineer after graduating with a BSEE from the University of Vermont
began as a technician in the Army, and then he went to school part-time while working
a full-time job to earn his BSEE. In my next job as an RF engineer there were at
least two guys I knew who had also taken that path. Although not by any means absolute
criteria for judging an engineer's enthusiasm, I will say that at least as a distinct
segment of RF engineering, those who are amateur radio operators and/or those who
began life as a technician ...
 You and I know them as 'varactor diodes,' but originally the semiconductor junctions whose
reverse bias determines its capacitance was called the 'Varicap.' The new and wondrous
semiconductor craze was in full swing by 1958. Scientists, engineers, and hobbyists
were burning the midnight oil (to use a popular phrase of
the day) performing experiments and designing circuits to replace vacuum
tubes and manual controls with transistors and other electrically variable semiconductors.
The Varicap had the ability to tune receiver and transmitter oscillators and filters
without the need for high tube bias voltages and large mechanically variable multi-plate
capacitors. This article from Radio-Electronics says early Varicaps cost
$4.50 apiece ...
 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...
 Saelig Company has introduced the new
Rigol Technologies MSO8000 Series of digital oscilloscopes, which
combine best in class sampling (10 GSa/sec) and memory depth (500 Mpts)
with a modern, flexible user interface enabled by Rigol's new UltraVision II architecture
and innovative Phoenix chipset. Three models are available with input bandwidths
from 600 MHz to 2GHz, each with 4 analog channels. The series is MSO ready: an optional
16-channel logic analyzer interface is provided to provide digital debug capabilities
with the addition of 16 channel probes and software. The advanced MSO8000 Series
features a 10.1" 1024 x 600 capacitive multi-touch color LCD screen with 256-level
intensity grading and a waveform refresh rate ...
 "The botched production of a powerful neutrino
source is the most likely cause of a
radioactive cloud that enveloped much of Europe in the autumn
of 2017. That is the conclusion of a group of radiation experts from across the
continent who have used isotope monitoring and chemical analysis to try and understand
where the leak came from. The researchers think that the isotope involved - ruthenium-106
- was probably released during an accident, possibly an explosion, involving spent
fuel at the Mayak reprocessing plant in southern Russia. Aerosols containing ruthenium-106
were detected ..."
 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.
Wednesday 14
 Before the advent of electrical distribution
systems and electronics, the
hazard of lightning was primarily from fire ignition and, to a
lesser extent, bodily injury (to humans and animals). In fact, it was Benjamin Franklin's
discovery that lightning was a form of electricity that led to his subsequent invention
of the lightning rod system that, after being installed on Philadelphia's tallest
wooden structures, significantly reduced the incident of lightning-related devastating
fires which had been ravaging the city for years. Once cities began installing electric
power lines, they were to lightning what trailer homes* are to tornadoes - strong
attractors. Line protection systems were soon developed to help stop strikes which
sometimes caused electrocution to people inside homes who happened to be touching
a light switch or plumbing fixture ...
 "The U.S. Air Force announced Friday it will
soon deploy two ground-based laser weapons to an undisclosed location to test how
they can be used against small drones, the service's first 'operational field test'
of an experimental 'directed energy" weapon. On Friday afternoon the Air Force announced
a $23M sole-source contract for two of Raytheon's High Energy Laser Weapons Systems,
through which the systems are to be tested for 12 months in an undisclosed 'contested
environment' outside the continental United States. 'What we really want to do is
figure out how we can deploy these systems in an environment where our warfighters
work and train every day ..."
 RACEP (Random Access and Correlation for Extended
Performance), was an early form of frequency hopping spread spectrum (HFSS)
devised by the Martin Company (now Lockheed-Martin). It was used for secure voice
communications and worked by sampling speech in small 'slices' and then transmitting
each slice modulated onto a carrier whose frequency was determined by a predetermined
sequence of center frequencies. A receiver with a matching sequence key would then
decode the speech and, with appropriate filtering, reassemble it into its original
content. President John F. Kennedy had such systems at his disposal whether on the
road or in the Oval Office. General Electric (GE) had a different idea it dubbed
'Phantom' that spread the signal over a very wide bandwidth. Today, we refer to
it as Direct Sequence Spread Spectrum (DSSS) ...
 Signal Hound, a developer of optimized solutions
for RF signal test and measurement, announces a new
rental program for all Signal Hound spectrum analyzers, vector
signal generators, and tracking generators. Signal Hound's equipment rental rate
is only 6% of the cost of a device per month for as long as the renter wants to
keep the device, with a one-month minimum rental period. If the renter wants to
purchase the device after the rental period, 30% of the total amount spent on the
rented product can be applied to a new version of the same device type. "Our rental
program is designed to remove the hesitation that an organization might have in
allocating budget towards a new type of test equipment ...
 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. Take a couple minutes to visit their website and see how
IPP can help you today...
Tuesday 13
 If there was another episode of
Mac's Radio Service Shop where Barney was the primary teacher
and Mac was the student, I don't remember what it was. In fact, this is about as
total of a role reversal as there can be. First, Mac admits to having chased a presumed
oscilloscope issue down the proverbial rabbit hole only to realize the cause of
the problem was totally unrelated. Then, Barney produces a nifty device meant for
recording telephone conversations and demonstrates to Mac a couple ingenious applications
he discovered that were handy for troubleshooting television sets. When reading
Mac's description of using a magnet to alter the electron beam in a CRT, it reminded
me of how cool it was on the CRT displays to run a magnet ...
 ConductRF's close partnership with TE in
its development of its new Nano-miniature RF Solutions for
VITA67.3 has put us in a great position to support your VPX RF
cable assembly needs. Modular solution supports 8 to 18 positions, flexible 0.047"
diameter cable, supports frequency up to 70 GHz, use with standard solutions
(SMA, SMPM, etc.), 2x density of Vita67.1. ConductRF's PFT33 Series of Micro Flexible
Cable Assemblies has been designed directly with TE Connectivity involvement and
in partnership to maximize the capabilities of TE's new Vita67.3 NanoRF VPX modular
connector system. ConductRF offers its soft FEP jacketed ø0.047" cable to facilitate
maximum flexibility and provides solutions for jumper cables ...
 In keeping with a very common practice of
using water flowing through a garden hose as a teaching aid analogy for newcomers,
the title of this chapter of the NAVPER 10622 Basic Navy Training Courses, "Generators - Electrical Pumps," is likening electrical generators
to water pumps. It is an apt analogy, but whereas a water pump can cause water pressure
and flow of a physical substance already on-hand, electrical "pumps," aka generators,
literally creates its "flow" from thin air (even a vacuum with no air). An electrical
generator exploits the phenomenon discovered by (or at least credited to) Michael
Faraday whereby a conductor moving through a magnetic field - or a magnetic field
moving past a conductor ...
 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.
 This is part 2 of the High Frequency Electronics
article entitled, "An Analytical Model of Quad Cable to 1 GHz," by Kenneth Schneider.
It's not for the feint of heart. "Studies performed in developing the model indicate
that this is principally caused by the aperiodic twists and to a much lesser extent
by the increase in the imaginary component of the dielectric constant. Notice at
the extreme right-hand side of each of the figures- close to 1 GHz. This behavior
seems 'to burst out again.' Computations indicate that this is 'roughly' repetitive
in with increasing frequency. The presence of this behavior with |ELFEXT| repeatedly
going through 0 dB may well affect the cancellation of FEXT through vectoring ..."
 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.
Monday 12
 I remember seeing advertisements for the
"Geniac Electric Brain" in technical magazines like Popular
Electronics, Mechanix Illustrated, Popular Science, etc.,
back in the 1960s and 70s. Even then it seemed like a hokey attempt to pitch a mechanical
gizmo as an honest-to-goodness computer. Personal computers were still a decade
or more away and only multi-million-dollar mainframe computers were available, so
the opportunity for Joe Sixpack to own a "problem solving" computer was a real temptation.
No, I never bought one; my first computer was a second-hand Timex Sinclair 1000
with a membrane keyboard and a cassette tape deck as a program storage device. Anyway,
when I found this article in a 1966 issue of Popular Electronics, I figured
maybe other people of my vintage would enjoy reading about its inner workings ...
 The 12th UK/Europe-China Workshop on Millimetre-Waves and Terahertz Technologies
(UCMMT) 2019 will be held at the Graduate Centre, Queen Mary University of London
from August 20th to 22nd. The UCMMT was created in 2008 to stimulate and strengthen
scientific collaboration and knowledge and cultural exchange. The workshop is held
annually, alternating between Europe and China. This conference is now well established
and has become a special premier international forum for the exchange of ideas on
state-of-the-art research in mmWave and THz science and technologies. Keynote speakers
include Sir Colin Humphreys, Dr. Hanyang Wang, Professor Wei Hong, Prof. Yong Fan,
and Mr. David R. Vizard...
 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 7,000 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. Banner advertising begins
at $175/month...
 L-Com has a good
PDF document summarizing the flammability ratings of various types
of cable. They also have some short
videos showing how the cables react to a flame. These materials
appeared in an article in NASA's Motion Design magazine, which also included
a good definitions summary table of MICE (mechanical, ingress, climatic, and electromagnetic
) parameters in IE (Industrial Internet) standards. Many RF engineers must design
systems with user and control interface in these environments and need to be familiar
with the technology ...
 If you're a newcomer to the game, it may
seem that radio theory already has enough mystery without adding more. True, the
technical journals - even QST, sometimes - do make it a mysterious subject with
their textbook language and complex notations. Radio isn't really any more mysterious
or complex than many a detective story - at least not after you've read the last
page and know "whodunit." The difference lies in the method of presentation. There
may be some utility, then, in the idea of presenting radio fundamentals in the manner
of detective fiction. That's what this is - a series of radio lessons in the guise
of a detective-mystery yarn. Instead of human characters we'll use another kind
- but we'll try to make the characterizations true and the background and incident
realistic. Our purpose is to divert ...
 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.
Sunday 11
 This RF Cafe
Engineering & Science Crossword Puzzle contains at least 10
words from headlines posted on the homepage during the week of August 5 through
August 9, 2019 (marked with an asterisk*). These custom-made engineering and science-themed
crossword puzzles are done weekly for the brain-exercising benefit and pleasure
of RF Cafe visitors who are fellow cruciverbalists. Every word and clue - without
exception - in these RF Cafe puzzles has been personally entered into a very large
database that encompasses engineering, science, physical, astronomy, mathematics,
chemistry, etc. Let me know if you would like a custom crossword puzzle built for
your company, school, club, etc. (no charge).
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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